JP4581111B2 - Optical space communication device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical space communication device that is applied to perform optical communication using space propagation between space navigation objects such as artificial satellites, space stations, and spacecrafts, or between space navigation objects and ground stations. It is about.
[0002]
[Prior art]
In general, in an optical communication apparatus, an optical fiber system is employed in which communication stations are connected by an optical fiber cable, and optical communication is performed between the communication stations using the optical fiber cable as a transmission path. In such an optical communication system, it is possible to dramatically increase the communication capacity compared to conventional RF communication. By the way, in recent fields of space development, communication such as inter-satellite communication has been diversified, and an increase in communication capacity has been demanded. Therefore, in the field of space development, an optical communication system is constructed between a ground station and a spacecraft or between spacecrafts to increase the communication capacity and realize a variety of communications. There is a concept. For example, a plurality of artificial satellites (hereinafter referred to as “satellite”) launched in space orbit at a relatively low altitude from the earth are arranged at predetermined intervals, and a low-orbit satellite-to-satellite link that connects these satellites by communication is formed. It has been broken. Until now, the link between low-orbit satellites has been provided by radio communication, but optical communication using laser light is being considered instead.
[0003]
As an optical communication apparatus used for this type of optical communication, for example, there is one having the configuration shown in Japanese Patent Laid-Open No. 2000-180652, which is shown in FIG. In the figure, 110 is an optical antenna, 111 is a directivity adjusting mechanism, 112 is a collimator lens, 113 is a beam splitter, 114 is a condensing lens, 115 is a light detecting unit, and 116 is an optical antenna directing control unit. 117 is a reflecting mirror for adjusting an optical axis, 118 is an imaging lens, 119 is a beam splitter, 120 is an angle adjusting mechanism, 121 is a beam splitter, 122 is a light detecting unit, and 123 is a reflecting mirror angle control unit. Reference numeral 124 denotes a transmission lens, 125 denotes a beam splitter, 126 denotes an optical axis adjustment mechanism unit, 127 denotes an optical axis control unit, 128 denotes a light detection unit, and 129 denotes an optical fiber cable. 130 is an optical signal processing unit, 131 is a transmission unit, 132 is a reflecting mirror, 133 is a lens, 201 is a main reflecting mirror, 202 is a sub-reflecting mirror, and 203 is an indicating member.
[0004]
The optical communication apparatus shown in FIG. 8 adjusts the optical axis via an angle adjustment mechanism 120 on the optical path of communication light received by an optical antenna 110 that can freely adjust the direction of transmission and reception of communication light with a communication partner station. A transmissive lens 124 having an adjustable optical axis is arranged in order via a flexible reflector 117 and an optical axis adjusting mechanism 126, and the angle adjusting mechanism 120 is driven and controlled to adjust the optical axis of communication light. At the same time, the optical axis adjustment mechanism 126 is driven and controlled, and the alignment is adjusted in the same manner. The communication light after the alignment adjustment is optically coupled to one end of the optical fiber cable 129. As a result, the spatial propagation distance can be easily increased, and simple and highly accurate optical signal processing can be realized.
[0005]
Further, there is a conventional optical communication apparatus described in Japanese Patent Laid-Open No. 8-79184, and its configuration is shown in FIG. In the figure, 301 to 304 are light receiving units, 305 to 308 are optical fibers, 309 to 312 are optical amplifiers, 313 to 316 are photodiodes, and 317 is an arithmetic processing unit.
[0006]
The optical communication apparatus shown in FIG. 9 guides the laser light received by the four light receiving units 301 to 304 formed of an optical system to the optical amplifiers 309 to 312 through the optical fibers 305 to 308, and each light amplified by the optical amplifiers 309 to 312. The signal is detected by a four-quadrant photodetector composed of photodiodes 313 to 316, and the arithmetic processing unit 317 calculates a deviation in the incident direction of the laser light to the light receiving units 301 to 304 from the detection signals from the photodiodes 313 to 316. In addition, a part of the photodiodes 313 to 316 (for example, 316) is also used as a communication light receiving element. Thus, an amplified detection output similar to that of a four-divided avalanche photodiode can be obtained using a general photodiode, and can also be used as a light receiving element for communication.
[0007]
[Problems to be solved by the invention]
Since the conventional optical communication apparatus is configured as described above, there are the following problems in realizing the directional control that requires high accuracy and high reliability.
[0008]
The optical communication apparatus shown in FIG. 8 is a combination of a reflecting mirror 117 with adjustable optical axis, an angle adjusting mechanism 120, a transmissive lens 124 with adjustable optical axis, an optical axis adjusting mechanism 126, and the like. The installation space for the space and the device for driving them is large, and it is difficult to reduce the size and weight of the entire device, and it is not suitable for mounting on a satellite. In addition, since the control system of the reflecting mirror 117 that can adjust the optical axis and the control system of the transmissive lens 124 that can adjust the optical axis are independent, there is a possibility of interference between the control systems. Furthermore, since there are a plurality of control systems, there is a problem that the amount of control calculation increases and the control calculation speed decreases.
[0009]
On the other hand, since the optical communication apparatus shown in FIG. 9 uses part of the four photodiodes 313 to 316 as a light receiving element for communication, if the received light is uniformly incident on these photodiodes, the light receiving element for communication is used. There is a possibility that communication cannot be sufficiently performed with weak received light. Further, when the optical axis is adjusted so that the optical axis is incident on the center of the communication light receiving element so that the amount of light received by the communication light receiving element is maximized, the received light cannot enter all the remaining three photodiodes. There was a problem that the function as a quadrant sensor was impaired.
[0010]
The present invention has been made in order to solve the above-described problems, and enables communication even with weak received light, and can provide flexibility in the installation location of the receiver by reducing the size and weight. An object is to obtain a spatial communication device.
[0011]
The present invention provides an optical space communication device capable of quickly shifting to a communication mode and shortening the communication cut-off time even when the received light deviates from the field of view of the light receiving fiber coupler due to disturbance or the like and the received light cannot be guided to the receiver. With the goal.
[0012]
An object of the present invention is to obtain an optical space communication device that can guide received light to a receiver even when the received light on the light receiving fiber coupler cannot enter the entire optical position detecting function.
[0013]
An object of the present invention is to obtain an optical space communication device capable of guiding received light to a receiver even when the received light beam intensity pattern is complicated.
[0014]
An object of the present invention is to obtain an optical space communication device that can simplify the control system configuration without performing coordinate conversion on each sensor by canceling the received light rotation in the internal optical system due to the rotation of the coarse acquisition and tracking mechanism. And
[0015]
[Means to solve the problem]
An optical space communication device according to the present invention provides a coarse acquisition and tracking mechanism for roughly capturing the transmitted light from the partner station by roughly directing the light receiving unit of the transmission / reception telescope to the partner station by driving the gimbal in the elevation direction and the azimuth direction. A fine capture tracking mechanism that finely captures the received light roughly captured by the coarse capture tracking mechanism by driving the biaxial gimbal, and a coarse capture tracking mechanism gimbal angle sensor that detects a gimbal angle of the coarse capture tracking mechanism; A fine capture and tracking mechanism gimbal angle sensor for detecting the gimbal angle of the fine capture and tracking mechanism, a pointing sensor for detecting a relative angle error with a counterpart station in a wide range, the relative angle error detected by the pointing sensor and the rough angle Acquisition and tracking mechanism Adder for adding the gimbal angle detected by the gimbal angle sensor, and the relative angle error between the opposite station and the pointing As a target value to form a precise tracking control system at the time of capture, a tracking sensor that detects with higher accuracy and at a higher frequency than the sensor, a trajectory prediction value that predicts and sets the relative angle of the other station to its own station from the trajectory information As a command value set in advance, a command value set in advance as a target value for forming a fine capture tracking control system during tracking, and a target value for forming a fine capture tracking control system during communication A light receiving fiber coupler that is optically coupled to a receiver that demodulates received light into an electrical signal having a function for detecting a highly accurate optical position from the received light and a command value set during communication, and on the light receiving fiber coupler The received light angle deviation detector that calculates the amount of received light angle deviation, and the fine capture tracking mechanism gimbal angle at the time of tracking and communication from the detection output of the fine acquisition tracking mechanism gimbal angle sensor. A coarse / coordinate compensator that obtains a control target value for driving the coarse acquisition and tracking control mechanism so as to be set in the vicinity of the point, an output of the adder at the time of acquisition, the trajectory prediction value, and the coarse acquisition and tracking mechanism gimbal The correction amount of the gimbal angle given to the coarse acquisition tracking mechanism is calculated from the feedback amount of the output of the angle sensor, and the control target value, the trajectory prediction value, and the coarse acquisition are obtained from the coarse / coordinated compensator during tracking and communication. A coarse acquisition tracking compensator that calculates a correction amount of a gimbal angle given to the coarse acquisition tracking mechanism from a feedback amount of an output of the tracking mechanism gimbal angle sensor, and the acquisition command value and the fine acquisition tracking mechanism gimbal angle sensor at the time of acquisition The amount of correction of the gimbal angle of the fine capture and tracking mechanism is calculated from the feedback amount of the output of the tracking, and the tracking command value and the tracking sensor output The amount of correction of the gimbal angle given to the fine capture tracking mechanism is calculated from the back amount, and given to the fine capture tracking mechanism from the command value during communication and the feedback amount of the output of the received light angle deviation detector during communication. A fine acquisition and tracking compensator for calculating the correction amount of the gimbal angle and a control mode switching means for setting each control mode at the time of acquisition, tracking and communication.
