JPH09257914A - Prevention device for radiation hazard - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent occurrence of radiation hazard by arranging a reception antenna at a position offset from the opening face of a transmission antenna, and eliminating a support rod. SOLUTION: When a microwave from a transmission antenna 3 is transmitted to the direction shown by the dotted line 21 other than the direction of a target 5, the microwave 4 reaches a reception antenna 12 too, and a signal is input to an input end 17 of a determination circuit 10 for transmission direction through a power head 14 and a second AGC circuit 16. The circuit 10 detects the operation of a radar transmitter 1 in this way and the signal is input to the end 17 too, which means that the microwave 4 from the antenna 3 is radiated to the direction other than the direction of a target 5. Accordingly, the circuit 10 determines that the transmission direction is abnormal, and as a result a signal is output to an output end 18 thereby operating a power interrupter 19 of the transmitter 1, thereby interrupting the power supplied from a power source 22 to stop the transmission.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a case where harmful microwaves transmitted from an antenna of a radar device are erroneously transmitted in an unintended direction, or due to reflections of ground structures or other factors, people's whereabouts, etc. The present invention relates to a radiation hazard prevention device that stops the transmission of a radar device when a microwave of a certain level or higher is irradiated.

[0002]

Radio waves used in many radars are microwaves. However, this microwave is harmful to the human body, and it is necessary to monitor whether the microwave is radiated to a direction other than the target direction, which is the original transmission direction, especially the place of a person.

FIG. 5 shows a conventional structure of this type of device. In the figure, 1 is a radar transmitter and 2 is an RF (Radio Freq) output from the radar transmitter 1.
signal), 3 is a radar transmitting antenna that receives the RF signal 2 and transmits a radar microwave 4 toward a target 5, and 6 is a combiner, which extracts a part of the RF signal 2 and attenuates it. Input to the container 7. 8 is an attenuator 7
Of the RF signal 2 and converts the RF signal 2 into a DC voltage according to its strength. 9 is the first AGC
This is a circuit and makes the output of the power head 8 a constant level. Reference numeral 10 is a transmission direction determination circuit, the first input terminal 11 of which receives the output of the first AGC circuit 9. Reference numeral 12 denotes an antenna for receiving a part of the microwave 4 radiated from the radar transmitting antenna 3, which is much smaller than the radar transmitting antenna 3. That is, the size is set so as not to interfere with the microwave 4 radiated from the radar transmitting antenna 3 toward the target 5. Further, a supporting rod 13 is connected to the radar transmitting antenna 3 at a position facing the radar transmitting antenna 3 at a predetermined interval. A power head 14 receives a reception signal 15 of the reception antenna 12, and converts the signal 15 into a DC voltage according to its strength. A second AGC circuit 16 sets the output of the power head 14 to a constant level and supplies the output to the second input terminal 17 of the transmission direction determination circuit 10. Reference numeral 18 denotes an output end of the transmission direction determination circuit 10, and an output generated from the output end 18 is supplied to the radar transmitter 1
To the power circuit breaker 19. Reference numeral 20 denotes a radiation hazard prevention device, which includes a coupler 6, an attenuator 7, a power head 8, a first AGC circuit 9, a transmission direction determination circuit 10, a power head 14, a second AGC circuit 16, and a power breaker 19. It is composed by. Reference numeral 21 indicates a radar microwave transmitted in a direction other than the target 5 due to a failure or the like. 22 is a power source of the radar transmitter 1.

Next, the operation will be described. When the radar transmitter 1 starts transmitting, the microwave 4 is transmitted from the radar transmitting antenna 3 toward the target 5. At the same time, a part of the RF signal 2 is introduced into the radiation hazard prevention device 20 from the coupler 6 and attenuated to an appropriate level by the attenuator 7, and then converted into a DC signal by the power head 8 which converts the RF signal into a DC voltage. The converted signal is converted into a constant level by the first AGC circuit 9. Then, the signal is input to the first input terminal 11 of the transmission direction determination circuit 10, and the transmission direction determination circuit 10 detects the operation of the radar transmitter 1.

[0005] Normally, the radar transmitting antenna 3 turns to face the target 5, and the microwave 4 is transmitted in the direction of the target 5. Therefore, the microwave 4 also reaches the reception antenna 12 connected to the predetermined position opposed to the radar transmission antenna 3 and the support rod 13, and passes through the power head 14 and the second AGC circuit 16 to determine the transmission direction determination circuit. A signal is input to the second input terminal 17 of the switch 10. In this way, the operation of the radar transmitter 1 is controlled by the transmission direction determination circuit 10
Is detected and the signal is also input to the second input end 17, the transmission direction determination circuit 10 determines that the transmission direction is normal, and as a result, no output signal is generated at the output end 18, and The power breaker 19 of the transmitter 1 does not operate.

