The Broadband Satellite Communication System’s ACM Application Research On Based On The DVB-S2 Standards

With the rapid development of terrestrial communication network, life becomed more and more convenient, however, there were no enough communication resources in some remote areas because of the restrictions of optical fiber in our country. People needed more broadband multimedia services, therefore it was important to establish satellite communication system. The information of user with different areas to satellite which was transmitted in the sunny day and rainfall condition could get different signal attenuation in our country, so using adaptive coded modulation technology could make full use of limited satellite communication transmission bandwidth and decrease information’s ber.DVB-S standard was used in the world’s most satellite digital broadcasting system, but there were some problems need to be improved urgently, such as transmission performance, modulation coding method and different code rates. DVB-S2 standard was based on DVB-S standard, and it had new channel coding mode, high order modulation technology, ACM(adaptive coded modulation) technology.This paper researched ACM application technology on the broadband satellite communication systems based on the DVB-S2 standards, and the content covered the collaborative simulation of the link software and the network software, the link simulation of broadband satellite communication system, the network simulation of broadband satellite communication system, ACM technology application and the rainfall attenuation for signal, and so forth, then the following research results were obtained:1. This paper simulates the DVB-S2 standard using the combination of the link software and the network software. In the link stage, MATLAB software simulated the DVB-S2 standard in detail. In the network stage, DVB-S2 standard and broadband satellite communication systems were simulated, and then ACM technology was used in this simulation process. In simulation process, OPNET could use the data simulated by MATLAB. Through the simulation process and simulation results we can see that the combinalation of the two softwares could make the simulation of DVB-S2 well. 2. In the roadband satellite communication systems link simulation stage of broadband satellite communication system, the link simulation software MATLAB was used to complete DVB-S2 standard simulation, and then, several modulation coding methods which could be used in next network simulation stage was given a key research. Through the simulation results we can see that MATLAB software had very good support for DVB-S2 standards.3. The montecarlo method was used to simulate signal-to-noise ratio-ber parameters. In the link simulation stage of broadband satellite communication system, it was necessary to simulate different modulation coding ways. If only one communication process, it would not be able to finish the needed transmission information size in one modulation coding way. In order to achieve needed ber accuracy, one modulation coding way needed to be simulated for a few times according to the simulation requirements. This was the process using montecarlo method, and through the application of this method, the bit error rate in one modulation coding way could be more precise.4. In the satellite communication network simulation process, ACM technology would call the modulation curve generated in the pervious stage and change the information sent rate properly, and on the basis of that, the specific broadband satellite communication system was simulated. The simulation results showed that, ACM technology could indeed make full use of limited bandwidth to ensure communication system link chear on condition that the error rate didn’t increase.5. For the broadband satellite communication system could work under different weather conditions, in the end of this article, in the study of different scene parameters’s broadband satellite communication system, the rainfall attenuation for signal transmission influence was considered, then the link allowance under the sunny day and the link hige results of using ACM under rainy day were given in the end of this article. The simulation results showed that the application of ACM technology could actually make a communication link less likely to break,...