Digital Modulation & Constellation

Proakis & Salehi — BPSK, QPSK, M-QAM

Modulation Scheme

Channel

Metrics

Bits per Symbol
Symbol Errors
SER
EVM (rms)
Key Tradeoff
Higher order → more bits/symbol → higher data rate
But constellation points are closer → more susceptible to noise → higher BER

BPSK: 1 bit | QPSK: 2 | 16-QAM: 4 | 64-QAM: 6