Channel Updating/Tacking for an OFDM-Based STBC System Over Time-Varying Channels

We consider improving the performance of orthogonal frequency-division multiplexing (OFDM)-based mobile broadband wireless communication (MBWC) systems over time-varying frequency-selective fading channels. To battle the problem related to frequency-selective fading, we can use space-time block coding (STBC) on each OFDM subcarrier. To battle the problem related to time varying as well as that related to differential modulation/detection for STBC, we can use coherent detection based on channel updating/tracking. To this end, we propose a new packet design and corresponding signal processing algorithms. With this new design, we provide an efficient method to update/track the channel change based on decision feedback aided by forward error correction coding. Simulation examples are provided to show the effectiveness of our packet design and signal processing algorithms.