Data processing apparatus and data processing method
The present technology relates to a data processing apparatus and a data processing method which can enhance multipath propagation resistance. When performing modulation processing on a physical layer frame including a preamble, which includes a modulation parameter, and one or more subframes, which include data, the data processing apparatus can set any modulation parameter for each subframe, and the modulation parameter has a relationship of Tu i /Dx i ≥Tu i+1 /Dx i+1 in a case where an effective symbol length indicating a length of an effective symbol is Tu i and an interval between pilot signals in a frequency direction is Dx i in an i-th (i is an integer equal to or greater than 0) subframe. The present technology can be applied to, for example, data transmission compliant to a broadcast standard such as ATSC 3.0.
1. A data processing apparatus, comprising:
processing circuitry configured to:
set modulation parameters for a physical layer frame;
include the modulation parameters in the physical layer frame; and
perform modulation processing on subframes of the physical layer frame according to the modulation parameters, wherein
the subframes of the physical layer frame include a first subframe and a second subframe arranged after the first subframe in a time direction, and
the modulation parameters are set such that
a first ratio between a first effective symbol length of a first effective symbol in the time direction for the first subframe and a first interval between first pilot signals in a frequency direction for the first subframe is equal to or greater than a second ratio between a second effective symbol length of a second effective symbol in the time direction for the second subframe and a second interval between second pilot signals in the frequency direction for the second subframe,
the first effective symbol length is greater than the second effective symbol length, and
a first fast Fourier transform (FFT) size applicable to the first subframe is greater than a second FFT size applicable to the second subframe.
2. The data processing apparatus according to claim 1 , wherein
the physical layer frame further includes a preamble,
the first subframe is arranged immediately after the preamble in the time direction, and
the modulation parameters are set such that
a third ratio between a third effective symbol length of a third effective symbol in the time direction for the preamble and a third interval between third pilot signals in the frequency direction for the preamble is equal to or greater than the first ratio.
3. The data processing apparatus according to claim 1 , wherein the physical layer frame further includes a bootstrap arranged at a head portion of the physical layer frame.
4. The data processing apparatus according to claim 1 , wherein
the modulation processing is performed according to orthogonal frequency division multiplexing (OFDM), and
the physical layer frame includes a plurality of OFDM symbols.
5. The data processing apparatus according to claim 1 , wherein
the physical layer frame further includes a preamble, and
a third effective symbol length of a third effective symbol in the time direction for the preamble is greater than the first effective symbol length for the first subframe.
6. A data processing apparatus, comprising:
processing circuitry configured to:
set modulation parameters for a physical layer frame;
include the modulation parameters in the physical layer frame; and
perform modulation processing on subframes of the physical layer frame according to the modulation parameters, wherein
the subframes of the physical layer frame include a first subframe and a second subframe arranged after the first subframe in a time direction, and
the modulation parameters are set such that
a first interval between first pilot signals in a frequency direction for the first subframe is less than a second interval between second pilot signals in the frequency direction for the second subframe, and
a first fast Fourier transform (FFT) size applicable to the first subframe is same as a second FFT size applicable to the second subframe.
7. A data processing apparatus comprising:
processing circuitry configured to:
receive a physical layer frame that includes subframes;
obtain modulation parameters for the physical layer frame; and
perform demodulation processing on the subframes of the physical layer frame according to the modulation parameters,
wherein
the subframes of the physical layer frame include a first subframe and a second subframe arranged after the first subframe in a time direction, and
the modulation parameters are set such that
a first ratio between a first effective symbol length of a first effective symbol in the time direction for the first subframe and a first interval between first pilot signals in a frequency direction for the first subframe is equal to or greater than a second ratio between a second effective symbol length of a second effective symbol in the time direction for the second subframe and a second interval between second pilot signals in the frequency direction for the second subframe,
the first effective symbol length is greater than the second effective symbol length, and
a first fast Fourier transform (FFT) size applicable to the first subframe is greater than a second FFT size applicable to the second subframe.
8. The data processing apparatus according to claim 7 , wherein
the physical layer frame further includes a preamble,
the first subframe is arranged immediately after the preamble in the time direction, and
the modulation parameters are set such that
a third ratio between a third effective symbol length of a third effective symbol in the time direction for the preamble and a third interval between third pilot signals in the frequency direction for the preamble is equal to or greater than the first ratio.
9. The data processing apparatus according to claim 7 , wherein the physical layer frame further includes a bootstrap arranged at a head portion of the physical layer frame.
10. The data processing apparatus according to claim 7 , wherein
the demodulation processing is performed according to orthogonal frequency division multiplexing (OFDM), and
the physical layer frame includes a plurality of OFDM symbols.
11. The data processing apparatus according to claim 7 , wherein
the physical layer frame further includes a preamble, and
a third effective symbol length of a third effective symbol in the time direction for the preamble is greater than the first effective symbol length for the first subframe.