Implementation Of ISAR Imaging Algorithm Of Ship Target Based On TS201Hardware Platform

Coastal Inverse Synthetic Aperture Radar (ISAR) is a new general coastal defensesystem. The main signal processing techniques include detection and imaging of shiptargets. This paper focuses on preprocessing of echo data, ie, Digital Down Conversion(DDC) of two-channel signals, and implementation of ISAR imaging algorithm basedon TS201chip. Details of the DDC process and programming with software arepresented. At last, this paper analysis ISAR imaging algorithm, and finish the work ofreal project.Detection channel is to detect and track targets, providing prior information forimaging channel. It facilitates imaging channel to record echo data of imaging channel,removing redundant data and reducing the amount of computation. In this way, it’s ableto realize the purpose of real-time tracking and imaging of ship target.DDC technology can effectively reduce the data rate, meanwhile it is able togenerate two-channel orthogonal baseband signals, which is necessary for detection andimaging. This paper analyzes the CIC filter’s characteristics and presents an equivalentstructure of cascaded CIC filter, improving DDC architecture to facilitate the rapidcompletion of DSP operations. Detection and imaging channels require differentdown-conversion parameters, as a result, different implementation steps are presented.Then, a multi-processor system is established to enhance the system’s processingcapability. Developing DDC with DSP leads to convenient debugging and shortdevelopment cycle. At last, we verify the accuracy of program with simulation, and theorthogonality of I/Q dual output signals with actual sinusoidal signal.At the last chapter, this paper elaborates ISAR imaging algorithm and severalcommon motion compensation methods, including range alignment and phasecompensation. We analyze the characteristics of each method and its influence onimaging result. Then we establish a model of ship echo model. Simulation datademonstrates the imaging results, both with matlab and DSP. Finally, imaging results ofseveral sets of real-measured data are presented.