JP2019186611A - Wireless microphone system - Google Patents

Abstract

To provide a wireless microphone system capable of acquiring position information of a transmitter in an operation area, and adjusting a sensitivity of a reception antenna to an appropriate value on the basis of the position information of the transmitter received.SOLUTION: An antenna sensitivity setting unit 4 adjusts a reception sensitivity of an electric wave from a transmitter 1 by a reception antenna 3. An electric wave intensity detection unit is provided in each of access points AP1 to APn, and detects an electric wave intensity of the transmitter. An electric wave intensity acquisition unit 5 receives the electric wave intensity of the transmitter from each access point. A position information calculation unit 6 calculates a position of the transmitter on the basis of the electric wave intensity of the transmitter received by the electric wave intensity acquisition unit 5. An antenna sensitivity calculation unit 7 calculates the reception sensitivity of the reception antenna on the basis of a position of the transmitter calculated by the position information calculation unit, and outputs the calculated reception sensitivity to the antenna sensitivity setting unit.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a wireless microphone system that transmits and receives audio by radio waves between a microphone functioning as a transmitter and a receiver.

  For example, as shown in Patent Document 1, in order to obtain good radio wave propagation, the wire microphone system has a reception antenna of a receiver according to the size of an area where a transmitter is operated or the number of transmitters used. The sensitivity and transmitter transmission power are adjusted appropriately.

JP 2017-079359 A

  If the operating area is large, such as a stadium, in order to receive RF signals from a transmitter far away from the receiving antenna, the sensitivity of the receiving antenna must be increased or the sensitivity is high and the directivity is excellent. It is necessary to use a receiving antenna or increase the transmission power of the transmitter. However, when the sensitivity of the receiving antenna is strong or when the transmission power of the transmitter is strong, when the transmitter moves close to the receiving antenna and the RF signal input to the receiving antenna is too strong, The RF amplifier is saturated and good radio wave propagation cannot be obtained.

  To ensure good radio propagation throughout the operating area, ensure that the RF signal is not too strong even when the transmitter is close to the receiving antenna, and good radio propagation even at a distance. Must be obtained. For that purpose, not only the sensitivity of the receiving antenna and the power of the transmitter, but also the arrangement of the receiving antenna so that the transmitter does not get too close to the receiving antenna, and the directivity of the receiving antenna are used. Need to be devised.

  In particular, when the number of transmitters to be operated increases, the RF signal input to the receiving antenna tends to become strong, so that operation near the receiving antenna becomes more difficult. Also, when used near and far from the receiving antenna at the same time, there is a problem that sensitivity suppression works because the RF signal from a nearby transmitter is strong, resulting in insufficient sensitivity for a distant transmitter. The operation becomes even more difficult.

  Depending on the number of transmitters to be operated and the conditions of the operation area, the sensitivity of the receiving antenna and the power setting of the transmitter cannot be met. In that case, it is necessary to set it so that good radio wave propagation can be obtained near the receiving antenna, and to operate while moving the receiving antenna so as to follow the transmitter as the transmitter moves. For example, the burden on the operator is large.

  The present invention has been proposed in order to solve the above-described problems of the prior art. An object of the present invention is to provide a wireless microphone system capable of acquiring position information of a transmitter in an operation area and adjusting the sensitivity of a reception antenna to an appropriate value based on the acquired position information of the transmitter. It is in.

The wireless microphone system of the present invention has the following configuration.
(1) A transmitter, a receiver including an antenna that receives radio waves from the transmitter, and a plurality of access points connected to the receiver.
(2) An antenna sensitivity setting unit that is provided in the receiver and adjusts reception sensitivity of radio waves from the transmitter by the reception antenna.
(3) A radio wave intensity detector provided at each access point and detecting the radio wave intensity of the transmitter.
(4) A radio wave intensity acquisition unit that is provided in the receiver and receives the radio wave intensity of the transmitter from each access point.
(5) A position information calculation unit that is provided in the receiver and calculates the position of the transmitter based on the radio field intensity of the transmitter received by the radio field intensity acquisition unit.
(6) The reception sensitivity of the reception antenna is calculated based on the position of the transmitter provided in the receiver and calculated by the position information calculation unit, and the calculated reception sensitivity is output to the antenna sensitivity setting unit. Antenna sensitivity calculator.

