JP2005315578A - Antenna inspection method and antenna inspection system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an antenna inspection method and an antenna inspection system for efficiently determining the quality of electronic components comprising an antenna having one power feed element and a plurality of non-power feed elements with variable-capacity devices connected thereto, respectively, and determining defective products. <P>SOLUTION: A measuring instrument 2 is used for measuring physical quantities such as a reflection coefficient, input impedance, and a voltage standing wave ratio, by supplying a high-frequency signal to the power feed element 10. Control voltages are sequentially changed and impressed on the respective variable-capacity devices 12 connected to the non-power feed elements 11. Changes in the physical quantities are measured accompanying the changes in the control voltages. The quality is determined based on a relation between the changes in the control voltages and the changes in the physical quantities. Otherwis, one variable-capacity device 12 is impressed with a control voltage of a value different from one impressed on the other variable-capacity devices 12. While changing the frequency of a supplied high-frequency signal, changes in physical quantities are measured accompanying changes in the high-frequency signal. The quality is determined based on a relation between the changes in the frequency of the supplied high-frequency signal and the changes in the physical quantities. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an antenna inspection method having one feeding element and one or a plurality of parasitic elements, and an antenna inspection system to which the inspection method is applied, and more particularly to inspection of the quality of an array antenna feeding element and parasitic element. The present invention relates to an antenna inspection method and an antenna inspection system.

  Attention is focused on an electronically controlled waveguide array antenna device (hereinafter referred to as an array antenna) comprising a single feed element and a plurality of parasitic elements called parasite elements arranged at equal distances from the feed element. (For example, refer to Patent Document 1).

  FIG. 7 is a perspective view conceptually showing the array antenna. In FIG. 7, reference numeral 100 denotes an array antenna, and the array antenna 100 includes a bar-shaped feeding element 110 and a plurality of parasitic elements 120, 120,. The power feeding element 110 is disposed perpendicularly to the base 130 at the center of the base 130 in the shape of a disk, and in the position where the circumference of the circle centering on the power feeding element 110 is equally arranged on the base 130. A plurality of parasitic elements 120, 120,... Are arranged perpendicular to the base 130.

  The variable capacitance diodes (hereinafter referred to as varactors) 121, 121,... Are connected to the ends of the parasitic elements 120, 120,. By controlling this, the capacity of the varactor can be adjusted, and thereby the directivity of the array antenna 100 can be controlled. Further, by feeding a high frequency signal to the end of the power feeding element 110 on the base 130 side, the power feeding element 110 is excited, and the array antenna 100 enters the transmission mode.

  As described above, the array antenna 100 is a variable directivity antenna, and the control characteristics of the variable directivity depend on the varactors 121, 121,. Therefore, variations in performance of the varactors 121, 121,..., Abnormalities such as failures, etc. cause a poor control of the variable directivity of the array antenna 100.

  As a method for inspecting the controllability of the variable directivity of the array antenna 100, a transmission antenna that transmits electromagnetic waves to an anechoic chamber that suppresses the influence of external electromagnetic waves and the reflection of electromagnetic waves inside, and an array antenna There is a far-field measurement in which a turntable on which 100 is placed is placed and a variable directivity control is inspected with respect to an electromagnetic wave transmitted from a transmission antenna.

There is also a method of detecting continuity of the varactor by inspecting continuity of the varactor.
JP 2001-24431 A

  However, in the conventional inspection method by far-field measurement, an anechoic chamber, a transmission antenna and a turntable required for the inspection are required, and since it takes a long time for the inspection, in order to apply to the inspection of the array antenna mass-produced as a product, There is a problem that it is not efficient in terms of both cost in terms of equipment and productivity in terms of time, and it is difficult to inspect the quality of the array antenna on the mass production line. Moreover, even if an abnormality is detected in the directivity of the array antenna, it is difficult to specify which varactor is abnormal.

