Study And Implementation Of IF Signal Processing Platform Based On Soft-defined Radio

Traditional radio is designed for hardware and specific function. Different radio stations use different communication systems, which can not be directly interconnected, poor compatibility and high upgrade cost. The basic idea of SDR is to put the A/D and D/A converter as closely as possible to the antenna, and build a common hardware platform,then use software as much as possible to implement radio functions. It realizes different communication systems through loading different software, which only need one software module to add new communication function. SDR technology is the third technology revolution in the communication field, which has broad application prospects.The paper analyzed major indexes of the key components ADC, DAC of the SDR, and focused on the SCA standard and structural system of SDR, and made specific analysis of the advantages and disadvantages of various structural system. On this basis, it designed a SDR IF signal processing platform which was of practical value. The platform was based on the IF bandpass sampling, and divided into two parts design of baseband system and IF system. Baseband system used ARM kernel of DSP of“DaVinci”series to complete system management, and completed upper and lower frequency and baseband signal processing with FPGA. DSP kernel provided co-processing for FPGA via high-speed interface. IF system mainly used AD6645, AD9772 to realize high speed A/D and D/A converter, in addition, used CDCM7005 to design a high-quality independent clock system. Finally, it completed the design and debugging of IF signal processing platform, and designed a 2ASK modem module with System generation to validate the entire platform. The result was showed that the platform could complete IF signal processing which is of feasibility and practicality.The study in this paper provided a realization scheme for the actual development of SDR platform and a practical verification platform for the subsequent research, which would help accelerating research progress.