Design of two high gain, low profile helical antennas for operation at 918 MHZ

Abstract

Two helical antennas were designed, fabricated and tested to permit tanks or tracked vehicles to function with a high gain, low profile antenna field pattern for a telemetry system operating at 518 MHz. The electrical properties of the helical antennas were compared to the system's dipoie antennas in an attempt to enhance the operating performance of the RMS II/SCORE system. Field measurements were made under the controlled conditions of an antenna field pattern range and while the RMS II system was operational. Antenna properties of gain, beamwidth and efficiency as well as physical size and installation locations were considered for possible inclusion of helical antennas in the telemetry system.