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For high data rate multiple-input multiple-output (MIMO) systems, a joint blind channel estimation and data recovery algorithm is presented for where the relative speed of the transmit/receive terminals may change. This changing speed is called manoeuvering. The blind technique is based on non-stationary independent component analysis with a generalised exponential density function to separate each source signal, and it uses particle filtering to track the time-varying channel. The presented technique also uses a hard decision switching block which adaptively selects between discrete speeds of a manoeuvering terminal. The speed can be therefore tracked within a mobile data communication link, that is, by using only the received data information signal. The performance is evaluated by simulation and is compared with optimal coherent detection as benchmark. A large degradation in system error performance is observed if the switching block is disabled within the algorithm, confirming its advantage. Moreover, to assess the impact of the presented blind channel estimation on system error performance more directly, a fair comparison with a known blind technique based on Kalman filtering and two known pilot-aided systems is presented with the assumption of non-manoeuvering terminals. Improved performance is observed using the presented technique. [ABSTRACT FROM AUTHOR]

A new blind channel estimation technique is presented for non-linear/linear equalisation in a frequency-selective Rayleigh fading channel. At each symbol interval, a decision algorithm first makes a primary data estimate based on constrained linear minimum mean square error criterion, and then this is applied to subsequent channel estimation. Channel estimates are obtained in the form of two alternative, related methods: directly from the Wiener solution or Kalman-based recursion. The former performs better but requires more values from the normalised time-correlation function. The performance is evaluated by simulation, allowing fair comparison with the benchmark of equalised coherent detection; optimal uncoded orthogonal frequency division multiplexing with perfect channel state information at the receiver; the conventional decision-directed Kalman filtering which employs channel tracking with delay; and for the special case of flat fading, an optimised, pilot symbol-assisted modulation system. [ABSTRACT FROM AUTHOR]