Baseband and Signal Conditioning

The baseband stage includes LPF, PGA, and ADC,

where the beat signal is filtered, amplitude-adjusted, and digitized for further digital processing.

1. ADC and Nyquist Frequency

Since the ADC sampling rate is fixed at 2.5 MHz,

the beat frequency signal input to the ADC is expected to be limited to within the Nyquist frequency (1.25 MHz).

To ensure good signal quality and robust radar processing, i

t is recommended to keep the beat signal bandwidth within about 30% of the Nyquist frequency,