[0016]
An optical space communication device according to the present invention provides a coarse acquisition and tracking mechanism for roughly capturing the transmitted light from the partner station by roughly directing the light receiving unit of the transmission / reception telescope to the partner station by driving the gimbal in the elevation direction and the azimuth direction. A fine capture tracking mechanism that finely captures the received light roughly captured by the coarse capture tracking mechanism by driving the biaxial gimbal, and a coarse capture tracking mechanism gimbal angle sensor that detects a gimbal angle of the coarse capture tracking mechanism; A fine capture and tracking mechanism gimbal angle sensor for detecting the gimbal angle of the fine capture and tracking mechanism, a pointing sensor for detecting a relative angle error with a counterpart station in a wide range, the relative angle error detected by the pointing sensor and the rough angle Acquisition and tracking mechanism Adder for adding the gimbal angle detected by the gimbal angle sensor, and the relative angle error between the opposite station and the pointing As a target value to form a precise tracking control system at the time of capture, a tracking sensor that detects with higher accuracy and at a higher frequency than the sensor, a trajectory prediction value that predicts and sets the relative angle of the other station to its own station from the trajectory information Pre-capturing command value, tracking command value set in advance as a target value for forming a fine capture and tracking control system during tracking, and a function to detect an ultra-high-precision optical position from received light A light receiving fiber coupler that optically couples to a receiver that demodulates received light into an electrical signal, a received light angle shift detector that calculates the received light angle shift amount on the light receiving fiber coupler, and the received light angle shift detection Received light offset calculator that calculates the offset amount given to the fine capture and tracking control system during communication from the output of the detector, and the tracking and communication from the detection output of the fine capture and tracking mechanism gimbal angle sensor A fine-coordinated compensator that obtains a control target value for driving the coarse-acquisition tracking control mechanism so that the gimbal angle of the fine-acquisition tracking mechanism is set near the origin, and the output of the adder and the trajectory during acquisition A correction amount of the gimbal angle to be given to the coarse acquisition tracking mechanism is calculated from the predicted value and the feedback amount of the output of the coarse acquisition tracking mechanism gimbal angle sensor, and a control target value from the fine coarse cooperative compensator at the time of tracking and communication A coarse acquisition tracking compensator for calculating a correction amount of a gimbal angle given to the coarse acquisition tracking mechanism from the predicted value of the trajectory and the feedback amount of the output of the rough acquisition tracking mechanism gimbal angle sensor; And the feedback amount of the output of the fine capture and tracking mechanism gimbal angle sensor to calculate the correction amount of the gimbal angle given to the fine capture and tracking mechanism, and the tracking command at the time of tracking A gimbal angle correction amount given to the fine capture and tracking mechanism is calculated from the value and the feedback amount of the tracking sensor output, and the output offset amount of the received light offset calculator and the feedback amount of the tracking sensor output during communication And a fine capture tracking compensator for calculating a correction amount to be given to the gimbal angle of the fine capture and tracking mechanism, and a control mode switching means for setting each control mode during capture, tracking and communication.
[0017]
The space optical communication apparatus according to the present invention includes an offset amount generator that extracts a constant offset amount when the output of the received light angle deviation detector is larger than the threshold value during communication, instead of the received light offset calculator. The fine acquisition and tracking compensator calculates the correction amount of the gimbal angle given to the fine acquisition and tracking mechanism from the feedback amount of the output of the tracking sensor and the constant offset amount during communication.
[0018]
In the optical space communication device according to the present invention, the control mode switching means determines the incident light angle from the detection output of the tracking sensor, and detects the angle shift of the received light on the light receiving fiber coupler from the output of the received light angle shift amount detector. By determining, each control mode at the time of acquisition, tracking and communication is switched and set.
[0019]
In the optical space communication device according to the present invention, the control mode switching means switches between the coarse acquisition and tracking control system during communication and the tracking control mode, and the fine acquisition and tracking control system during acquisition and tracking. And a second switch that switches and sets the control mode during communication, and a tracking sensor angle that determines the incident light angle from the detection output of the tracking sensor and sets the first switch to either the communication or tracking control mode. A determination unit, a reception light angle deviation amount determination unit for determining an angle deviation of reception light on the light receiving fiber coupler from an output of the reception light angle deviation amount detector and extracting a determination output for determining tracking and communication; and the tracking sensor A control mode for either capturing, tracking, or communicating when the second switch is captured in response to both outputs of the angle determiner and the received light angle deviation determiner Those having a switch automatic switch to be set.
[0020]
An optical space communication apparatus according to the present invention includes a single mode fiber in which a pointing sensor is configured by a two-dimensional CCD, a tracking sensor is configured by a four quadrant detector, and a light receiving fiber coupler optically couples received light to a receiver. It is composed of a multimode fiber that is arranged around the mode fiber and detects the position of the received light.
[0021]
An optical space communication device according to the present invention provides a coarse acquisition and tracking mechanism for roughly capturing the transmitted light from the partner station by roughly directing the light receiving unit of the transmission / reception telescope to the partner station by driving the gimbal in the elevation direction and the azimuth direction. A fine capture tracking mechanism that finely captures the received light roughly captured by the coarse capture tracking mechanism by driving the biaxial gimbal, and a coarse capture tracking mechanism gimbal angle sensor that detects a gimbal angle of the coarse capture tracking mechanism; A fine capture and tracking mechanism gimbal angle sensor for detecting the gimbal angle of the fine capture and tracking mechanism, a pointing sensor for detecting a relative angle error with a counterpart station in a wide range, the relative angle error detected by the pointing sensor and the rough angle Acquisition and tracking mechanism An adder that adds the gimbal angle detected by the gimbal angle sensor, and the relative angle of the partner station with respect to its own station from the trajectory information Predicted trajectory value, acquisition command value set in advance as a target value for forming a fine acquisition and tracking control system during acquisition, and preset value as a target value for forming a fine acquisition and tracking control system during communication A receiving fiber coupler that optically couples to a receiver that demodulates received light into an electrical signal, and has a function of detecting an optical position from the received light and an ultra-high accuracy optical position from the received light; The received light angle deviation detector for calculating the angle deviation amount and the coarse acquisition tracking mechanism gimbal angle so that the fine acquisition tracking mechanism gimbal angle is set near the origin during tracking and communication from the detection output of the fine acquisition tracking mechanism gimbal angle sensor. A coarse / coordinate compensator that obtains a control target value for driving the acquisition / tracking control mechanism, and outputs the output of the adder, the trajectory prediction value, and the output of the rough acquisition / tracking mechanism gimbal angle sensor during acquisition. The amount of correction of the gimbal angle to be given to the coarse acquisition tracking mechanism is calculated from the back amount, and the control target value, the trajectory prediction value, and the output of the coarse acquisition tracking mechanism gimbal angle sensor during communication are calculated. From the feedback amount, the coarse acquisition tracking compensator for calculating the correction amount of the gimbal angle to be given to the coarse acquisition tracking mechanism, the acquisition time command value at the time of acquisition and the feedback amount of the output of the fine acquisition tracking mechanism gimbal angle sensor A correction amount of the gimbal angle given to the fine capture and tracking mechanism is calculated, and a gimbal angle correction amount given to the fine capture and tracking mechanism is calculated from the command value at the time of communication and the feedback amount of the received light angle deviation detector during communication. And a fine-tracking and tracking compensator for calculating the control mode, and a control mode switching means for setting a control mode at the time of acquisition and at the time of communication.
[0022]
In the optical space communication device according to the present invention, the control mode switching means determines the incident light angle from the detection output of the tracking sensor, and detects the angle shift of the received light on the light receiving fiber coupler from the output of the received light angle shift amount detector. By determining, the control mode at the time of acquisition and communication is switched and set.
[0023]
In the optical space communication device according to the present invention, when the adder cannot obtain a detection output when the pointing sensor is not receiving light, the adder holds the output value when receiving light in advance.
[0024]
Furthermore, an optical space communication device according to the present invention includes an image rotation detector that detects a rotation angle of received light generated in the internal optical system by rotating the coarse acquisition and tracking mechanism, and a rotation mechanism that rotates the internal optical system. And a rotation mechanism control circuit that drives and controls the rotation mechanism so as to cancel the image rotation generated in the internal optical system in response to the detection output of the image rotation detector.
[0025]
The optical space communication device according to the present invention is configured to roughly direct the light receiving unit to the other station by a rough acquisition tracking mechanism driven by gimbal and to direct the light reception unit to the other station by a fine acquisition tracking mechanism driven by gimbal. In an optical space communication device to be controlled, an image rotation detector that detects a rotation angle of received light generated in an internal optical system by rotating the coarse acquisition and tracking mechanism, a rotation mechanism that rotates the internal optical system, A rotation mechanism control circuit that drives and controls the rotation mechanism so as to cancel image rotation generated in the internal optical system in response to a detection output of an image rotation detector.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described below.
Embodiment 1 FIG.
FIG. 1 is a block diagram showing a schematic configuration of an optical space communication apparatus according to the present invention. In FIG. 1, 101 is a transmission light from a partner station, 102 receives this transmission light 101, and transmits a transmission light of the own station. A transmission / reception telescope 103 for launching is a light receiving section thereof. Reference numeral 1 denotes a secondary mirror of the transmission / reception telescope 102, and 2 denotes a primary mirror that captures the transmission light 102. Reference numeral 3 denotes a tertiary mirror which is used for guiding the component of the transmission light 102 reflected by the primary mirror 2, that is, the reception light, through the secondary mirror 1 into the elevation axis. Reference numeral 4 denotes a quaternary mirror for guiding the received light passing through the tertiary mirror 3 into the azimuth axis. A coarse acquisition tracking mechanism 5 captures the transmission light 101 from the other station by driving the transmission / reception telescope 102 in the elevation direction and roughly directing the light receiving unit 103 of the transmission / reception telescope 102 toward the other station. Reference numeral 6 denotes a coarse acquisition tracking mechanism which drives the transmission / reception telescope 102 in the azimuth direction and coarsely faces the light receiving unit 103 of the transmission / reception telescope 102 to the other station together with the coarse acquisition tracking mechanism 5 to acquire transmission light. Reference numeral 7 denotes a frame for installing the coarse capturing and tracking mechanism 6, 8 is a support for coupling the frame 7 to the installation surface, and 9 is an internal optical system on which sensors and an optical system are mounted. Reference numeral 10 denotes a fine-acquisition tracking mechanism including a reflecting mirror driven by a two-axis gimbal in order to further finely capture and track the received light roughly captured by the operations of the coarse-acquisition tracking mechanisms 5 and 6.
[0027]
Reference numerals 11 and 14 denote beam splitters. Reference numeral 12 denotes a pointing sensor that is used for coarse acquisition tracking and includes a two-dimensional CCD or the like that detects a relative angle error from the received light in a wide range. Reference numeral 13 is a dichroic mirror, and 15 is a tracking sensor that is used for fine capture and tracking, and is composed of a four-quadrant detector or the like that can detect a relative angle error with a counterpart station from received light with higher accuracy and higher frequency than the pointing sensor 12. Reference numerals 16 and 19 denote reflecting mirrors, and 26 denotes a receiver that processes received light and demodulates it into an electrical signal. Reference numeral 17 denotes a light receiving fiber coupler with an ultra-high accuracy optical position detection function for guiding received light to the receiver 26, and has a structure as will be described later with reference to FIG.
