An Improved Method of Frequency Domain Bandwidth Synthesis

摘要

Frequency Domain Bandwidth Synthesis (FDBS) technique enables ultra-high range resolution profiling of radar targets by Linear Modulated Stepped Frequency (LMSF) signal. There are two types of FDBS methods suitable for LMSF signal. One compresses narrowband pulses before bandwidth synthesis, while the other modifies the wideband spectrum resulted from bandwidth synthesis. However, the former may generate range profiles with high grating lobes due to the fluctuation of the synthetic spectra, and the latter is sensitive to noise as a result of modifying the rapid fluctuation of the synthetic spectra. Therefore, this paper proposes an improved FDBS method which not only represses synthetic spectra's fluctuation but also owns excellent anti-noise ability. Meanwhile, the method eliminates the correlation between the spectral overlapping proportion of adjacent sub pulses and the performance of bandwidth synthesis, and finally outputs high quality range profiles. Simulation results are presented to verify the validity of the improved method.