Hello KlausST,
Thank you for your reply.
For the following spectrum result that I posted before, I am using the following values.
For PAM-4,
symbol-rate is 1Gsym/s (f_sym = 1e9) so one symbol period is 1ns.
Sampling-rate is 1000GHz (Rs = 1000).
This is the time-domain of PAM-4 signal that I am using as one period in n-point dft.
It contains 100 symbols, and in each symbol there are 1000 samples of points, so total 100000 points in the dft.
View attachment 156359
For the signaling scheme that I am proposing, it uses PAM-4 signaling and PM-4 in an alternate way as below.
In this case, symbol-rate in PAM-4 UI is 1Gsym/s. In PM-4 UI, PM spacing is 0.25UI.
Therefore, minimum pulse-width of 1.25UI can be achieved.
symbol-rate is set to 1Gsym/s (f_sym = 1e9) so minimum pulsewidth is 1.25ns in this case.
Sampling-rate is 1000GHz (Rs = 1000).
This is the time-domain of the signal that I am using as one period in n-point dft.
It contains 100 symbols of PAM-4 and PM-4 each (so in total 200 symbols).
In each PAM-4 symbol, there are 1000 samples of points.
In each PM-4, each PM slice in time (0.25UI) contains 250 samples of points.
View attachment 156358
Thank you.