Apparatus and method for generating broadcast signal frame using layered division multiplexing
An apparatus and method for broadcast signal frame using layered division multiplexing are disclosed. An apparatus for generating broadcast signal frame according to an embodiment of the present invention includes a combiner configured to generate a multiplexed signal by combining a core layer signal and an enhanced layer signal at different power levels; a power normalizer configured to reduce the power of the multiplexed signal to a power level corresponding to the core layer signal; a time interleaver configured to generate a time-interleaved signal by performing interleaving that is applied to both the core layer signal and the enhanced layer signal; and a frame builder configured to generate a broadcast signal frame including a bootstrap and a preamble using the time-interleaved signal.
1. A method of generating a broad signal frame, comprising:
generating a multiplexed signal by combining a core layer signal and an enhanced layer signal at different power levels;
reducing power of the multiplexed signal by using a normalizing factor, which is applied to both the core layer signal and the enhanced layer signal, to a power level corresponding to the core layer signal;
generating a time-interleaved signal by performing time interleaving that is applied to both the core layer signal and the enhanced layer signal after combining the core layer signal and the enhanced layer signal; and
generating a broadcast signal frame including a bootstrap and a preamble using the time-interleaved signal,
wherein the bootstrap is located at the beginning of the broadcast signal frame and includes a symbol representing a structure of the preamble,
wherein the bootstrap is shorter than the preamble, and has a fixed length, and
wherein the symbol corresponds to a fixed-length bit string representing a combination of an Layer-1 (L1)-Basic Mode, a Fast Fourier Transform size, a guard interval length, and a pilot pattern of the preamble.
2. The method of claim 1 , wherein the generating the broadcast signal frame includes
generating the bootstrap;
generating the preamble; and
generating a super-imposed payload corresponding to the time-interleaved signal.
3. The method of claim 2 , wherein the symbol corresponds to a lookup table in which
a preamble structure corresponding to a second Fast Fourier Transform size is allocated prior to a preamble structure corresponding to a first Fast Fourier Transform size, the second Fast Fourier Transform size being less than the first Fast Fourier Transform size when L1-Basic Modes are the same.