Spectrum Sharing System Implementation And Testing The Physical Transmission Link

As an emerging spectrum sharing technology, Cognitive Radio technology canimprove the utilization of the spectrum resources to solve the problem of the shortage ofspectrum resources. Cognitive Radio can share the spectrum resources with authorizedusers and do not affect them for dynamic opportunistic accessing to spectrum forcommunication through detecting for idle spectrum in environment.The paper provides an effective physical transmission scheme for dynamicspectrum sharing demonstration system based on digital TV channels. According to theDySNet system requirements, the performance of the different transmission scheme isverified by computer simulation. A transmission link based on DSP+FPGA architectureand interface protocol programs is designed and the DSP code is completed. Finally,combined with other parts of the demonstration system, a large number of tests areimplemented.This paper focuses on the implementation of physical transmission link in dynamicspectrum sharing broadband wireless system network. Firstly, it discusses the floatingpoint and fixed-pointed data link simulation performance based on the demand and thetransmission scheme of the system. Then it completed interfaces debugging andprotocol designing between DSP and FPGA, DSP and DSP, DSP and MAC for dataprocessing and results reporting. And by analyzing the system requirements, it designedthe software threads of data process scheduling based on DSP/BIOS, each thread dealedwith the transmitted or received data and in response to the commands from upper layerwith basic hardware. At last, system testing and debugging is completed in698~806MHz, including the sensing function and services transmission and so on. All the testsshow that the physical transmission link can work and ensure for the normal operationof the system accurately and stably, and provide a fully realistic basis for theapplications of the spectrum resource sharing.