Fractionally spaced equalization of multipath channels: a semi-blind approach

A procedure for fast identification and equalization of wireless channels is presented. Using the finite impulse response (a realistic assumption) nature of wireless channels and the cyclostationary nature of the oversampled data, a finite matrix description of the channel is derived. This structure is used to obtain channel estimates and equalizers. The procedure is called semiblind because it estimates the signal subspace blindly but gets trained on phase. This technique converges quickly and is well suited for applications where the messages are short or the channel changes rapidly such that, e.g., every frame of a TDMA (time division multiple access) system needs equalization.<>