[0028]
Reference numeral 18 denotes a two-axis driveable optical difference correction mechanism that adjusts the optical difference correction angle in the direction in which the local station transmits to the partner station. Reference numeral 20 denotes a transmitter that generates transmission light from the own station, and reference numeral 21 denotes an installation surface of the transmission / reception telescope 102. Reference numeral 22 denotes a coarse acquisition and tracking mechanism control circuit that drives and controls the coarse acquisition and tracking mechanisms 5 and 6. Reference numeral 23 denotes a received light angle deviation detector that calculates the received light angle deviation on the light receiving fiber coupler 17. Reference numeral 24 denotes a fine acquisition and tracking mechanism control circuit that drives and controls the fine acquisition and tracking mechanism 10, and 25 denotes an optical fiber that optically couples the received light from the light receiving fiber coupler 17 to the receiver 26. 33 is a control target value for driving the coarse acquisition tracking control mechanisms 5 and 6 so that the fine acquisition tracking mechanism gimbal angle is set in the vicinity of the origin at the time of tracking and communication from the detection output of the fine acquisition tracking mechanism gimbal angle sensor 36. It is a rough cooperative compensator to obtain
[0029]
FIG. 2 is a block diagram showing a signal processing process of the space optical communication apparatus according to Embodiment 1 of the present invention. In FIG. 2, 30 is composed of an encoder or the like and detects the gimbal angles of the coarse acquisition tracking mechanisms 5 and 6. This is a rough capture and tracking mechanism gimbal angle sensor. Reference numeral 27 denotes an adder that adds the output of the pointing sensor 12 at the time of light reception and the output of the coarse capture tracking mechanism gimbal angle sensor 30 at that time. A coarse acquisition tracking compensator 28 calculates the correction amount of the gimbal angle of the coarse acquisition tracking mechanisms 5 and 6 in each control mode during acquisition, tracking, and communication. A sampler 29 samples the output of the coarse capture tracking mechanism gimbal angle sensor 30 in accordance with the output period of the pointing sensor 12. Reference numeral 31 denotes a predicted trajectory value obtained by predicting and setting the relative angle of the partner station to the own station from the trajectory information.
[0030]
Reference numeral 32 denotes a first switch for switching the target value of the coarse acquisition and tracking control system between acquisition and tracking. Reference numeral 36 denotes a fine capture and tracking mechanism gimbal angle sensor that includes a displacement sensor and detects the gimbal angle of the fine capture and tracking mechanism 10. Reference numeral 34 denotes a capture time command value preset as a target value for forming a fine capture and tracking control system at the time of capture, and reference numeral 35 denotes a tracking time command value preset as a target value for forming the fine capture and tracking control system during tracking. It is. Reference numeral 38 denotes a fine acquisition and tracking compensator that calculates the correction amount of the gimbal angle of the fine acquisition and tracking mechanism 10 in each control mode during acquisition, tracking and communication. Reference numeral 37 denotes a second switch for switching each control mode during capture, tracking and communication when the input of the fine capture and tracking compensator 38 is captured, and constitutes the control mode switching means of the present invention together with the first switch 32. Reference numeral 39 denotes a command value at the time of communication set in advance as a target value for forming a fine capture and tracking control system at the time of communication.
[0031]
FIG. 3 is a perspective view showing a configuration example of the light receiving fiber coupler 17, in which 40 is a single mode fiber for optically coupling received light to the receiver 26, and 41, 42, 43, and 44 are single mode fibers 40. Is a multimode fiber for detecting the position of the received light on the light receiving fiber coupler 17 disposed around the center of the optical fiber.
[0032]
Next, the operation will be described.
The operation of this optical space communication device includes a capture mode in which the light receiving unit 103 of the transmission / reception telescope 102 is roughly directed toward the other station to roughly capture the transmitted light from the other station, and a tracking mode in which the coarsely received light is finely captured. And the communication mode in which communication is performed by the receiver 26 and the transmitter 20 in a state where the target station is determined.
[0033]
At the time of acquisition, the first switch 32 and the second switch 37 are connected to the acquisition mode side a in the circuit of FIG.
The pointing sensor 12 detects a relative angle error with the counterpart station in a wide range.
Therefore, the purpose of the coarse acquisition tracking control system is to perform control so that the detection output indicating the relative angle error of the pointing sensor 12 becomes zero. A two-dimensional CCD is usually used as the pointing sensor 12, but it takes time for detection, and an output can be obtained only at intervals of several tens of milliseconds. Therefore, when the output of the pointing sensor 12 is obtained in order to increase the control band, the detection output representing the gimbal angle of the rough acquisition tracking mechanism gimbal angle sensor 30 at that time is sampled by the sampler 29 in accordance with that, and the adder 27 In addition, it is set as the target value of the coarse acquisition and tracking control system.
[0034]
The predicted trajectory value 31 is further added to the target value of the coarse acquisition and tracking control system. This assumes that the relative angle of the other station is predicted from the own station's orbit information and the other station's orbit information, assuming that the optical space communication device communicates between artificial satellites. Even when 12 is not receiving light, the coarse acquisition and tracking mechanisms 5 and 6 can be controlled by the open loop control so that the light receiving unit 103 is substantially directed to the opposite station. Using the sum of the output of the adder 27 and the predicted trajectory value 31 as a target value, the detection output of the coarse acquisition tracking mechanism gimbal angle sensor 30 is fed back to constitute the coarse acquisition tracking control system. The deviation between the target value and the feedback amount is input to the coarse acquisition and tracking compensator 28. The coarse acquisition and tracking compensator 28 performs coarse acquisition and tracking mechanism 5, so that this deviation becomes zero by PID (Proportional Integration and Differential) control or the like. 6 is driven.
[0035]
Next, the function of the adder 27 will be described. Here, for the sake of explanation, the influence of the predicted trajectory value 31 is omitted, but even when the predicted trajectory value 31 is included, the function is exactly the same.
The coarse acquisition and tracking compensator 28 operates so that the output of the coarse acquisition and tracking mechanism gimbal angle sensor 30 is equal to the detection output of the pointing sensor 12. However, the operation of the coarse acquisition and tracking mechanisms 5 and 6 is hardly directed to the opposite station due to the characteristics of the coarse acquisition tracking compensator 28 or errors included in the pointing sensor 12, and some errors remain. This error can be detected by the next signal from the pointing sensor 12. Since this error is relative to the state of the coarse capture tracking mechanisms 5 and 6 at that time, in order to give an absolute target value of the gimbal angle, the coarse capture tracking mechanism gimbal angle sensor 30 at that time is used. Must be added. This is the role of the adder 27.
[0036]
Further, when the pointing sensor 12 is not receiving light and no detection output is obtained, the adder 27 operates so as to hold the output value when receiving light in advance. As a result, even if the movement of the other station is fast and the coarse acquisition and tracking control system cannot reduce the error to the position required for tracking and cannot enter the other station's tracking, the coarse acquisition and tracking mechanisms 5 and 6 can continue. Until the other station is captured, the transmission / reception telescope 102 can be directed toward the other station. Therefore, at the next light reception by the pointing sensor 12, the initial error is reduced and the tracking can be surely started.
[0037]
Further, in order to control the gimbal angle of the fine capture and tracking mechanism 10 to a neutral point, the detection output of the fine capture and tracking mechanism gimbal angle sensor 36 is fed back to constitute a fine capture and tracking control system. The capture command value 34 is 0, but an offset can also be given. The deviation between the acquisition command value 34 and the feedback amount is input to the fine acquisition and tracking compensator 38, and the fine acquisition and tracking compensator 38 drives the fine acquisition and tracking mechanism 10 so that the deviation becomes zero by PID control or the like. .
[0038]
Next, at the time of tracking, that is, when the optical space communication apparatus enters the tracking stage for accurately capturing the partner station from the stage of capturing the partner station, the first switch 32 and the second switch 37 are each switched to the tracking mode side b.
At the time of tracking, higher pointing accuracy is required for aiming at the other station. Therefore, it is necessary to switch the sensor from a pointing sensor 12 such as a two-dimensional CCD to a tracking sensor 15 such as a four quadrant detector. In addition, both the fine capture tracking control system and the coarse capture tracking control system must be operated cooperatively so as not to deviate from the drive range of the fine capture tracking mechanism 10.
[0039]
In order to operate both the fine capture tracking control system and the coarse capture tracking control system in a coordinated manner, the value of the fine capture tracking mechanism gimbal angle sensor 36 is used to return it to the neutral point. 6 is driven. That is, first, the output of the fine acquisition and tracking mechanism gimbal angle sensor 36 is input to the fine and coarse cooperative compensator 33, where, for example, integration control or the like is performed, and then the predicted trajectory value 31 is added to the target value of the coarse acquisition and tracking compensator 28. And Therefore, the first switch 32 is switched to the tracking mode side b, and the target value of the coarse acquisition tracking control system is switched. In this way, the coarse acquisition and tracking mechanisms 5 and 6 move to return the gimbal angle of the fine acquisition and tracking mechanism 10 to the neutral point regardless of the value of the pointing sensor 12, so that both control systems interfere with each other. Therefore, the fine capture and tracking control system can achieve high precision tracking accuracy without departing from the drive range of the fine capture and tracking mechanism 10.
[0040]
At the time of tracking, in order to guide the received light to the origin of the tracking sensor 15, the detection output of the tracking sensor 15 is fed back to configure a fine capture tracking control system. The tracking command value 35 is 0, but an offset can be given. The deviation between the tracking command value 35 and the amount of footback is input to the fine acquisition and tracking compensator 38, and the fine acquisition and tracking compensator 38 drives the fine acquisition and tracking mechanism 10 so that this deviation becomes zero by PID control or the like. To do.
[0041]
Next, at the time of communication, that is, when the optical space communication apparatus enters the stage of communicating with the partner station from the stage of tracking the partner station, the first switch 32 is in the tracking mode side b and the second switch 37 is on the communication mode side. Switch to c.
During communication, in order to guide received light to the receiver 26, higher directivity accuracy is required. Therefore, the second switch 37 switches the tracking sensor 15 to one using the position detection function of the light receiving fiber coupler 17 and switches the configuration of the fine acquisition and tracking control system.
