Adjustable spiral antenna for portable use

摘要

A spiral, helical antenna is configured to produce a generally circular polarized radiation pattern covering a range of frequencies, over a ground plane. The antenna is comprised of a spring-like spiral conductor that may be held in compression by a size and shape regulating outer nonconductive membrane. The assembly may be compressed and or extended to adjust the antenna for best performance in a particular situation. The assembly may be compressed into a generally flattened state for storage and or transportation, and extended at a later time for use. Accurate antenna dimensions and good performance are afforded by the use of high quality spring materials in conjunction with precise membrane dimensions.

主权项

1. A helical, circularly-polarized antenna assembly having a directional characteristic, comprising a backplane, a compression spring-form helical radiator of longitudinally tapered configuration, and a tensioned cover, whereby the tensioned cover is effective to compress and limit the spring-form tapered helical radiator to a tapered predetermined position during use.