JPH0260236A - System for switching between transmission and reception - Google Patents

Abstract

PURPOSE:To prevent an electric amplifier and a switch from being damaged even if the timing of a transmission/reception switching signal and that of a transmission signal differs by detecting the operation voltage of a semiconductor diode switching element as a monitor signal, supplying transmission power only at a normal time and switching a system to a transmission state. CONSTITUTION:The title system is constituted with a switch circuit 1 which changes over transmission and reception, a monitor circuit 2 detecting the operation state of the switch circuit 1 and a power circuit 3. Transmission/reception switching signals A and B are supplied from a radar equipment. The monitor circuit 2 is integrated in the switch circuit 1, inputs the monitor signal which has detected the impressed voltage conditions of the semiconductor diode switching element switching a reception path in correspondence with the transmission/reception switching signals A and B and ON/OFF of the reception path from the terminals 10 and 11, monitors whether the system is in the normal state where the switching of transmission and reception is attained or not. When a monitored result is normal, the power current of the power circuit 3 which is to be supplied to the power amplifier 4 of a transmission system is transmitted. If not, switching for a transmission mode is controlled with the transmission of the power current being cut.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a transmission/reception switching system, and particularly relates to a transmission/reception switching system that switches transmission/reception in a radar device by using on/off of a microwave semiconductor diode switching element. .

[Conventional technology]

Conventionally, this type of transmission/reception switching system has been implemented with the basic configuration shown in FIG.

That is, the transmitted signal is supplied to the power amplifier 4, subjected to power amplification, and supplied to the switch circuit 1b, and the received signal is also supplied to the switch circuit 1b. The switch circuit 1b includes a semiconductor diode switching element, for example, a pin (
This device uses the switching operation of a diode (PIN) to perform switching by connecting or disconnecting the signal conduction circuit to the ground, and while receiving the transmission/reception switching signal that drives this switching from the radar device, it switches between transmission and reception and transmits. The signal is supplied to an antenna circuit (not shown), etc., and the received signal is supplied to a receiving amplifier 10.

In such a transmission/reception switching system, in particular, the generation timing of the transmission signal and the generation timing of the transmission/reception switching signal are maintained in the correct state, thereby eliminating the occurrence of destruction of the power amplifier 4 or other abnormalities due to malfunction of transmission/reception switching. Must.

FIG. 7 is a timing chart showing a comparison of the generation timings of the transmission/reception switching signal (a) and the transmission signal (b).

As shown in FIG. 7, the timing of transmission and reception is controlled so that they occur independently of each other.

Furthermore, an isolator is connected to the output terminal of the power amplifier 4 in order to prevent the power amplifier 4 from being destroyed due to malfunction of transmission/reception switching.

[Problem to be solved by the invention]

The above-mentioned conventional transmission/reception switching system has the drawback that when an isolator is not used, if a transmission signal is applied due to a malfunction of the transmission/reception switching signal, the switch circuit will be destroyed, or the transmission signal reflected in the switch circuit will destroy the power amplifier. There is. Furthermore, when an isolator is connected to the output side of the power amplifier, the circuit scale increases by the amount of the isolator, and furthermore, the loss of the transmission signal due to the isolator occurs, resulting in an increase in the circuit scale of the power amplifier.

The object of the present invention is to provide a layer reception switching method that eliminates the above-mentioned drawbacks, basically eliminates the occurrence of damage to switch circuits and power amplifiers due to malfunction, and can significantly suppress transmission power loss and increase in circuit size. Our goal is to provide the following.

[Means to solve the problem]

The transmission/reception switching method of the present invention switches between transmission and reception of a radar device by turning on/off a semiconductor diode switching element.
In the transmitting/receiving switching method that controls the semiconductor diode switching element through OFF, the semiconductor diode switching element is configured to include means for detecting the operating voltage of the semiconductor diode switching element as a monitor signal and supplying transmitting power only when the monitor signal is normal to switch to the transmitting state. .

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the transmission switching system of the present invention. The transmitting/receiving switching system of the embodiment shown in FIG. The power supply circuit 3 is configured to include a power supply circuit 3 that limits the power supply current supplied to the power supply circuit 4.

The switch circuit 1 switches between a transmission signal input through a terminal 5 and a reception signal input through a terminal 6 under the control of transmission/reception switching signals A and B input through a terminal 8.

