Microwave Landing System, Elevation Units Feed System Design

This paper primary introduces the design of the antenna and its feeding circuit network which is used in the elevation plane of the MLS. The frequency of the operation is C band.It is composed of that: the design of the element of the antenna, the design of the array of the antenna, error analysis, cross coupling analysis and the design and test of the feeding circuit network.The symmetrical dipole fed by TEM transmission line (stripline) is adopted for the element of phased array antenna, which is apt at realizing the integral design of antenna and its feeding circuit. The vertical polarization is used to avoid the blindspot.The aperture distribution of the linear array is Taylor distribution. Many factors are considered to determine the prime space ultimately, which makes the antenna get the highest gain and lowest side lobe and reduce the affect of the cross coupling.The type of the power divider is Wilkinson power divider, and the stripline is filled with foam in feeding circuit network, which is completed by calculation and simulation by some software, such as HFSS and Designer.In addition, the error analysis is discussed on the performance of the antenna array, and the MOM is used to calculate the affect of the cross coupling on the current distribution and the pattern diagram.The design has got the requirements showed by the testing results, and successfully applied in practical project.