  Although the varactor is easily inspected, the electrical characteristics may be abnormal even if the varactor is in conduction, and the quality of the array antenna cannot be sufficiently inspected only by the continuity inspection. Further, since the varactor is connected to the parasitic element, it is difficult to directly measure the electrical characteristics.

  The present invention has been made in view of such circumstances, and is applied to each varactor using a measuring device that measures physical quantities such as a reflection coefficient, an input impedance, and a voltage standing wave ratio with respect to a high-frequency signal supplied to a power feeding element. It is efficient by measuring the change of the physical quantity accompanying the change of the control voltage or the change of the physical quantity accompanying the change of the frequency of the high-frequency signal to be supplied, and judging the quality of the antenna from the voltage dependence or frequency dependence of the physical quantity. An object of the present invention is to provide an antenna inspection method that can be applied to a mass production line and that can identify a varactor in which an abnormality has occurred, and an antenna inspection system to which the inspection method is applied.

  According to a first aspect of the present invention, there is provided a method for inspecting an antenna having one feeding element and one or a plurality of parasitic elements to which a variable capacitance device is connected, and a reflection coefficient for a high-frequency signal supplied to the feeding element. Measure the physical quantity indicating at least one of the input impedance and voltage standing wave ratio, change the control voltage applied to control the capacitance to the variable capacitance device connected to one parasitic element, and control It is characterized in that a change in physical quantity accompanying a change in voltage is measured, and the quality of the antenna is determined based on the relationship between the change in control voltage and the change in physical quantity.

  According to a second aspect of the present invention, there is provided a method for inspecting an antenna having one feeding element and a parasitic element to which a variable capacitance device is connected. In the method for inspecting an antenna, a reflection coefficient for a high-frequency signal supplied to the feeding element, input impedance, and Control that measures at least one of the voltage standing wave ratios and applies it to other variable capacitance devices as a control voltage to control the capacitance of one variable capacitance device connected to one parasitic element Apply a control voltage different from the voltage, change the frequency of the high-frequency signal supplied to the power supply element, measure the change in physical quantity accompanying the change in frequency, and based on the relationship between the change in frequency and the change in physical quantity It is characterized by determining the quality of the antenna.

  An antenna inspection system according to a third aspect of the present invention is an antenna inspection system for inspecting an antenna having a plurality of parasitic elements to which a single feed element and a variable capacitance device are connected. The antenna and the feed element of the antenna have a high frequency. A measurement means for supplying a signal and measuring a physical quantity indicating at least one of a reflection coefficient, an input impedance and a voltage standing wave ratio with respect to the high frequency signal; and a variable connected to one parasitic element of the antenna A means for causing a capacitive device to apply while changing a control voltage for controlling the capacity; a means for causing the measuring means to measure a change in physical quantity associated with a change in control voltage; and a relationship between a change in control voltage and a change in physical quantity. And a means for judging the quality of the antenna based on the above.

  An antenna inspection system according to a fourth aspect of the invention is an antenna inspection system for inspecting an antenna having a plurality of parasitic elements to which a single feeding element and a variable capacitance device are connected. A measurement means for supplying a signal and measuring a physical quantity indicating at least one of a reflection coefficient, an input impedance, and a voltage standing wave ratio with respect to the high-frequency signal; and one connected to one parasitic element of the antenna As a control voltage for controlling the capacitance of the variable capacitance device, means for applying a control voltage having a value different from the control voltage applied to the other variable capacitance device, and changing the frequency of the high-frequency signal supplied from the measurement means to the feeding element Means for causing the measuring device to measure a change in physical quantity accompanying a change in frequency, a change in frequency and an object Characterized in that it comprises a means for determining the quality of the antenna based on the relationship between the amount of change.

  In the present invention, each of the variable capacitance devices connected to the parasitic element from the voltage dependency of the physical quantity based on the relationship between the change of the control voltage and the change of the physical quantity, or the frequency dependency based on the relationship between the change of the frequency and the change of the physical quantity. By judging the quality of antennas such as variable capacity devices, it is possible to perform inspections in a short time using simple equipment, so it is possible to reduce costs and improve productivity, so efficient and mass production The present invention can also be applied to a line, and a variable capacitance device in which an abnormality has occurred can be specified.