The present invention also includes the following aspects.
(1) A plurality of the transmitters are arranged, the radio field intensity detection unit provided at each access point individually detects the radio field intensity of the plurality of transmitters, and the position information calculation unit is configured to transmit the plurality of transmissions. The position of the plurality of transmitters is calculated individually based on the radio field intensity of the transmitter, and the antenna sensitivity calculation unit is configured to determine the sensitivity of the receiving antenna based on the plurality of transmitter positions and a threshold value stored in advance. Calculate
(2) The threshold is determined based on a combination of a distance for reducing the receiving antenna sensitivity and the number of the transmitters existing within the distance.
(3) The radio field intensity detection unit receives the radio field intensity of the RF signal received by the reception antenna, and the position information calculation unit is based on the radio field intensity from each access point and the radio field intensity from the reception antenna. Calculate the position of the transmitter.
(4) The antenna sensitivity calculation unit calculates antenna sensitivity by adding information related to reception quality of the RF signal received by the reception antenna.

  According to the present invention, even when the transmitter has moved close to the receiving antenna, good radio wave propagation can be obtained by automatically determining the position of the transmitter.

1 is a block diagram of a wireless microphone system according to a first embodiment. The block diagram of the wireless microphone system of 2nd Embodiment.

[1. First Embodiment]
Hereinafter, a first embodiment of the present invention will be specifically described with reference to the drawings. In this embodiment, the sensitivity of the receiving antenna is adjusted according to the position of the transmitter closest to the receiver.
(1) Configuration As shown in FIG. 1, the wireless microphone system of this embodiment includes one or more transmitters 1 and receivers 2, a reception antenna 3 provided in the receiver 2, and a receiver 2. A plurality of connected access points AP1 to APn are provided. In FIG. 1, only the transmitter 1 closest to the receiver 1 is shown.

  In recent years, in wireless microphone systems, those having a function of setting the transmitter 1 main body by an external remote between the access points AP1 to APn or the receiver 2 have become mainstream. For this external remote communication, for example, 2.4G band IEEE802.15.4 standard wireless communication, Bluetooth (registered trademark) communication, or the like is used. Each access point AP1 to APn is distributed and provided in various places in the area where the transmitter 1 is arranged, and radio wave intensity detection for detecting the intensity of an external remote radio wave transmitted from the transmitter 1 arranged in the area. Part (not shown). The receiver 2 and the radio wave intensity detectors of the access points AP1 to APn are connected by a dedicated signal line or a network such as a wired LAN.

  The receiver 2 is provided with an antenna sensitivity setting unit 4 that sets the reception sensitivity of the reception antenna 3. The receiver 2 is provided with a radio wave intensity acquisition unit 5, a position information calculation unit 6, and an antenna sensitivity calculation unit 7. The radio field intensity acquisition unit 5 is connected to each access point AP1 to APn, and the radio field intensity received by the radio field intensity detection unit of each access point AP1 to APn with respect to the transmitter 1 is input. The position information calculation unit 6 calculates the position in the area of the transmitter 1 closest to the receiver 2 based on the strength of the radio wave received from each access point AP1 to APn. In addition, the position of the receiver 2 in the area is stored in advance, and the distance between the transmitter 1 and the receiver 2 is calculated based on the position of the receiver 2 and the position of each receiver 2 in the area. To do.

