1. Let us analyze the NRZ-L scheme. Let X(t) denote the stochastic process that generates random NRZ-L code signals, with pulse-width T sec.
(a) Simulate the stochastic process X(n) = X(nTs) in Python, assuming independent bit stream.
(b) Compute the mean mX and Auto-correlation matrix RX, and verify (approxi-mately) whether X(n) is wide-sense stationary or not.
(c) Let d U[0, T] be a uniformly distributed RV that models a random starting
point for the PCM scheme. Let X1(t) = X(t d) denote the same NRZ-L signal with random initial delay d (begin with 0 for t 2 [0 d]). Repeat the above step with X1(n) = X1(nTs).
(d) Compute the PSD of X(n) (or/and X1(n)) for different pulse-widths T.
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