IP Backbone Over Satellite
HDTV and other such high-bandwidth apps need to fly through the air if they don't want to be limited to cable and DSL subscribers, so figuring out how to make that happen is a lucrative business. Toward that end, Broadcom is demonstrating its 8PSK Turbo Coding System at IBC this week in Amsterdam, which it says increases throughput for advanced satellite broadcast services up to 50% over a commercial satellite link. The demonstration features an actual satellite connection, and is intended to show off Broadcom's collaboration with Sencore, who developed the satellite modem, and Xantic, who offers the IP data backbone connectivity via satellite. Broadcom says that, in addition to satellite TV broadband applications, the 8PSK system can be used to distribute data for IP backbone applications, TV distribution to cable headends, and other point-to-point data link applications. The 8PSK system used in the demonstration was built using Broadcom's BCM4500 Advanced Modulation Receiver and BCM3440 CMOS Satellite TV Tuner chips. The demonstration modem design is based on Sencore's ASM988 Advanced Satellite Modulator, which is now available for the digital audio/video markets. Sencore's modem design incorporates Broadcom modulator and demodulator technology and is said to provide data rates ranging from 1Mbaud to 30Mbaud. The modems used in the IBC demonstration system run downstream at 4Mbaud and upstream at 1Mbaud. The modems will communicate to the uplink station located at Xantic's teleport facility in Hilversum (The Netherlands) and will connect to the KPNQwest IP backbone via an RS530 data interface. At IBC, where the downlink station is located, the RS530 data interface will also be used to connect a PC via a router. For connection to the satellite dish, each modem will have a 70 MHz IF output and an L-band input.