  The antenna sensitivity calculation unit 7 calculates the reception sensitivity for the transmitter 1 based on the distance between the transmitter 1 and the receiver 2 calculated by the position information calculation unit 6. That is, in the wireless microphone system, the operation area (specifically, the minimum distance from the receiving antenna 3, specifically, the number of transmitters 1 used simultaneously, the transmission power of the transmitter 1, and the sensitivity of the receiving antenna 3). Estimated maximum distance). The antenna sensitivity calculation unit 7 saves information on this predetermined guideline in its own internal or external storage device. When the antenna sensitivity calculation unit 7 receives the position information of the transmitter 1 from the position information calculation unit 6, the antenna sensitivity calculation unit 7 determines whether or not the position information is within an operation area stored in advance.

  The receiver 2 is provided with a display unit 8. The display unit 8 displays the radio wave intensity information from the access points AP1 to APn, the calculated position information of the transmitter 1, and the sensitivity setting information of the receiving antenna 3.

(2) Operation The operation of the present embodiment is as follows.
When a transmitter is arranged in the operation area, external remote communication signals and the like are transmitted and received between the transmitter and the plurality of access points AP1 to APn. The radio wave intensity detectors provided in the access points AP1 to APn detect the intensity of radio waves received from the transmitter, and transmit the information to the receiver 2 via the network. The radio field intensity acquisition unit 5 of the receiver 2 transmits the radio field intensity received from the plurality of access points AP1 to APn to the position information calculation unit 6 together with the ID of each access point.

  The position information calculation unit 6 calculates in which area of the operation area the transmitter 1 exists based on the information on the radio field intensity from each of the access points AP1 to APn. The position of the transmitter 1 obtained by the position information calculation unit 6 is sent to the antenna sensitivity calculation unit 7. The antenna sensitivity calculation unit 7 calculates an appropriate value of the sensitivity of the reception antenna 3 from the calculated position information of the transmitter 1, sends setting information to the antenna sensitivity setting unit 4, and the sensitivity of the reception antenna 3 is set. That is, when the transmitter 1 is close to the receiving antenna 3 by an appropriate distance or more, an appropriate value necessary to reduce the sensitivity of the receiving antenna 3 according to the distance between the transmitter 1 and the receiving antenna 3. Is transmitted to the antenna sensitivity setting unit 4. By doing so, the sensitivity of the receiving antenna 3 is reduced, and unnecessary sensitivity suppression caused by a strong RF signal is prevented.

  In the present embodiment, when a plurality of transmitters 1 are arranged in the operation area, each access point AP1 to APn associates the radio wave intensity of each transmitter 1 with the ID of each transmitter 1. Receive. The position information calculation unit 6 calculates the position of each transmitter 1 and sends the position of the transmitter 1 closest to the receiver 2 to the antenna sensitivity calculation unit 7. The antenna sensitivity calculation unit 7 calculates an appropriate value of the sensitivity of the reception antenna 3 from the position information of the transmitter 1 closest to the receiver 2 and transmits the calculated value to the antenna sensitivity setting unit 4.

(3) Effects According to the present embodiment, the following effects are exhibited.
(1) Conventionally, in a situation where setting of the receiving antenna 3 is difficult, such as when the operating area of the wireless microphone is wide and the number of operating units is large, the operator determines the position and orientation of the receiving antenna 3 according to the operating position of the transmitter 1. Was manually adjusted. On the other hand, in this embodiment, the reception sensitivity is automatically adjusted to an appropriate reception sensitivity based on the position information of the transmitter 1. As a result, not only the burden on the operator is reduced, but also deterioration of radio wave propagation due to unexpected movement of the transmitter 1 can be prevented, and a high-quality wireless microphone can be operated.

(2) By preparing a plurality of access points AP1 to APn for external remote in the operation area, depending on the radio field strength between each access point AP1 to APn and the transmitter, for example, to which position in the operation area by three-point surveying It is possible to grasp whether a transmitter exists. In particular, since the access points AP1 to APn are provided with transmission / reception means for the external remote of the transmitter 1, the external remote radio wave intensity received by APn from each access point AP1 is used as it is. The position can be determined. Therefore, a dedicated means such as GPS for determining the position of the transmitter 1 is unnecessary, and the system configuration may be simple.

