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On the datacasting scheme over Chinese DTTB systems using signal space diversity

To support the simultaneous transmission of multiple multimedia services with different quality of service (QoS) requirements within the same spectrum over digital television terrestrial broadcasting (DTTB) systems, datacasting approaches have been widely studied. In this paper, to improve the immunity to the fading in the mobile environment, a novel datacasting scheme for Chinese DTTB systems, namely digital television terrestrial multimedia broadcasting (DTMB), is proposed in a backward compatible manner. In this scheme, by taking advantage of the time-frequency domain physical sub-channel (PSC), the modulation method of the multi-dimensional rotated BPSK constellation mapping using the signal space diversity (SSD), which are backward compatible with DTMB systems, are addressed together with the iterative demapping and decoding technique. Simulations over Rayleigh channels show that the proposed scheme efficiently improves the mobile reception performance of newly-introduced services at acceptable complexity penalty meanwhile without any degradation in the existing DTMB receivers for terrestrial services.