Internet services via direct broadcast satellites
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High-power direct broadcast satellites (DBS) can be used to downlink high volumes of data and services available in the Internet directly to home terminals. Setting up an asymmetric system, using the telephone network, a similar low speed terrestrial network or a satellite return link for accessing an Internet service provider (ISP) and using one or more channels on a DBS to transmit large amounts of data to the end user makes this system a high-speed interactive one. After implementation of a laboratory platform using a satellite simulator, the concept was implemented using an audio subcarrier of a standard TV transponder which provides a bit rate of 192 kbit/sec. This IDBS A system has successfully been used for implementing a set of applications and demonstrations. In the second phase, VSATs operating at between 64 Kbit/sec and 2Mbit/sec have been used for IDBS V. Initial tests using the upcoming DVB/MPEG-2 program stream for providing high speed multimedia Internet services via satellite (IDBS D) at data rates of 2 to 8 Mbit/sec were carried out successfully. This paper presents the architecture of the system hardware and software and reports on the performance observed for the various data services and applications available on IDBS A and IDBS V systems. It also comments on measurements and analyses of the systems performance and outlines the status of the ongoing developments for IDBS D.