Transmitter redundancy for blind estimation and equalization of time- and frequency-selective channels

Joint mitigation of time- and frequency-selective fading is an important an d challenging problem in mobile communications, Relying on transmitter-indu ced redundancy, we propose novel channel estimation and symbol recovery app roaches for blind identification and equalization of time- and frequency-se lective channels, where the time variation is modeled deterministically by a basis expansion. The resulting statistical algorithm enables the usage of a single antenna, dispenses with channel disparity conditions of existing approaches, and allows channel order overestimation. In addition, new deter ministic algorithms for generalized OFDM systems are introduced that produc e reliable estimates with few data points; at high SNR's, Simulations illus trate the approaches developed.