Channel estimation and interference suppression for space-time coded systems in frequency-selective fading channels

It is of great interest to provide high data rate services in wireless communication systems. In order to support such services, it is desirable to extend space-time (ST) coding, originally proposed for known, frequency-nonselective fading channels, to unknown, multipath channels. In this paper, we consider the problem of interference suppression for wireless TDMA (time division multiple access) systems equipped with multiple transmit antennas and receive antennas in frequency-selective fading channels. A novel scheme with space-time block coding based transmit diversity (STTD) is presented to estimate the multipath channel, coherently demodulate information symbols, and meanwhile suppress radio interference. The proposed scheme is simple to implement and able to mitigate interference of various origins, including intersymbol interference (ISI), cochannel interference (CCI), and others. Numerical examples are presented to illustrate the performance of the proposed estimator and detector in multipath Rayleigh-fading channels.