COMMUNICATION SYSTEM FOR SUPERIMPOSING DATA ONTO A VIDEO SIGNAL

摘要

A data communication system transmits a data signal that includes data that may be grouped into one or more packets. The packets may be further grouped into sessions where a session identifier for the session corresponds to the data contained in the session and a receiver can use the session identifier to decide to ignore the corresponding data. The system may include a provision for checking and correcting errors in digital data by partitioning the data into original data portions, applying an error-correction algorithm to provide error-corrected portions corresponding to the original data portions, and rearranging and concatenating the error-corrected portions to provide a string of bits. The communication protocols of the transmitter and receivers may be automatically and dynamically set by constructing a packet of data containing communication protocol parameters, transmitting the packet of data to the receivers, and adjusting communication protocol attributes according to the communication protocol parameters contained in the packet. Each of the receivers may include a board ID which, once assigned, cannot be ascertained and which allows selection of a subset of the receivers to receive the data. The data signal can be transmitted by being superimposed onto a conventional video signal, such as an NTSC video signal.