Highly shaped satellite antenna for constant flux illumination of the earth from low orbits

The paper concerns with the design and measurement of a highly shaped, circularly polarized X-band antenna for working on an environmental satellite in a low polar orbit (about 800 km height). The work was performed as a part of a subcontract under ESA´ Polar Platform Program where ANT is responsible for the X-Band-data transmission subsystem. The demand on constant flux on earth leads to an antenna pattern with a wide illumination angle (+/-60 deg.), a deep inlet in the centre region (about -10. dB) and a fast roll off outside the coverage area (slope: 35 dB/34.7 deg.). Studying various kinds of alternative concepts, a shaped rotational symmetric antenna fed by a corrugated feed raised as a proper solution.