| 摘要 |
A television transmission system for asynchronously transmitting a television picture as a plurality of video samples over a narrow bandwidth medium from at least one remote transmitting site to a receiver at a base station. Improved synchronization between the transmitter and receiver are achieved by a dotting pattern consisting of alternating logic ones and zeros being sent by the transmitter to precede the video samples such that a sampling clock at the receiver synchronizes to the phase of the dotting pattern and thereafter samples the video signal. The video signals are also preceded by at least one predetermined digital word which identifies the particular remote transmitter and prepares the receiver to begin receiving the video samples. DC restoration circuitry determines the average value of the incoming video signals and to add an appropriate DC offset to the video signals to correct for any change in the gray scale of the video samples. A Barker word detector accurately points to the first video sample of the transmitted signal.
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