HDTV-Reviews.co.uk

Wednesday, 31 May, 2006

HD channels stretch cable’s bandwidth

Despite their huge bandwidth, cable television lines are running out of room due to the transmission of extensive high defintion content.

Cable operators’ wires are so packed with TV channels and new services, including video on demand, broadband Internet and phone, that many are strugling to find bandwidth for the new wave of high defintion channels.

Craig Moffett of Sanford C. Bernstein, the US-based research company said: “Cable operators need massive capacity for HDTV, and have to move quickly. HDTV is hot.”

Satellite and phone companies will be keen to move in and try to corner the market.

“Satellite’s going to be constrained not so much by how many channels they can carry than by how many they can get,” says Bob Scherman, Satellite Business News editor and publisher.

Meanwhile, phone company Verizon is building state-of-the-art, fiber-optic networks that it says can handle 210 HD services plus all the conventional US TV channels.

These newer rivals for cable have always been transmitting signals digitally, so neither of them has to worry about customers having"satellite-ready" or “phone-ready” TV sets. Their customers are used to needing a set-top box or receiver to convert the signals into images needed for analog sets that still dominate the home.

More important, being all-digital makes more efficient use of their capacity; about 10 standard digital channels fit into the bandwidth required for one analog channel.

By contrast, cable’s roots are analog, and they typically still offer analog transmissions of 70 or more of the most popular channels that the majority of their customers watch on “cable-ready” analog TV sets - without a box. Providing those analog signals eats up about two-thirds of a typical system’s bandwidth, even after the industry spent US$100 billion over a decade to string fatter lines to handle interactive services.

Due to that analog legacy, most cable operators have room to add only about a dozen HD channels.

It’s a competitive gap likely to widen with satellite companies likely to have “a two-to-three-year lead over cable during which they’ll be able to offer a materially higher number of HD channels,” Morgan Stanley’s Richard Bilotti writes.