Aircraft Antenna Analysis and Microwave Landing System (MLS) Applications.

摘要

The purpose of this investigation was to develop analytical methods for predicting the radiation characteristics of antennas on aircraft. Diffraction techniques in conjunction with other classical electromagnetic methods were used to take into account contributions from various structural features of an airframe (tail, nose, wings, and main fuselage). Computed values were compared with measured data of antennas on scaled model aircraft such as 1/35 scale space shuttle, 1/11 scale Boeing 737, and 1/25 scale KC-135. A very good agreement between theory and experiment was indicated. With the availability and versatility of the analytical techniques, computations were made for antennas on full scale aircraft such as the Boeing 737, Boeing 747, and KC-135. The frequency of operation of the antennas on the full scale models was 5.1 GHz which is within the proposed band for the MLS. Of the antennas, locations, and aircraft examined in this investigation, a circumferential aperture, which is vertically polarized in the elevation plane, mounted below the nose (station 169) or above the cockpit (station 306) of a Boeing 747 provides the most attractive coverage for MLS application. A vertical monopole also demonstrates good coverage, but it is not as attractive as that of the circumferential aperture. (Author)