1GHz Dual-channel High-speed Data Acquisition System Based On DSP And FPGA

As an important part of information systems, high speed data acquisition system (DAS for short) is the key link of digital signal processing, which has been widely used in radar, communications, software defined radio, remote sensing and other fields. The performance development of high speed ADC and FPGA brings more flexibility and efficiency for designing or realizing DAS. As control core in the DAS system, FPGA realizes functions such as sampling data reception, caching, detecting and transmission operation. FPGA can highly improve the adapt ability and flexibility of the system.In order to process the IF (intermediate frequency) signal in a digitized way for the speed of 1GSps, this article has completed one high speed data acquisition system based on the parallel time alternately sampling principle. After elaborating the power management of the high speed data acquisition system, the paper designs the ADC module, the FPGA module, the DSP module and the interface circuit of them separately. In the PCB design part, the article discussed the signal integrity and proposed three main factors which greatly do harm to the signals and the solution, then narrated the power complete and high speed PCB layout problems which need put great attention on. In the software design part, we describe the principle and implementation process of the DMUX module, the ping-pong buffer cache module and the external memory interface. Finally, these designs are simulated and debugged which offers results and data. The DSP section describes how to effectively read the FIFO in the FPGA, and describes the way to pass data to the host computer system for effective analysis through the PCI interface.The implement of DAS based on combination of high speed ADC, Large-scale FPGA and High-performance DSP makes the design more flexible and brings convenience to data processing and storage module extension. After simulation and debugging, it indicates that the design performance can meet the requirements of high speed data acquisition and has a good value of application.