CP based time-reversal QOSTBC transmissions over frequency-selective fading channels

In this work, the encoding/decoding scheme for the cyclic prefix (CP) based time-reversal quasi-orthogonal space-time block coded (TR-QOSTBC) wireless communication systems over frequency-selective fading channels is studied. A CP based 4 times 1 TR-QOSTBC system is studied in detail, and the upper bound of the pairwise error probability (PEP) is derived. Our analysis shows that the proposed scheme can successfully exploit the multipath diversity embedded in frequency-selective fading channels. For time-reversal rotated QOSTBC (TR-ROSTBC) system, both the multipath diversity and the full spatial diversity can be achieved. With a decoupled structure, the frequency-domain optimal maximum likelihood (ML) solution and the low-complexity sub-optimal solution in a pair-wise sense are proposed. Simulation results verify our analysis and the effectiveness of the proposed solutions.