Designed to operate over the full frequency range of 1.7 to 2.3 GHz, the AS-48915 Series is ideal as an S-Band telemetry antenna and is available in either RHC or LHC polarization.
This design was first utilized on the Solar Maximum Mission and the International Ultraviolet Explorer (IUE) for NASA Goddard. Customers have included Rockwell (classified platforms), Motorola, TRW (KOMPSAT andGeoLITE), and NASA Houston (International SpaceStation). By operating from 1.2 to 2.5 GHz with modified performance, the AS-48915 Series can also be used as a GPS antenna.
Its RF design configuration is a two-arm conical log-spiral radiating element fed at the tip by a compensated balun. The spiral cone angle and the tip and base diameters were selected to provide satisfactory operation over the operational frequency band. The complementary two-arm spiral is wound to provide an inherent circular polarization. This results in broad-lobed unidirectional circularly polarized radiation off the small end or apex of the cone.
The AS-48915 Series is ideal for applications where hemispherical coverage is required. The antenna is optionally provided with a six-inch diameter ground plane (as shown in the photograph).
