A hybrid filter bank approach to analog-to-digital conversion
This paper presents a novel approach to high-speed, high-resolution analog-to-digital (A/D) conversion using a hybrid filter bank with an array of slower speed A/D converters (ADCs). The hybrid filter bank is a new class of filter bank that employs continuous-time analysis filters to allocate a frequency band to each ADC in the array and discrete-time synthesis filters to reconstruct the digitized signal. The filter bank improves the speed and resolution of the A/D conversion by reducing the effects of mismatches between the ADCs in the array. This paper presents a filter design algorithm which minimizes mean-squared reconstruction error for the M-channel hybrid filter bank. A near-perfect-reconstruction, two-channel hybrid filter bank which introduces 0.00095 dB average deviation from 0 dB distortion and -108 dB average aliasing is developed.<<ETX>>