Transmitter-receiver module

A transmitter-receiver module comprising:

• a transmitter-receiver switch unit having transmitter-signal port, receiver-signal port and common signal port, in which a transmitter signal given to the transmitter-signal port is sent to the common signal port at a time of transmission, and a receiver signal given to the common signal port is sent to the receiver-signal port at a time of reception;
• a first amplifier connected, at an output side thereof, to the transmitter-signal port of the transmit-receive switch unit and configured to amplify the transmitter signal;
• a comparison-drive unit including a variable attenuator connected to the input side of the first amplifier;
• a second amplifier connected, at an input side thereof, to the receiver-signal port of the transmit-receive switch unit and configured to amplify the receiver signal;
• and
• a level monitor unit monitoring a level of the receiver signal at the input side of the second amplifier,
• wherein when a result of monitoring at the level monitor unit exceeds a preliminarily set level, the variable attenuator is controlled to increase an attenuation amount.

A radar system comprising:

• a first amplifier configured to amplify a transmitter signal;
• a second amplifier configured to amplify a receiver signal;
• an antenna configured to transmit a signal amplified by the first amplifier and receive a receiver signal;
• a detection unit configured to detect the receiver signal amplified by the second amplifier;
• and
• a control unit configured to control the antenna so as to reduce a level of the signal from the antenna when the signal detected by the detection unit exceeds a predetermined level.