[2. Second Embodiment]
A second embodiment of the present invention will be described with reference to FIG. In the present embodiment, a plurality of transmitters 1a to 1n are arranged at different positions in the same area. The receiving antenna 3 receives the radio waves of the plurality of transmitters 1a to 1n at a time. Therefore, the sensitivity of the receiving antenna 3 set by the antenna sensitivity setting unit 4 is not set according to the position of each transmitter 1a to 1n, but the number of transmitters 1a to 1n near the receiving antenna 3. Is set according to

  In the present embodiment, each of the access points AP1 to APn receives the radio wave intensity of each of the transmitters 1a to 1n and the ID of each of the transmitters 1a to 1n, and receives the received radio wave intensity acquisition unit 5 of the receiver 2. Send to. The position information calculation unit 6 calculates the positions of the transmitters 1a to 1n based on the received radio wave strengths from the transmitters 1a to 1n at the access points AP1 to APn, and transmits the calculated positions to the antenna sensitivity calculation unit 7. In the antenna sensitivity calculation unit 7, according to a threshold value that is stored in advance, for example, a threshold value that is determined based on a combination of a distance for reducing the reception antenna sensitivity and the number of transmitters existing within the distance. The value of the sensitivity of the receiving antenna 3 is calculated.

  For example, when many transmitters 1a to 1n are close to the receiving antenna 3, the sensitivity of the receiving antenna 3 is kept low. When many transmitters 1a to 1n are far away, the sensitivity of the receiving antenna 3 is increased. In the case of simultaneous use near and far, the sensitivity of the receiving antenna 3 is adjusted so that the RF amplifier of the receiving circuit has power that does not saturate from the near number and the far number. Or the average distance of each transmitter 1a-1n is simply calculated | required, and when this average distance exceeds the threshold stored beforehand, the sensitivity of the receiving antenna 3 may be reduced.

  In the present embodiment having such a configuration, even if a plurality of transmitters 1a to 1n are arranged in the same area, the sensitivity of the receiving antenna 3 depends on the distance and the number of the transmitters 1a to 1n. Can be set appropriately. In particular, in the present embodiment, when the radio waves of the plurality of transmitters 1a to 1n are received by one receiving antenna 3, the RF amplifier of the receiving circuit is not saturated and abnormal sound is generated from the receiver 2. There are no advantages. In addition, even when the transmitter is arranged in a wide area such as an arena or a golf course and the number of transmitters is large, appropriate sensitivity of the receiving antenna 3 can be obtained.

[3. Other Embodiments]
The present invention is not limited to the above embodiment, and includes other embodiments as follows, for example.
(1) In the wireless microphone system that can monitor the reception quality of the RF signal received by the reception antenna 3, the sensitivity setting of the reception antenna 3 can be set with higher accuracy by using information related to reception quality such as a reception error rate together. You may do it. In other words, when the reception error rate is used in combination, when the error rate of the transmitter 1 near the reception antenna 3 tends to increase, it is determined that the RF signal input to the reception antenna 3 is too strong and the reception antenna 3 Decrease sensitivity. On the other hand, when the error rate of the transmitter 1 far from the receiving antenna 3 tends to increase, it is determined that the sensitivity is insufficient and the sensitivity of the receiving antenna 3 is increased. As an error check method for received data, transmission data is digitized to provide redundancy, whereby data errors are detected and corrected on the receiving side. As a redundancy method, a vertical parity check method, a horizontal parity check method, a Hamming code method, a CRC method, a Reed-Solomon code method, a convolutional code method, a Viterbi decoding method, a turbo code method, and the like can be appropriately employed.

(2) In the first embodiment, each calculation unit 6, 7 is provided in the receiver 2, but another device such as a personal computer provided outside the receiver 2 is prepared, and each calculation unit 6, 6 is provided on the other device. 7 may be provided.

