Research On The Transmission Performance Of The Satellite Mobile Communication System Compitable With The WCDMA System

With the advances of the society and the development of the technology, thethird generation mobile communication technology has been widely used in manyareas. The use of the terrestrial network can provide high bandwidth and low-costcoverage for the urban areas that have high density population, but there are stillsome areas that can not be covered by the terrestrial networks such as remote areasor when you are at sea and there are blind spots of the communication. Satellitenetwork has broad coverage, and its performances will almost not be affected bythe events that happened on the ground. It is the advantage of the satellite network,but there is also disadvantage of the satellite network, because it mainly rely on theline of sight communications. In order to achieve the goal of seamless coverage,we should consider the integration of the terrestrial network and the satellitenetwork, which is the inevitable trend of the development of thetelecommunications network. Therefore, it is of great significance to design asatellite mobile communication system which can be compatible with the WCDMAsystem.First, the paper introduces the concept and the framework of theintegrated/hybrid network which is defined as the next generation networks by theInternational Telecommunication Union. The two networks use differentcommunication system to provide the most effective service for mobile users in anew way.Then, each process and the performance of the WCDMA system is introducedin the paper. The paper simulate the performance of the bit error rate of theWCDMA system both in the Gaussian channel and the Rayleigh channel when it isin different signal noise rate by the program compiled with the MATLAB. And theresults of the two cases are contrasted.Finally, the paper introduces some knowledge on the satellite communicationsystem and simulates the performance of bit error rate of the WCDMA systemunder the satellite channel model of two-state Markov link when it is in the urbanand in the suburban, the results being contrasted with the data of the previouschapter. And it comes to a conclusion that the transmission performance of thesatellite channel depends on the channel bandwidth, the bit rate, the spreadingfactor and other factors. So a method is proposed to enhance the transmissionperformance by improving the spreading section, which makes that the performance of bit error rate of the WCDMA system in the satellite channel isimproved by adjusting the spreading factor in the end.