Backward Compatible Multiservice Transmission Over the DTMB System

In this paper, a backward compatible multiservice transmission scheme over the digital television terrestrial multimedia broadcasting (DTMB) system is proposed, which is based on embedded constellation and bit division multiplexing. With the proposed scheme, simultaneous transmission of original services and multiple augmented services can be supported in the DTMB system in a backward compatible manner. No additional RF spectrum is required and no additional complexity is introduced to the legacy DTMB receivers. Two schemes over the DTMB system are proposed toward two different requirements, which are maintaining the transmission rate of original services and maintaining the reception SNR-threshold of original services, respectively. Average mutual information analysis and bit error ratio simulations are performed. In both schemes, the increment in the throughput of the DTMB system can be over 7.6 Mb/s in typical mode.