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摘要: 微型合成孔径雷达(MiniSAR)有效突破了时间与空间的限制,具备轻量化、低功耗、高灵活度等优势,能够满足感兴趣区域(ROI)的高分辨成像需求。然而,MiniSAR成像信号处理依然面临若干技术难题,例如复杂航迹条件下对地面目标的高分辨成像,非合作动目标的重聚焦,数据处理的效率与实时性等。据此,该文提出了一系列成像信号处理技术及其对应的现场可编辑门阵列(FPGA)硬件设计架构,从而实现了MiniSAR高分辨率成像与实时性处理。最后,基于多组聚束/条带式MiniSAR试验结果,验证了该文方法的有效性和可靠性。Abstract: Miniature Synthetic Aperture Radar (MiniSAR) has been making breakthroughs to effectively overcome the limitations of time and space, and has exhibited superiority with respect to light weight and low-power consumption as well as high flexibility to achieve high-resolution imaging for the Region Of Interest (ROI). However, imaging signal processing for MiniSAR systems still face several technical challenges such as high-resolution imaging of ground targets under complicated trajectories, refocusing of non-cooperative moving targets, and efficient and real-time processing of echo data. In this paper, a series of imaging signal processing and associated hardware designs using Field-Programmable Gate Array (FPGA) architecture have been proposed to realize MiniSAR ultra-high-resolution imaging and real-time processing. Additionally, experimental results utilizing considerable spotlight and stripmap MiniSAR data have been presented to demonstrate the effectiveness and reliability of the proposed technology.
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表 1 资源利用率
Table 1. Resource utilization
资源 已用资源 可用资源 利用率(%) Slice Registers 355480 866400 41 Slice LUTs 273549 433200 63 Block RAM/FIFO 501 1470 34 DSP48E1s 1204 3600 33 表 2 主要的系统参数
Table 2. Main system parameters
系统参数 数值 带宽(GHz) 1.8 载频(GHz) 9.7 飞行速度(m/s) 5 脉冲宽度(ms) 4 数据采样率(MHz) 50 脉冲重复频率(Hz) 250 -
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