Research on the improvement of the time-interleaved high speed digitizer's resolution with offset dither

This paper presents the principle of improving the time-interleaved high speed digitizer's resolution with offset dither in a deterministic approach. We first derive the output signal representation of the interleaved digitizer, and then present a detailed spectrum analysis of the additional signal produced by offset difference with sinusoid input. It is found that the major power of the additional signal is located in the high frequency section, so we can filter out the additional signal to increase the system resolution. Finally, computer simulation that obtains the relationship curve between the system ENOB and the input signal frequency, is given.