Workshop V3.4.1 Demo.rarl — Cdma

# ------------------------------------------------------------ # 7. Export results # ------------------------------------------------------------ ws.export_results('3User_Rayleigh_BER.csv') ws.plot('BER_vs_SNR', export='PNG') print("Demo completed – results saved to 3User_Rayleigh_BER.csv")

# ------------------------------------------------------------ # 3. Shared channel (Rayleigh, Doppler 20 Hz) # ------------------------------------------------------------ chan = cw.blocks.Channel(model='rayleigh', doppler=20, snr_range=np.arange(0, 21, 2)) Cdma Workshop V3.4.1 Demo.rarl

# ------------------------------------------------------------ # 4. Receiver chain (matched filter + LMS equalizer) # ------------------------------------------------------------ rx_spd = cw.blocks.Despread(code_set) # common despreader eq = cw.blocks.Equalizer(type='LMS', step=0.01) dem = cw.blocks.Demodulator(mod='BPSK') err = cw.blocks.ErrorCounter() Cdma Workshop V3.4.1 Demo.rarl

ws.add_chain([rx_spd, eq, dem, err])

# ------------------------------------------------------------ # 2. Define three independent users # ------------------------------------------------------------ users = [] code_set = cw.codes.Walsh(64) # 64‑chip Walsh codes for i in range(3): src = cw.blocks.Source(data_type='binary', rate=1e6, length=2**14) # 16 kbits per packet spd = cw.blocks.Spread(code=code_set[i]) users.append((src, spd)) Cdma Workshop V3.4.1 Demo.rarl