Theoretical Study on Measurement Accuracy of Rotating Element Electric Field Vector (REV) Method

摘要

The rotating element electric field vector (REV) method is an extremely effective measurement technique for calibration of a phased array. However, if there is any error in the excitation amplitude and phase of each element antenna, the measurements will contain an error. In this paper, the relationship between the error of the excitation amplitude and phase of each element and the measurement error of the REV method is obtained by means of probabilistic analysis theory. In the derivation of the theoretical equation, we study the error in the combined power of the array antenna (to be called the array combined power) when the excitation phase of the element is varied in accordance with the measurement principle of the REV method. Then, the error from the ideal condition without any error in the excitation amplitude and phase is expressed in terms of probability density profile. Next, the relationship between the error in the array combined power and the measurement error of the REV method is given by an approximate formula. As a result, it is clarified that the error of the excitation amplitude and phase of each element and the measurement error of the REV method can be related by a simple theoretical equation. The effectiveness of the derived theoretical formula is verified experimentally, indicating that the measurement accuracy of the REV method is amenable to analysis.