Research on CCD video signal processing based on correlated double sampling

摘要

In CCD detection to micro signals, it is a key technique that the output noise signals of CCD must be restrained or attenuated, so that SNR (Signal-to-Noise Ratio) can be enhanced. This paper initially presents a brief description on the characteristics of CCD output signals and usual processing schemes. And then, CCD output noise characteristics being concerned, CDS (Correlated Double Sampling) is carefully analyzed. Lastly, on the basis of establishing CDS transfer function and noise analysis model, the most proper CDS scheme is employed to test the performance of restraining KTC noise and other low-frequency noises existed in CCD signals. And the results show that if only proper sample time is chosen, 2δ -CDS circuit can not only remove KTC noise, but also restrain low-frequency noises and other white noises in different degrees.