用平衡式对数域积分器实现连续小波变换

Analog Implementation of Continuous Wavelet Transform Based on Balanced Log-Domain Integrator

为满足低电压、低功耗及实时处理等应用要求的需要,提出了一种新的基于平衡式对数域积分器的连续小波变换实现方法.小波变换实现电路由冲激响应为高斯一阶导数小波的模拟滤波器构成,其传输函数用Levenbery-Marquardt非线性最小二乘法求得.滤波器以工作在甲乙类状态的平衡式对数域积分器为积木块进行设计,通过改变平衡式对数域积分器的偏置电流而实现不同尺度下的小波变换.计算机仿真结果表明了该方法的可行性.

In order to meet the application requirement for low-power, low-voltage and real-time, this paper presented an analog implementation of wavelet transform using a balanced log - domain integrator with class AB. The circuits implementing wavelet transform were composed of analog filters, whose impulse response was the first derivative of the Gaussian function. Levenbery-Marquardt nonlinear least square method was employed to obtain the transfer function of the filter. The filter design was based on balanced log-domain integrators as the main building blocks. By changing the values of the log-domain integrators bias currents, this circuit can realize various scales wavelet transform. And the validity of the proposed method was confirmed by PC simulation resuits.