DSP Implementation Framework Of SAR Algorithm That Based On Multicore Multithread

Synthetic Aperture Radar(SAR)is an important branch of radar,and has been widely used in various high-speed motion platforms.China attaches great importance to the missile borne SAR imaging.For the missile borne platform,the high squint SAR imaging algorithm is essential.Because of the complexity of the imaging algorithm and the high resolution of the imaging resolution,the requirement of the engineering real-time performance is very strict.Based on the above background,this thesis designs the DSP architecture in the signal processing system based on the high squint algorithm of high speed platform.Improvements are made in the following aspects: the signal processing system is more stable,the imaging effect is the best and the real-time performance meets the requirements:1.The missile borne platform usually in a high squint working state at the terminal guidance stage.Aiming at this characteristic,A high squint high resolution frequency domain imaging algorithm under high speed motion platform is proposed.This algorithm is an improved nonlinear frequency modulation scaling algorithm.By constructing a high frequency phase filtering factor in frequency domain,the azimuth variable term is eliminated and the azimuth focusing effect is improved.2.In order to achieve high real-time performance of missile borne platform,a multi-threaded and multi-core DSP programming method is designed.It breaks through the key technologies of multi-threaded multi-core DSP memory management,thread scheduling,and dynamic memory development,so that the switching time between tasks is shorter;The inter kernel multi-core synchronization method is designed for Notify synchronization based on SYS/BIOS operating system,and inter kernel communication is carried out with the highest real-time inter nuclear interruption.Based on real-time consideration,multi card is used to deal with the inter kernel.The structure of the board is designed to be a data flow structure.3.For the complex environment of missile borne,we need to ensure that the DSP architecture must have higher stability.The system architecture of DSP on the signal processing board is designed,including the switching and synchronization between tasks;the data flow pattern on the board is designed,including the flow mode of data flow between the two DSP chips on the board and the data flow between the boards.The data transfer and synchronization mechanism between different tasks,multi core synchronization,DSP chip and the data flow between signal processing boards are the difficulties in the design of DSP architecture.A large number of multi thread and multi core DSP architecture is used to carry out a large number of simulation experiments,and then applied to airborne flight experiments.Finally,the real-time and stability of the architecture can be determined to meet the imaging requirements of the high-speed motion platform.