(3) The access points AP1 to APn and the receiver 2 can be connected wirelessly in addition to being connected by wire as shown in the figure.

(4) When a plurality of transmitters 1a to 1n are arranged in the same area, a dedicated reception antenna 3 is provided for each transmitter 1a to 1n, and each transmitter calculated by the position information calculation unit 6 is used. The sensitivity of the dedicated receiving antenna 3 can also be controlled by the antenna sensitivity setting unit 4 according to the distance between 1a to 1n and the receiving antenna 3.

(5) In a general wireless microphone system, the radio wave intensity of the RF signal received by the receiving antenna 3 is always grasped on the receiver 2 side. Therefore, the sensitivity adjustment of the receiving antenna 3 is adopted in each embodiment. In addition to the position information from the radio wave intensity by the plurality of access points AP1 to APn, information on the RF signal intensity of the receiver 2 may be used in combination. That is, as shown by the arrows in each figure, the RF signal from the transmitter 1 received by the receiving antenna 3 is input to the radio field intensity acquisition unit 5 in FIGS. The position of the receiver 2 is specified in consideration.

(6) As the antenna sensitivity setting unit 4, in addition to the one that adjusts the intensity of the radio wave received by the receiving antenna 3 by an attenuation circuit or the like, in the case of the receiving antenna 3 having directivity, the antenna sensitivity setting unit 4 depends on the position of the transmitter 1. A device that adjusts the reception sensitivity by changing the direction of the reception antenna 3 can be used.

DESCRIPTION OF SYMBOLS 1,1a-1n ... Transmitter 2 ... Receiver 3 ... Reception antenna 4 ... Antenna sensitivity setting part 5 ... Radio wave intensity acquisition part 6 ... Position information calculation part 7 ... Antenna sensitivity calculation part 8 ... Display part

AP1-APn ... access point

Claims (5)

In a wireless microphone system including a transmitter, a receiver including an antenna that receives radio waves of the transmitter, and a plurality of access points connected to the receiver,
An antenna sensitivity setting unit that is provided in the receiver and adjusts reception sensitivity of radio waves from the transmitter by the reception antenna;
A radio wave intensity detector provided at each access point for detecting the radio wave intensity of the transmitter;
A radio field intensity acquisition unit provided in the receiver for receiving the radio field intensity of the transmitter from each access point;
A position information calculation unit that is provided in the receiver and calculates the position of the transmitter based on the radio field intensity of the transmitter received by the radio field intensity acquisition unit;
Antenna sensitivity calculation that is provided in the receiver, calculates the reception sensitivity of the reception antenna based on the position of the transmitter calculated by the position information calculation unit, and outputs the calculated reception sensitivity to the antenna sensitivity setting unit And
A wireless microphone system characterized by comprising: A plurality of the transmitters are arranged,
The radio field intensity detector provided in each access point individually detects the radio field intensity of the plurality of transmitters,
The position information calculation unit individually calculates the positions of the plurality of transmitters based on the radio field intensity of the plurality of transmitters,
The wireless microphone system according to claim 1, wherein the antenna sensitivity calculation unit calculates the sensitivity of the reception antenna based on a plurality of transmitter positions and a threshold value stored in advance.   The wireless microphone system according to claim 2, wherein the threshold value is determined based on a combination of a distance for reducing receiving antenna sensitivity and the number of the transmitters existing within the distance.   The radio field intensity detecting unit receives the radio field intensity of the RF signal received by the receiving antenna, and the position information calculating unit is based on the radio field intensity from each access point and the radio field intensity from the receiving antenna. The wireless microphone system according to claim 1, wherein the position of the wireless microphone is calculated.   The wireless microphone system according to any one of claims 1 to 4, wherein the antenna sensitivity calculation unit calculates antenna sensitivity by adding information related to reception quality of an RF signal received by the reception antenna.

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