[0042]
At the time of communication, in order to guide the received light to the center of the light receiving fiber coupler 17 shown in FIG. 3, that is, the center of the single mode fiber 40, the multimode fibers 41, 42, 43, and 44 for detecting the received light position are used. Are input to the received light angle deviation detector 23 to calculate the received light angle deviation amount on the light receiving fiber coupler 17. The amount of received light angle deviation is fed back to constitute a fine capture tracking control system.
The communication command value 39 is 0, but an offset can be given. The deviation between the communication command value 39 and the feedback amount is input to the fine acquisition and tracking compensator 38, and the fine acquisition and tracking compensator 38 drives the fine acquisition and tracking mechanism 10 so that the deviation becomes zero by PID control or the like. . Accordingly, the received light is guided to the center of the single mode fiber 40, and sufficient received light can be guided to the receiver 26.
[0043]
The received light angle deviation detector 23 is provided with a photodiode (not shown) for converting received light optically coupled from the multimode fibers 41, 42, 43, and 44 into an electrical signal. The received light positional deviation is detected by adding and subtracting the outputs from the respective photodiodes by a method equivalent to that of the 4-quadrant detector, and converted into the driving angle of the fine capture and tracking mechanism 10. Similarly, the receiver 26 includes a photodiode (not shown) for converting received light optically coupled from the single mode fiber 40 into an electrical signal.
[0044]
By converting the received light optically coupled to the receiver 26 by the optical fiber 25 into an electrical signal, the influence of electrical noise can be suppressed and communication can be performed even with weak light.
Further, since there is no restriction on the routing of the optical fiber 25, the degree of freedom of the installation place of the receiver 26 is increased. The single mode fiber 40 for guiding light to the receiver 26 and the multimode fibers 41, 42, 43, 44 for detecting the light position around the single mode fiber 40 are integrated to reduce the size and weight of the sensor and save space. Can be planned.
[0045]
In the example described above, three control modes for capture, tracking, and communication are assumed. However, errors in installing optical systems such as the pointing sensor 12 and the light receiving fiber coupler 17 can be ignored, and the pointing sensor 12 is high. When the angle can be detected with accuracy, the capture mode can be shifted to the communication mode suddenly, and the optical space communication device can be configured with these two types of control modes. Therefore, in that case, the tracking sensor 15 and the tracking command value 35 can be omitted.
[0046]
As described above, according to the first embodiment, the tracking and tracking can be performed only by the coarse and tracking control mechanisms 5 and 6 and the fine and tracking control mechanism 10, so that the optical space communication device can be reduced in size and weight. The effect that can be obtained. Further, the light receiving unit 103 can be captured and tracked at a high speed and with a wide range and with high accuracy with respect to the partner station, and attachment errors of the pointing sensor 12, the tracking sensor 15, and the light receiving fiber coupler 17 can be adjusted. Since the cancellation is controlled by the control of the acquisition and tracking mechanism 10, the effect of smoothly shifting from the acquisition mode to the tracking mode and reliably maintaining the tracking without causing interference between the coarse acquisition and tracking control system and the fine acquisition and tracking control system. Is obtained. Further, after directing the received light from the partner station with high accuracy in the tracking mode, the mode is changed from the tracking mode to the communication mode, and the light receiving fiber coupler 17 with an ultra-high accuracy optical position detection function is used to direct the light with higher accuracy. Since the received light is guided to the receiver 26 by the control, it is possible to communicate even if the received light is weak, and the effect of increasing the degree of freedom of the installation location of the receiver 26 can be obtained.
[0047]
Embodiment 2. FIG.
FIG. 4 is a block diagram showing a signal processing process of the space optical communication apparatus according to Embodiment 2 of the present invention, and parts corresponding to those in FIG. In the figure, 45 is a tracking sensor angle determiner, which determines whether or not the received light is incident within the field of view of the tracking sensor 15, and whether or not the received light is incident within a certain set high-precision directivity angle. The incident light angle is determined, and the first switch 62 is automatically set to one of the control modes during communication and tracking. Reference numeral 46 denotes a received light angle shift amount determination unit for determining whether the received light on the light receiving fiber coupler 17 is incident on the field of view of the light receiving fiber coupler 17, that is, determining the angle shift of the received light. 47 is an automatic switch selector, and automatically responds to the outputs of the tracking sensor angle determination unit 45 and the received light angle deviation amount determination unit 46 and automatically switches to the control mode at the time of capturing, tracking or communication. Is to switch automatically.
[0048]
Next, the operation will be described.
At the time of initial capture or the like, the tracking sensor 15 is in a non-light-receiving state, so that the tracking sensor angle determination unit 45 sets both the first switch 32 and the second switch 37 to the capture mode side a.
When the received light is incident on the field of view of the tracking sensor 15, the tracking sensor angle determination unit 45 switches the first switch 32 to the tracking mode side b, and the second switch 37 is also switched to the tracking mode side b through the automatic switch 47. Switch to. Further, when the received light is incident within a set high-precision directivity angle of the tracking sensor 15 at the time of tracking, the tracking sensor angle determiner 45 switches the second switch 37 to the communication mode side c by the switch automatic switch 47. Here, the value of the high-precision directivity angle set by the tracking sensor 15 is given so that the received light enters the field of view of the light receiving fiber coupler 17 if it is within this set value. Therefore, at the time of communication, both outputs from the tracking sensor angle determination unit 45 and the received light angle deviation amount determination unit 46 are output so that the second switch 37 is set to the communication mode.
[0049]
When the received light deviates from the field of view of the light receiving fiber coupler 17 due to disturbance or the like, the received light angle deviation amount determination unit 46 determines that communication is impossible, and the automatic switch 47 switches the second switch 37 from the communication mode side c to the tracking mode side. Switch to b. At the time of tracking, if the received light is incident within a set high-precision directivity angle of the tracking sensor 15, the tracking sensor angle determination unit 45 causes the second switch 37 to be set to the communication mode side again by the automatic switch 47. When the received light deviates from the field of view of the tracking sensor 15, the determination output of the doraking sensor angle determination unit 45 is given to the switch automatic switch 47 and the second switch 37 is moved from the tracking mode side b. Simultaneously with switching to the acquisition mode side a, the first switch 32 is also switched from the tracking mode side b to the acquisition mode side a.
[0050]
In the example described above, three control modes for capture, tracking, and communication are assumed. However, errors in installing optical systems such as the pointing sensor 12 and the light receiving fiber coupler 17 can be ignored, and the pointing sensor 12 is high. When the angle can be detected with accuracy, the capture mode can be shifted to the communication mode suddenly, and the optical space communication device can be configured with these two types of control modes. Therefore, in this case, the tracking sensor 15 and the tracking command value 35 can be omitted, and the tracking mode can be omitted. Therefore, the tracking sensor angle determination unit 45 can also be omitted as a configuration of the control mode switching means.
[0051]
As described above, according to the second embodiment, the 17 capture mode, the tracking mode, and the communication mode are automatically switched and set using the detection output of the tracking sensor 15 and the light receiving fiber coupler. Even when the received light deviates from the field of view of the tracking sensor 15, the mode can be shifted to the tracking mode immediately after entering the capture mode, and the received light deviates from the field of view of the light receiving fiber coupler 17 due to disturbance or the like and is received by the receiver 26. Even when light cannot be guided, it becomes possible to shift to the communication mode immediately after shifting to the tracking mode, and the effect of shortening the communication interruption time can be obtained.
[0052]
Embodiment 3 FIG.
FIG. 5 is a block diagram showing a signal processing process of the space optical communication apparatus according to Embodiment 3 of the present invention. Parts corresponding to those in FIG. 2 and FIG. . In the figure, reference numeral 48 denotes a received light offset calculator which obtains an output for offsetting the detection output of the tracking sensor 15 from the output of the received light angle deviation detector 23. Reference numeral 49 denotes a third switch for switching the target value to the fine capture and tracking control system in the tracking mode and the communication mode.
[0053]
Next, the operation will be described.
At the time of capturing such as initial capturing, the tracking sensor 15 is in a non-light-receiving state, and therefore the tracking sensor angle determination unit 45 sets the first switch 32 and the second switch 37 to the capturing mode side a. In this case, the capture command value 34 is given to the fine capture and tracking compensator 38 to constitute a fine capture and tracking control system. When the coarse acquisition is performed and the received light enters the visual field of the tracking sensor 15, the tracking sensor angle determination unit 45 moves the first switch 32, the second switch 37, and the third switch 49 from the acquisition mode side a to the tracking mode. Switch to side b.
[0054]
At the time of tracking, the output of the tracking sensor 15 is fed back in order to guide the received light to the origin of the tracking sensor 15 to constitute a fine capture tracking control system. The tracking command value 35 is 0, but an offset can be given. The deviation between the tracking command value 35 and the feedback amount is input to the fine acquisition tracking compensator 38, and the fine acquisition tracking compensator 38 drives the fine acquisition tracking mechanism 10 so that this deviation becomes zero by PID control or the like. .
[0055]
Further, when received light is incident within a set high-precision directional angle of the tracking sensor 15 during tracking, the tracking sensor angle determination unit 45 causes the automatic switch 47 to switch the third switch 49 from the tracking mode side b to the communication mode. Switch to side c. Here, the value of the high-precision directivity angle set by the tracking sensor 15 is given so that the received light enters the field of view of the light receiving fiber coupler 17 if it is within this set value. At the time of communication, the output of the tracking sensor 15 is fed back so as to follow the output of the received light offset calculator 48 to constitute a fine capture tracking control system. The deviation between the output signal of the received light offset calculator 48 and the feedback amount is input to the fine acquisition and tracking compensator 38. The fine acquisition and tracking compensator 38 has a fine acquisition and tracking mechanism so that this deviation becomes zero by PID control or the like. 10 is driven.
[0056]
Next, the operation of the received light offset calculator 48 will be described.
A single mode fiber 40 for optically coupling the received light to the receiver 26 with a signal detected by any of the multimode fibers 41, 42, 43, 44, which is the optical position detection function of the light receiving fiber coupler 17 of FIG. 3. Compared with the above signal, it is converted into the driving angle amount of the fine capture and tracking mechanism 10 and added to the output signal of the tracking sensor 15 as an offset amount. With this offset, the received light can be guided to the receiver 26.
