CELLULAR ANTENNAS FOR STRATOSPHERE COVERAGE OF MULTI-BAND ANNULAR EARTH PATTERN

摘要

Cellular antenna systems are provided for airship-type support at a position in the stratosphere. A single antenna system (20) may provide cellular communication for earth-based users located anywhere within a circle 400 miles in diameter (10). By use of array assemblies (21a) each providing 12 side-by-side beam positions per quadrant, with higher and lower elevation beams (32a', 36a') at each beam position, coverage can be provided for 96 cells arranged side-by-side in inner and outer annular bands (10). A turnstile-type antenna (26) provides coverage for a 97th central circular cell. By allocation of available groups of cellular frequencies in repetitive patterns around the outer annular band (1-6), with frequency reuse in offset positions around the inner annular band, 16 times frequency reuse is provided while maintaining acceptable co-channel interference levels. A total number of channels of the order of 5,800 channels is thus provided for AMPS band A or band B usage with a single antenna system.