By the way, when the microwave transmitted from the radar transmitting antenna 3 is transmitted in the direction indicated by the dotted line 21 other than the direction of the target 5 due to a failure or other factors, the radar transmitting antenna 3 has a predetermined opposing direction. The microwave does not reach the receiving antenna 12 installed at the position, and no signal is input to the second input end 17 of the transmission direction determination circuit 10 via the power head 14 and the second AGC circuit 16. . As described above, the fact that the signal is not input to the second input end 17 although the operation of the radar transmitter 1 is detected by the transmission direction determination circuit 10 means that the microwave 4 radiated from the radar transmission antenna 3 is It means that the radiation is emitted in a direction other than the target 5. Therefore, the transmission direction determination circuit 10 determines that the transmission direction is abnormal, and consequently outputs a signal to the output end 18. Then, the power breaker 19 of the radar transmitter 1 is activated to cut off the electric power supplied from the transmitter power source 22 to stop the transmission.

[0007]

In the conventional radiation hazard prevention device as described above, as long as the microwave 4 reaches the receiving antenna 12, even if the microwave is radiated in the other direction 21. It could not be determined to be abnormal.

Further, since the antenna 12 for receiving the microwave 4 is arranged so as to face the radar transmitting antenna 3, the receiving antenna 12 itself and the support rod 13 connecting the radar transmitting antenna 3 and the receiving antenna 12 are It also causes the microwaves 4 to diffusely reflect and irradiate the whereabouts of people with the microwaves.

The present invention has been made to solve the above-mentioned problems, and if microwaves exceeding a safe level are irradiated to a place where microwaves should not be irradiated, transmission of the radar device is immediately stopped. The present invention provides a radiation hazard prevention device that can be operated.

[0010]

Means for Solving the Problems In the first invention,
It is characterized in that the receiving antenna is installed at a position different from the position shown in FIG. 5, and further, the supporting rod for connecting the radar transmitting antenna and the receiving antenna is removed.

In the second aspect of the invention, the receiving antenna is installed at a position different from the position shown in FIG. 5, the support rod connecting the radar transmitting antenna and the receiving antenna is deleted, and the radar transmitter is operated. Is omitted, and the circuit configuration is simplified as compared with FIG.

Further, in the third invention, the receiving antenna is installed at a position different from the position shown in FIG. 5, the support rod connecting the radar transmitting antenna and the receiving antenna is deleted, and the operation of the radar transmitter is detected. In addition to simplifying the circuit configuration as compared with FIG. 5, the method for stopping the transmission of the radar device uses a method of grounding the output of the radar transmitter. .

Further, in the fourth invention, the receiving antenna is installed at a position different from the position shown in FIG. 5, the support rod connecting the radar transmitting antenna and the receiving antenna is deleted, and the operation of the radar transmitter is detected. In addition to simplifying the circuit configuration as compared with FIG. 5, the method for controlling the radar transmitter is used as a means for stopping the transmission of the radar device.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1. 1 shows the configuration of a radiation hazard prevention device according to Embodiment 1 of the present invention. In the figure, 1 to 12 and 14 to 22 are the same as those in FIG. The difference from the configuration of FIG.
Is installed at a position that does not face the radar transmitting antenna 3, that is, a position that is off the opening surface 23 of the radar transmitting antenna 3. The position deviated from the opening surface 23 is a place where microwaves should not be radiated, such as a place of a person. Further, the support rod 13 connecting the radar transmitting antenna 3 and the receiving antenna 12 is deleted.

Next, the operation will be described. When the radar transmitter 1 starts transmitting, the microwave 4 is transmitted from the radar transmitting antenna 3 toward the target 5. At the same time, a part of the RF signal 2 is introduced into the radiation hazard prevention device 20 from the coupler 6 and attenuated to an appropriate level by the attenuator 7, and then converted into a DC signal by the power head 8 which converts the RF signal into a DC voltage. The converted signal is converted into a constant level by the first AGC circuit 9. Then, the signal is input to the first input terminal 11 of the transmission direction determination circuit 10, and the transmission direction determination circuit 10 detects the operation of the radar transmitter 1.

