Design of space-time trellis codes with multi-H CPM signals

Abstract

Signal design for wireless data links modeled as quasi-static Rayleigh is approached using space-time trellis (STT) coding and power/bandwidth efficient multi-h phase-coded continuous phase modulation (CPM) signals. System configuration for achieving multiple-input multiple-output (MIMO) with arbitrary number of antennas at the transmitter and receiver is described. At the receiver, the received signal is modeled as a linear sum of Rayleigh faded multi-h CPM signals with additive white Gaussian noise (AWGN). The problem of recovering transmitted data from such a composite signal is addressed using the criterion of maximum likelihood sequence estimation (MLSE). The finite-state discrete-time properties of the received composite signal are exploited and using Euclidean distance criterion best STT codes are determined. Performance analysis is presented based on pair-wise error probabilities (PWEP) for all possible pairs of signals in signal-space. It is noted that PWEP is a function of signal matrix, hence on multi-h CPM, and channel gain matrix. The signal matrix corresponding to error events is presented as a function of multi-h CPM signal parameters. From this signal matrix, the rank and the minimum determinant (minimum product of eigenvalues) of STT coded multi-h CPM can be found. It is shown that for these STT codes coding gain of 1.9 dB can be achieved relative to identical coding and MSK