When the received light is incident on the single mode fiber 40 of the light receiving fiber coupler 17, but the received light is not incident on all of the multimode fibers 41, 42, 43, and 44 for the optical position detection function, that is, a received light spot is generated. Even when the received light is small, the received light has a certain intensity distribution, so even if the received light angle slightly fluctuates, the angle change is detected by the received light angle deviation detector 23 and the photodiode provided in the receiver 26. The offset amount to the fine capture and tracking control system can be calculated.
[0057]
When the received light deviates from the field of view of the light receiving fiber coupler 17 due to disturbance or the like during communication, the received light angle deviation determiner 46 determines that communication is impossible, and the automatic switch 47 switches the third switch 49 to the tracking mode side b. Switch to. In a state where the tracking sensor 15 returns, when received light is incident within a set high-precision directivity angle of the tracking sensor 15, the determination output of the tracking sensor angle determination unit 45 is given to the switch automatic switch 47 and the third switch 49 is switched to the communication mode side c again. However, when the received light deviates from the field of view of the tracking sensor 15, the tracking sensor angle determination unit 45 moves the first switch 32 and the second switch 37 from the tracking mode side b to the acquisition mode side. Switch to a.
[0058]
As described above, according to the third embodiment, since the capture mode, the tracking mode, and the communication mode can be automatically switched, even when the received light deviates from the field of view of the tracking sensor 15 due to a disturbance or the like, the capture mode Even if the received light is deviated from the field of view of the light receiving fiber coupler 17 due to disturbance or the like, and the received light cannot be guided to the receiver 26 due to disturbance or the like, the communication mode is immediately entered after the shift to the tracking mode. The effect of shortening the communication interruption time can be obtained.
Further, by providing the received light offset calculator 48, even when the received light spot is small at the time of communication and cannot enter all of the optical position detecting function unit of the light receiving fiber coupler 17, the received light is sent to the receiver 26 by the offset amount. The effect that light can be guided is obtained.
[0059]
Embodiment 4 FIG.
FIG. 6 is a block diagram showing a signal processing process of the space optical communication apparatus according to Embodiment 4 of the present invention, and parts corresponding to those in FIG. In the figure, reference numeral 50 denotes an offset amount generator for giving the output from the received light angle deviation detector 23 to the tracking sensor 15 as an offset, which is replaced with the received light offset calculator 48 of the third embodiment. Is.
[0060]
Next, the operation will be described.
Since the tracking sensor 15 is in a non-light-receiving state during the acquisition mode such as the initial acquisition, the tracking sensor angle determination unit 45 sets the first switch 32 and the second switch 37 to the acquisition mode side a. In this case, the capture command value 34 is given to the fine capture and tracking compensator 38 to constitute a fine capture and tracking control system. When the coarse acquisition is performed and the received light enters the visual field of the tracking sensor 15, the tracking sensor angle determination unit 45 moves the first switch 32, the second switch 37, and the third switch 49 from the acquisition mode side a to the tracking mode. Switch to side b.
[0061]
At the time of tracking, the output of the tracking sensor 15 is fed back in order to guide the received light to the origin of the tracking sensor 15 to constitute a fine capture tracking control system. The tracking command value 35 is 0, but an offset can be given. The deviation between the tracking command value 35 and the feedback amount is input to the fine acquisition tracking compensator 38, and the fine acquisition tracking compensator 38 drives the fine acquisition tracking mechanism 10 so that this deviation becomes zero by PID control or the like. .
Further, when received light is incident within a set high-precision directional angle of the tracking sensor 15 during tracking, the tracking sensor angle determination unit 45 causes the automatic switch 47 to switch the third switch 49 from the tracking mode side b to the communication mode. Switch to side c. Here, the value of the high-precision directivity angle set by the tracking sensor 15 is given so that the received light enters the field of view of the light receiving fiber coupler 17 if it is within this set value.
[0062]
At the time of communication, the output of the tracking sensor 15 is fed back so as to follow the output signal of the offset amount generator 50 to constitute a fine capture tracking control system. The deviation between the output signal of the offset amount generator 50 and the feedback amount is input to the fine acquisition and tracking compensator 38, and the fine acquisition and tracking compensator 38 uses the fine acquisition and tracking mechanism 10 so that the deviation becomes zero by PID control or the like. Drive.
[0063]
Next, the operation of the offset amount generator 50 will be described.
The signal detected by any of the multimode fibers 41, 42, 43, and 44, which is the optical position detection function of the light receiving fiber coupler 17, is compared with a set threshold value for allowing the received light to enter the single mode fiber 40. To do. When the signal detected by any of the multimode fibers 41, 42, 43, 44 is larger than this threshold, a certain offset amount converted to the drive angle amount of the fine capture tracking mechanism 10 is output. This is added to the output of the tracking sensor 15.
Then, a certain amount of offset is continuously added until the signal detected from any of the multimode fibers 41, 42, 43, and 44 becomes smaller than the set threshold value. That is, assuming that a certain offset amount is s, the output of the offset amount generator 50 in the first cycle is A (1) = s, and the output of the offset amount generator 50 in the second cycle is A (2) = s + s. = 2 × A, and the output of the offset amount generator 50 in the nth cycle is A (n) = s × n.
When the signal detected by any of the multimode fibers 41, 42, 43, 44 becomes smaller than the set threshold value, the offset amount generator 50 outputs 0. The received light can be guided to the receiver 26 by this offset operation.
[0064]
When the received light is incident on the single mode fiber 40 of the light receiving fiber coupler 17, but the received light is not incident on all of the multimode fibers 41, 42, 43, and 44 for the optical position detection function, that is, a received light spot is generated. Even when the received light is small, the received light has a certain intensity distribution, so even if the received light angle slightly fluctuates, the angle change is performed by the photo die auto provided in the received light angle deviation detector 23 and the receiver 26. Even when the detected light beam intensity pattern is complicated, the received light beam intensity can be binarized with a certain threshold value to guide the received light to the receiver 26.
[0065]
Next, when the received light deviates from the field of view of the light receiving fiber coupler 17 due to disturbance or the like during communication, the received light angle deviation determiner 46 determines that communication is impossible, and the automatic switch 47 switches the third switch 49 to the communication mode side c. To the tracking mode side b. When the tracking light returns to the tracking mode 15 and the received light is incident within a set high-precision directivity angle, the tracking sensor angle determination unit 45 causes the automatic switch 47 to switch the third switch 49 to the communication mode side c. However, when the received light deviates from the field of view of the tracking sensor 15, the tracking sensor angle determination unit 45 switches the first switch 32 and the second switch 37 from the tracking mode side b to the acquisition mode side a.
[0066]
As described above, according to the fourth embodiment, since the acquisition mode, the tracking mode, and the communication mode are automatically switched, even when the received light is deviated from the field of view of the tracking sensor 15 due to disturbance or the like, the mode is changed to the acquisition mode. Even when the mode immediately shifts to the tracking mode and the received light deviates from the field of view of the light receiving fiber coupler 17 due to disturbance or the like and the received light cannot be guided to the receiver 26, the mode immediately shifts to the tracking mode. The effect of shortening the communication interruption time can be obtained. Further, by providing the offset amount generator 50, even when the received light spot is small at the time of communication and cannot enter all of the optical position detecting function unit of the light receiving fiber coupler 17, the receiver 26 can be provided by giving a constant offset amount. In addition, since the received light can be guided, the function of the receiver 26 can be prevented from being impaired even when the received light beam intensity pattern is complicated.
[0067]
Embodiment 5 FIG.
FIG. 7 is a block diagram showing a schematic configuration of the optical space communication apparatus according to Embodiment 5 of the present invention. The parts corresponding to those in FIG. In the figure, 51 is an image rotation detector for detecting the rotation angle of received light generated by the rotation of the coarse acquisition and tracking mechanisms 5 and 6, 53 is a rotation mechanism for rotating the internal optical system 9, and 52 is This is a rotation mechanism control circuit that drives and controls the rotation mechanism 53 in response to the detection output from the image rotation detector 51.
[0068]
Next, the operation will be described.
In the acquisition mode, the tracking mode, or the communication mode, the coarse acquisition and tracking mechanisms 5 and 6 rotate to acquire and track the transmission light 101 from the counterpart station. In the case of FIG. 1, at this time, the received light rotates in the internal optical system as the coarse acquisition and tracking mechanisms 5 and 6 rotate, so that it is necessary to perform coordinate conversion on each sensor that receives the received light. In the configuration of the fifth embodiment, this influence is canceled by the rotation mechanism 53.
When the coarse capturing and tracking mechanisms 5 and 6 rotate, the image rotation detector 51 calculates the image rotation angle in the internal optical system and takes out an output indicating the corresponding amount. Next, upon receiving an output corresponding to the calculated rotation angle, the rotation mechanism control circuit 52 calculates a rotation angle command value for the rotation mechanism 53 so as to cancel the image rotation generated in the internal optical system 9, and takes out the control output. . The rotation mechanism 53 is rotated by the control output from the rotation mechanism control circuit 52, and the generated image rotation is canceled.
[0069]
As described above, according to the fifth embodiment, the rotation of the received light in the internal optical system 9 due to the rotation of the coarse acquisition and tracking mechanisms 5 and 6 can be canceled in the acquisition mode, the tracking mode, and the communication mode. Thus, there is no need to perform coordinate conversion, and the control system configuration can be simplified.
