Apparatus and method for sending and receiving broadcast signals
A broadcast signal transmitter includes an encoder configured to perform outer encoding and inner encoding on Physical Layer Pipe (PLP) data, a time interleaver configured to interleave the PLP data on which the outer encoding and the inner encoding are performed, a framer configured to generate a signal frame comprising the interleaved PLP data, the signal frame comprising a preamble and at least one subframe, a frequency interleave configured to interleave data comprised in the generated signal frame, a pilot inserter configured to insert Scattered Pilots (SPs) into the signal frame comprising the interleaved data, and a modulator configured to modulate the SPs inserted signal frame by Orthogonal Frequency Division Multiplexing (OFDM) modulation scheme.
1. A broadcast signal transmitter comprising:
an encoder configured to perform outer encoding and inner encoding on Physical Layer Pipe (PLP) data;
a time interleaver configured to interleave the PLP data on which the outer encoding and the inner encoding are performed;
a framer configured to generate a signal frame comprising the interleaved PLP data, the signal frame comprising a preamble and at least one subframe;
a frequency interleaver configured to interleave data comprised in the generated signal frame;
a pilot inserter configured to insert Scattered Pilots (SPs) into the signal frame comprising the interleaved data; and
a modulator configured to modulate the SPs inserted signal frame by an Orthogonal Frequency Division Multiplexing (OFDM) modulation scheme,
wherein an SP pattern of the SPs is defined by values of Dx and Dy, the Dx being a separation of pilot bearing carriers in a frequency direction and the Dy being a number of symbols forming one scattered pilot sequence in a time direction,
wherein an amplitude of the SPs is determined from a SP boosting parameter and the SP pattern of the SPs, and
wherein the preamble comprises the SP boosting parameter which corresponds to one of boosting levels for each of the at least one subframe, and the preamble further comprises pilot information about the SP pattern.
2. The broadcast signal transmitter of claim 1 , wherein the SP boosting parameter corresponds to one of five boosting levels for the SP pattern,
wherein boosted power of the SPs for a first level among the five levels and for each SP pattern (SPDx_Dy) is 0 dB, and
wherein boosted powers of the SPs for a fifth level of among the five levels and for each SP pattern are as follows: 2.90 dB for SP3_2, 4.40 dB for SP3_4, 3.60 dB for SP4_2, 5.10 dB for SP4_4, 4.60 dB for SP6_2, 6.00 dB for SP6_4, 5.30 dB for SP8_2, 6.60 dB for SP8_4, 6.20 dB for SP12_2, 7.50 dB for SP12_4, 6.80 dB for SP16_2, 8.20 dB for SP16_4, 7.70 dB for SP24_2, 9.10 dB for SP24_4, 8.40 dB for SP32_2, and 9.70 dB for SP32_4.
3. The broadcast signal transmitter of claim 1 , wherein:
the at least one subframe comprises at least one subframe boundary symbol, and
the at least one subframe boundary symbol comprises subframe boundary pilots and at least one null carrier.
4. The broadcast signal transmitter of claim 1 , wherein:
the preamble comprises preamble pilots,
the preamble pilots are transmitted at a boosted power level, and
a boosted amplitude of the preamble pilots is determined based on at least one of a Fast Fourier Transform (FFT) size, a Guard Interval (GI) length, and a pilot pattern of the preamble.
5. A method of transmitting a broadcast signal, the method comprising:
performing outer encoding and inner encoding on Physical Layer Pipe (PLP) data;
interleaving the PLP data on which the outer encoding and the inner encoding are performed;
generating a signal frame comprising the interleaved PLP data, the signal frame comprising a preamble and at least one subframe;
interleaving data comprised in the generated signal frame;
inserting Scattered Pilots (SPs) into the signal frame comprising the interleaved data; and
modulating the SPs inserted signal frame by an Orthogonal Frequency Division Multiplexing (OFDM) modulation scheme,
wherein an SP pattern of the SPs is defined by values of Dx and Dy, the Dx being a separation of pilot bearing carriers in a frequency direction and the Dy being a number of symbols forming one scattered pilot sequence in a time direction,
wherein an amplitude of the SPs is determined from a SP boosting parameter and the SP pattern of the SPs, and
wherein the preamble comprises the SP boosting parameter which corresponds to one of boosting levels for each of the at least one subframe, and the preamble further comprises pilot information about the SP pattern.
6. The method of claim 5 , wherein the SP boosting parameter corresponds to one of five boosting levels for the SP pattern,
wherein boosted power of the SPs for a first level among the five levels and for each SP pattern (SPDx_Dy) is 0 dB, and
wherein boosted powers of the SPs for a fifth level among the five levels and for each SP pattern are as follows: 2.90 dB for SP3_2, 4.40 dB for SP3_4, 3.60 dB for SP4_2, 5.10 dB for SP4_4, 4.60 dB for SP6_2, 6.00 dB for SP6_4, 5.30 dB for SP8_2, 6.60 dB for SP8_4, 6.20 dB for SP12_2, 7.50 dB for SP12_4, 6.80 dB for SP16_2, 8.20 dB for SP16_4, 7.70 dB for SP24_2, 9.10 dB for SP24_4, 8.40 dB for SP32_2, and 9.70 dB for SP32_4.
7. The method of claim 5 , wherein:
the at least one subframe comprises at least one subframe boundary symbol, and
the at least one subframe boundary symbol comprises subframe boundary pilots and at least one null carrier.
8. The method of claim 5 , wherein:
the preamble comprises preamble pilots,
the preamble pilots are transmitted at a boosted power level, and
a boosted amplitude of the preamble pilots is determined based on at least one of a Fast Fourier Transform (FFT) size, a Guard Interval (GI) length, and a pilot pattern of the preamble.