关键词: 相控阵雷达, 移相器, 电荷泵锁相环, 数字移相, 数控电流源, 集成电路

Abstract: Phase shifter is the core device of phased array radar (PAR). With the gradual increase of the working frequency, the insertion loss and phase control error of the traditional phase shifter get worsen seriously, resulting in additional power consumption and poor beam performance. In this paper, a high-precision digital phase shifting method based on CP-PLL is investigated. Based on the analysis of CP-PLL mathematical model and phase-shifting mechanism, the method of numerical control current source is proposed to realize the accurate control of the output signal phase, the circuit model is established to carry out simulation analysis, and the experimental circuit module is designed. The effectiveness and accuracy of the method are verified by the comparison of simulation and measurement. The results show that the phase-shifting step is better than 1°, and the accuracy is better than 10% of the phase-shifting value. The CP-PLL can be used in PAR as a local oscillator or as a direct transmitter signal. It has the characteristics of high precision, low power consumption and easy integration, which can replace the phase shifter and effectively improve the performance of PAR.

Key words: phased array radar, phase shifter, charge pump phase-locked loop, digital phase shift, numerical controlled current source, integrated circuit