摘要 |
A method and system are described for communicating data from a central station to a plurality of subscribers using conventional television signal format. Individual television scan lines in a television frame are preassigned to convey data to particular subscribers. The preassignment of a television scan line may be, with respect to a portion of a line, one entire line or a multiple of scan lines, depending upon the data requirements of the respective subscribers. For address identification by these subscribers these television scan lines occupy predetermined positions in the television frame. A two-way communication system is provided whereby the subscribers may each return to the central station data transmissions on a different channel or carrier frequency using single or multiple television scan lines. The return transmissions are so timed from the several subscribers that they arrive in a predetermined sequence at the central station in synchronization with the television scan line transmissions from the central station to the subscribers. Conventional television techniques and devices may be used to form a communication system in accordance with the invention.
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