Performance evaluation of planar antenna arrays onboard low earth orbit satellites

Earth orbit satellite (LEOS) systems offer continuous service using constellations, which stand out for their global coverage capacity, broadcast and ability to support user mobility. However, the low gain offered by omnidirectional antennas, as well as the large number of handovers within the satellite footprint due to the use of sector and spot beam antennas, along with the short satellite viewing time from the earth stations (ES), waste satellite power and degrades communications link quality. In this paper we present the use of a planar array antenna to establish communication links between LEOS and ES, allowing a more efficient use of satellite power and an increase in digital communications performance. The continuous steering of the antenna array radiation pattern (direction of arrival, DOA), adaptively directs the main lobe onboard the satellite towards the desired direction over the earth, allowing longer visibility time. A more directive downlink beam is obtained, increasing antenna gain and improving the bit error rate (BER) probability within quality of service (QoS) limits.