Dynamic configuration of a flexible orthogonal frequency division multiplexing PHY transport data frame

• US 10,574,500 B2
• Filed: 02/07/2019
• Issued: 02/25/2020
• Est. Priority Date: 08/07/2014
• Status: Active Grant

• Current Assignee: One Media LLC (Sinclair, Inc.)
• Original Assignee: One Media LLC (Sinclair, Inc.)
• Inventors: Simon, Michael J., Shelby, Kevin A., Earnshaw, Mark
• Primary Examiner(s): Perez, James M
• Application Number:
  US16/269,698
• Publication Number:
  US 20190268195A1
• Time in Patent Office: 383 Days
• Field of Search: 375259-285
• CPC Class Codes: H04L 27/26025 Numerology, i.e. varying one or more of symbol duration, subcarrier spacing, Fourier transform size, sampling rate or down-clocking allocating sub-channels of the transmission path H04L5/003
• CPC Class Codes: H04L 27/2607 Cyclic extensions
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/003 Arrangements for allocating sub-channels of the transmission path
• CPC Class Codes: H04W 72/30 Resource management for broadcast services
• CPC Class Codes: H04W 88/16 Gateway arrangements

Abstract

A base station may generate and transmit a transport stream including a sequence of frames. A frame may include a plurality of partitions, where each partition includes a corresponding set of OFDM symbols. For each partition, the OFDM symbols in that partition may have a corresponding cyclic prefix size and a corresponding FFT size, allowing different partitions to be targeted for different collections of user devices, e.g., user devices having different expected values of maximum delay spread and/or different ranges of mobility. The base station may also dynamically re-configure the sample rate of each frame, allowing further resolution in control of subcarrier spacing. By allowing the cyclic prefixes of different OFDM symbols to have different lengths, it is feasible to construct a frame that confirms to a set payload duration and has arbitrary values of cyclic prefix size per partition and FFT size per partition. The partitions may be multiplexed in time and/or frequency.

Claims

1. A method for transmitting broadcast time domain symbols in a broadcast system, the method comprising:

assigning a first set of subcarriers to a first Physical Partition Data Channel (PPDCH) of an orthogonal frequency domain multiplexing (OFDM) symbol;

assigning a second set of subcarriers to a second PPDCH of the OFDM symbol;

generating frequency domain OFDM data by frequency domain multiplexing the first PPDCH with the second PPDCH without intra-symbol frequency interleaving the first set of subcarriers of the first PPDCH with the second set of subcarriers of the second PPDCH;

repeating the frequency domain multiplexing over a plurality of OFDM symbols to form a data frame;

generating the broadcast time domain symbols associated with the data frame; and

wirelessly transmitting the broadcast time domain symbols.

2. The method of claim 1, wherein the first set of subcarriers, in the frequency domain OFDM data, comprises a first contiguous set of subcarriers.

3. The method of claim 2, wherein the second set of subcarriers, in the frequency domain OFDM data, comprises a second contiguous set of subcarriers different than the first contiguous set of subcarriers.

4. The method of claim 1, wherein the generating frequency domain OFDM data comprises frequency domain multiplexing the first PPDCH with the second PPDCH such that the second set of subcarriers is contiguous to the first set of subcarriers.

5. The method of claim 1, further comprising:

identifying the first PPDCH using a first subcarrier of the first set of subcarriers; and

identifying the second PPDCH using a first subcarrier of the second set of subcarriers.

6. The method of claim 1, wherein the first set of subcarriers is a first subset of subcarriers associated with the OFDM symbol and the second set of subcarriers is a second subset of the subcarriers associated with the OFDM symbol.

7. The method of claim 1, wherein the generating the broadcast time domain symbols further comprises converting the frequency domain OFDM data to the broadcast time domain symbols using an inverse Fourier transform having a transform size.

8. The method of claim 7, wherein the generating the broadcast time domain symbols further comprises generating a cyclic prefix for the broadcast time domain symbols using a cyclic prefix size.

