Sound Localization System Hardware And Software Design Based On FPGA

Source localization based on microphone array is an important application of array signal processing,which is widely used in military and civil fields such as individual combats,sniper azimuth determinations,video conferences,intelligent robots and so on.In view of the current source localization systems are mostly based on PC platform to complete data procession and determination of sound source location.It has the disadvantages of high price,complex operation,high power consumption and is not easy to carry.Therefore,this paper proposes a microphone array sound localization system ultilizing FPGA as the data processing platform,which makes it a small sized,portable,low power,low price system.It's of great value in the field of video conferencing,detection and military operations.In this paper,the source localization system is studied in three parts: theoretical research,software and hardware design and positioning experiment.Firstly,this paper compares and studies three kinds of positioning algorithms,such as beamforming,high resolution spectrum estimation and arrival time difference.Then conducted theoretical derivation of the three microphone linear model and the six microphone space model also the analyzed the cause of positioning error.MATLAB is used to simulate and compare TDOA algorithm and MUSIC algorithm.It is concluded that TDOA algorithm has the characteristics of small computation and good real-time performance,which is suitable for FPGA positioning system.Then,according to the system performance requirements,completed the source localization system hardware and software design based on FPGA.The hardware design includes signal conditioning circuit,power supply circuit,AD sampling circuit,SD memory circuit design,realizing the synchronous acquisition,storage and the analysis of eight signals,which makes it portable,low power consumption characteristics.The software design includes two parts: hardware circuit control and positioning algorithm,which is improved by using the module multiplexing,reducing the number of data bits,enabling control,flowing wate r structure and so on.Based on the hardware foundation,the program was optimized by using module multiplexing,reducing the number of data bits,enabling control and pipelining.All the modules are simulated and verified by Modelsim.Which provides the system logic resource consumption and positioning program simulation time consuming.Finally,this paper carried out a series of performance tests and positioning experiments on the sound localization system.The results show that the system design is reasonable,the accuracy meets the requirementsd and the sound source positioning effect is good.In view of the errors in the experiment process,this paper gives the system error analysis,and put forward the corresponding improvement program,which provides the idea for the follow-up study.Finally,this paper implements the acquisition,storage,analysis and location of sound source information on FPGA.