Research Of GPS Signal Simulation And Jamming Technology

Spread spectrum communication technology because it can hidden signal in noise and interference, with a strong ability to secure communications, has been using far and wide.As one of satellite communication systems with simple equipment and high precision in the world, the U.S. Global Position System (GPS) has been applied in the field of economic development and scientific experiments besides the military using. But the GPS only be designed as a navigation aid tools,its own unique characteristics make it very easy to interference.Therefore,study the interference of it become more and more important.Starting from the spread spectrum communication technology, the paper further discussion the content of the common direct sequence spread spectrum based on a brief introduction of its characteristics and work ways.It contains the composition ,working principle and modulation of the DS system,the signal composition analysis and its spectral characteristics.Also describe the generation and characteristics of the pseudo-random sequence (Gold sequence) ,which sequence is one of the most thriving methods of GPS.And then introduct the composition of the GPS system,GPS signal structure and common signal modulation methods, analysis the variety reasons why the GPS vulnerable to interference by jamming and the object which is easy to interference, citing the existing interference ways and GPS interference channels. The key study of the paper is to use the matlab as a simulation platform to bring out the process of GPS signal spread spectrum modulation send and receiver despreading demodulation, and how to add noise and jamming in the transmission.By changing the interference ways and JSR ratio in transmission channel, calculated the system BER in different jamming, finally analysis the interference effect of GPS on different jamming ways through the curve.