Signal modulation system measuring device

The design can measure and display other parameters such as the modulation system of the measured signal output by the signal source, identify and display the modulation mode of the measured signal, and output the demodulation signal. The measurement module is composed of an automatic gain amplifier circuit, a broadband amplifier, a low-pass filter circuit, a DDS signal generation circuit, an amplification circuit, and a display circuit. The working principle of the signal modulation measuring device is that the demodulated AM signal is obtained after the spectrum is transmitted by the multiplier, and the high-frequency signal is filtered out by the low-pass filter and amplified by the fixed gain amplifier. After the amplification circuit, the output waveform is sampled by the onboard ADC of MSP432E401Y, and then the fast Fourier transform is performed to obtain various parameters, which are finally displayed on the serial screen.