Detecting format of data
View Patent ↗A method for detecting a format of data in a wireless local area network and a device using the same are provided. The device receives a physical layer protocol data unit (PPDU) that includes a first field and a second field. The device determines a first format of the PPDU based on at least one of the first field and the second field and determines a second format of the PPDU based on a modulation phase of the PPDU.
1. A method for transmitting a physical layer protocol data unit (PPDU) in a wireless local area network, the method comprising:
generating a PPDU, the PPDU comprising a first short training (ST) field, a first channel estimation (CE) field, a header field, a second ST field, a second CE field, a data field and a training (TRN) field; and
transmitting the PPDU,
wherein the header field comprises a stream field indicating a number of spatial streams,
wherein the second CE field comprises a number of symbols, the number of symbols for the second CE field determined based on the number of spatial streams of the header field,
wherein the second CE field generated from a first mapping matrix, the first mapping matrix having a number of columns, the number of columns corresponding to the number of symbols for the second CE field,
wherein the TRN field comprises a plurality of TRN subfields, each TRN subfield comprising a number of symbols, each TRN subfield generated from a second mapping matrix having a number of columns, the number of columns of the second mapping matrix corresponding to the number of symbols of each TRN subfield.
2. The method of claim 1 , wherein the number of spatial streams is four, and the first mapping matrix is
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3. The method of claim 1 , wherein the number of spatial streams is eight, and the first mapping matrix is
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4. The method of claim 1 , wherein the number of symbols for a TRN subfield is four, and the second mapping matrix is
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5. The method of claim 1 , wherein the number of symbols for a TRN subfield is eight, the second mapping matrix is:
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6. A device configured for transmitting a physical layer protocol data unit (PPDU) in a wireless local area network, the device comprising:
a radio frequency module configured to receive radio signals;
a processor operatively coupled with the radio frequency module; and
memory disposed to said processor, said memory comprising instructions that, when executed by said processor, causes the device to:
generate a PPDU including a first short training (ST) field, a first channel estimation (CE) field, a header field, a second ST field, a second CE field, a data field and a training (TRN) field; and
transmit the PPDU;
wherein the header field comprises a stream field indicating a number of spatial streams,
wherein the second CE field comprises a number of symbols, the number of symbols for the second CE field determined based on the number of spatial streams of the header field,
wherein the second CE field generated from a first mapping matrix, the first mapping matrix having a number of columns, the number of columns corresponding to the number of symbols for the second CE field,
wherein the TRN field comprises a plurality of TRN subfields, each TRN subfield comprising a number of symbols, each TRN subfield generated from a second mapping matrix having a number of columns, the number of columns of the second mapping matrix corresponding to the number of symbols of each TRN subfield.
7. The device of claim 6 , wherein the number of spatial streams is four, and the first mapping matrix is
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8. The device of claim 6 , wherein the number of spatial streams is eight, and the first mapping matrix is
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9. The device of claim 6 , wherein the number of symbols for a TRN subfield is four, and the second mapping matrix is
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10. The device of claim 6 , wherein the number of symbols for a TRN subfield is eight, and the second mapping matrix is
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