The Design And Implementation Of A VSAT Communication System Based On DSSS

A design and implementation of a VSAT(Very Small Aperture Terminals) communication system based on DSSS (Direct Sequence Spread Spectrum) has been presented in this paper. It is one important part of the project 'design and implementation of a real-time watch and control system based on VSAT'. This system is used for transform data from VSAT station to high-speed mobile terminal. Unlike traditional Narrow-band communication system, this one should be much more robust and secure.The DSSS system has inherent capability to counteract narrow-band interference. Meanwhile, if the spread code can be used effectively, we can achieve a pretty good security level. Spreading a fixed amount of transmitter power over a wide bandwidth lowers the power spectral density. This means the DSSS system is a low-detectable system compared with traditional narrow-band communication systems. Since it is necessary for the control link to be robust, secure, low-detectable and insensitive to hostile interference, the DSSS techniques have been employed in this design.The implementation of the system can't lack devices. After designing of the framework of physical layer of this system,the following for us is to think of implementation of hardware,involing of which chips we select to finish the functional modules,how to use and how connect of each chip.According to the charcacter of physical layer of this system,The DSP,FPGA and special chips have been selected to implement the initial design. What's more,The final printed circuit board has been designed.The functional test is necessay in the developing of system. Due to the character of system and the circuit,a serias of test has been made in order to debug and optimize the functional modules.The architecture for this paper is organized logically well in a manner starting from theory to system and further pushing system into...