Wideband Signal High Accuracy Sampling And Signal Reconstruction Using Multi-Channel Method

This paper presents the algorithms of wideband signal Multi-channel high accuracy sampling and signal reconstruction, in which both the arithmetic design and the simulation results are included. The algorithms of wideband signal high accuracy sampling and real-time reconstruction have been realized based on DSP system. Wideband signal high accuracy sampling and signal reconstruction are the key technique of wideband digital receiver and high-accuracy instrument (digital filter and spectrum analyzer) in modern communication system and radar system. In DSP systems, the technique of wideband signal high accuracy sampling is often used. However ADC can not take sampling rate and accuracy into consideration, and high accuracy sampling is very difficult with a single ADC when signal bandwidth is very wide. In order to settle the dilemma between sampling rate and bandwidth, sampling rate and conversion accuracy, this paper studies through time domain multi-channel sampling method and frequency domian multi-channel sampling method and discusses about how to solve the problem of wideband signal high accuracy sampling and real-time reconstruction. In time domain multi-channel sampling method, wideband signal are used to carry out sampling at different times in several channels, aiming to reduce the requirement for sampling rate and to improve sampling accuracy. In frequency domain multi-channel sampling method, the wideband signal is divided into several narrow-band subband signals, each subband signal is sampled by a low sampling rate but high accuracy ADC. Then using these sampling data of subband signals to reconstruction signal through the process of interpolation and anti-imaging filtering. After completing the above procedures, high sampling of the original wideband analog signal is realized. Computer simulation results have shown that both time domain multi-channel sampling method and frequency domain multi-channel sampling method can reduce spectrum distortion effectively and realize signal high accuracy sampling and real-time reconstruction.