Doubly Selective Channel Estimation for FBMC and OFDM Systems Based on MIR Correlation

Abstract

Filter Bank Multi-Carrier (FBMC) modulation based on offset quadrature amplitude modulation has superior spectral properties than Orthogonal Frequency Division Multiplexing (OFDM). However, many existing OFDM channel estimation schemes cannot be compatible with FBMC due to inherent interference. In this letter, we propose a channel estimation method based on Measured Impulse Response (MIR) correlation, which enables compatibility with arbitrary linear modulation techniques. To ensure estimation accuracy, we combine the MIR correlation values and the orthogonal projection theorem to derive extrapolation factors instead of linear extrapolation. Additionally, for FBMC, we mitigate the interference at pilot positions by adding guard symbols. Note that although the correlation values are calculated based on the measured values, it still provides a high estimation accuracy. Simulation results show that our scheme is compatible with OFDM and FBMC, and the estimation accuracy can reach –30dB.