We propose a new approach to recursive estimation of the parameters of finite impulse response (FIR) and infinite impulse response (IIR) non-Gaussian signals which are assumed to be generated by driving a finite-dimensional channel (system) by an independent identically distributed (i.i.d.) non-Gaussian sequence. The problem is addressed in a blind setting, i.e., only the channel output is observed, not the input to it. The signal model is allowed to be nonminimum phase, hence, the model is applicable to the problem of blind channel equalization in data communication systems. The proposed recursive parameter estimator is shown to be globally convergent, i.e., the parameter estimator converges to the true model regardless of its initialization. The proposed parameter estimator is based upon a two model decomposition approach: a spectrally equivalent minimum phase (SEMP) system in cascade with an allpass system.
Jitendra K. Tugnait,
"Adaptive filters and blind equalizers for mixed-phase channels", Proc. SPIE 1565, Adaptive Signal Processing, (1 December 1991); doi: 10.1117/12.49778; https://doi.org/10.1117/12.49778