A METHOD OF ENHANCING DATA TRANSFER

摘要

A method of enhancing data transfer in a communication system comprising a transmitter and at least one receiver comprises setting access criteria for at least first and second data sources (3, 4) to non-subscribed and subscribed modes respectively. The first and second data sources are transmitted on a single frequency communication channel (9) from the transmitter to the or each receiver; and the second data source comprises the same type of data as the first data source transmitted at a higher resolution, higher data rate, or enhanced quality. The first data source is decodable at receivers in both subscribed and non-subscribed mode. The second data source is decoded only at receivers operating in subscribed mode.