Low Complexity Frequency Domain LMMSE Equalization for Single Carrier Systems

We discuss low complexity implementations of LMMSE equalizers for single carrier systems. There are two kinds of equalizers - symbol spaced equalizer which has relatively low computational complexity but suffers from degraded performance when the sampling phase is not optimal and fractionally spaced equalizer which has a higher computational complexity but also better performance. We propose a novel equalization scheme with performance close to that of the fractionally spaced equalizer and complexity close to that of the symbol spaced equalizer. The proposed approach is shown to give an attractive performance and complexity trade off.