Transmission/reception switching signals A and B are provided by the radar device, and when outputting a transmission signal as a pair, the transmission path is secured and the input circuit of the reception system is grounded, and when the reception signal is output, the output circuit of the transmission system is grounded. By grounding and securing the transmission path, the transmission and reception operations are executed independently of each other when switching between transmission and reception.

The monitor circuit 2 connects to a terminal a monitor signal that detects the applied voltage state of a semiconductor diode switching element that is built in the switch circuit and switches the receiving path and the receiving path on and off in response to the above-mentioned transmission/reception switching signals A and H. 10
．． 11 and monitors whether or not it is in a normal state where transmission/reception switching is possible. If the monitoring result is normal, the power supply current of the power supply circuit 3 to be supplied to the power amplifier 4 of the transmission system is sent out. When the power supply current is not available, the power supply current is cut off and switching to the transmission mode is controlled.

Next, the operation of each component of the embodiment shown in FIG. 1 will be explained individually.

FIG. 2 is a circuit diagram showing in detail a first embodiment of the switch circuit 1 of FIG. 1.

The switch circuit 1 shown in FIG. 2 is divided into a transmission system that receives a transmission signal from a terminal 5 and sends it to a terminal 6, and a reception system that sends a reception signal received via a terminal 6 to a terminal 7. Further, the transmitting system is provided with a supply circuit for transmitting/receiving switching signal A, the receiving system is provided with a supplying circuit for transmitting/receiving switching signal B, the transmitting system is provided with an output circuit for monitor signal A, and the receiving system is provided with an output circuit for monitor signal B. .

The transmission system that receives the transmission signal from terminal 5 is pin diode 2.
-1a, capacitors 2-2a, 2-7a, microstrip line 2-4a, and choke 2-3a.
, resistors 2-5a, 2-6a, a capacitor 2-8a for inputting the transmitting/receiving switching signal A, and an output circuit for the monitor signal A, and the receiving system includes a pin diode 2-1b, capacitors 2-2b, 2-7b, Microstrip line 2-
4b transmission path, choke 2-3b, resistor 25b, 2-
6b, a capacitor 2-8b for inputting the transmission/reception switching signal B, and an output circuit for the monitor signal B, these transmission/reception systems transmit the transmission signal via the microphone strip line,
and input the received signal.

When a negative transmission/reception switching signal A that turns off the pin diode 2-4a is received via the terminal 8, the pin diode 2-1a
is turned off, and the transmission signal is sent from the microphone strip line 2-4 to the terminal 6. In this case, the pin diode 2-1b is provided with a positive transmission/reception switching signal B having a level that turns it on, and is turned on, and the receiving system is grounded.

The operating voltage loaded on pin diode 2-1a is
The high frequency component is blocked by the choke 2-3a, and only the DC component is sent to the terminal 10 as the monitor signal A.

When receiving a received signal from terminal 6 and sending it to terminal 7,
Contrary to the case described above, the pin diode 21a is controlled by the transmission/reception switching signals A and B so that the pin diode 2-1b is turned on and the pin diode 2-1b is turned off.

Next, the operation of the monitor circuit 2 will be explained.

FIG. 3 is a circuit diagram showing the monitor circuit 2 in detail.

The monitor circuit 2 includes comparators 4-1 to 4-3, AN
In addition to the D gates 4-4 and 4-5, it is configured with a negative reference voltage and a positive reference voltage.

The purpose of this monitor circuit 2 is to check whether the switch circuit 1 is correctly switched to the transmission state by the transmission/reception switching signals A and H via the operating voltage of the pin diodes 2-1a and 2-1b. Its purpose is to provide the signal to the power supply circuit 3 as a monitor signal.

As shown in FIG. 3, the monitor circuit 3 outputs a monitor signal A to the oven and short circuit operating voltages at the time of transmission output of the pin diodes 2-1a and 2-1b in FIG.
, B are output from the terminals 10 and 11 to the comparator 4-1. and is supplied to comparator 4-2.4-3.

During transmission, the pin diode 2-1 shown in FIG.
a must be in the oven state, and a negative bias voltage that puts the pin diode 2-1a in the oven state is applied to the terminal 8 as the transmission/reception switching signal A. That is,
In this normal transmission state, the monitor signal A applied to the terminal 10 has a negative level determined by circuit constants.