Usually, the radar transmitting antenna 3 turns to face the target 5, and the microwave 4 is transmitted in the direction of the target 5. Therefore, the microwave 4 does not reach a place where the microwave should not be radiated, such as a person's place,
No signal is input to the second input terminal 17 of the transmission direction determination circuit 10 via the power head 14 and the second AGC circuit 16. Thus, if the transmission direction determination circuit 10 detects the operation of the radar transmitter 1 and no signal is input to the second input terminal 17, the transmission direction determination circuit 10 determines that the transmission direction is normal, As a result, no output signal is generated at the output end 18, and the power breaker 19 of the radar transmitter 1 does not operate.

By the way, when the microwave transmitted from the radar transmitting antenna 3 is transmitted in the direction shown by the dotted line 21 other than the direction of the target 5 due to a failure or other factors, the microwave 4 is also transmitted to the receiving antenna 12. After reaching, the signal is input to the second input end 17 of the transmission direction determination circuit 10 via the power head 14 and the second AGC circuit 16. Thus, the fact that the transmission direction determination circuit 10 detects the operation of the radar transmitter 1 and the signal is input to the second input end 17 also means that the microwave 4 radiated from the radar transmission antenna 3 is targeted. It means that the radiation is in directions other than 5. Therefore, the transmission direction determination circuit 10 determines that the transmission direction is abnormal, and consequently outputs a signal to the output end 18. Then, the power breaker 19 of the radar transmitter 1 is activated to cut off the electric power supplied from the transmitter power source 22 to stop the transmission.

Embodiment 2. FIG. 2 shows the configuration of a radiation hazard prevention device according to a second embodiment of the present invention. In the figure, 1 to 5, 12, 14,
19, 21, and 22 are the same as in FIG. The difference from the configuration of FIG. 5 is that the receiving antenna 12 is installed at a position not facing the radar transmitting antenna 3, that is, at a position outside the opening surface 23 of the radar transmitting antenna 3. The position deviated from the opening surface 23 is a place where microwaves should not be radiated, such as a place of a person. Further, the support rod 1 connecting the radar transmitting antenna 3 and the receiving antenna 12
3 has been deleted. Moreover, the circuit configuration of the radiation hazard prevention device 20 is different, and the configuration is greatly simplified. That is, the means for detecting the operation of the radar transmitter 1 is omitted. More specifically, it is composed of the following elements. That is, the received signal 15 of the receiving antenna 12 is received, and the received signal 15 is received with a constant amplification factor.
An RF amplifier 24 that amplifies the signal, a reference signal generator 25 that generates a reference level for safety judgment, and a signal when the output of the power head 14 exceeds the reference level for safety judgment generated by the reference signal generator 25. It is composed of a signal level determiner 26 for outputting and a power breaker 19 of the radar transmitter 1 which operates by receiving the output of the signal level determiner 26.

Next, the operation of the second embodiment will be described. When the radar transmitter 1 starts transmission, the microwave 4 is transmitted from the radar transmitting antenna 3 toward the target 5. Here, when some microwave reaches the receiving antenna 12 installed in a place where it is desired to monitor the irradiation of the microwave, the received signal 15 of the receiving antenna 12 is guided into the radiation hazard prevention device 20, and the RF amplifier 24 is provided.
Is amplified and converted into a DC voltage by the power head 14 which converts the RF signal into a DC voltage. When the output of the power head 14 exceeds the reference level for safety judgment preset by the reference signal generator 25, the signal level judge 26 outputs a signal, and the power breaker 19 of the radar transmitter 1 receives the signal. By operating, the power source 22 of the radar transmitter 1 is cut off to stop the microwave transmission from the radar transmitting antenna 3.

Embodiment 3 FIG. 3 shows the structure of a radiation hazard prevention device according to a third embodiment of the present invention. In the figure, 1 to 5, 12, 14, and 21 are the same as those in FIG. The difference from the configuration of FIG. 5 is that the receiving antenna 12 is installed at a position not facing the radar transmitting antenna 3, that is, at a position outside the opening surface 23 of the radar transmitting antenna 3. This opening surface 23
The position away from is a place where microwaves should not be applied, such as a person's whereabouts. Further, the support rod 13 connecting the radar transmitting antenna 3 and the receiving antenna 12 is deleted. Moreover, the circuit configuration of the radiation hazard prevention device 20 is different, and the configuration is greatly simplified. That is, the means for detecting the operation of the radar transmitter 1 is omitted. More specifically, it is composed of the following elements. That is, the reception signal 15 of the reception antenna 12
In response, the RF amplifier 24 that amplifies the received signal 15 with a constant amplification factor, the reference signal generator 25 that generates a reference level for safety judgment, and the output of the power head 14 are the safety generated by the reference signal generator 25. A signal level judging device 26 which outputs a signal when the judgment reference level is exceeded.
And a switch control circuit 27 that operates by receiving the output of the signal level determiner 26, an RF switch 28 that switches the path of the RF signal 2 and is controlled by the switch control circuit 27, and a dummy load 29 that grounds the RF signal 2. It is composed by.

