Enhanced Linear Interpolation Schemes for Chunk-Based OFDMA Uplink

Linear interpolation is often employed for chunk-based OFDMA uplink because of its low complexity and good performance. However, the linear interpolation error induced by the mismatch between the linear interpolation model and the actual channel can be detrimental to high-data-rate systems operating in high signal-to-noise-ratio (SNR) range or high mobility scenario. In this paper, enhanced linear interpolation schemes with small time-direction interpolation error are proposed, particularly for the chunk-based OFDMA uplink. Unlike the conventional linear interpolation, which is based on the assumption that the real and imaginary parts of channel coefficients are separately linearly varying, the proposed schemes are based on an interesting observation that the amplitude and phase of a communication channel are also linearly varying within a short time duration, e.g. a chunk duration. Simulation results show the proposed schemes can effectively improve the performance.