Signal relay system with reduced power consumption

A signal relay system comprising:

• a first input terminal coupled to a first connector;
• a first output terminal coupled to a second connector;
• a first signal detector, coupled to the first input terminal, and configured to detect a first wakeup signal from the first input terminal;
• a first signal repeater, coupled to the first input terminal and the first signal detector, and configured to receive a first transmission signal and to amplify and forward the first transmission signal;
• a first input terminal circuit, coupled to the first input terminal, the first signal repeater and the first signal detector, and configured to reduce impedance between the first input terminal and the first signal repeater;
• a first output terminal circuit, coupled to the first signal detector, the first signal repeater and the first input terminal circuit, and configured to reduce impedance between the first output terminal and the first signal repeater;
• a first switch coupled to the first output terminal, and configured to couple the first output terminal to the first signal repeater or the first input terminal;
• a first switch controller, coupled to the first signal detector, and configured to control the first switch according to a first detection result of the first signal detector;
• a second input terminal coupled to the second connector;
• a second output terminal coupled to the first connector;
• a second signal detector, coupled to the second input terminal, and configured to detect a second wakeup signal from the second input terminal;
• a second signal repeater, coupled to the second input terminal and the second signal detector, and configured to receive a second transmission signal and to amplify and forward the second transmission signal;
• a second input terminal circuit, coupled to the second input terminal, the second signal repeater and the second signal detector, and configured to reduce impedance between the second input terminal and the second signal repeater;
• a second output terminal circuit, coupled to the second signal detector, the second signal repeater and the second input terminal circuit, and configured to reduce impedance between the second output terminal and the second signal repeater;
• a second switch coupled to the second output terminal, and configured to couple the second output terminal to the second signal repeater or the second input terminal;
• and
• a second switch controller, coupled to the second signal detector, and configured to control the second switch according to a second detection result of the second signal detector.