Research Of Shortwave SSB Modulation And Demodulation System Based On FPGA

HF communication has the most remote history among wireless communicat-ions, which has been an important means of medium range and remote commun-ications in the world.It is widely used in government,military,diplomacy,weather, business and other fields.The characteristics of short-wave communication as sim-ple device,flexible,low-cost,long transmission distance and survivability performan-ce make the short-wave communication,whether for civilian or military occupying an extremely important position.This thesis focuses on the principle of shortwave single-sideband modulation and demodulation techniques,and the system design and implementation based on FPGA.As the most popular modulation techniques to achieve short-wave radio si-ngle sideband modulation technique can effectively improve the communication quality,greatly reduce the transmission power,save frequency resources,but also ca-n reduce the corresponding interference between radio waves.First,the single-sideband modulation and demodulation system theory was bri-efly introduced,including several basic methods on the realization of single sideb-and modulation and demodulation technology which are analyzed and compared noted and highlighted the completion of short-wave single-sideband modem tech-nology design of,and then systematically introduces the ideas to achieve single s-ideband modulation and demodulation theories based on software radio technolog-y,including interpolation,DDS technology,and focused on not only the performance of three interpolation filters achieving interpolation ways of realization,but also t-he design of its FPGA implementationmethods,at the same time in the Xilinx Inc. ISE8.2 environment,using hardware description languageVerilog HDL to verify the design accuracy of each part;and using Modelsim simulation,combine all the mo-dules according to the design of the whole system.Theoretical analysis and com-parison of simulation results show that the system design is correct, and system performance is good.The short-wave single-sideband modulation and demodulation systems based on FPGA designed by this thesis is a research based on hardware realization in the laboratory stage.Results can serve as the basis for follow-up applied research and is of certain reference value for various kinds of communication systems us-ing the idea of software radio.