The spread spectrum communication technology has been already widely used especially in the military filed because of its advantages such as high communication security, anti-interference capability, high utilization of spectrum and low interference to other communication systems etc. Direct sequence spread spectrum is one of the common methods to spread the spectrum and is used in satellite communication, location, secret communication and navigation etc. So it is meaningful to analyze the basic principle and characteristics of DSSS system.

In this paper, the research background is firstly given, then there is a detailed theoretical analysis on the principle and characteristics of the DSSS system. After a detailed discussion on DSSS system, the DSSS system is compared with another commonly used technology-FHSS. The advantages and disadvantages of DSSS compared with the frequency hopping system are summarized and the development of the technology in the future has been prospected.