Apparatus and method for transmitting and receiving broadcasting signal

摘要

A broadcasting signal transmitting method of a broadcasting signal transmitting apparatus is provided. According to the method, a base layer signal including a plurality of subchannels that include a base layer symbol is generated, and an enhancement layer signal including an enhancement layer symbol is generated. In a first subchannel corresponding to a section in which the enhancement layer signal has data among a plurality of subchannels, a hierarchical modulation symbol is generated by hierarchically modulating the base layer symbol and the enhancement layer symbol in accordance with a hierarchical modulation index. In a second subchannel corresponding to a section in which the enhancement layer signal does have not data among the plurality of subchannels, the base layer symbol is outputted. The broadcasting signal including the hierarchical modulation symbol of the first subchannel and the base layer symbol of the second subchannel is transmitted.