Analysis of Channel Mismatch Errors in Frequency-Interleaved ADC System

摘要

Frequency-interleaved ADC (FIADC) is less sensitive to the mismatches between channels than the time-interleaved ADC (ADC). However, channel mismatches in FIADC such as offset, gain, and timing mismatches among channel ADCs still degrade the performance of the FIADC system. This paper analyzes the channel mismatch effects in the FIADC system. Based on the analysis, we have clarified that the gain mismatch errors and timing mismatch errors result in noises with the same frequency but different phases, and only the magnitudes of noises due to the offset mismatch errors do not depend on the input frequency. The analyzed results can be used for calibration algorithms to compensate for the channel mismatch errors among the FIADC channels.