  In the antenna inspection method and the antenna inspection system according to the present invention, as an inspection of an antenna such as an array antenna having one feeding element and a plurality of parasitic elements to which a variable capacitance device such as a variable capacitance diode is connected, feeding is performed. Apply a high-frequency signal to the element and apply it to each variable capacitance device connected to each parasitic element using a measuring device that measures physical quantities such as reflection coefficient, input impedance, and voltage standing wave ratio for the supplied high-frequency signal The control voltage is sequentially changed, the change in the physical quantity accompanying the change in the control voltage is measured, and the quality of the antenna is determined based on the relationship between the change in the control voltage and the change in the physical quantity.

  Simple equipment that covers the antenna with an electromagnetic wave absorber and connects the measuring device with a configuration that determines the quality of the antenna from the voltage dependence of such physical quantities, for example, the quality of the variable capacitance device connected to the parasitic element of the antenna The inspection can be performed in a short time, so the cost required for the inspection such as equipment cost and work cost can be suppressed, and the improvement of productivity by the short time inspection can be expected. It is possible to apply the method as well. In addition, it is possible to identify the variable capacitance device in which an abnormality has occurred by sequentially performing the process of changing the control voltage applied to one variable capacitance device on each variable capacitance device, and therefore the inspection It is possible to enhance the content, and so on.

  Furthermore, in the present invention, as an inspection of an antenna such as an array antenna, a control voltage having a value different from that of the other variable capacitance device is applied to one variable capacitance device, and the frequency of the high frequency signal supplied from the measurement apparatus is changed. A change in physical quantity accompanying a change in frequency is measured, and the quality of the antenna is determined based on the relationship between the change in frequency of the high-frequency signal to be supplied and the change in physical quantity.

  Simple equipment that covers the antenna with an electromagnetic wave absorber and connects the measuring device with a configuration that determines the quality of the antenna from the frequency dependence of such physical quantities, for example, the quality of the variable capacitance device connected to the parasitic element of the antenna The inspection can be performed in a short time, so the cost required for the inspection such as equipment cost and work cost can be suppressed, and the improvement of productivity by the short time inspection can be expected. It is possible to apply the method as well. In addition, by applying a control voltage with a different value to each variable capacitance device, it is possible to identify the variable capacitance device in which an abnormality has occurred, and therefore it is possible to enhance the contents of the inspection. Etc. have excellent effects.

  Hereinafter, the present invention will be described in detail with reference to the drawings illustrating embodiments thereof.

Embodiment 1 FIG.
FIG. 1 is an explanatory diagram conceptually showing the configuration of the antenna inspection system according to Embodiment 1 of the present invention. In FIG. 1, reference numeral 1 denotes an electronically controlled waveguide array antenna device (hereinafter referred to as an array antenna). The array antenna 1 includes a single feeding element 10 and a plurality of rod-shaped antenna elements. A plurality of parasitic elements 11-1, 11-2,..., 11-6 called parasite elements are provided at positions spaced equidistantly. The rod-shaped power feeding element 10 is disposed perpendicularly to the base 13 at the center of the disk-shaped base 13, and the circumference of a circle centering on the power feeding element 10 in the base 13 is equally distributed. A plurality of parasitic elements 11-1, 11-2,..., 11-6 having a rod shape are arranged perpendicular to the base 13 at the positions.

  A high-frequency signal is supplied to the power supply element 10 at the end of the power supply element 10 on the base 13 side, a reflected wave reflected by the supplied high-frequency signal is received by the power supply element 10, and a power value and a reflected wave of the supplied high-frequency signal are received. A measurement apparatus 2 using a network analyzer that measures a reflection coefficient obtained from a ratio to the power value of the current, an input impedance obtained using the reflection coefficient, and a voltage standing wave ratio as physical quantities is connected.

