Quantization effects in the complex LMS adaptive algorithm-linearization using dither-applications

The use of dither to linearize the gradient quantizer in a digitally implemented LMS adaptive algorithm is described. In a previous paper by the authors (see ibid., vol.CAS-34, no.7, p.848-54, 1987), a theoretical model for the performance of the system was presented. Now the theory is applied to the design of dither which prevents algorithm stalling yet does not significantly effect the steady-state mean square error of the algorithm. It is demonstrated that the contribution of dither to steady-state mean square error is negligible compared to the contribution of quantization noise when the dither vector has a high-pass temporal spectrum.<
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