Next, the operation of the third embodiment will be described. When the radar transmitter 1 starts transmission, the microwave 4 is transmitted from the radar transmitting antenna 3 toward the target 5. Here, when some microwave reaches the receiving antenna 12 installed in a place where it is desired to monitor the irradiation of the microwave, the received signal 15 of the receiving antenna 12 is guided into the radiation hazard prevention device 20, and the RF amplifier 24 is provided.
Is amplified and converted into a DC voltage by the power head 14 which converts the RF signal into a DC voltage. When the output of the power head 14 exceeds the reference level for safety judgment set in advance by the reference signal generator 25, the signal level judging device 26 outputs a signal, and the switch control circuit 27 receives the output signal and the RF switch 28 Control the RF signal 2
The route is switched to the dummy load 29. As a result, the microwave transmission from the radar transmitting antenna 3 is stopped.

Embodiment 4 4 shows the structure of a radiation hazard prevention device according to a fourth embodiment of the present invention. In the figure, 1 to 5, 12, 14, and 21 are the same as those in FIG. The difference from the configuration of FIG. 5 is that the receiving antenna 12 is installed at a position not facing the radar transmitting antenna 3, that is, at a position outside the opening surface 23 of the radar transmitting antenna 3. This opening surface 23
The position away from is a place where microwaves should not be applied, such as a person's whereabouts. Further, the support rod 13 connecting the radar transmitting antenna 3 and the receiving antenna 12 is deleted. Moreover, the circuit configuration of the radiation hazard prevention device 20 is different, and the configuration is greatly simplified. That is, the means for detecting the operation of the radar transmitter 1 is omitted. More specifically, it is composed of the following elements. That is, the reception signal 15 of the reception antenna 12
In response, the RF amplifier 24 that amplifies the received signal 15 with a constant amplification factor, the reference signal generator 25 that generates a reference level for safety judgment, and the output of the power head 14 are the safety generated by the reference signal generator 25. A signal level judging device 26 which outputs a signal when the judgment reference level is exceeded.
And a control circuit 29 of the radar transmitter 1 which receives the output of the signal level determiner 26 and issues a command to stop transmission to the radar transmitter 1.

Next, the operation of the fourth embodiment will be described. When the radar transmitter 1 starts transmission, the microwave 4 is transmitted from the radar transmitting antenna 3 toward the target 5. Here, when some microwave reaches the receiving antenna 12 installed in a place where it is desired to monitor the irradiation of the microwave, the received signal 15 of the receiving antenna 12 is guided into the radiation hazard prevention device 20, and the RF amplifier 24 is provided.
Is amplified and converted into a DC voltage by the power head 14 which converts the RF signal into a DC voltage. When the output of the power head 14 exceeds the reference level for safety determination preset by the reference signal generator 25, the signal level determiner 24 outputs a signal, and the control circuit 29 of the radar transmitter 1 receives the output signal. The radar transmitter 1 issues a command to stop the output, and the radar transmitter 1 stops the transmission in response to the command from the control circuit 29 to stop the microwave transmission from the radar transmission antenna 3.

By the way, in the present invention, the receiving antenna 12 is arranged on the outside surrounded by the one-dot broken line. However, this receiving antenna 12 is still a part of the radiation hazard preventing device 20, and the above-mentioned receiving It is shown that the antenna 12 can be installed at a position apart from the part surrounded by the dashed line. In addition, the receiving antenna 12
It goes without saying that it is also possible to arrange the inside of the portion surrounded by the dashed line.

[0025]

According to the present invention, the transmission of the radar device can be immediately stopped when the microwave is applied to a place where the microwave should not be applied, such as a place of a person.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a radiation hazard prevention device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a radiation hazard prevention device according to a second embodiment of the present invention.

FIG. 3 is a diagram showing a configuration of a radiation hazard prevention device according to a third embodiment of the present invention.

