the research used the satellite image (landsat 7 etm ) within the thermal infrared sixth band (tir6) and geographic information system (gis) to determine the air pollution and its relationship with the land cover (lc) and land use (lu) of baghdad city. concentration of total suspended particles (tsp), lead (pb), carbon oxides (co, co2), and sulphur dioxide (so2) were obtained from 22 ground mea...

With the exponential growth of the internet, wireless networks such as satellite networks are becoming increasingly popular. The characteristics of satellite networks such as long latency, large delay-bandwidth product, high bit error rate over satellite links and variable round trip time, severely degrade TCP/IP performance. At the conjunction of the satellite link and the fixed link, the base...

The International Maritime Satellite (Inmarsat) communication service can be used to provide a wide area network (WAN) connection for a local area network (LAN) to the home LAN from almost anywhere on the earth. The communication link of the WAN connection is achieved through the satellite network of Inmarsat and a land-earth digital telephone network, such as Integrated Services Digital Networ...

The accuracy of the link of the proper motion system of astrometric satellite missions like AMEX and GAIA is discussed. Monte-Carlo methods were used to simulate catalogues of positions and proper motions of quasars and galaxies to test the link. The main conclusion is, that future satellite missions like GAIA may be “self-calibrated” by their measurements of QSOs, while additional measurements...

This study presents the “overview of TCP performance on satellite communication networks”, aimed at satellite characteristics, their effects on throughput selected link control protocols and various method proposed for enhancing TCP throughput on satellite networks. Literature reviews on satellite link characteristics and their effects on TCP operation in satellite communication networks. Diffe...

Iran Telecommunication Research Centre Summary In this paper the efficiency of linearization for pre-distortion in 64-QAM modulation, utilized in Ka-band satellite link for DVB-RCS services, is investigated. The linearization is simulated by Matlab-Simulink, for a GEO Satellite and DVBRCS service. A TWTA power amplifier with 1dB back-off is used in this satellite link, and to conclude the resul...

Satellite communications (SatComs) recently, have admitted as a new technological advances that attracted and raised special investment ventures. Space communication technology has found many application areas from costly, one-of-a-sort structures, to utilize again of on sequential tasks, the progress canonical protocols accepted by space agencies lots countries. one important technologies for ...

With regard to the limited link time of the inter-satellite links in LEO satellite constellation network, this paper proposes a routing algorithm which takes the limited link time into account, and supports traffic engineering. The routing algorithm is based on MPLS satellite network. The initial weight of links is defined to be function of residual bandwidth and link time. And during the weigh...

Satellite networks are going to play an important role in the global information infrastructure. Satellites can be used to provide Internet services to fixed users and to mobile users. However, recent measurements show that the satellite link efficiency is only about 30%. In order to improve the performance of Internet over satellite, a new protocol called Receiver Window Backpressure Protocol ...