145 It is recognized that rain attenuation is the primary factor in the degradation of Earth-satellite communication at the Ka band frequency. The beacon signal of the ROCSAT-1 is set at 19.5 GHz for downlink and 28.5 GHz for uplink. ROCSAT-1 is the low earth orbit (LEO) satellite with a circular orbit at the altitude of 600 km and 35° inclination angle and scheduled to be launched at the begin...

When planning the link budget for millimetre and sub-millimetre wave telecommunications links, the attenuation by atmospheric gasses is taken into account. However, at millimetric frequencies above 50 GHz, it may become necessary to account for the temporal variations in absorption when calculating fade margins. Attenuation due to atmospheric absorption varies with temperature, barometric press...

As rainfall constitutes the main source of water for the terrestrial hydrological processes, accurate and reliable measurement and prediction of its spatial and temporal distribution over a wide range of scales is an important goal for hydrology. We investigate the potential of ground-based weather radar to provide such measurements through a theoretical analysis of some of the associated obser...

Among other atmospheric regions, ionosphere, which is ionized region of the atmosphere, is considered to impose serious limitations on satellite communication while the effect of other layers, more especially, the troposphere is often treated as negligible. At higher frequencies, radio waves pass through the ionosphere and are attenuated due to the free electrons present in ionosphere. However,...

Satellite beacon is a signal which does not modulated and sent to ground in constant frequency with specific designed power. Beacon signals are used by station antenna users track the satellite easily. The operators generally choose at Ku Band band since this more resistant rain attenuation. system performance describe contribute of rainfall rate This paper includes comparison attenuation takin...

The knowledge of 1-minute integrated cumulative rain rate distribution is required for predicting the attenuation induced by rain on satellite and terrestrial microwave and millimetric links. In this paper, conversion coefficients are derived for estimating the equivalent 1minute rain rate statistics from those available in 5 and 30-minutes over Akure, South-Western Nigeria. The derivation is b...

The design and performance of a rain fade simulation! counteraction system on a laboratory simulated 30/20 GHz, time division multiple access (IDMA) satellite communications testbed is evaluated. Severe rain attenuation of electromagnetic radiation at 30/20 GHz occurs due to the carrier wavelength approaching the water droplet size. Rain in the downlink path lowers the signal power present at t...