Information rates of the noncoherent frequency selective fading channel

This paper examines ways of improving channel estimation using successive decoding for the time varying frequency selective fading channel in a point to point wireless communication system. The channel state information (CSI) is not known a priori at either the transmitter or the receiver. The paper first presents the conventional pilot-symbol aided channel estimation (PACE) scheme and then the sequential successive decoding scheme. The conventional PACE scheme involves a big loss in achievable rates, while the sequential successive decoding scheme has a large delay. Finally, these two schemes are compared with three interleaved pilot schemes, in which interleaved codewords are decoded successively. These interleaved pilot schemes have significantly reduced delays, but still maintain good achievable rates.