An all digital 8-DPSK TCM modem for land mobile satellite communications

The authors report the real-time digital implementation of an 8-DPSK trellis-coded-modulation (TCM) modem for operation on an L-band, 5 kHz-wide, land mobile satellite (LMS) channel. The model architecture, some of the signal-processing techniques used in the modem to combat the LMS channel impairments (principally multipath fading and Doppler frequency shifts) and the model performance over the AWGN (additive white Gaussian noise) channel are presented.<<ETX>>