  Each of the parasitic elements 11-1, 11-2,..., 11-6 has variable capacitance devices such as variable capacitance diodes (hereinafter referred to as varactors) 12-1, 12-2, .., 12-6 are connected, and the control voltage applied to the varactors 12-1, 12-2,..., 12-6 to control the capacity of the varactors 12-1, 12-2,. A voltage control device 3 is connected to control the control. And the capacity | capacitance of a varactor can be controlled by controlling the control voltage applied to the varactors 12-1, 12-2, ..., 12-6, and thereby the feed element 10 and each parasitic element 11-1, The RF magnetic field induced in the vicinity of 11-2,..., 11-6 changes, and the directivity of the array antenna 1 is determined.

  The measuring device 2 and the voltage control device 3 are connected to an antenna inspection device 4 using a computer such as a general-purpose computer. The antenna inspection device 4 is controlled by the measurement device 2 and controlled by the measuring device 2. The obtained result is acquired, and the control voltage applied to the varactors 12-1, 12-2,..., 12-6 is controlled via the voltage control device 3. In the following description, each parasitic element 11-1, 11-2,..., 11-6 and each varactor 12-1, 12-2,. Shown as a feed element 11 and a varactor 12.

  FIG. 2 is a block diagram showing a configuration of antenna inspection apparatus 4 used in the antenna inspection system according to Embodiment 1 of the present invention. The antenna inspection device 4 reads various information from a control unit 41 such as a CPU for controlling the entire device, a recording medium such as a CD-ROM on which various information such as a computer program and data for the antenna inspection device of the present invention are recorded. An auxiliary storage means 42 such as a CD-ROM drive, a recording means 43 such as a hard disk for recording various information read by the auxiliary storage means 42, and a storage means 44 such as a RAM for storing temporarily generated information are provided. .

  Then, the computer program for the antenna inspection apparatus recorded in the recording means 43 is stored in the storage means 44 and executed by the control means 41, thereby operating as the antenna inspection apparatus 4.

  Further, the antenna inspection device 4 includes a first connection means 45 connected to the measurement device 2, a second connection means 46 connected to the voltage control device 3, an input means 47 such as a keyboard, and a display means 48 such as a liquid crystal display. .

  Next, an antenna inspection method according to Embodiment 1 of the present invention will be described. In the antenna inspection method according to the first embodiment, a high-frequency signal having a predetermined frequency is supplied to the feeding element 10 by the measuring device 2 using a network analyzer, a reflected wave with respect to the supplied high-frequency signal is received, and the supplied high-frequency signal is received. The physical quantity such as the reflection coefficient obtained from the ratio of the power value of the current and the power value of the reflected wave, the input impedance obtained using the reflection coefficient, and the voltage standing wave ratio is measured. On the other hand, the control voltage applied to one varactor 12 among all the varactors 12-1, 12-2,. Then, the change in the physical quantity accompanying the change in the control voltage is measured, and the quality of the varactor 12 that has changed the control voltage is determined based on the relationship between the change in the control voltage and the change in the physical quantity. As described above, the capacitance of the varactor 12 can be adjusted by changing the control voltage applied to the varactor 12, and the feeding element 10 and the parasitic elements 11-1, 11 can be adjusted by changing the capacitance of the varactor 12. The RF magnetic field induced in the vicinity of −2,..., 11-6 changes and affects the physical quantity of the feed element 10. Therefore, when the varactor 12 is a non-defective product, the relationship between the change in the control voltage and the change in the physical quantity, that is, the control voltage dependency of the reflection coefficient, the input impedance, and the voltage standing wave ratio is within the range of variation due to individual differences of the varactor 12. Show a certain relationship. From these facts, it can be determined that the varactor 12 in which the control voltage dependency of the physical quantity such as the reflection coefficient, the input impedance, and the voltage standing wave ratio exceeds the variation range may be defective.

