--- Quote Start ---
yes,my ultrosonic signal has 10KHz bandwidth on a 2.5MHz carrier,and I just receive echo signal and process
it.In my system there are 30 ultrosonic transceivers,but the process flow of each one is the same.
The sample rate of A/D is 30MSPS to the echo signal.
Up to now,I have no good idea,maybe a low pass filter is ok, but I don't try it yet.Someone think DQD(digital quadrature detection) is useful.
I have no idea what way is the best for my project.
--- Quote End ---
The most efficient solution will be to use digital demodulation to complex-valued baseband and then decimate the data using a cascade of CIC filters, half-band filters, and a band shaping FIR filter. Since your sampling rate is slower than the FPGA clock rate, which could be 3x (90MHz) to 10x (300MHz) faster than the ADC rate, you can probably re-use FPGA logic via time-division multiplexing (also known as folding).
--- Quote Start ---
process flow of each one is the same.
--- Quote End ---
Are you sure its exactly the same? Most ultrasonic arrays implement beam-forming, and in that case, each signal would be independently delayed and summed to form beams (multiple beams require different per sensor delays).
Cheers,
Dave
Honored Contributor
