ABSTRACT

Asian Internet Interconnection Initiatives (AIII) is a series of research activities performed on the test bed, constructed using Ku band star shaped VSAT network provided by JCSAT-3 communication satellite. For countries where only AIII project provides Internet connectivity, the stable operation of AIII satellite link is greatly desired. Therefore in this research study, in order to obtain such operation, the effect of rain on AIII satellite link is analyzed.

Rain attenuation at different rain rates are determined using Garcia Model and exceeded percentage of a year for different rain rates is evaluated following CCIR Report 563. Then, in order to obtain clear view on operating limit of AIII-AIT satellite link in terms of rain rates, threshold rain rate, the rain rate up to which the reliable operation of satellite link can be maintained and threshold outage time, the maximum outage time of the satellite link are determined for different possible information bit rates of 1.536 Mbps (H11), 1.920 Mbps (H12), 0.384 Mbps (H0), 1.544 Mbps (T1) and 2.0488 Mbps (E1) and coding rates of 1/2 and 3/4. The designed bit rate and coding rate of AIII-AIT satellite are 1.536 Mbps (H11) and 3/4 respectively.

From this study, it is understood that the stable operation of designed AIII-AIT satellite link can be found up to 38 mm/h and 21 mm/h of Bangkok and Japan rain respectively. Also, simply changing coding rate to 1/2 from operating 3/4, only in rainy season, the more stable operation satellite link can be achieved.

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