VLSI IMPLEMENTATION OF GRBF (Gaussian Radial Basis Function) NETWORKS

A GRBF network is designed for VLSI implementation. Building blocks of the network consist mainly of analog circuits: op-amp, multiplier, multiplying DAC (digital to analog converter), floating resistor, summer and exponentiator. Parameters of the network (center, width of the Gaussian function and output layer weights) are represented digitally for convenient interfacing. It is shown that individual GRBF units allow independent tuning of center, width and amplitude. Several network structures are simulated as function approximation examples, and the performance is verified to be satisfactory.