球面近场测试高阶探头补偿算法及其在超宽带探头上的应用

为了提高基于超宽带探头的球面近场天线测试系统精度，相应的探头补偿算法需要考虑超宽带探头的高阶方位模式. 文中采用文献3]中基于球面波的迭代法方案实现了高效高精度的高阶探头补偿算法，并将其应用到一种工作在2～18 GHz的超宽带双脊喇叭探头中. 同时以偶极子阵列为例，研究了本文算法相较于传统低阶算法的精度优势，测试了该算法在多种条件下的收敛性. 结果显示:在相同条件下，高频端比低频端的高阶补偿效应更加明显；当待测天线完全落在该探头的主瓣6 dB宽度区域内时，算法均可以在几次（小于10）迭代后达到理想的精度. 因此，本文算法可以有效地提高基于超宽带探头的球面近场测试系统的精度，并且具有较高的单机计算效率.

High-order probe compensation algorithm for ultra-wide-band probe in spherical near-field measurement

In order to increase the precision of spherical near-field antenna measurement systems based on wide-band probes, probe compensation algorithms supporting high-order azimuth mode (HOPC) are needed to process the near-field measurement data. In this study, an HOPC algorithm is realized based on the iterative strategy in the reference 3] for solving the spherical-mode transmission equation with high-order probes. This algorithm is applied to a dual-ridged wide-band horn probe that works in the frequency range of 2–18 GHz. Using dipoles array antennas as examples, the higher precision of the high-order algorithm is illustrated compared with that of the low-order algorithm. The convergence of the algorithm under different conditions is also systematically tested. These results indicate, firstly, the higher-order effects are more remarkable for higher frequency and secondly, when the antenna under test can totally be covered by the 6 dB domain of the main lobe, the iterative process can converge to satisfactory precision within several iterations. Therefore, the algorithm in this paper for HOPC can increase the precision of the spherical near-field system while still preserves high computational efficiency.