  Here, various physical quantities measured by the measuring apparatus 2 will be described. When the power value of the high-frequency signal supplied to the feed element 10 is a and the power value of the reflected wave is b, the reflection coefficient Γ is expressed by the following equation 1.

Γ = b / a Equation 1
Where Γ: reflection coefficient
a: Power value of the high-frequency signal supplied to the feeding element 10
b: The power value of the reflected wave with respect to the high frequency signal supplied to the feed element 10

  Further, the input impedance Zin can be obtained by the following equation 2 using the reflection coefficient Γ obtained by the equation 1 and the impedance Zo of the feed element 10.

Zin = Zo {(1 + Γ) / (1−Γ)} (2)
However, Zin: Input impedance
Zo: impedance of the feed element 10

  The impedance Zo of the power feeding element 10 is defined by the following formula 3 using the angular frequency ω of the high frequency signal supplied to the power feeding element 10, the inductance L, the capacitance C, and the resistance R of the power feeding element 10.

Zo = R + jωL + 1 / jωC Equation 3
Where ω is the angular frequency of the high-frequency signal supplied to the feed element 10
L: Inductance of the feed element 10
C: Capacitance of the feed element 10
R: Resistance of the feed element 10
j: Imaginary unit

  Further, the voltage standing wave ratio S can be obtained by the following equation 4 using the reflection coefficient Γ obtained by the equation 1.

S = (1+ | Γ |) / (1- | Γ |) Equation 4
Where S: Voltage standing wave ratio

  FIG. 3 is a flowchart showing processing of the antenna inspection apparatus 4 according to Embodiment 1 of the present invention. In addition, the form which determines the quality of the varactor 12 based on the voltage dependence of the reflection coefficient which is one of the physical quantities measured with the measuring apparatus 2 is demonstrated here. Under the control of the control means 41, the antenna inspection apparatus 4 substitutes an initial value 0 for a variable m (m is an integer of 0 or more) associated with the varactors 12-1, 12-2,..., 12-6 (S101). Then, a control voltage initialization process for setting the control voltage applied to each varactor 12 to the initial voltage of 0 V is performed (S102).

  Then, the antenna inspection device 4 adds 1 to the variable m under the control of the control means 41 (S103), controls the voltage control device 3, and controls the control voltage Vm to be applied to control the capacity of the varactor 12-m. The value is changed at a predetermined change, for example, from 0 V to 20 V at a speed of 1 V / sec (S104), the measurement device 2 is controlled, and the reflection coefficient associated with the change in the control voltage Vm of the varactor 12-m The change of Γm is measured (S105), and the quality of the varactor 12-m is determined based on the relationship between the change of the control voltage Vm and the change of the reflection coefficient Γm (S106). In step S106, when the control voltage dependence of the reflection coefficient Γm exceeds a preset range, it is determined that the varactor 12-m may be defective. In step S106, it is described that the quality of the varactor 12-m is determined. However, the quality of all the varactors 12-1, 12-2, ..., 12-6 is determined, and the measured reflection coefficient Γm, etc. By comprehensively considering the physical quantity of the antenna element, the quality of the specific varactor 12, the quality of the feeding element 10, the quality of the antenna element such as the defect or curvature of the feeding element 10 or the parasitic element 11, the parasitic element 11 and It is possible to determine the quality of the array antenna 1 such as the quality of the connection of the varactor 12 and the quality of the contact state between the power supply element 10 or the parasitic element 11 and the base 13.

  The antenna inspection device 4 compares the variable m with the number M of the varactors 12 under the control of the control means 41 (S107), and determines that the variable m is less than the number M of the varactors 12 (S107: YES). It is determined that there is a varactor 12 that has not yet been determined to be acceptable, and the process returns to step S102, and the subsequent processing is repeated.

  If it is determined in step S107 that the variable m is equal to or greater than the number M of the varactors 12 (S107: NO), it is determined that all the varactors 12 have been determined to be acceptable, and the quality determination result is output ( S108), the process is terminated.

