Real-Time Adaptive Smoothing with a 1-D Nonlinear Relaxation Network in Analogue VLSI Technology

Reconstruction of given noisy data is an ill-posed problem and a computationally intensive task. Non-linear regularisation techniques are used to find a unique solution under certain constraints. In our contribution we present a parallel mixed-signal architecture which solves this non-linear problem within microseconds. By connecting all parallel cells in a circular manner it is possible to process noisy data vectors of infinite length. This is achieved by virtually shifting the non-linear adaptive filter kernel over the noisy data vector. A 1-D experimental chip has been fabricated using 0.8μxm CMOS technology. On-chip measurements are shown to agree with results from numerical simulations. Results from applying the 1-D chip to nonlinear smoothing of image data will also be given correspondence.