FIG. 4 is a diagram showing a configuration of a radiation hazard prevention device according to a fourth embodiment of the present invention.

FIG. 5 is a diagram showing a configuration of a conventional radiation hazard prevention device.

[Explanation of symbols]

1 radar transmitter, 2 RF signal, 3 radar transmitting antenna, 4 radar microwave transmitted in the direction of target 5, 5 target, 6 coupler, 7 attenuator, 8 RF
Power head for converting signal to DC voltage, 9 1st A
GC circuit, 10 transmission direction determination circuit, 11 first input end of transmission direction determination circuit, 12 microwave receiving antenna,
13 a support rod for fixing the receiving antenna 12 at a predetermined position facing the radar transmitting antenna 3, 14 RF
A power head for converting a signal into a DC voltage, a reception signal of the microwave receiving antenna 12, a second AGC 16
Circuit, 17 second input end of transmission direction determination circuit, 18
Output end of transmission direction determination circuit, 19 power supply breaker of radar transmitter 1, 20 radiation hazard prevention device,
21 microwaves transmitted in directions other than the direction of target 5, 22 transmitter power supply, 23 radar transmission antenna 3
Opening, 24 RF amplifier, 25 reference signal generator,
26 signal level determiner, 27 switch control circuit, 2
8 RF switch, 29 dummy load, 30 Control circuit for radar transmitter 1.

Claims (4)

[Claims] 1. A radar transmitter and an RF (Radio Frequency) output from the radar transmitter.
A radar transmitting antenna which receives a signal and transmits a radar microwave toward a target, a coupler which extracts a part of the RF signal and inputs it to an attenuator, and an output of the attenuator, and determines its intensity. A power head for converting to a corresponding direct current voltage, a first AGC circuit for making the output of the power head a constant level, and an antenna for receiving microwaves installed in a place where microwaves should not be irradiated. A power head for receiving a received signal from the receiving antenna and converting the received signal into a direct current voltage according to the strength, a second AGC circuit for making the output of the power head a constant level, and the first and second AGCs. A circuit for determining the direction of transmission that receives the output of the circuit, a power supply breaker for the radar transmitter that operates by receiving the output of the circuit for determining the direction of transmission, Raj instantiation hazard protection apparatus characterized by comprising and. 2. A radar transmitter and an RF (Radio Frequency) output from the radar transmitter.
A radar transmitting antenna that receives a signal and transmits radar microwaves toward a target, an antenna that receives microwaves installed in a place where microwaves should not be irradiated, and a reception signal of this receiving antenna, An RF amplifier that amplifies with a constant amplification factor, a power head that receives the output of this RF amplifier and converts it into a DC voltage according to its strength, and a safety judgment that the output of this power head is generated by a reference signal generator. A signal level determiner that outputs a signal only when the reference level is exceeded, a power breaker of the radar transmitter that operates by receiving an output signal of the signal level determiner, and a power source of the radar transmitter. Radiation hazard prevention device characterized by 3. A radar transmitter and an RF (Radio Frequency) output from the radar transmitter.
A radar transmitting antenna that receives a signal and transmits radar microwaves toward a target, an antenna that receives microwaves installed in a place where microwaves should not be irradiated, and a reception signal of this receiving antenna, An RF amplifier that amplifies with a constant amplification factor, a power head that receives the output of this RF amplifier and converts it into a DC voltage according to its strength, and a safety judgment that the output of this power head is generated by a reference signal generator. Signal level judgment device that outputs a signal only when the reference level is exceeded, a switch control circuit that operates by receiving the output signal of this signal level judgment device, and the output of the radar transmitter that is controlled by this switch control circuit. RF switch for switching the path of the R
A radiation hazard prevention device comprising a dummy load for grounding an F signal. 4. A radar transmitter and an RF (Radio Frequency) output from the radar transmitter.
A radar transmitting antenna that receives a signal and transmits radar microwaves toward a target, an antenna that receives microwaves installed in a place where microwaves should not be irradiated, and a reception signal of this receiving antenna, An RF amplifier that amplifies with a constant amplification factor, a power head that receives the output of this RF amplifier and converts it into a DC voltage according to its strength, and a safety judgment that the output of this power head is generated by a reference signal generator. Signal level determiner that outputs a signal only when the reference level is exceeded, and a control circuit of the radar transmitter that receives the output signal of the signal level determiner and issues a command to stop transmission to the radar transmitter. Radiation hazard prevention device characterized by