Performance Research and Simulation on DSSS System with Short Spreading Code against Single Frequency

In connection with increasingly extensive application of wireless spread spectrum system and problems in interference aggravated continuously, this paper proceeds thorough research on the performance of direct sequence spread spectrum (DSSS) system with short spreading codes against interference. Particularly, in view of effects to system performance resulted from single frequency interference, based on the brief account of the analysis method obtained from the traditional stand Gaussian approximation (SGA) hypothesis and the latest research results at home and abroad, the effects are further theoretical analyzed and simulated with computer. The results indicate that the analysis obtained from SGA was not suitable for the DSSS system with short spreading code. The interference component of the symbol decision variable in the DSSS system with short spreading code takes on a constant level or a monochromatic fluctuation due to single frequency interference with different frequency offset. When the frequency offset satisfies different conditions, the interference component is whether periodic or not.