The Design And Implement Of The System Of Spread Spectrum Modulation Based On Software Radio

For the great progress in the mobile communication, the ITU advances the standard of IMT2000 as the target of the 3rd generation mobile communication system. And the most influencing and applicative communicational technologies based on CDMA are WCDMA, cdma2000, and TD-SCDMA. And then the technology of CDMA plays a very important role in the communicational technology, the technology of Spread Spectrum Communication is leading the field of communication to develop in a new way. Otherwise, the combination of the principle of Spread Spectrum with the concept of Software Radio also is a new research way in the field of communication.Based on studying and reading considerable relative literatures, the dissertation uses the DSP (Digital Signal Processor) chip of TMS320VC5402 and the DDS (Direct Digital Synthesis) chip of AD9851 to construct the hardware circuit, and designing the programs of BPSK/QPSK direct sequence spread spectrum modulation with C language based on the performance of the chips, and realizing on the hardware circuit. Through the debug of software and hardware, the performance of the spread spectrum communication hardware circuit that based on the concept of software radio has been validated, and leads to some useful results.