Log-domain implementation of analog wavelet filters

For applications requiring low-power low-voltage and real-time, a novel analog VLSI implementation of continuous Marr wavelet transform based on CMOS log-domain integrator is proposed. Marr mother wavelet is approximated by a parameterized class of function. By using a hybrid particle swarm optimization algorithm (PSO) combined with the sequential quadratic programming (SQP), the optimum parameters of this function are obtained. The circuits of implementating Marr wavelet transform are composed of analog filter whose impulse response is the required wavelet. The filter design is based on IFLF structure with CMOS log-domain integrators as the main building blocks. SPICE simulations indicate an excellent approximation of ideal wavelet.