| 摘要 |
Microwave carrier frequency energy is switched from one beam to another to provide a switched scanning beam for the glide slope function for an instrument landing system. The beams comprise a plurality of upper beams of uniform angular width in elevation and having a uniform angular center-to-center beam spacing in elevation, together with a class of lower beams consisting of at least one beam with each beam of said lower beams having a reduced angular width in elevation and a reduced spacing beneath the center line of the next higher beam which is proportional to the reduced beam width, the peak energy radiated at the center line of each lower beam being inversely proportional to the peak energy radiated in each of said upper beams as a function of the respective beamwidths. |
