Detection for a statistically-known, time-varying dispersive channel

Detection for the statistically-known channel (SKC) is aimed at obtaining good performance in situations where our statistical knowledge of a time-varying channel is good, and where other equalization/detection schemes are either too complex to implement, or their performance is limited due to the rapidity of channel fading. By using a statistical characterization of the channel, we develop a new detector that performs maximum-likelihood sequence estimation (given the channel model) on blocks of N symbols. Both symbol-spaced (TS) and fractionally-spaced (FS) samples are used, to obtain two different detectors that are generalizations of those devised for optimal block schemes on non-dispersive channels. The detector that uses fractionally-spaced samples outperforms the detector that uses symbol-spaced samples. The performance of both appears to approach that of the corresponding known channel (KC) detector as the blocklength increases. We also numerically evaluate the SKC detector performance under conditions where the channel parameters (statistics) are incorrectly estimated, and show that the fractionally-spaced detector is fairly robust to modeling errors