The adaptive filter is based on variable step size LMS method(VSSLMS),which can reduce the computation requirement and improve the convergence speed.

In order to find new algorithms and improve navigation accuracy,the paper studies the variable step-size LMS algorithm and normalized LMS algorithm based on H ∞ optimal estimation,and apply them to the INS/SMNS integrated navigation.

A sub-optimal channel estimation algorithm in orthogonal frequency division multiplexing(OFDM) system was proposed,to reduce the complexity of traditional minimum mean square error(MMSE) channel estimator,and to alleviate the performance deterioration of MMSE estimator due to the mismatch of the estimator-to-channel statistics.

Both channel and echo response can be shortened at random with a single FIR equalizer by following the minimum mean square error rule.

This technique is based on the suboptimal subspace blind minimum mean square error (MMSE) algorithm of multiuser detection.

A multi-user detection(MUD) algorithm for fast frequency hopping multiply access/multilevel frequency shift keying communication systems is proposed,based on minimum mean square error(MMSE).

On the receiver,soft-input soft-output(SISO) channel decoder is used following minimum mean square error(MMSE) soft interference cancellation detector,and the turbo-like idea is used for the iterative detect.

High computational complexity is the main problem of the minimum mean square error(MMSE)soft interference can- cellation(SIC)based multiple-input multiple-output(MIMO)Turbo receiver.