Abstract: For achieving fast imaging for ultra-wideband step frequency continuous wave radar in near-field, and improving the imaging resolution, a imaging algorithm is proposed for ultrawideband step frequency continuous wave radar. This imaging algorithm derives the electromagnetic wave equation according to the transmission and propagation characteristics of step frequency continuous-wave signal, which is used angular spectrum analysis method. The algorithm eliminates the need of matched filtering process, and is accurate for imaging. Three-dimensional electromagnetic simulation software of HFSS is applied for modeling and simulation. It collects data in the simulation results for verifying the feasibility of imaging algorithm. The results show that the target energy is concentrated in imaging figure, and has high resolution. Theoretical resolution of imaging is 0.15 m, and actual resolution obtained is 0.2m for the frequency range of 0.5~1.5 GHz and 1 GHz bandwidth of the transmitted signal.

Key words: Ultra Wide Band（UWB）, stepped frequency, radar, near field, imaging algorithm

摘要： 为了实现超宽带步进变频连续波雷达近场区高分辨率快速成像，提高成像的分辨率，根据步进变频连续波信号发射与传播的特点，采用角谱分析方法，通过对电磁波波动方程进行推导，提出一种适用于超宽带步进变频连续波雷达的成像算法，该算法省去了匹配滤波过程，成像准确。采用HFSS三维电磁场仿真软件进行建模仿真，在仿真结果中采集数据验证成像算法的可行性。结果表明，成像图像中目标能量集中，分辨率高，对于采用的频率范围0.5~1.5 GHz，带宽为1 GHz的发射信号，理论分辨率为0.15 m，实际得到的分辨率约为0.2 m。

关键词: 超宽带, 步进变频, 雷达, 近场, 成像算法