Abstract

Chapter 22

The two fields are interlaced to form a frame. Acolor television signal has two parts: the luminance signal and the chrominance signal. A black and white picture has only the luminance signal, The chrominance signal modulates subcarriers that are transmitted with the video signal.

CATV system

Headend equipment generates local video signals and receives signals from a variety of sources including off-the-air broadcasts, communication satellites, or microwave relay or fiber-optic connections from other providers. The trunk cable is equipped with broadband amplifiers that are equalized to carry the entire bandwidth.  

Hybrid Fiber Coax (HFC)

As cable technology improved, the bandwidth increased and more channels were added. As Internet traffic increases, the response time increases, generally in proportion to the number of subscribers.

The entertainment channels are applied to the distribution cable as always, but the Internet channels are combined to a lesser number of subscribers.

Videoconference

Videoconferencing has considerable appeal, primarily as a substitute for travel, but it has yet to become a mainstream application. With a stable private network in place, the quality is as good as ISDN. The Internet is not a suitable medium where true conference-quality video is required, so most external conferences will need an ISDN gateway.