Interoperability in digital broadcasting systems

The introduction of advanced digital television coding and transmission techniques has enabled the delivery of advanced services directly to the home on a number of media. New digital services will require considerable software support and any receiver will be more complex than that needed for current analogue services. The standards adopted for digital television systems include MPEG for the source coding, DVB (Europe and elsewhere) and ATSC (USA) for the transmission modulation schemes for different media and some proprietary technology for conditional access and receiver software elements. The standards are complex, but necessarily so in order to support the flexibility of the technology and its wide scope, and take the form of "tool kits" whose components are complementary and can be used in sub-sets by the users to support many different service types. Such users can be broadcasters or telecommunications network operators or even computer system operators as a result of the converging influence of digitally coded information being a common format for all these users. This means that the selection of the standards and their subsets is itself a complex matter and leads to a significantly more demanding test regime prior to and after launch of services. Interoperability among different service providers and the receivers is a particular challenge, especially because different operating regimes are employed by players in the same market. The example of the UK is used to illustrate the issues arising in the testing environment brought about by digital broadcasting.