Method and apparatus for transmitting/receiving multimedia broadcast/multicast data based on hierarchical modulation

摘要

The present invention relates to a communication field and particularly to a method and apparatus for transmitting/receiving multimedia broadcast/multicast data based on hierarchical modulation in order to solve the problem of low efficiency of conventional methods. The method includes the steps of: receiving a check report returned from a receiver, determining whether the check report indicates there are both basic layer and enhanced layer data errors and if yes, exchanging the last two bits of the enhanced layer and the first two bits of the basic layer and modulating the data with a second constellation map and then transmitting the data; otherwise determining whether the check report indicates there is only the basic layer error and if yes, modulating the data with the second constellation map in the order from the basic layer to the enhanced layer and then transmitting the data; if there is only enhanced layer error, exchanging the last two bits of the enhanced layer and the first two bits of the basic layer and modulating the data with the first constellation map and then transmitting the data. The beneficial effects of the present invention are that the retransmission efficiency can be improved and the ratio of receiving the data correctly by the users at the cell center and at the cell border during the first retransmission is improved.