9. A computer program product for transmitting broadcast time domain symbols in a broadcast system, the computer program product comprising one or more non-transitory computer-readable storage devices having stored thereon computer executable instructions that when executed cause at least one processor to:

assign a first set of subcarriers to a first Physical Partition Data Channel (PPDCH) of an orthogonal frequency domain multiplexing (OFDM) symbol;

assign a second set of subcarriers to a second PPDCH of the OFDM symbol;

generate frequency domain OFDM data by frequency domain multiplexing the first PPDCH with the second PPDCH without intra-symbol frequency interleaving the first set of subcarriers of the first PPDCH with the second set of subcarriers of the second PPDCH;

repeat the frequency domain multiplexing over a plurality of OFDM symbols to form a data frame;

generate the broadcast time domain symbols associated with the data frame; and

cause the broadcast time domain symbols to be wirelessly transmitted.

10. The computer program product of claim 9, wherein the first set of subcarriers, in the frequency domain OFDM data, comprises a first contiguous set of subcarriers.

11. The computer program product of claim 10, wherein the second set of subcarriers, in the frequency domain OFDM data, comprises a second contiguous set of subcarriers different than the first contiguous set of subcarriers.

12. The computer program product of claim 9, wherein to generate the frequency domain OFDM data the processor is configured to frequency domain multiplex the first PPDCH with the second PPDCH such that the second set of subcarriers is contiguous to the first set of subcarriers.

13. The computer program product of claim 9, wherein the processor is further configured to:

identify the first PPDCH using a first subcarrier of the first set of subcarriers; and

identify the second PPDCH using a first subcarrier of the second set of subcarriers.

14. The computer program product claim 9, wherein the first set of subcarriers is a first subset of subcarriers associated with the OFDM symbol and the second set of subcarriers is a second subset of the subcarriers associated with the OFDM symbol.

15. The computer program product claim 9, wherein to generate the broadcast time domain symbols, the processor is configured to:

convert the frequency domain OFDM data to the broadcast time domain symbols using an inverse Fourier transform having a transform size; and

generate a cyclic prefix for the broadcast time domain symbols using a cyclic prefix size.

16. An apparatus for transmitting broadcast time domain symbols in a broadcast system, the apparatus comprising:

a processor configured to;

assign a first set of subcarriers to a first Physical Partition Data Channel (PPDCH) of an orthogonal frequency domain multiplexing (OFDM) symbol;

assign a second set of subcarriers to a second PPDCH of the OFDM symbol;

generate frequency domain OFDM data by frequency domain multiplexing the first PPDCH with the second PPDCH without intra-symbol frequency interleaving the first set of subcarriers of the first PPDCH with the second set of subcarriers of the second PPDCH;

repeat the frequency domain multiplexing over a plurality of OFDM symbols to form a data frame; and

generate the broadcast time domain symbols associated with the data frame; and

a transmitter configured to wirelessly transmit the broadcast time domain symbols.

17. The apparatus of claim 16, wherein the first set of subcarriers, in the frequency domain OFDM data, comprises a first contiguous set of subcarriers, and wherein the second set of subcarriers, in the frequency domain OFDM data, comprises a second contiguous set of subcarriers different than the first contiguous set of subcarriers.

18. The apparatus of claim 16, wherein to generate the frequency domain OFDM data, the processor is configured to frequency domain multiplex the first PPDCH with the second PPDCH such that the second set of subcarriers is contiguous to the first set of subcarriers.

19. The apparatus of claim 18, wherein the first set of subcarriers is a first subset of subcarriers associated with the OFDM symbol and the second set of subcarriers is a second subset of the subcarriers associated with the OFDM symbol.

20. The apparatus of claim 16, wherein to generate the broadcast time domain symbols, the processor is configured to:

convert the frequency domain OFDM data to the broadcast time domain symbols using an inverse Fourier transform having a transform size; and

generate a cyclic prefix for the broadcast time domain symbols using a cyclic prefix size.