Adaptive OFDM System with Limited Feedback Using Truncated Channel Impulse Response

This work presents a new adaptive orthogonal frequency division multiplexing (OFDM) system for limited feedback channels. The proposed system is designed to minimize the number of feedback bits sent to the transmitter by sending a quantized and truncated version of the estimated channel impulse response. The truncation process is performed using the assumption that the maximum delay spread is less than the cyclic prefix of the OFDM symbol, which is typically the case in most wireless OFDM systems. Monte Carlo simulation is used to evaluate the system performance in terms of throughput and bit error rate (BER) under imperfect forward and feedback channel conditions. Simulation results reveal that the proposed system outperforms state-of-the-art techniques for the same number of feedback bits.