The Study And Fabrication Of Broadband Dual-polarized Probe Array

In this paper, the broadband dual-polarized probe array antenna is designed, which includes the study of modulation scattering technique, the design of Broadband single-polarized printed dipole, the design of broadband dual-polarized printed dipole, the design of feeder system, the analysis and design of dual-polarized printed dipole array, the research of probe array and so on.In the near-field antenna measurement, the signal of probe is very weak; the use of modulation scattering technique can overcome this defect. And the probe array instead of a single probe mobile technology can significantly reduce measurement time. The near-field measurement system which uses modulation scattering technique should choose a suitable antenna as a probe. In this paper, printed dipole antenna is chose as probe.Printed dipole has the advantages of simple structure, easy production and easy to form array. This paper first simulates and optimizes the structure of single-polarized printed dipole, further broadening its bandwidth. On this basis, a dual-polarization printed dipole is designed, which could work in both linear polarization modes, primarily through the handling of the Balun feeder. In order to make it work in the greatest possible bandwidth, the structure of it is simulated and optimized. And the consistency and isolation of it must maintain good.The feed system of dual-polarized probe array antenna is a one-four Wilkinson power divider. The power divider uses the microstrip line structure. In the geometric shape of power divider, the first impedance transformation line uses the form of arc. The form of arc can reduce the discontinuous of power divider, improve the input VSWR, broaden the working band of power divider and reduce the impact of mutual coupling.Dual-polarized probe array is a linear array, which is consisting of four dual-polarized printed dipoles. In order to get more big isolation between the elements of array, the pitch of array is simulated and optimized, and the structure of array is adjusted. Big isolation can reduce the mutual coupling of array elements. It ensures the consistency and bandwidth of probe array.