Research And FPGA Implementation Of Ultra-wideband Imaging Algorithm

Ultra-wideband technology is a new type of radio transmission technology. It has not sensitive to the channel fading, the transmitted signal power spectral density is low, low interdiction capacity, low system complexity, can provide the advantages of a few centimeters of the positioning accuracy.Ultra-wideband signals can identify moving objects hidden objects or wall, to achieve a combination of three functions of radar, positioning, communication, suitable for military tactical communications. In addition, it can also be used for rescue and relief missions after the fires and earthquakes, can be quickly and accurately search and rescue of victims covered by the smoke or ruins. Has a very high range resolution, ultra-wideband signal low-frequency component to ensure good penetration characteristics and a greater role distance.To achieve the good performance of the signal receiver, in addition to the design of the system have a good hardware support, the signal processing is also a very important aspect. Therefore, this thesis ultra-wideband signal receiver signal processing in-depth and meticulous research, and FPGA development board part of the receiver, give full play to the configuration flexibility of FPGA programming, strong advantages in resources, reduce the number of devices to meet the real-time system design, high integration requirements.Firstly, according to the needs of the application background of hardware platforms and software architecture outline design analysis. And block diagram form, with the structure described in detail.Secondly, on the basis of the outline design, detailed design of the median filter module. Firstly, the MATLAB simulation model to verify the feasibility of the median filter. Use the dsp builder development tool for graphical design and then integrated in MATLAB Simulink environment, give full play to the resource advantages of the FPGA to take parallel processing, real-time requirements. Third, in the summary of the design on the basis of the fast Fourier transform of the detailed design. Butterfly transformation model is derived, and then use Quartus Ⅱ integrated development environment the VHDL development language design. Butterfly design, address, independent dual-port memory design, the design of the complex multiplier and twiddle factor MATLAB software generation.Fourth, on the basis of the outline design, image generation module detailed design. First there are no obstructions case analysis of the positioning model of the three-round with oval positioning model and gives the solving methods. And then there are obstacles in the case of the original model to be amended. Finally, on the basis of this theory, the image generating method.Fifth, the detailed design of the overall control module. In order to solve the resource repetitive utilization of resources on the part of the sheet between each functional module, by the end of each module is detected signal to control the working state of each module, and the allocation of repetitive use. Finally, in Modelsim and Simulink simulation module, and crawl through the line Quartus Ⅱ integrated logic analyzer (Signal Tap Ⅱ Logic Analyzer) FPGA real-time data, to give the final imaging results.In summary, in the MATLAB simulation and experiments based on the ultra-wideband signal receiver part of the function module, the echo signal filtering, analysis and processing, and gives the results of simulation and debugging for real-time, the accuracy of the target position and being a good foundation.