Hybrid automatic repeat request techniques in a wireless local area network
A method performed by a first wireless station is described. The method includes determining, by a Media Access Control (MAC) layer of the first wireless station, a plurality of MAC Protocol Data Units (MPDUs) to transmit to a second wireless station in an aggregated MPDU, wherein a physical layer of the first station is to use a plurality of codewords to represent the plurality of MPDUs, wherein a first MPDU in the plurality of MPDUs is to be represented by a first set of codewords and a second MPDU is to be represented by a second set of codewords from the plurality of codewords; appending padding to the first MPDU such that the first set of codewords does not share a codeword with the second set of codewords; and transmitting the first set of codewords and the second set of codewords to the second wireless station.
1. A method performed by a first wireless station operating in a wireless network, the method comprising:
determining, by a Media Access Control (MAC) layer of the first wireless station, a plurality of MAC Protocol Data Units (MPDUs) to transmit to a second wireless station in an aggregated MPDU, wherein a Physical (PHY) layer of the first wireless station is to use a plurality of codewords to represent the plurality of MPDUs, wherein a first MPDU in the plurality of MPDUs is to be represented by a first set of codewords from the plurality of codewords and a second MPDU is to be represented by a second set of codewords from the plurality of codewords;
appending padding to the first MPDU such that the first set of codewords does not share a codeword with the second set of codewords, wherein the padding is information copied from a portion of one or more of the first MPDU and the second MPDU; and
transmitting the first set of codewords and the second set of codewords to the second wireless station.
2. The method of claim 1 , wherein the padding includes a transmitting device address of the first MPDU or a receiving device address of the first MPDU.
3. The method of claim 1 , wherein the padding is equal to one or more bits from the front of the first MPDU.
4. The method of claim 1 , wherein the padding includes Cyclic Redundancy Check (CRC) information for the first MPDU.
5. The method of claim 1 , wherein a preamble of the aggregated MPDU includes one or more of (1) an indication of a location of a first transmitting device address in the first set of codewords, which was present in the first MPDU, and (2) an indication of a location of a second transmitting device address in the second set of codewords, which was present in the second MPDU.
6. The method of claim 1 , wherein the plurality of MPDUs includes a quality of service null frame that indicates a transmitting device address for the first MPDU.
7. The method of claim 1 , further comprising:
determining to perform a Hybrid Automatic Repeat Request (HARQ) operation for the aggregated MPDU based on one of (1) a failure to receive an acknowledgement of the aggregated MPDU and (2) receipt of a negative acknowledgement for the aggregated MPDU; and
transmitting one or more of the first set of codewords and the second set of codewords to the second wireless station in response to determining to perform the HARQ operation.
8. The method of claim 7 , wherein the first wireless station determines to perform the HARQ operation in response to receiving an acknowledgement message from the second wireless station that includes a bitmap, and
wherein the bitmap includes a series of bits and each bit in the series of bits corresponds to whether a group of MPDUs in the plurality of MPDUs was successfully received and decoded by the second wireless station.
9. The method of claim 7 , wherein the determining to perform the HARQ operation is based on determining that one or more access categories of data in the aggregated MPDU are indicated to use the HARQ operation.
10. A first wireless device operating in a wireless network, the first wireless device comprising:
a memory device storing a set of instructions; and
a processor coupled to the memory device, wherein the set of instructions when executed by the processor cause the first wireless device to:
determine, by a Media Access Control (MAC) layer of the first wireless device, a plurality of MAC Protocol Data Units (MPDUs) to transmit to a second wireless device in an aggregated MPDU, wherein a Physical (PHY) layer of the first wireless device is to use a plurality of codewords to represent the plurality of MPDUs, wherein a first MPDU in the plurality of MPDUs is to be represented by a first set of codewords from the plurality of codewords and a second MPDU is to be represented by a second set of codewords from the plurality of codewords;
append padding to the first MPDU such that the first set of codewords does not share a codeword with the second set of codewords, wherein the padding is information copied from a portion of one or more of the first MPDU and the second MPDU; and
transmit the first set of codewords and the second set of codewords to the second wireless device.
11. The first wireless device of claim 10 , wherein the padding includes a transmitting device address of the first MPDU or a receiving device address of the first MPDU.
12. The first wireless device of claim 10 , wherein the padding is equal to one or more bits from the front of the first MPDU.
13. The first wireless device of claim 10 , wherein the padding includes Cyclic Redundancy Check (CRC) information for the first MPDU.
14. The first wireless device of claim 10 , wherein a preamble of the aggregated MPDU includes one or more of (1) an indication of a location of a first transmitting device address in the first set of codewords, which was present in the first MPDU, and (2) an indication of a location of a second transmitting device address in the second set of codewords, which was present in the second MPDU.
15. The first wireless device of claim 10 , wherein the plurality of MPDUs includes a quality of service null frame that indicates a transmitting device address for the first MPDU.
16. The first wireless device of claim 10 , wherein the set of instructions when executed by the processor further cause the first wireless device to:
determine to perform a Hybrid Automatic Repeat Request (HARQ) operation for the aggregated MPDU based on one of (1) a failure to receive an acknowledgement of the aggregated MPDU and (2) receipt of a negative acknowledgement for the aggregated MPDU; and
transmit one or more of the first set of codewords and the second set of codewords to the second wireless device in response to determining to perform the HARQ operation.
17. The first wireless device of claim 16 , wherein the first wireless device determines to perform the HARQ operation in response to receiving an acknowledgement message from the second wireless device that includes a bitmap, and
wherein the bitmap includes a series of bits and each bit in the series of bits corresponds to whether a group of MPDUs in the plurality of MPDUs was successfully received and decoded by the second wireless device.
18. The first wireless device of claim 16 , wherein the determining to perform the HARQ operation is based on determining that one or more access categories of data in the aggregated MPDU are indicated to use the HARQ operation.