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Application of space-time Trellis codes for multicarrier delay diversity modulation systems

This study investigates the performance of multicarrier delay diversity modulation (MDDM) systems with both cyclic delay diversity and space–time Trellis code (STTC) techniques and compares its performance with conventional MDDM systems. Deploying STTCs can allow cost efficient and flexible system deployment compared with classical MDDM systems with multiple cyclic delays. In this study, the authors’ propose MDDM systems with both cyclic delay and STTCs. The MDDM system is modelled for two and four transmit antennas. In this study, they compare the performance of the proposed MDDM systems with quadrature phase shift keying (QPSK), 8 phase shift keying (8PSK) and 16 quadrature amplitude modulation (16QAM) STTCs and compare its results with conventional MDDM systems. The noise variance of the received signals at the MDDM receiver is mathematically derived. The minimum mean square error technique for channel estimation is applied to the proposed MDDM systems. Simulation results demonstrate that the proposed MDDM systems enhance the performance of classical MDDM systems and give large coding gains compared with the classical case.