JP3051243B2 - Transmission system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission system for emitting a jamming radio wave.

[0002]

2. Description of the Related Art FIG. 3 is a block diagram showing a conventional transmission system. In the figure, 1a and 1b are arranged at a geographical distance from each other, and two transmitting devices for transmitting signals at the same frequency, and 2 generally controls the start and stop of transmission in each of these transmitting devices 1a and 1b. Reference numeral 3 denotes a single control device for controlling, and reference numeral 3 denotes a wired transmission line for transmitting the control signal generated by the control device 2 to each of the transmission devices 1a and 1b.

In each of the transmitting devices 1a and 1b,
Reference numeral 11 denotes a signal generator for generating signals of the same frequency transmitted by the transmitting devices 1a and 1b, 12 denotes a power amplifier for amplifying the signal of the same frequency generated by the signal generator 11, and 13 denotes a power amplifier 12 It is an aerial that emits a signal of the same frequency amplified by the radio wave into space as a radio wave. Reference numeral 14 denotes a controller that controls the start / stop of the signal generator 11 in accordance with a control signal sent from the control device 2 via the wired transmission line 3.

Next, the operation will be described. The control device 2 generates a control signal for instructing the transmission devices 1a and 1b to start and stop transmission, and transfers the control signal to the transmission devices 1a and 1b via the wired transmission path 3. In each of the transmission devices 1a and 1b, the control signal is received by the respective controller 14, and the controller 14 respectively receives the control signal in accordance with the control signal.
1 is started / stopped. When activated, the signal generator 11 of each of the transmission devices 1a and 1b generates a signal having the same frequency and sends it to the power amplifier 12. The power amplifier 12 amplifies the signal and emits it from the antenna 13 as radio waves into space.

[0005] Here, the transmitting system that emits the jamming radio wave must keep its position confidential, and its apparent direction or position (hereinafter referred to as apparent direction) with respect to detection by others. It is necessary to give In this transmission system, signals having the same frequency are radiated as radio waves into space from transmitting devices 1a and 1b arranged at a geographical distance, and the respective transmitting devices 1a and 1b are synthesized by a combined wave.
By creating a certain apparent orientation that is different from the true location of the device, it hides its position from detection by others.

[0006]

Since the conventional transmission system is configured as described above, each transmission device 1a, 1
Since the electric power of the radio wave radiated from b is constant and the apparent direction created is always constant, there is a problem that the effect of concealing the position of the user from other detections is lower.

[0007] The present invention has been made to solve the above-described problems, and has as its object to obtain a transmission system that can freely create an apparent direction.

[0008]

According to a transmission system according to the present invention, a variable attenuator is arranged between a signal generator and a power amplifier of each transmission device, and a controller of each transmission device is provided in a transmission system. The variable attenuator has a function of controlling the amount of attenuation.

A transmission system according to a second aspect of the present invention transmits a control signal from a control device to each transmission device by wireless transmission.

[0010]

According to the first aspect of the present invention, the variable attenuator of each transmitting device attenuates the signal of the same frequency generated by the signal generator by the amount of attenuation set by the control of the controller, and supplies the signal to the power amplifier. By supplying, the transmission power of the radiated radio wave is controlled independently for each transmission device, and the synthetic wave can freely create an apparent direction different from the true installation position of each transmission device. Is realized.

The transmission system according to the second aspect of the present invention transmits a control signal from the control device to each transmission device by wireless transmission, thereby connecting the control device to each transmission device. A transmission system in which a transmission path is eliminated and a degree of freedom of installation of a transmission device is high is realized.

[0012]

[Embodiment 1] An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, reference numerals 1a and 1b denote transmitting devices, 2 denotes a control device, 3 denotes a wired transmission line, 11 denotes a signal generator, 12 denotes a power amplifier, and 13 denotes an antenna. Since they are the same as or equivalent to those described above, detailed description is omitted.

Reference numeral 15 is arranged between the signal generator 11 and the power amplifier 12, and attenuates the signal of the same frequency generated by the signal generator 11 by an amount of attenuation set by a controller described later. This is a variable attenuator input to the power amplifier 12. Reference numeral 16 denotes a signal generator 1 in response to a control signal sent from the control device 2 via the wired transmission line 3.
1 and the variable attenuator 1
5 is a controller different from the controller denoted by reference numeral 14 in FIG.

