Iterative channel estimation for short preamble based OFDM/OQAM system

The existed preamble structure for orthogonal frequency division multiplex/offset QAM (OFDM/OQAM) system requires two zero-value guard symbols to guarantee ISI and ICI avoidance (equivalent to 3/2 complex value symbols in OFDM with cyclic prefix system), which leads to OFDM/OQAM system with low spectrum efficiency. In this paper, we shorten the preamble with 1 zero-value guard symbol to improve the spectrum efficiency. Unfortunately, the residual inter symbol interference (ISI) from neighbor symbols degrade the channel estimation performance. Therefore, we propose an iterative channel estimation method for OFDM/OQAM system to remove the residual ISI. Simulation results demonstrate that short preamble with iterative channel estimation is an effective method for OFDM/OQAM system. Furthermore, as the number of iterative time increasing, BER performance of short preamble with iterative channel estimation is approximately close to perfect channel estimation.

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