Spectrum Sharing Spectrum Perception Communication System Links The Fpga Implementation Study

Spectrum resources shared wireless communication system is one of the “863”major projects, aiming at the establishment of a verification platform for cognitive radio.It is used to verify the key technology of the cognitive radio, and its’ innovation point isthe integration of multiple wireless communication systems based on cognitive radio.Among them, the design and FPGA implementation of the baseband in the sense link ofthe system are the main contents of this dissertation.In accordance with the requirement of the spectrum sensing of the system, thisdissertation designs the general program of sprectrum sensing, including the sensingprocess, the signal modulate, the sensing algorithms and the sensing protocol.The design goal of the spretrum sensing of the system is to improve the probalityof signal detection and minimize the detection time as much as possible at the lowprobality of the false alarm. In order to achive this goal, considering the constraints ofthe hardware circuit of the system, this dissertation proposes a fast AGC adjustmentalgorithm suitable for the spectrum sensing link of the system by analyzing theperformance of different AGC adjustment progam.This dissertation designs the interface of the spectrum sensing link of the systembased on the hardware platform of the system. It includes the interface of ADC, theinterface between the RF and the baseband, the interface between the FPGA and theDSP.In accordance with the demand of the spectrum sensing of the system, thisdissertation designs the digital pre-processing program suitable for the spectrum sensinglink by analyzing the impact of the different signal pre-processing programs on theperfomace of the spectrum sensing.By analyzing the impact of adjacent channel interference (ACI) on the performaceof the spectrum sensing, this dissertation designs a simple algorithm of ACI suppressionwhich is easy to implement. And this algorithm solves the problem of deteriton of thespectrum sensing caused by the ACI.This dissertation completes the FPGA implementation of all above of the design on the system hardware platform, and verifies the feasibility and stability by timingsimulation and online testing.Finally, this dissertation verifies the normal operation of the spectrum sensing linkin the system by system-level test.