A planar L-band transportable antenna

The establishment of an L-band mobile satellite communications system in Australia has created the need for an antenna suitable for transportable, semi-permanent and permanent installations. A new form of circularly polarised planar antenna has been developed for such applications. Mobile satellite communications systems are typically down-link limited, that is the link direction from satellite to the ground terminal is more critical than the uplink. Accordingly not only the antenna gain is important, but also its noise temperature. For transportable applications a good physical profile for packaging and transport is also essential. The particular requirements for the Australian system are a bandwidth of approximately 8% centered near 1600 MHz, right hand circular polarisation, and a system G/T of more than -14.0 dB/K.