Desigh of a time delayed receiver local oscillator in stepped-frequency radar

Stepped-frequency radar is a kind of high range resolution radar. Under high pulse repetition frequency (HPRF) mode, stepped-frequency radar has specific advantages such as clutter suppression and unambiguous velocity estimation. However, there is a paradox between radar´s detecting range and processing power under HPRF mode. To solve this issue, a time delayed RLO should be adopted to get a dynamic range window. The paper presents a dual DDS design method. Based on the dual DDS design, a theoretical analysis on the range shift caused by the RLO delay is proposed; meanwhile, a phase correction solution is also propounded. Experimental results have proved the effectiveness of the solution.