Digital Modulation APSK M-APSK Demodulator Baseband M-APSK Modulator Baseband OFDM OFDM Modulator OFDM Demodulator PM BPSK Modulator Baseband BPSK Demodulator Baseband DBPSK Demodulator Baseband DBPSK Modulator Baseband DQPSK Modulator Baseband DQPSK Demodulator Baseband M-PSK Demodulator Baseband M-PSK Modulator Baseband QPSK Demodulator Baseband QPSK Modulator Baseband PAM/QAM General QAM Demodulator Baseband General QAM Modulator Baseband Rectangular QAM Modulator Baseband Rectangular QAM Demodulator Baseband