A signal distribution circuit including an equalization circuit, a signal distribution part, an operational amplifying circuit, a feedback circuit, and a time sequence circuit. The equalization circuit is configured to collect an initial broadband signal. The signal distribution part is configured to distribute a first-stage broadband signal resulting from amplitude attenuation process to obtain a plurality of same second-stage broadband signals. The operational amplifying circuit is configured to perform amplification processing on the second-stage broadband signal obtained after distribution to obtain a third-stage broadband signal. The feedback circuit is configured to feedback the third-stage broadband signal to the equalization circuit. The time sequence circuit is configured to adjust an amplification gain of the third-stage broadband signal, and transmit the third-stage broadband signal to an analog to digital converter.