Design And FPGA Implementation Of 16QAM Based On Softerware Radio

In this thesis, 16QAM was accomplished on FPGA by combining the high spectrum efficient digital QAM technology and software radio,which has a great practical significance in today's increasingly scarce spectrum resources circumstances.Sampling theory and multi-rate signal processing technology , the basis of software radio were deduced and analyzed; Digital Down conversion technology, the core principle of software radio, and its realization structure were studied., This paper also analyzed the realization structures and properties of effective digital filter CIC, half-band filter, etc. Top-Down thinking method was used in the 16QAM modulation and demodulation system design.; Altera's Integrated Quartus II was used as EDA design environment. Debugging of the system used the algorithm simulation and in-system experimental methods.Firstly, this papers gave system-level simulation for 16QAM, and simulated the feasibility of the modules, then, provided the design of the square 16QAM modulation-demodulation overall framework; The modulation system including clock-module, string conversion module, constellation module, 8-times interpolation module, LFP module, as well as the AD9857-FPGA interface module was accomplished; On the other hand, band-pass sample module, 16-times Decimation CIC filter module and square-raised roll cosine filter in the demodulator were completed. Finally, the IF 16-QAM Time-Domain modulated signal was measured and the spectrum was analyzed; Consuming only 200KHz bandwidth,this system realized 512Kbp data rate. This thesis also did some research on the EPLL and its realization structure and analyzed its performance.