[0070]
【The invention's effect】
As described above, according to the present invention, the coarse acquisition and tracking mechanism for roughly capturing the transmitted light from the counterpart station by roughly directing the light receiving unit of the transmission / reception telescope to the counterpart station by driving the gimbal in the elevation direction and the azimuth direction. A fine capture tracking mechanism that finely captures the received light roughly captured by the coarse capture tracking mechanism by two-axis gimbal driving, a coarse capture tracking mechanism gimbal angle sensor that detects the gimbal angle of the coarse capture tracking mechanism, Fine capture tracking mechanism gimbal angle sensor that detects the gimbal angle of the capture tracking mechanism, a pointing sensor that detects the relative angle error with the partner station in a wide range, the relative angle error detected by the pointing sensor, and the coarse capture tracking mechanism gimbal angle An adder that adds the gimbal angle detected by the sensor and the relative angle error between the partner station and the higher accuracy and higher frequency than the pointing sensor Tracking sensor that is detected in, a predicted trajectory value that predicts the relative angle of the other station to its own station from trajectory information, and a command value at the time of capture that is preset as a target value for forming a fine capture and tracking control system at the time of capture And a tracking command value preset as a target value for forming a fine capture tracking control system during tracking, and a communication command value preset as a target value for forming a fine capture tracking control system during communication And a light receiving fiber coupler that optically couples to a receiver that has a function of detecting the optical position of the received light from the received light and demodulates the received light into an electrical signal, and calculates an angle shift amount of the received light on the light receiving fiber coupler. Coarse capture tracking control so that the fine capture tracking mechanism gimbal angle is set near the origin during tracking and communication from the detection output of the received light angle deviation detector and the detection output of the fine capture tracking mechanism gimbal angle sensor A coarse / coordinate compensator that obtains a control target value for driving the structure, and a gimbal that is given to the coarse acquisition and tracking mechanism from the output of the adder, the trajectory prediction value, and the output of the coarse acquisition and tracking mechanism gimbal angle sensor during acquisition The angle correction amount is calculated, and the gimbal angle given to the coarse acquisition and tracking mechanism is calculated from the control target value from the precision coarse compensator, the predicted trajectory value, and the feedback amount of the coarse acquisition and tracking mechanism gimbal angle sensor during tracking and communication. The coarse capture tracking compensator that calculates the correction amount of the signal, and the correction value of the gimbal angle of the fine capture tracking mechanism is calculated from the command value at the time of capture and the feedback amount of the output of the gimbal angle sensor at the time of capture. Calculate the correction amount of the gimbal angle given to the fine tracking mechanism from the tracking command value and tracking sensor output feedback amount. Fine capture tracking compensator that calculates the correction amount of the gimbal angle given to the fine capture tracking mechanism from the feedback amount of the output of the degree deviation detector, and a control mode that sets each control mode during capture, tracking, and communication Since the switching means is provided, there is an effect that the light receiving unit can be captured and tracked with respect to the counterpart station at a high speed in a wide range and with high accuracy. In addition, since the attachment error of the pointing sensor, tracking sensor, and optical fiber coupler can be canceled by controlling the coarse acquisition tracking mechanism and acquisition tracking mechanism, the acquisition is possible without causing interference between the coarse acquisition tracking control system and the fine acquisition tracking control system. There is an effect that the mode can be smoothly changed to the tracking mode and the tracking can be reliably maintained. Furthermore, after directing the received light from the partner station with high accuracy in the tracking mode, the mode is changed from the tracking mode to the communication mode, and the optical fiber coupler with an ultra-high accuracy optical position detection function is used for even higher accuracy. Since the received light is guided to the receiver by directivity control, there is an effect of enabling communication even if the received light is weak. In addition, since the received light is optically coupled to the receiver using a light receiving fiber coupler, it is possible to give flexibility to the installation location of the receiver, and in addition, a coarse capture tracking control mechanism and a fine capture as a mechanism. Since capture and tracking can be performed with the configuration of only the tracking control mechanism, the entire optical space communication device has the effect of reducing the size and weight.
[0071]
According to the present invention, the coarse acquisition tracking mechanism for roughly capturing the transmitted light from the other station by roughly directing the light receiving unit of the transmission / reception telescope to the other station by driving the gimbal in the elevation direction and the azimuth direction, and the coarse acquisition tracking The fine capture tracking mechanism that finely captures the received light roughly captured by the mechanism by driving the biaxial gimbal, the coarse capture tracking mechanism gimbal angle sensor that detects the gimbal angle of the coarse capture tracking mechanism, and the gimbal of the fine capture tracking mechanism Gimbal angle sensor with fine capture and tracking mechanism that detects angle, pointing sensor that detects relative angle error with a partner station in a wide range, and relative angle error detected by pointing sensor and gimbal detected by coarse capture and tracking mechanism gimbal angle sensor A corner angle adder and a relative angle error between the partner station and the tones that detect the relative angle error with higher accuracy and higher frequency than the pointing sensor. A tracking sensor, a trajectory prediction value that predicts and sets the relative angle of the partner station to the own station from the trajectory information, a capture command value that is set in advance as a target value for forming a fine capture and tracking control system at the time of capture, A command value at the time of tracking that is set in advance as a target value for forming a fine capture and tracking control system, and a receiver that demodulates the received light into an electrical signal that has a function to detect the optical position from the received light. The optical fiber coupler to be coupled, the optical angle deviation detector for calculating the optical angle deviation of the reception on the optical fiber coupler, and the output of the optical angle deviation detector for the received light are given to the fine capture tracking control system at the time of communication. The received light offset calculator that calculates the offset amount and the detection output of the fine capture tracking mechanism gimbal angle sensor so that the fine capture tracking mechanism gimbal angle is set near the origin during tracking and communication. Coarse and coarse compensator that obtains the control target value for driving the coarse acquisition and tracking control mechanism, and the coarse acquisition and tracking from the output of the adder, the predicted trajectory value, and the output of the coarse acquisition and tracking mechanism gimbal angle sensor during acquisition The correction amount of the gimbal angle given to the mechanism is calculated, and the coarse acquisition tracking mechanism is calculated from the control target value from the precision coarse compensator and the predicted trajectory and the feedback amount of the output of the coarse acquisition tracking mechanism gimbal angle sensor during tracking and communication. The coarse capture tracking compensator that calculates the correction amount of the gimbal angle given to the sensor, and the correction amount of the gimbal angle given to the fine capture tracking mechanism from the command value during capture and the feedback amount of the output of the fine capture tracking mechanism gimbal angle sensor during capture Calculate the gimbal angle correction amount given to the fine capture tracking mechanism from the tracking command value and tracking sensor output feedback amount at the time of tracking. A fine capture tracking compensator that calculates the amount of correction given to the gimbal angle of the fine capture and tracking mechanism from the output offset amount of the received light offset calculator and the feedback amount of the tracking sensor output, and each of the capture, tracking, and communication Since the control mode switching means for setting the control mode is provided, there is an effect that the light receiving unit can be captured and tracked with respect to the counterpart station at a high speed in a wide range and with high accuracy. In addition, since the attachment error of the pointing sensor, tracking sensor, and optical fiber coupler can be canceled by controlling the coarse acquisition tracking mechanism and acquisition tracking mechanism, the acquisition is possible without causing interference between the coarse acquisition tracking control system and the fine acquisition tracking control system. There is an effect that the mode can be smoothly changed to the tracking mode and the tracking can be reliably maintained. Furthermore, after directing the received light from the partner station with high accuracy in the tracking mode, the mode is changed from the tracking mode to the communication mode, and the optical fiber coupler with an ultra-high accuracy optical position detection function is used for even higher accuracy. Since the received light is guided to the receiver by directing control, communication is possible even if the received light is weak, and the received light on the light receiving fiber coupler is incident on the entire optical position detection function unit Even when it is not possible, there is an effect that the received light can be guided to the receiver. In addition, since the received light is optically coupled to the receiver using a light receiving fiber coupler, it is possible to give flexibility to the installation location of the receiver, and in addition, a coarse capture tracking control mechanism and a fine capture as a mechanism. Since capture and tracking can be performed with the configuration of only the tracking control mechanism, the entire optical space communication device has the effect of reducing the size and weight.
[0072]
According to this invention, instead of the received light offset calculator, the offset amount generator for extracting a constant offset amount when the output of the received light angle deviation detector is larger than the threshold value during communication is provided, and the fine acquisition tracking is provided. The compensator is configured to calculate the correction amount of the gimbal angle given to the fine capture and tracking mechanism from the feedback amount of the tracking sensor output and a fixed offset amount during communication, so the light receiving unit can There is an effect that it is possible to capture and track in a wide range and with high accuracy. In addition, since the attachment error of the pointing sensor, tracking sensor, and optical fiber coupler can be canceled by controlling the coarse acquisition tracking mechanism and acquisition tracking mechanism, the acquisition is possible without causing interference between the coarse acquisition tracking control system and the fine acquisition tracking control system. There is an effect that the mode can be smoothly changed to the tracking mode and the tracking can be reliably maintained. Furthermore, after directing the received light from the partner station with high accuracy in the tracking mode, the mode is changed from the tracking mode to the communication mode, and the optical fiber coupler with an ultra-high accuracy optical position detection function is used for even higher accuracy. Since the received light is guided to the receiver by directing control to the receiver, communication is possible even if the received light is weak, the received light spot on the light receiving fiber coupler is small, and the entire optical position detecting function unit Even when it cannot be incident, it is possible to guide the received light to the receiver by giving a certain amount of offset, and there is an effect that the function of the receiver is not impaired even when the received light beam intensity pattern is complicated. In addition, since the received light is optically coupled to the receiver using a light receiving fiber coupler, it is possible to give flexibility to the installation location of the receiver, and in addition, a coarse capture tracking control mechanism and a fine capture as a mechanism. Since capture and tracking can be performed with the configuration of only the tracking control mechanism, the entire optical space communication device has the effect of reducing the size and weight.
[0073]
According to the present invention, the control mode switching means determines the incident light angle from the detection output of the tracking sensor, and determines the angle deviation of the received light on the light receiving fiber coupler from the output of the received light angle deviation amount detector. Since it is configured to switch and set each control mode at the time of acquisition, tracking and communication, the acquisition mode, tracking mode and communication mode can be switched automatically, and received light from the tracking sensor field of view due to disturbance etc. Even in the event of a loss of time, the mode can be shifted to the tracking mode immediately after shifting to the capture mode, and even when the received light is removed from the optical fiber coupler field of view due to disturbance or the like and cannot be guided to the receiver, the mode is switched to the tracking mode. It is possible to quickly return to the communication mode and to shorten the communication interruption time.
[0074]
According to the present invention, the control mode switching means switches the control mode between the coarse acquisition tracking control system during communication and during tracking, and the fine acquisition tracking control system during acquisition, during tracking, and during communication. A second switch that switches and sets the control mode, a tracking sensor angle determiner that determines the incident light angle from the detection output of the tracking sensor and sets the first switch to one of the control modes for communication and tracking, and reception Received angle deviation detector, tracking sensor angle determiner, and received light to detect the angle deviation of the received light on the optical fiber coupler from the output of the optical angle deviation detector and extract the determination output that determines the tracking and communication time Automatic switch switching that sets the control mode to either the tracking, tracking, or communication mode when the second switch is captured in response to both outputs of the angle deviation detector The capture mode, tracking mode, and communication mode can be automatically switched, and even if the received light falls off the tracking sensor field of view due to disturbances, etc., immediately after entering the capture mode Even when the received light cannot be guided to the receiver due to disturbance or the like due to disturbance or the like, it is possible to switch back to the communication mode immediately after switching to the tracking mode, and the communication cut-off time There is an effect that can be shortened.
