Research On Saturating Jamming To Transparent Transponder Based On Time-frequency Atoms

Satellite communication plays a fateful role in modern wars, and it is a challenging problem to jam the communication satellite data links. Based on the fact that multiple access communication performance can be deteriorated seriously by intermodulation products, this thesis puts emphases on the saturating jamming to transparent transponder supporting FDMA satellite communication system.After analysis of satellite uplink, transponder architecture and nonlinear amplifier character of TWTA, this thesis mainly analysis and simulate about the jamming ability of time-frequency atom interference mode to transparent transponder. The author’s main work and contributions are as follows:1. The power range of interference that can make transparent transponder saturation effectively is analyzed. The formula for C/N at the output of transponder to single access system and multiple access system under saturation interference is derived.2. An FDMA nonlinear communication system includes transparent transponder with MATLAB7.0 is built up. Using semianalytic BER estimation method, the performance analysis of under different input back off is given. Two limits in nonlinear distortion deteriorating system performance is put forward.3. The interference mechanism of time-frequency atom interference mode that can make the transponder-saturated is emphasized. Through simulation, the optimal parameters for the time-frequency atom interference mode are found. And an comparison between the interfering capacity of time-frequency atom interference mode and that of the noise-modulating-frequency interference mode is then evaluated. The result demonstrates the advantages of time-frequency atom interference mode.