Analysis & Simulation For Wideband Multimedia Satellite Communications Channels With Turbo-codes

In this paper, the big Doppler effect specific to the wideband LEO multimedia satellite communications channels are mainly dealt with and a computer simulation model which can accurately describes the channel characteristics is established. Based on the above study, the digital communication system model is simulated and encoded as well as decoded by the turbo code, thus giving an analysis of the application of Turbo-code in the satellite communications.Through simulation, the following conclusion can be made:1. The bigger the signal-to-noise ratio of the channel is, the better the error correcting performance of the Turbo-codes is.2. With the increasing of iterations, the channel performance is better. However, when the iterations reach a certain level, the channel performance cannot be greatly improved. Furthermore, the increasing of iterations can increase the decoding time delay.3. In the case of low signal-to noise ratio, the increasing of iterations cannot make a greater improvement of the whole performance, which is less prominent than that of the big signal-to noise ratio.4. The channel of AWGN is distinctly different from the Rice channel. In discussing the performance of the Turbo in the LEO multimedia wideband satellite communications, the simulation of the true channel should be carried out as possible as it can be. In this way, the more accurate results can be made.