The comparator 4-1 compares this with a reference voltage and outputs a high level signal when the monitor signal A is normal.

On the other hand, the monitor signal B is output as a positive voltage determined by circuit constants, and the pin diode 2-1b is in a short-circuited state. The AND gate 4-4 outputs a high level signal in this state, and the result is:

The AND gate 4-5 outputs a signal at a high level of TTL level as a monitor signal, and supplies this to the power supply circuit 3.

FIG. 4 is a block diagram showing the power supply circuit 3 in detail.

The power supply circuit 3 receives a monitor signal from the monitor circuit 2 to control the operation of the switch circuits 1, and when the switch circuit 1 shown in FIG. 2 is correctly switched to the transmitting state and the monitor signal is output. Only the output current of the power supply current generating circuit 5-2 is sent to the power amplifier 4.

In this way, malfunctions in the transmission state during transmission/reception switching can be fundamentally eliminated.

FIG. 5 is a circuit diagram showing in detail a second embodiment of the switch circuit 1 of FIG. 1. In FIG. In this switch circuit No. 5111, the pin diodes placed in the transmission and reception paths of the switch circuit in FIG.
When 2-1b is in an open state and receiving data, the control is performed in the opposite manner.

The transmission path is microstrip line 2-9C.

Capacitor 2-1.0a, pin diode 2-1a
The receiving path is a microphone strip line 2.
-9d, capacitor 2-10b, bin diode 221
b, both of which are microstrip lines 2-9
A, 9b, and an output circuit consisting of chokes 2-30 send out a transmission signal and receive a reception signal.

Chokes 2-3a, 2-3b, resistor 2-5a.

The transmission/reception switching signal input and monitor signal A, B output circuits consisting of 2-5b, 2-6a, and 2-6b are exactly the same as in the case of FIG.

Note that even if the pin diode 2-1a in FIG. 2 is short-circuited and damaged, a negative voltage will be applied to the terminal 10;
Since the bin diode 1-a is short-circuited, a current flows and the absolute value of the voltage becomes small, and the comparator 4-1 in FIG. 4 compares the voltages and outputs a monitor output signal at the LOW level of the TTL level. Similarly, if the pin diode 2-2 in Figure 2 is open and defective, ten voltages will be applied to the terminal 11, but no current will flow, so the absolute value of the voltage will increase, and the By comparing the voltage with comparator 4-2 in Figure 4, the monitor output signal is TT.
Outputs LOW level.

In this way, even if the switch 1 in FIG. 1 is damaged, the power amplifier can be prevented from being damaged.

[Effects of the Invention] As explained above, in the transmission/reception switching system, the present invention uses a monitor circuit for detecting five operating states of a switch and a monitor signal outputted from the monitor circuit to monitor whether the transmission switching operating state is correct or not. By controlling the current, it is possible to prevent damage to the power amplifier and switch even when the timing of the transmission/reception switching signal and the timing of the transmission signal are different, and it is also possible to prevent damage to the power amplifier and switch. In comparison, since it is composed of semiconductor devices, the circuit scale can be small, and there is no need to increase the scale of the power amplifier.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the transmission/reception switching system of the present invention, FIG. 2 is a circuit diagram of a first embodiment of the switch circuit 1 of the embodiment of FIG. 1, and FIG. 4 is a block diagram of the power supply circuit of the embodiment of FIG. 1; FIG. 5 is a circuit diagram of a second embodiment of the switch circuit 1 of the embodiment of FIG. 1. , FIG. 6 is a block diagram of a conventional transmission/reception switching system, and FIG. 7 is a timing chart comparing the generation timing of the transmission/reception switching signal and the transmission signal. 1, la, lb... switch circuit, 2... monitor circuit, 3... power supply circuit, 4... power amplifier. Figure 1

Claims (1)

[Claims] In a transmission/reception switching method in which switching between transmission and reception of a radar device is controlled via on/off of a semiconductor diode switching element, the operating voltage of the semiconductor diode switching element is detected as a monitor signal, and the monitor signal is detected as a monitor signal. A transmitting/receiving switching system characterized by comprising means for supplying transmitting power only during normal times to switch to a transmitting state.