| 摘要 |
PROBLEM TO BE SOLVED: To automatically compensate for signal losses that occur for video signals transmitted over appreciable distances via conductors including twisted-pair cables. SOLUTION: A reference signal having a known form and strength (e.g., a pulse signal) is provided to each pair of conductors carrying a component of a video signal from a transmitter to a receiver. The receiver includes adjustable gain amplifiers for each conductor pair over which a component of the video signal is transmitted. The gains of the amplifiers are initially set at an initial level (e.g., their maximum gain) to enable detection of the reference signal. Once the reference signal is detected in a conductor pair, the amplifier gains are adjusted such that the level of the reference signal is restored approximately to its original form and strength. The apparatus for the automatic compensation is particularly applicable to the transmission of video over long lengths of CAT-5 or similar twisted-pair cables. COPYRIGHT: (C)2008,JPO&INPIT
|
