Research On Key Technologies Of Ultra High Speed Time Interleaving ADC In Optical Signal Acquisition System

As one of the most important ways of information transmission,optical fiber communication has higher and higher requirements for signal conversion rate.The key device to realize analog-to-digital conversion-Ultra-high Speed ADC has always been the research focus of academic and industrial circles.At present,almost all ultra-high speed ADCs adopt time interleaving structure,so this article mainly studies the key technologies of ultra-high speed time interleaving ADC,including:(1)The sub ADC,one of the key technologies of ultra-high speed time interleaving ADC,is deeply analyzed.For the architectures of two commonly used sub ADCs,pipelined ADC and successive approximation ADC,a comprehensive comparative analysis is carried out from the aspects of power consumption and noise,their relatively better architectures are determined,and a set of fully automatic architecture analysis and optimization software of pipelined ADC is designed,Improved work efficiency.(2)Another key technology of ultra-high speed time interleaved ADC-mismatch calibration is deeply studied.In view of the limitation that the traditional time mismatch estimation algorithm based on reference signal can only estimate the mismatch for specific reference signal,the time mismatch value is estimated by using the relationship between the absolute average value of inter channel derivative and time mismatch difference,It reduces the limitation of the traditional algorithm on the reference signal.(3)Aiming at the problem that the traditional time mismatch compensation algorithm based on Taylor series leads to calibration failure in some frequency domain,a channel combination calibration method is proposed to solve the problem of calibration direction error;In addition,in view of the computational complexity of the traditional algorithm using Lagrange interpolation to estimate the first to third derivatives of the output signal,the first derivative is used to estimate the second and third derivatives,which reduces the computational complexity.