[0075]
According to the present invention, the pointing sensor is composed of a two-dimensional CCD, the tracking sensor is composed of a four quadrant detector, and the light receiving fiber coupler is a single mode fiber for optically coupling the received light to the receiver, and the single mode fiber is centered. Since it is configured with a multimode fiber to detect the position of the received light, it can detect the received light accurately according to the function of each control mode at the time of acquisition, tracking and communication. This can be performed and has an effect of sufficiently maintaining the control of the capture and tracking mechanism.
[0076]
According to the present invention, the coarse acquisition tracking mechanism for roughly capturing the transmitted light from the other station by roughly directing the light receiving unit of the transmission / reception telescope to the other station by driving the gimbal in the elevation direction and the azimuth direction, and the coarse acquisition tracking The fine capture tracking mechanism that finely captures the received light roughly captured by the mechanism by driving the biaxial gimbal, the coarse capture tracking mechanism gimbal angle sensor that detects the gimbal angle of the coarse capture tracking mechanism, and the gimbal of the fine capture tracking mechanism Gimbal angle sensor with fine capture and tracking mechanism that detects angle, pointing sensor that detects relative angle error with a partner station in a wide range, and relative angle error detected by pointing sensor and gimbal detected by coarse capture and tracking mechanism gimbal angle sensor An adder that adds angles, a predicted trajectory value that predicts the relative angle of the partner station to its own station from the trajectory information, An acquisition command value preset as a target value for forming a tracking control system, a command value for communication preset as a target value for forming a fine acquisition tracking control system at the time of communication, and an extremely high value from received light A light receiving fiber coupler that optically couples to a receiver that demodulates the received light into an electrical signal with a function of detecting the optical position of accuracy, and a received light angular deviation detector that calculates the amount of angular deviation of the received light on the light receiving fiber coupler. And a fine target value for driving the coarse acquisition and tracking control mechanism so that the fine acquisition and tracking mechanism gimbal angle is set near the origin during tracking and communication from the detection output of the fine acquisition and tracking mechanism gimbal angle sensor. Calculate the correction amount of the gimbal angle given to the coarse acquisition tracking mechanism from the cooperative compensator, the output of the adder at the time of acquisition, the predicted trajectory value, and the feedback amount of the output of the coarse acquisition tracking mechanism gimbal angle sensor, The coarse acquisition tracking compensator calculates the correction amount of the gimbal angle given to the coarse acquisition tracking mechanism from the control target value from the fine coarse adjustment compensator and the predicted trajectory value and the feedback amount of the output of the coarse acquisition tracking mechanism gimbal angle sensor. And the correction value of the gimbal angle given to the fine capture and tracking mechanism is calculated from the capture command value during capture and the feedback amount of the output of the fine capture and tracking mechanism gimbal angle sensor. A fine acquisition tracking compensator for calculating the correction amount of the gimbal angle given to the fine acquisition tracking mechanism from the feedback amount of the detector output, and a control mode switching means for setting a control mode at the time of acquisition and communication Since it is configured, errors in the installation of optical systems such as pointing sensors and optical fiber couplers can be ignored, and the pointing sensor can detect angles with high accuracy. It can be applied when using a device, and the transition from the capture mode to the communication mode can be made suddenly, and capture control of the optical space communication device can be performed in these two types of control modes, so that the device configuration can be further simplified. .
[0077]
According to the present invention, the control mode switching means determines the incident light angle from the detection output of the tracking sensor, and determines the angle deviation of the received light on the light receiving fiber coupler from the output of the received light angle deviation amount detector. Since it is configured to switch and set the control mode at the time of capture and communication, the capture mode and communication mode can be switched automatically, even when the received light deviates from the tracking sensor field of view due to disturbance etc. Even after switching to the capture mode, it is possible to switch to the communication mode as soon as possible, and even if the received light is removed from the field of view of the fiber optic coupler due to disturbances and cannot be guided to the receiver, the mode immediately returns to the communication mode after entering the capture mode. There is an effect that the communication can be shifted and the communication interruption time can be shortened.
[0078]
According to the present invention, when the pointing sensor cannot obtain a detection output when no light is received, the adder holds the output value at the previous light reception as it is. Even if the coarse acquisition tracking control system cannot reduce the error to the point required for tracking or communication mode and cannot enter the other station's tracking, the transmission / reception will not be performed until the coarse acquisition tracking mechanism next acquires the other station. The telescope can be pointed in the direction of the other station, and the initial error is reduced at the time of the next light reception of the pointing sensor, and there is an effect that the tracking or communication mode is surely entered.
[0079]
According to the present invention, an image rotation detector that detects the rotation angle of the received light generated in the internal optical system by rotating the coarse acquisition tracking mechanism, a rotation mechanism that rotates the internal optical system, and an image rotation detector Since there is a rotation mechanism control circuit that drives and controls the rotation mechanism so as to cancel the image rotation generated in the internal optical system in response to the detection output, the coarse acquisition tracking is performed in the acquisition mode, the tracking mode, and the communication mode. The rotation of the received light in the internal optical system due to the rotation of the mechanism can be canceled, and there is no need to perform coordinate conversion on each sensor, and the control system configuration can be simplified.
[0080]
According to the present invention, an optical space communication device for controlling the light receiving unit to be directed toward the other station with high precision by using the gimbal driven coarse acquisition and tracking mechanism to roughly direct the light receiving unit to the other station and using the gimbal driven fine acquisition and tracking mechanism. In response to the detection output of the image rotation detector, the rotation mechanism for rotating the internal optical system, and the rotation output of the image rotation detector. And a rotation mechanism control circuit for driving and controlling the rotation mechanism so as to cancel the image rotation generated in the internal optical system, so that the rotation of the coarse acquisition tracking mechanism is rotated in the acquisition mode, the tracking mode, and the communication mode. The rotation of the received light in the internal optical system can be canceled, and there is no need to perform coordinate conversion on each sensor, and the control system configuration can be simplified.
[Brief description of the drawings]
FIG. 1 is a configuration diagram showing an outline of an optical space communication apparatus according to Embodiment 1 of the present invention;
FIG. 2 is a block diagram showing a signal processing process of the optical space communication apparatus according to the first embodiment of the present invention.
FIG. 3 is a perspective view showing a configuration example of a light receiving fiber coupler according to Embodiment 1 of the present invention.
FIG. 4 is a block diagram showing a signal processing process of an optical space communication apparatus according to Embodiment 2 of the present invention.
FIG. 5 is a block diagram showing a signal processing process of an optical space communication apparatus according to Embodiment 3 of the present invention.
FIG. 6 is a block diagram showing a signal processing process of an optical space communication apparatus according to Embodiment 4 of the present invention.
FIG. 7 is a configuration diagram showing an outline of an optical space communication apparatus according to Embodiment 5 of the present invention;
FIG. 8 is a configuration diagram illustrating an example of a conventional optical communication device.
FIG. 9 is a configuration diagram illustrating another example of a conventional optical communication device.
[Explanation of symbols]
1 secondary mirror, 2 primary mirror, 3 tertiary mirror, 4 quaternary mirror, 5, 6 coarse capture tracking mechanism, 7 mounts, 8 struts, 9 internal optics, 10 fine capture tracking mechanism, 11, 14 beam splitter, 12 Pointing sensor, 13 Dichroic mirror, 15 Tracking sensor, 16, 19 Reflecting mirror, 17 Light receiving fiber coupler, 18 Optical line difference correction mechanism, 20 Transmitter, 21 Installation surface, 22 Coarse capture tracking mechanism control circuit, 23 Received light angle deviation Quantity detector, 24 fine acquisition tracking mechanism control circuit, 25 optical fiber, 26 receiver, 27 adder, 28 coarse acquisition tracking compensator, 29 sampler, 30 coarse acquisition tracking mechanism gimbal angle sensor, 31 orbit predicted value, 32 1 switch, 33 fine coordination compensator, 34 command value at the time of acquisition, 35 command value at the time of tracking, 36 fine acquisition and tracking mechanism gimbal angle sensor, 37 second switch, 38 Acquisition and tracking compensator, 39 Command value during communication, 40 Single mode fiber, 41, 42, 43, 44 Multimode fiber, 45 Tracking sensor angle determiner, 46 Received light angle deviation amount determiner, 47 Switch automatic switch, 48 Received light offset calculator, 49 Third switch, 50 Offset amount generator, 51 Image rotation detector, 52 Rotating mechanism control circuit, 53 Rotating mechanism, 101 Transmitted light, 102 Transmitting / receiving telescope, 103 Light receiving unit, 110 Optical antenna, 111 Direction adjustment mechanism, 112 Collimator lens, 113 Beam splitter, 114 Condensing lens, 115 Light detection unit, 116 Optical antenna directivity control unit, 117 Optical axis adjustment reflector, 118 Imaging lens, 119 Beam splitter, 120 Angle adjustment mechanism 121 Beam splitter 122 Photodetector 123 Reflector angle control unit, 124 transmission lens, 125 beam splitter, 126 optical axis adjustment mechanism unit, 127 optical axis control unit, 128 light detection unit, 129 optical fiber cable, 130 optical signal processing unit, 131 transmission unit, 132 reflection mirror 133 lens, 201 main reflecting mirror, 202 sub-reflecting mirror, 203 indicator member, 301 to 304 light receiving unit, 305 to 308 optical fiber, 309 to 312 optical amplifier, 313 to 316 photodiode, 317 arithmetic processing unit.