  FIG. 4 is a graph showing the relationship between the change in the control voltage Vm and the change in the reflection coefficient Γm obtained by applying the antenna inspection method according to the first embodiment of the present invention. FIG. 4 is a graph showing the results obtained by the processing of the antenna inspection apparatus 4 described with reference to FIG. 4, the horizontal axis represents the control voltage Vm (V) applied to the varactor 12-m, the vertical axis represents the reflection coefficient Γm (dB), and the varactors 12-1, 12-2,. 12 is a graph showing changes in the reflection coefficient Γm when the control voltage applied to 12-6 is changed from 0V to 20V. As shown in FIG. 4, the curves indicating the control voltage dependence of the varactors 12-1, 12-2, 12-3, 12-4, and 12-6 show almost the same changes although there are some variations. The curve showing the control voltage dependency of the varactor 12-5 shows a change clearly different from the other curves. Therefore, it is possible to determine whether the varactor 12 is good or bad by setting a range in which it is determined that the product is good. Instead of changing the applied voltage Vm from 0V to 20V, a range of the reflection coefficient Sm for a predetermined value, for example, 10V, 15V, and 20V, is set in advance, and the three reflection coefficients Sm are all within the predetermined range. It is also possible to determine pass / fail by determining whether or not it is contained.

Embodiment 2. FIG.
The second embodiment is a method for determining pass / fail of the array antenna 1 based on the frequency dependence of the varactor 12. Since the configuration of the antenna inspection system and the configuration of the antenna inspection apparatus 4 in the second embodiment are the same as those in the first embodiment, the first embodiment will be referred to and the description thereof will be omitted.

  Next, an antenna inspection method according to Embodiment 2 of the present invention will be described. In the antenna inspection method according to the second embodiment, the control voltage applied to one varactor 12 among all varactors 12-1, 12-2,. The measurement device 2 using a network analyzer supplies a high-frequency signal to the power feeding element 10, receives a reflected wave with respect to the supplied high-frequency signal, and supplies the power value of the supplied high-frequency signal and the power value of the reflected wave. The physical quantity such as the reflection coefficient obtained from the ratio, the input impedance obtained using the reflection coefficient, and the voltage standing wave ratio is measured. Then, the frequency of the high-frequency signal to be supplied is changed, the change in the physical quantity accompanying the change in the frequency is measured, and based on the relationship between the change in the frequency and the change in the physical quantity, the control voltage different from that of the other varactors 12 is applied. Judge the quality. When a varactor 12 to which a control voltage different from that of other varactors 12 is applied is a non-defective product, the relationship between the change in frequency and the change in physical quantity, that is, the frequency dependence of the reflection coefficient, input impedance, and voltage standing wave ratio is It shows a certain relationship within the range of variation due to individual differences. From these facts, it can be determined that the varactor 12 in which the frequency dependency of the physical quantity such as the reflection coefficient, the input impedance, and the voltage standing wave ratio exceeds the range of variation may be defective.

  FIG. 5 is a flowchart showing processing of the antenna inspection apparatus 4 according to Embodiment 2 of the present invention. In addition, the form which determines the quality of the varactor 12 based on the frequency dependence of the reflection coefficient which is one of the physical quantities measured by the measuring apparatus 2 is demonstrated here. The antenna inspection apparatus 4 substitutes an initial value 0 for a variable m (m is an integer of 0 or more) associated with the varactors 12-1, 12-2,..., 12-6 under the control of the control means 41 (S201). Then, a control voltage initialization process for setting the control voltage applied to each varactor 12 to the initial voltage of 0 V is performed (S202).

