in this paper, an interference management for multi-beam satellite network to enhance spectral efficiency is studied. first, a two-satellite for future generation satellite network using cognitive radio technology is provided.this network is composed of a secondary satellite and aprimary satellite where the primary satellite system does not suffer from severe destructive interferences coming fr...

This paper presents the design and simulation of a typical Ka band satellite beacon receiver for propagation experimentation. Using satellite beacon signal as a reference signal in satellite wave propagation study, is one of the most important methods. Satellite beacons are frequently available for pointing large antennas, but such signals can be used for measuring the effect of natural phenome...

In this work, the ability of advanced satellite interferometry to monitor pre-failure landslide behaviours and the potential application of this technique to Failure Forecasting Methods (FFMs) are analysed. Several limits affect the ability of the technique to monitor a landslide process, especially during the pre-failure phase (tertiary creep). In this study, two of the major limitations affec...

The history of satellite remote sensing nighttime lights traces it is roots back the U.S. Air Force Defense Meteorological Satellite Program (DMSP) which began flying polar orbiting satellites with cloud imaging sensors in 1970’s. meteorologists found that they could improve weather predictions visible and thermal band imagery. channels on early DMSP worked well daytime—but were unable to see c...

Centromeres are composed of long arrays of satellite repeats in most multicellular eukaryotes investigated to date. The satellite repeat-based centromeres are believed to have evolved from "neocentromeres" that originally contained only single- or low-copy sequences. However, the emergence and evolution of the satellite repeats in centromeres has been elusive. Potato (Solanum tuberosum) provide...

Arbuscular mycorrhizal fungi (AMF) are a group of obligate plant symbionts which can promote plant nutrition. AMF communities are diverse, but the factors which control their assembly in space and time remain unclear. In this study, the contributions of geographical distance, environmental heterogeneity and time in shaping AMF communities associated with Miscanthus giganteus (a perennial grass ...

Communication via satellite begins when the satellite is positioned in the desired orbital position. Ground stations can communicate with LEO (Low Earth Orbiting) satellites only when the satellite is in their visibility region. The ground station’s ideal horizon plane is in fact the visibility region under 0 ̊ of elevation angle. Because of natural barriers or too high buildings in urban areas,...