Non-Image Glideslope Investigation.
Final rept. 16 May 74-29 Feb 76,
TEXAS INSTRUMENTS INC DALLAS
Pagination or Media Count:
The analysis and design of a broadside glideslope antenna array and its shielded loop elements are presented. This non-image array is intended to replace the glideslope image array in regions where the latter does not perform well, such as in unlevel terrain or over tidal water. The synthesis of the array is presented with an analysis of its required height. The tower design and the design of a corner reflector behind the loops are given. The major effort was the design of the shielded loop, a single-turn loop of stripline construction. Its impedance is matched with a series stub and a broadbanding circuit integral in the stripline feed. An integral monitor design is also described. The sensitivity of the loop impedance to rain and ice is investigated, as well as the performance of various radome approaches. An integral radome and a conventional type are discussed. Finally, a three-element array with a small distribution network is described and its performance presented. Full-sized distribution and monitor networks are discussed. The feasibility of using the loop element in existing image arrays is demonstrated, and a detailed design of a coaxial construction with a single-rod reflector is given.
- Air Navigation and Guidance