Correction of Gain Mismatch for Time Interleaved Analog to Digital Converter System

For digital signal processing, an analog signal should be sampled at least at the Nyquist rate. In many applications such as radar systems and software defined radios that deal with super high frequency, required sampling rates may exceed currently available analog-to-digital converters (ADCs). To increase the sampling rate time interleaved ADC (TI-ADC) systems are often used. In TI-ADC system several ADCs are interleaved to increase the sampling rate. Ideally all ADCs in the system will have the same gain. Due to imperfection of ADCs there is a gain mismatch. The gain mismatch results in spurious peaks in the spectrum and reduces the dynamic range of the TI-ADC system. In this paper we will first explain how the gain mismatch affect to the signal spectrum. We will also devise a method to estimate the gain mismatch and correct it.