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Introduction

Most cable channel operators provide national or regional feeds from a single source to cable head end operators across the country and world. These feeds are transmitted via satellite from the broadcasters to the head ends. The head ends then distribute these feeds to viewers over cable. The Weather Channel is a unique broadcaster in that part of its presentation to viewers is localized to provide local weather observations and forecasts. It is not feasible to generate the content of these local forecasts at TWC and then distribute them over satellite to each of the head ends. There is just not enough bandwidth. Instead, a smart device known as a STAR is deployed in each head end. In addition to a national audio and video feed, TWC sends weather-related data to the STARs out in the field including local observations, thirty-six hour text forecasts, daily extended forecasts, radar images, and severe weather alerts. In addition, TWC can send software updates and other non-weather-related data over the satellite.

For example, every hour thousands of automated observation stations all over the United States sample the weather conditions at their location and transmit this data to the National Weather Service (NWS). Most STARs in the field are assigned an observation point. TWC receives this data from NWS and then sends it over the satellite where it is received by each of the STARs. Each STAR saves any data that is relevant to its configuration and discards the rest. The STAR may then display those observations either on top of the national feed in a small bar at the bottom of the screen, or it may render a full-screen presentation.

Currently TWC broadcasts its feed as an analog NTSC signal for the core network. TWC has started migrating to a digital MPEG signal to meet the demands of the cable industry as it begins the migration to digital. As part of this move, TWC is deploying a next generation STAR device known as the IntelliStar.


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Next: What is an IntelliStar Up: Using FreeBSD to Render Previous: Using FreeBSD to Render