Apparatus and method for sending and receiving broadcast signals

A method of transmitting a broadcast signal, the method comprising:

• bit interleaving core layer data of at least one core layer Physical Layer Pipe (PLP) for a core layer;
• bit interleaving enhanced layer data of at least one enhanced layer PLP for an enhanced layer;
• controlling a power ratio between the bit-interleaved core layer data and the bit-interleaved enhanced layer data;
• combining the core layer data and the enhanced layer data which the power ratio is controlled and outputting Layered Division Multiplexing (LDM) data;
• normalizing power of the LDM data;
• time-interleaving the LDM data which the power is normalized;
• generating a signal frame comprising a preamble and the time-interleaved LDM data, the preamble carrying signaling information;
• and
• performing an Orthogonal Frequency Division Multiplexing (OFDM) modulation on the signal frame,
• wherein the time-interleaving of the LDM data is performed based on the at least one core layer PLP,
• wherein the signaling information comprises PLP layer information for indicating whether a layer of a PLP is the core layer or the enhanced layer, and
• wherein when the PLP layer information indicates that the layer of the PLP is the core layer, the signaling information for the PLP comprises time interleaving parameter information, and when the PLP layer information indicates that the layer of the PLP is the enhanced layer, the signaling information for the PLP does not comprise the time interleaving parameter information.

A broadcast signal receiver, comprising:

• a receiver configured to receive a broadcast signal comprising a signal frame, wherein the signal frame comprises a preamble and Layered Division Multiplexing (LDM) data into which core layer data of at least one core layer Physical Layer Pipe (PLP) for a core layer and enhanced layer data of at least one enhanced layer PLP for an enhanced layer are layered division multiplexed, wherein the preamble carries signaling information that comprises PLP layer information for indicating whether a layer of a PLP is the core layer or the enhanced layer, and wherein when the PLP layer information indicates that the layer of the PLP is the core layer, the signaling information for the PLP comprises time interleaving parameter information, and when the PLP layer information indicates that the layer of the PLP is the enhanced layer, the signaling information for the PLP does not comprise the time interleaving parameter information;
• a frame parser configured to parse the signal frame in the broadcast signal and to output the LDM data;
• a time deinterleaver configured to time de-interleave the LDM data based on the at least one core layer PLP;
• a first bit deinterleaver configured to bit de-interleave the core layer data in the LDM data;
• a bit interleaver configured to bit interleave the bit-deinterleaved core layer data;
• a de-combiner configured to output the enhanced layer data by cancelling the bit interleaved core layer data from the LDM data;
• and
• a second bit deinterleaver configured to bit de-interleave the enhanced layer data,
• wherein a power ratio between the core layer data and the enhanced layer data is controlled based on injection level information included in the signaling information.

A method of receiving a broadcast signal, the method comprising:

• receiving the broadcast signal comprising a signal frame, wherein the signal frame comprises a preamble and Layered Division Multiplexing (LDM) data into which core layer data of at least one core layer Physical Layer Pipe (PLP) for a core layer and enhanced layer data of at least one enhanced layer PLP for an enhanced layer are layered division multiplexed, wherein the preamble carries signaling information that comprises PLP layer information for indicating whether a layer of a PLP is the core layer or the enhanced layer, and wherein when the PLP layer information indicates that the layer of the PLP is the core layer, the signaling information for the PLP comprises time interleaving parameter information, and when the PLP layer information indicates that the layer of the PLP is the enhanced layer, the signaling information for the PLP does not comprise the time interleaving parameter information;
• parsing the signal frame in the broadcast signal and outputting the LDM data;
• time de-interleaving the LDM data based on the at least one core layer PLP;
• bit de-interleaving the core layer data in the LDM data;
• bit interleaving the bit-deinterleaved core layer data;
• outputting the enhanced layer data by cancelling the bit interleaved core layer data from the LDM data;
• and
• bit de-interleaving the enhanced layer data,
• wherein a power ratio between the core layer data and the enhanced layer data is controlled based on injection level information included in the signaling information.