Downlink Performance
Shkëlzen Cakaj · 2022
Satellite communication systems are particularly susceptible to noise because of their inherent low received power, more concretely too low receive signal power at the low Earth orbit receiving ground station. An alternative but equivalent way of expressing the noisiness of the equipment and line loss is through noise temperature. This chapter looks at antenna noise temperature and its impact on Figure of Merit. The idea is to compare the Figure of Merit under the case of medium attenuation presence, to the ideal case without medium attenuation, leaving the equipment structure completely unchanged. The chapter argues that the rain impacts on wave power propagated through the rain medium, and it is manifested as the signal power attenuation. At the single-antenna concept, the separation of the transmission and reception is achieved by means of duplexer. Due to the full duplex operation, the uplink signal is permanently present while the downlink is receiving data from the satellite.