  Then, the antenna inspection device 4 adds 1 to the variable m under the control of the control means 41 (S203), controls the voltage control device 3, and applies the control voltage Vm to control the capacity of the varactor 12-m. Then, an applied voltage Va having a predetermined value is applied (S204). The applied voltage Va is, for example, the maximum voltage Vmax that can be applied to the varactor 12-m. By setting the value of the control voltage applied to the varactor 12-m as Va, A control voltage having a value different from the control voltage 0 V applied to the other varactors 12 is applied.

  In the antenna inspection device 4, the measurement device 20 is controlled based on the control of the control means 41, and the frequency f of the high-frequency signal supplied to the feeding element 10 is set to a predetermined change, for example, from 400 MHz to 700 MHz, 10 MHz / It is changed at the speed of sec (S205), the change of the reflection coefficient Γm accompanying the change of the frequency f is measured (S206), and the quality of the varactor 12-m is determined based on the relationship between the change of the frequency f and the change of the reflection coefficient Γm. Is determined (S207). In step S207, if the frequency dependence of the reflection coefficient Γm exceeds a preset range, it is determined that the varactor 12-m may be defective. As in the first embodiment, although it is described in step S207 that the quality of the varactor 12-m is determined, the quality is determined for all the varactors 12-1, 12-2,. In addition, by comprehensively considering the measured physical quantity such as the reflection coefficient Γm, it is possible to perform various pass / fail judgments regarding the array antenna 1.

  The antenna inspection apparatus 4 compares the variable m with the number M of the varactors 12 under the control of the control means 41 (S208), and determines that the variable m is less than the number M of the varactors 12 (S208: YES). It is determined that there is a varactor 12 that has not yet been determined to be acceptable, and the process returns to step S202, and the subsequent processing is repeated.

  If it is determined in step S208 that the variable m is equal to or greater than the number M of the varactors 12 (S208: NO), it is determined that all the varactors 12 have been determined to be acceptable, and the quality determination result is output ( S209), the process is terminated.

  FIG. 6 is a graph showing the relationship between the change in the frequency f and the change in the reflection coefficient Γm obtained by applying the antenna inspection method according to the second embodiment of the present invention. FIG. 6 is a graph showing the results obtained by the processing of the antenna inspection apparatus 4 described with reference to FIG. In FIG. 6, the horizontal axis represents the frequency f (MHz) of the high-frequency signal supplied to the power feeding element 10, the vertical axis represents the reflection coefficient Sm (dB), and the frequency f of the supplied high-frequency signal varies from 400 MHz to 700 MHz. The change of the reflection coefficient Γm when changing to is shown as a graph. As shown in FIG. 6, the curves indicating the frequency dependence of the varactors 12-1, 12-2, 12-3, 12-4, and 12-6 show almost the same changes although there are some variations. The curve showing the frequency dependence of the varactor 12-5 shows a clearly different change from the other curves. Therefore, it is possible to determine whether the varactor 12 is good or bad by setting a range in which it is determined that the product is good. Instead of changing the frequency f from 400 MHz to 700 MHz, a range of the reflection coefficient Γm for a predetermined value, for example, 400 MHz, 550 MHz, and 700 MHz is set in advance, and the three reflection coefficients Γm are all within the predetermined range. You may make it determine a quality by determining whether it has entered. Moreover, when all the varactors 12-1, 12-2,..., 12-6 are out of the range where they are determined as non-defective products, there is a possibility that the feeding element 10 is defective.

  In the above-described embodiment, the number of parasitic elements is six. However, the present invention is not limited to this, and the present invention can be applied to inspection of an antenna including various numbers of parasitic elements.

  Further, in the above-described embodiment, the embodiment applied to the inspection of the array antenna in which the parasitic element is arranged on the circumference of the circle having the feeding element as the center is shown. It is also possible to apply to inspection of other antennas such as a collinear array antenna in which feeding elements are arranged on a straight line.

