Dsss Communication System Interfere With The Performance Evaluation And Simulation

As a new communication mode, the spread spectrum communications are widely used in military communication, distance finding and precise position, because of its well multiaddress access, lowly capture probability, the excellent performance of anti-interference and secrecy. The spread spectrum communication's availably jamming becomes the key to get the electronic war's victory, so it is very important to research the effectiveness of jamming and interference referred to the direct sequence spread spectrum (DS-SS) communication system.Based on DS-SS technology, this Master Dissertation profoundly studies many kinds of different jamming signals, evaluates the effectiveness of them and makes simulation. The main work includes three parts: 1. The modeling and simulation of the DS-SS communication system. 2. The evaluation and simulation of high power single jamming's effectiveness. 3. The evaluation and simulation of low power distributed jamming's effectiveness .In the first part, the DS-SS communication system's operating principle and its performance are studied, PN sequence which is the most factor to the DS-SS communication system's performance is introduced and analyzed. In order to combine the study of the DS-SS communication system's availably jamming, the whole DS-SS communication system is modeled and simulated, including the modulation of the DS-SS signal, channel transmission, synchronal demodulation of signal and statistic of the Bit Error Rate (BER). Then this dissertation compares the theoretical analysis of the BER on white noise and its computer simulation results, testifies validity of the simulative model.In the second part, this dissertation mainly researches the effectiveness of general high power single jamming and interference. Based on classification of general jamming signal, generalizing them and analyzing their performance, the effectiveness of the pressing jamming and interference is deeply studied. The optimal jamming bandwidth of the wideband white noise and the optimal jamming frequency of the single sinusoidal signal are deduced by theoretical analysis and detailed derivation.