Steerable L-band antennas for land mobile terminals

Abstract

European Space Agency is developing EMS (European Mobile System) land mobile system for voice and data communications. Two different antenna concepts have been realised for a mobile terminal. The first one is a rotating antenna consisting of two radiating elements. The second one is an electronic array antenna in which 12 radiating elements locate on the facets of a truncated pyramid. Several field trials have been performed in order to optimise the tracking software and to evaluate the behaviour of the antenna in different environmental conditions. The results show that the developed antenna is feasible from the cost and performance point of view for this application.

Applications Of Antenna Arrays To Mobile Communications, Part I: Performance Improvement, Feasibility, And System Considerations

“…Current developments in basic antenna elements suitable for building an array for vehicle antennas in a satelliteto-mobile communications system include microstrip patch antennas [177]- [180], a ring patch [181], slot antennas [182], [183], crossed dipole antennas [184], traveling-wavetype antennas [185], and spiral-shaped antennas [186]. Many of these variously shaped building-block antennas are fabricated using microstrip technology.…”

“…• a 12-element array mounted on a truncated pyramid with electronic steering capability with a gain of 10 dBi [185];…”

“…In the course of vehicle movement when the beam is not pointing correctly, the array is steered to achieve the perfect null in the difference beam. A variation on this scheme is implemented in [185] using an array operating at L-band. The results of the field trial indicate the feasibility of a low-cost antenna system [185].…”

“…A variation on this scheme is implemented in [185] using an array operating at L-band. The results of the field trial indicate the feasibility of a low-cost antenna system [185].…”