Abstract
Coherence is an important quality of radar signal. DDS + PLL Hybrid scheme becomes one of the most important and dynamic research in signal generating. In this paper, a novel DDS + PLL Hybrid scheme with the sweeping voltage circuitry is proposed to solve the problems in the classical scheme, such as poor stability, large design difficulty and long acquisition time. Meanwhile, pre-distortion is also proposed to compensate the static phase error, which improves the coherence and pulse compression performance. The measurements of the test system indicate the proposed scheme reduces the acquisition time and improves the coherence effectively.