Common Information Multicast With Different Data Rates

The task of multicast is to deliver common information to all users in a group. However, these users' different channel qualities result in their decoding capabilities being different. Therefore, the multicast design faces a dilemma to convey common information in terms of different decoding capabilities. Motivated by this, a multicast transmission scheme is proposed in this paper. In the proposed scheme, the base station transmitter prescribes the modulation and coding scheme to be used, considering the difference between the better channel-case and worse channel-case users' decoding capabilities, and the adaptive hierarchical modulation promises that each users can process the received signals according to his own decoding capabilities.