Claims (10)

A coarse acquisition and tracking mechanism for roughly capturing the transmitted light from the counterpart station by roughly directing the light receiving unit of the transmission / reception telescope to the counterpart station by driving the gimbal in the elevation direction and the azimuth direction,
A fine capture tracking mechanism that finely captures the reception light roughly captured by the coarse capture tracking mechanism by driving the biaxial gimbal;
A coarse capture tracking mechanism gimbal angle sensor for detecting a rough capture tracking mechanism gimbal angle;
A fine capture tracking mechanism gimbal angle sensor for detecting a gimbal angle of the fine capture tracking mechanism;
A pointing sensor that detects a relative angle error with a partner station in a wide range;
An adder that adds the relative angle error detected by the pointing sensor and the gimbal angle detected by the rough capture tracking mechanism gimbal angle sensor;
A tracking sensor for detecting a relative angle error with a counterpart station with higher accuracy and higher frequency than the pointing sensor;
Orbit prediction value that predicts and sets the relative angle of the partner station to its own station from the orbit information,
A command value at the time of capture preset as a target value for forming a fine capture and tracking control system at the time of capture,
A tracking command value set in advance as a target value for forming a fine capture tracking control system at the time of tracking,
A command value at the time of communication set in advance as a target value for forming a fine capture and tracking control system at the time of communication,
A light receiving fiber coupler that optically couples to a receiver that demodulates the received light into an electrical signal having a function of detecting the optical position of the light from the received light;
A received light angular deviation detector for calculating the angular deviation of the received light on the light receiving fiber coupler;
From the detection output of the fine capture and tracking mechanism gimbal angle sensor, a precise control target value for driving the coarse capture and tracking control mechanism is obtained so that the fine capture and tracking mechanism gimbal angle is set in the vicinity of the origin during tracking and communication. A coarse cooperative compensator;
The correction amount of the gimbal angle given to the coarse acquisition tracking mechanism is calculated from the output of the adder at the time of acquisition, the predicted value of the trajectory, and the feedback amount of the output of the rough acquisition tracking mechanism gimbal angle sensor. Coarse acquisition tracking compensation for calculating the correction amount of the gimbal angle to be given to the coarse acquisition tracking mechanism from the control target value from the fine coarse adjustment compensator, the predicted trajectory value, and the feedback amount of the output of the rough acquisition tracking mechanism gimbal angle sensor And
The amount of correction of the gimbal angle of the fine capture tracking mechanism is calculated from the command value at the time of capture and the feedback amount of the output of the gimbal angle sensor of the fine capture tracking mechanism at the time of capture, and the command value at the time of tracking and the tracking sensor The amount of correction of the gimbal angle given to the fine capture tracking mechanism is calculated from the feedback amount of output, and the fine capture tracking mechanism is calculated from the command value during communication and the feedback amount of the output of the received light angle deviation detector during communication. A fine acquisition tracking compensator that calculates the correction amount of the gimbal angle given to
An optical space communication device comprising control mode switching means for setting each control mode during capture, tracking, and communication. A coarse acquisition and tracking mechanism for roughly capturing the transmitted light from the counterpart station by roughly directing the light receiving unit of the transmission / reception telescope to the counterpart station by driving the gimbal in the elevation direction and the azimuth direction,
A fine capture tracking mechanism that finely captures the reception light roughly captured by the coarse capture tracking mechanism by driving the biaxial gimbal;
A coarse capture tracking mechanism gimbal angle sensor for detecting a rough capture tracking mechanism gimbal angle;
A fine capture tracking mechanism gimbal angle sensor for detecting a gimbal angle of the fine capture tracking mechanism;
A pointing sensor that detects a relative angle error with a partner station in a wide range;
An adder that adds the relative angle error detected by the pointing sensor and the gimbal angle detected by the rough capture tracking mechanism gimbal angle sensor;
A tracking sensor for detecting a relative angle error with a counterpart station with higher accuracy and higher frequency than the pointing sensor;
Orbit prediction value that predicts and sets the relative angle of the partner station to its own station from the orbit information,
A command value at the time of capture preset as a target value for forming a fine capture and tracking control system at the time of capture,
A tracking command value set in advance as a target value for forming a fine capture tracking control system at the time of tracking,
A light receiving fiber coupler that optically couples to a receiver that demodulates the received light into an electrical signal having a function of detecting the optical position of the light from the received light;
A received light angular deviation detector for calculating a received optical angular deviation on the light receiving fiber coupler;
A received light offset calculator for calculating an offset amount to be given to the fine capture tracking control system during communication from the output of the received light angle deviation amount detector;
From the detection output of the fine capture and tracking mechanism gimbal angle sensor, a precise control target value for driving the coarse capture and tracking control mechanism is obtained so that the fine capture and tracking mechanism gimbal angle is set in the vicinity of the origin during tracking and communication. A coarse cooperative compensator;
The correction amount of the gimbal angle to be given to the coarse acquisition tracking mechanism is calculated from the output of the adder at the time of acquisition, the predicted trajectory value, and the feedback amount of the output of the rough acquisition tracking mechanism gimbal angle sensor. Coarse acquisition tracking compensation for calculating the correction amount of the gimbal angle to be given to the coarse acquisition tracking mechanism from the control target value from the fine coarse adjustment compensator, the predicted trajectory value, and the feedback amount of the output of the rough acquisition tracking mechanism gimbal angle sensor And
The correction value of the gimbal angle given to the fine capture and tracking mechanism is calculated from the command value at the time of capture and the feedback amount of the output of the fine capture and tracking mechanism gimbal angle sensor at the time of capture, and the tracking command value and the tracking sensor at the time of tracking are calculated. A gimbal angle correction amount given to the fine capture tracking mechanism is calculated from the feedback amount of the output of the output, and the fine capture tracking is calculated from the output offset amount of the received light offset calculator and the feedback amount of the output of the tracking sensor during communication. A fine tracking tracking compensator that calculates the amount of correction given to the gimbal angle of the mechanism;
An optical space communication device comprising control mode switching means for setting each control mode during capture, tracking, and communication. Instead of the received light offset calculator, an offset amount generator is provided that extracts a fixed offset amount when the output of the received light angle deviation detector is larger than the threshold during communication. 3. The optical space communication apparatus according to claim 2, wherein a gimbal angle correction amount to be given to the fine capture and tracking mechanism is calculated from the feedback amount of the tracking sensor output and the constant offset amount.   The control mode switching means determines the incident light angle from the detection output of the tracking sensor, and determines the angle deviation of the received light on the light receiving fiber coupler from the output of the received light angle deviation amount detector, thereby acquiring at the time of capture, tracking and 4. The optical space communication apparatus according to claim 1, wherein each control mode during communication is switched and set. A control mode switching means, a first switch for switching and setting a control mode at the time of communication and tracking of the coarse acquisition tracking control system;
A second switch for switching and setting a control mode at the time of capturing, tracking and communication in the fine capturing and tracking control system;
A tracking sensor angle determiner that determines an incident light angle from a detection output of the tracking sensor and sets the first switch to a control mode for communication and tracking;
A received light angle deviation amount detector for determining an angle deviation of the received light on the light receiving fiber coupler from an output of the received light angle deviation amount detector and extracting a determination output for determining tracking and communication;
An automatic switch selector for setting the second switch to a control mode at the time of acquisition, tracking or communication in response to both outputs of the tracking sensor angle determination unit and the received light angle deviation amount determination unit; The optical space communication apparatus according to claim 1, wherein the optical space communication apparatus is provided.   The pointing sensor is composed of a two-dimensional CCD, the tracking sensor is composed of a four-quadrant detector, and a light-receiving fiber coupler is arranged around the single-mode fiber and the single-mode fiber for optically coupling the received light to the receiver. The optical space communication apparatus according to any one of claims 1 to 5, wherein the optical space communication apparatus includes a multimode fiber for detecting the position of the received light. A coarse acquisition and tracking mechanism for roughly capturing the transmitted light from the counterpart station by roughly directing the light receiving unit of the transmission / reception telescope to the counterpart station by driving the gimbal in the elevation direction and the azimuth direction,
A fine capture tracking mechanism that finely captures the reception light roughly captured by the coarse capture tracking mechanism by driving the biaxial gimbal;
A coarse capture tracking mechanism gimbal angle sensor for detecting a rough capture tracking mechanism gimbal angle;
A fine capture tracking mechanism gimbal angle sensor for detecting a gimbal angle of the fine capture tracking mechanism;
A pointing sensor that detects a relative angle error with a partner station in a wide range;
An adder that adds the relative angle error detected by the pointing sensor and the gimbal angle detected by the rough capture tracking mechanism gimbal angle sensor;
Orbit prediction value that predicts and sets the relative angle of the partner station to its own station from the orbit information,
A command value at the time of capture preset as a target value for forming a fine capture and tracking control system at the time of capture,
A command value at the time of communication set in advance as a target value for forming a fine capture and tracking control system at the time of communication,
A light receiving fiber coupler that optically couples to a receiver that demodulates the received light into an electrical signal having a function of detecting the optical position of the light from the received light;
A received light angular deviation detector for calculating the angular deviation of the received light on the light receiving fiber coupler;
From the detection output of the fine capture and tracking mechanism gimbal angle sensor, a precise control target value for driving the coarse capture and tracking control mechanism is obtained so that the fine capture and tracking mechanism gimbal angle is set in the vicinity of the origin during tracking and communication. A coarse cooperative compensator;
The correction amount of the gimbal angle given to the coarse acquisition tracking mechanism is calculated from the output of the adder at the time of acquisition, the predicted trajectory value, and the feedback amount of the output of the rough acquisition tracking mechanism gimbal angle sensor. A coarse acquisition tracking compensator that calculates a correction amount of a gimbal angle to be given to the coarse acquisition tracking mechanism from a control target value from a compensator, the trajectory prediction value, and a feedback amount of an output of the coarse acquisition tracking mechanism gimbal angle sensor;
The correction value of the gimbal angle given to the fine capture tracking mechanism is calculated from the capture command value during capture and the feedback amount of the output of the fine capture tracking mechanism gimbal angle sensor, and the communication command value and the received light are calculated during communication. A fine-acquisition tracking compensator that calculates the correction amount of the gimbal angle given to the fine-acquisition tracking mechanism from the feedback amount of the output of the angular deviation detector;
An optical space communication device comprising control mode switching means for setting a control mode at the time of capture and at the time of communication. The control mode switching means determines the incident light angle from the detection output of the pointing sensor, and determines the angle deviation of the received light on the light receiving fiber coupler from the output of the received light angle deviation amount detector, so that at the time of capture and communication 8. The optical space communication apparatus according to claim 7, wherein the control mode is switched and set.   9. The adder according to claim 1, wherein the adder holds an output value at the time of prior light reception as it is when the pointing sensor cannot obtain a detection output at the time of non-light reception. The optical space communication apparatus according to the item. An image rotation detector for detecting the rotation angle of the received light generated in the internal optical system by the rotation of the coarse acquisition and tracking mechanism;
A rotation mechanism for rotating the internal optical system;
2. A rotation mechanism control circuit that drives and controls the rotation mechanism so as to cancel image rotation generated in the internal optical system in response to a detection output of an image rotation detector. Item 10. The optical space communication device according to any one of Items 9 to 9.

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