Comb type pilot aided channel estimation in space time block coded OFDM systems

The channel estimation problem in OFDM systems with transmit diversity is concerned. The estimation is based on comb type pilots in frequency domain, which can provide higher bandwidth efficiency than the training block pilots. Three different estimation schemes based on such comb type pilots are discussed in this paper: one scheme is performed in frequency domain and the other two are performed in time domain. Computational simulation shows that these estimation schemes have the appropriate performance while the time domain methods have relatively simple structure.