相关干涉仪测向具有算法简单、测量精度高、抗干扰能力强等优点，是主流的测向体制之一。均匀圆阵能够实现二维测向，并且具有结构紧凑、测向精度均匀等优点。结合两者的优点，研究了均匀圆阵相关干涉仪测向算法。为克服电域鉴相器工作频率低、带宽窄、易受电磁干扰影响的缺点，提出了一种微波光子鉴相器。利用双平行马赫曾德尔调制器（DPMZM）建立一个光干涉仪结构，将两路微波信号的相位差映射为输出信号的光功率。通过调整DPMZM直流偏置电压，使得DPMZM中的相位偏置分别为0°和180°，并分别测量两种情形下的光功率。利用光功率的比值建立相位差映射函数，提高了功率测量的分辨率和相位差测量的精度。最后，通过仿真验证了所提方案的有效性，所设计的微波光子鉴相器能够实现0°~360°的相位鉴定，测量误差为±1°，对应测向算法的测向误差为1.0082°。

As one of the mainstream direction finding schemes, correlative interferometer has many extraordinary advantages, such as low complexity computation, high accuracy, strong anti-interference etc. Besides, the uniform circular array can measure the azimuth angle and elevation angle simultaneously, and has the advantages of uniform direction finding accuracy and compact structure. Motivated by the above, this paper investigates the correlative interferometer direction finding using a uniform circular array. Since traditional electrical phase detectors are faced with some bottlenecks, such as bandwidth limitation, low frequency, electromagnetic interference etc., a photonic phase detector scheme has been presented to measure the phase difference. A dual-parallel Mach–Zehnder modulator (DPMZM) is adopted to construct an optical parallel interference structure which can estimate the phase differences by optical power measurement. The phase shift in DPMZM can be set to 0° and 180° by adjusting the DC bias. Then, the power of the output optical signal can be measured in both two cases. Besides, a Phase difference mapping function based on the ratio of optical power measurements has been proposed to improve the resolution of the power measurement and the estimation accuracy of the phase difference. Finally, the availability of the proposed scheme is investigated via experiments which shows that measurement error of phase difference is less than ±1° from 0° to 360° and the angle-of-arrival estimation error is less than 1.0082°.

中国博士后科学基金c；国家自然科学基金(61901502)