Semiblind channel estimation for OFDM/OQAM systems assisted by zero-valued pilots

Orthogonal frequency division multiplexing (OFDM) with offset quadrature amplitude modulation (OQAM) has been considered as a potential alternative to the popular OFDM systems using cyclic prefixes (CP) for advantages in bandwidth efficiency. However, most current channel estimation methods for OFDM/OQAM require a considerable amount of pilots or preamble, which could damage such a bandwidth efficiency. In this paper, semiblind channel estimation for OFDM/OQAM systems is studied. The proposed method is based on exploiting the statistical properties of the signal and interference components in the received OQAM signal. Moreover, a scattered set of pilots of zero values is introduced to further improve channel estimation performance. Compared to a recently reported method, the proposed method shows advantages when the available received data for channel estimation is limited, making the proposed method more suitable when the channel coherence time is small. Simulation results verified the advantages of the proposed method.