Next, the operation will be described. The control device 2 generates an instruction to start / stop transmission of each of the transmission devices 1a and 1b, and a control signal for specifying each transmission power, and sends the control signal to each of the transmission devices 1a and 1b via the wired transmission path 3. . In each of the transmission devices 1a and 1b, the control signal is received by the respective controller 16, and the controller 16 controls the start / stop of the signal generator 11 according to the received control signal, and controls the attenuation of the variable attenuator 15. Is set to a value corresponding to the specified transmission power.

The signal generators 11 of the activated transmitters 1a and 1b generate signals having the same frequency, and the variable attenuators 15 generate the signals according to the attenuations set by the controller 16, respectively. The signal is attenuated and sent to the power amplifier 12. The power amplifier 12 amplifies the signal and radiates it as a radio wave from the antenna 13 to space.
Radio waves are radiated from the antenna 13 of each of the transmission devices 1a and 1b with the transmission power specified by the control device 2. Therefore, the apparent direction created by the synthesized wave can be freely set by the transmission power of each of the transmission devices 1a and 1b, and the confidentiality of the own position from detection by others becomes higher.

Embodiment 2 FIG. In the first embodiment, the case where the control signal from the control device 2 to each of the transmission devices 1a and 1b is transmitted through the wired transmission path 3 may be performed by wireless transmission. FIG. 2 is a block diagram showing an embodiment of such an invention described in claim 2, which is the same,
Alternatively, the same reference numerals as those in FIG. 1 denote the corresponding parts, and a description thereof will be omitted. In the figure, reference numeral 21 denotes a transmitter for transmitting a control signal generated by the control device 2, and reference numeral 22 denotes an antenna that radiates the control signal from the transmitter 21 as radio waves into space. Reference numeral 17 denotes an antenna for receiving the radio wave by each of the transmitters 1a and 1b, and reference numeral 18 denotes a receiver for returning the radio wave received by the antenna 17 to a control signal and transferring the control signal to the controller 16.

Next, the operation will be described. The control device 2 generates an instruction to start / stop transmission of each of the transmission devices 1a and 1b, and generates a control signal for designating each transmission power, and radiates it as a radio wave from the transmitter 21 to the space via the antenna 22. The radio waves are received by the antennas 17 of the transmission devices 1a and 1b, sent to the receiver 18, returned to control signals, and sent to the respective controllers 16. The following operation is the same as in the first embodiment, and a description thereof will be omitted. Thereby, the control device 2 and each of the transmission devices 1a, 1b
Therefore, the transmission devices 1a and 1b can be arranged in a place where it is difficult to lay the wire transmission line.

[0018]

As described above, according to the first aspect of the present invention, the variable attenuator is disposed between the signal generator and the power amplifier of each transmitting device, and the amount of attenuation is controlled by the controller. The transmission power of the radiated radio wave is unique to each transmitter if the signal with the same frequency generated by the signal generator is attenuated by a predetermined amount and supplied to the power amplifier. And a transmission system capable of freely creating an apparent direction different from the true installation position of each transmitting device by the synthesized wave is obtained.

According to the second aspect of the present invention, since the control signal is transmitted from the control device to each transmitting device by wireless transmission, the control device is connected to each transmitting device. This eliminates the need for a wired transmission path, and provides an effect of obtaining a transmission system with a high degree of freedom in installing a transmission device.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of the present invention.

FIG. 2 is a block diagram showing a second embodiment of the present invention.

FIG. 3 is a block diagram showing a conventional transmission system.

[Explanation of symbols]

 1a, 1b Transmission device 2 Control device 11 Signal generator 12 Power amplifier 13 Antenna 15 Variable attenuator 16 Controller

Claims (2)

(57) [Claims] 1. A plurality of transmitting devices which are arranged at a geographical distance from each other and transmit signals at the same frequency, and transmit a control signal to each of the transmitting devices, and start and stop transmission in each of the transmitting devices. In a transmission system including a control device that comprehensively controls the transmission device, each of the transmission devices is a signal generator that generates a signal with the same frequency, and a signal with the same frequency generated by the signal generator is set. A variable attenuator that attenuates by the amount of attenuation, a power amplifier that amplifies the signal of the same frequency attenuated by the variable attenuator, and an antenna that radiates the signal of the same frequency amplified by the power amplifier into space as a radio wave And controlling the start / stop of the signal generator in response to a control signal from the control device, and controlling the attenuation of the variable attenuator. A transmission system comprising a controller for performing the transmission. 2. The transmission system according to claim 1, wherein transmission of a control signal from the control device to each of the transmission devices is performed by wireless transmission.