Research And Implementation Of ZIF DSSS Communication In Short Distance

Spread Spectrum Communcation (SSC) develops fastly in military communication applications. It owns a lot of advantages that other communication systems do not have. With the advancement of the Spread Spectrum Communcation technology, it is gradually applied more and more widly in civil communication.This dissertation foucuses on the short-distance ZIF DSSS design, including hardware and baseband receiver algorithm research and implementation.Firstly this paper expatiates the principle of SSC and ZIF(Zero-intermediate frequency), and mainly analyses DSSS(Direct-sequence Spread Spectrum) and its ability for interference. Based on it, the ZIF DSSS system design and index is brought forward, including the hardware implementation on MAX2820 and FPGA bandboard.In testing , the hardware board works with high-performance.Then the paper discusses baseband receiver algorithm.This algorithm is applied for carrrier and bit synchronization, AFC (Automatic Frequency Control) of MAX2820. The algorithm comprises of PN acquisition ,PN tracking, leftover carrier estimate and AFC algorithm. This technology makes great sense to short-distance wireless communication and TD-SCDMA.The last part of this paper gives the result of symbol error rate of the system correlate to the threshold in practical testing ,also the summary and the possible extensions and improvements.