Satellite-to-Earth 12 GHz fade slope analysis at a tropical location

In satellite transmissions at frequencies above 10 GHz, e.g., Ku-band and Ka-band, deep signal fading, and hence severe outage, is mainly attributed to rain, especially in wet tropical regions. Uplink power control (UPC) is one of the effective forms of fade countermeasure. Statistics of fade duration and fade slope variations give a detailed insight for the design of VSAT systems, in particular, in choosing an economical link margin and a suitable adaptive power control subsystem. The paper presents a year's worth of fade slope data measured from an equatorial mountainous coastal location. Two earlier papers (Pan, Q.W. et al., Proc. TRLabs/IEEE Wireless, vol.2, p.428-35, 2003; IEEE APS/URSI Int. Symp. Antennas & Propag. Conf. Dig., vol.2, p.1656-9, 2004) dealt mainly with joint excesses, fade durations, site-diversity and time-diversity.