An Improved Power Estimation for Mobile Satellite Communication Systems

Byounggi KIM, Namgil LEE, Sangjin RYOO

Department of Computer Media, Hanyeong College, Yeosu, Korea.
Department of Information & Communication System, Ulsan Korea Polytechnic College, Ulsan, Korea.
Huneed Technologies, Gunpo-si, Korea.

DOI: 10.4236/ijcns.2009.23020                

Abstract

In this paper, in order to increase system capacity and reduce the transmitting power of the user's equipment, we propose a efficient power estimation algorithm consisting of a modified open-loop power control (OLPC) and closed-loop power control (CLPC) for mobile satellite communications systems. The improved CLPC scheme, combining delay compensation algorithms and pilot diversity, is mainly applied to the ancillary ter-restrial component (ATC). ATC link in urban areas, because it is more suitable to the short round-trip delay (RTD). In the case of rural areas, where ATCs are not deployed or where a signal is not received from ATCs, transmit power monitoring equipment and OLPC schemes using efficient pilot diversity are combined and ap-plied to the link between the user's equipment and the satellite. Two modified power control schemes are ap-plied equally to the boundary areas where two kinds of signals are received in order to ensure coverage conti-nuity. Simulation results show that the improved power control scheme has good performance compared to conventional power control schemes in a geostationary earth orbit (GEO) satellite system utilizing ATCs.

Keywords

Power Control, Pilot Diversity, ATC

Conflicts of Interest

The authors declare no conflicts of interest.

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