Calibration technique for new-structure, two-channel hybrid filter banks ADC

Abstract

Frequency-interleaved ADC (FIADC) is less sensitive of the channel mismatches than the Time-interleaved ADC (TIADC). However, the filter bank mismatches and channel mismatches such as offset, gain and timing mismatches among FIADC still degrade the performance of the FIADC system. This paper presents a new structure of Two-channel Hybrid Filter Banks (HFB) based on power complementary pair, which only need Single-channel filtering. Based on the analysis of channel mismatches and filter bank mismatches, calibration is carried out for FIADC system. Average distortion error of 1.5639 × 10⁻⁵ db and average aliasing error of −93 db can be achieved after calibration by using Third-order analog filter and 64-length digital filters.