| In recent years, the digital system field integration technology developed rapidly, especially the FPGA, which not only realized miniaturization, low power consumption and high reliability of the signal processing system, also as its flexible design of System-on-a-Programmable-Chip(SOPC) based on large-scale FPGA, It is replacing ASIC on the market. In the traditional general signal processing systems, DSP is used as the core, but its reconfiguration is not strong, FPGA solve this problem. Most existing FPGA integrated DSP module and combining with a strong signal parallel processing characteristics on FPGA, which make the disparity of signal processing ability between FPGA and DSP reduced to a little. Therefore, the operability of FPGA as processing core used in general signal processing system is a strong.A general real-time signal processing system based on a multi-FPGA was designed and completed by author. The system uses four XC3SD1800A as the processing core, and DDR2 SDRAM high-speed real-time data storage. The system architecture is separated to core board,bottom board and application board, by which the platform can be collocated flexibly according to actual demands. LVDS (low-voltage differential signaling) technology is used among core boards, which allows data transferred stability on a very high rate.Based on selected FPGA, the paper explains and validates the particular LVDS High-speed data channel interface and DDR2 memory interface which determines the performance of the system.Due to the high speed digital design, the design and analysis of signal integrality is very important. The author gives impedance control, PCB stack, PCB placement and routing constraints as well as completes debugging and Drawing of PCB according to experience.Power is an integral part of system design, its integrity is considered and solution is described in the article.Combining with the core board and bottom board, the author completed hardware interface design of the application board such as video image capture module, USB module; audio module, LCD and LED matrix module, some parts of interface are verified at the same time.Through testing, the general-purpose signal processing platform works well with the capabilities of real-timing, generality, expansibility, and reconfiguration. It meet high speed and real-time request in current signal processing and can be widely used in the field of real-time signal processing. By the development of this system, a solid foundation for further research of systems of general-purpose, real-time signal processing is established. |