It is explanatory drawing which shows notionally the structure of the antenna inspection system in Embodiment 1 of this invention. It is a block diagram which shows the structure of the antenna test | inspection apparatus used with the antenna test | inspection system in Embodiment 1 of this invention. It is a flowchart which shows the process of the antenna inspection apparatus in Embodiment 1 of this invention. It is a graph which shows the relationship between the change of the control voltage obtained by applying the inspection method of the antenna in Embodiment 1 of this invention, and the change of a reflection coefficient. It is a flowchart which shows the process of the antenna inspection apparatus in Embodiment 2 of this invention. It is a graph which shows the relationship between the change of the frequency obtained by applying the inspection method of the antenna in Embodiment 2 of this invention, and the change of a reflection coefficient. It is a perspective view which shows an array antenna notionally.

Explanation of symbols

1 Electronically controlled waveguide array antenna device (array antenna)
DESCRIPTION OF SYMBOLS 10 Feeding element 11, 11-1, 11-2, ..., 11-6 Parasitic element 12, 12-1, 12-2, ..., 12-6 Variable capacity device (variable capacity diode: varactor)
DESCRIPTION OF SYMBOLS 13 Base | substrate 2 Measuring apparatus 3 Voltage control apparatus 4 Antenna test | inspection apparatus 41 Control means 42 Auxiliary memory | storage means 43 Recording means 44 Memory | storage means 45 1st connection means 46 2nd connection means 47 Input means 48 Display means

Claims (4)

In the inspection method of an antenna having one feeding element and one or more parasitic elements to which a variable capacitance device is connected,
Measure a physical quantity indicating at least one of the reflection coefficient, input impedance, and voltage standing wave ratio for the high-frequency signal supplied to the feed element,
Changing the control voltage applied to the variable capacitance device connected to one parasitic element to control the capacitance;
Measure changes in physical quantities accompanying changes in control voltage,
A method for inspecting an antenna, wherein the quality of the antenna is determined based on a relationship between a change in control voltage and a change in physical quantity. In the inspection method of an antenna having one feeding element and a parasitic element to which a variable capacitance device is connected,
Measure a physical quantity indicating at least one of the reflection coefficient, input impedance, and voltage standing wave ratio for the high-frequency signal supplied to the feed element,
As a control voltage for controlling the capacity of one variable capacitance device connected to one parasitic element, a control voltage having a value different from the control voltage applied to the other variable capacitance device is applied,
Change the frequency of the high-frequency signal supplied to the feed element,
Measure the change of physical quantity with the change of frequency,
A method for inspecting an antenna, comprising: determining whether the antenna is good or bad based on a relationship between a change in frequency and a change in physical quantity. In an antenna inspection system for inspecting an antenna having a plurality of parasitic elements to which a single feeding element and a variable capacitance device are connected,
An antenna,
Measurement means for supplying a high-frequency signal to a feeding element of the antenna and measuring a physical quantity indicating at least one of a reflection coefficient, an input impedance, and a voltage standing wave ratio with respect to the high-frequency signal;
Means for applying to a variable capacitance device connected to one parasitic element of the antenna while changing a control voltage for controlling the capacitance;
Means for causing the measurement means to measure a change in physical quantity accompanying a change in control voltage;
An antenna inspection system comprising: means for determining the quality of an antenna based on a relationship between a change in control voltage and a change in physical quantity. In an antenna inspection system for inspecting an antenna having a plurality of parasitic elements to which a single feeding element and a variable capacitance device are connected,
An antenna,
Measurement means for supplying a high-frequency signal to a feeding element of the antenna and measuring a physical quantity indicating at least one of a reflection coefficient, an input impedance, and a voltage standing wave ratio with respect to the high-frequency signal;
Means for applying a control voltage having a value different from a control voltage applied to another variable capacitance device as a control voltage for controlling the capacitance of one variable capacitance device connected to one parasitic element of the antenna;
Means for changing the frequency of the high-frequency signal supplied from the measuring means to the power feeding element;
Means for causing the measurement device to measure a change in physical quantity accompanying a change in frequency;
An antenna inspection system comprising: means for determining the quality of an antenna based on a relationship between a change in frequency and a change in physical quantity.

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