Method and apparatus for multi-user frame aggregation

1. A method, comprising:

generating an aggregated physical layer (PHY) data unit for transmission of independent data for a plurality of stations via a communication channel, wherein the aggregated PHY data unit includes i) a plurality of individual PHY data units corresponding to the plurality of stations, ii) a midamble included in one of the plurality of individual PHY data units, and iii) information that indicates locations of at least some of the plurality of individual PHY data units within the aggregated PHY data unit, and wherein at least some of the information that indicates locations of at least some of the plurality of individual PHY data units is included in the midamble;

controlling beamforming while the aggregated PHY data unit is being transmitted, including:

i) causing transmission in an omnidirectional or quasi-omnidirectional manner while the information that indicates locations of at least some of the plurality of individual PHY data units is transmitting, and

ii) for each of the individual PHY data units, beamforming to the corresponding station while at least some of the corresponding individual PHY data unit is being transmitted.

2. The method according to claim 1 , wherein generating the aggregated PHY data unit comprises generating a preamble of the aggregated PHY data unit that includes some of the information that indicates locations of at least some of the plurality of individual PHY data units.

3. The method according to claim 2 , wherein controlling beamforming while the aggregated PHY data unit is being transmitted comprises: causing transmission in an omnidirectional or quasi-omnidirectional manner while a first portion of the preamble is transmitting; and beamforming to one of the stations in the plurality of stations while a second portion of the preamble is transmitting.

4. The method according to claim 3 , wherein the second portion of the preamble includes training fields associated with the one station.

5. The method according to claim 1 , wherein controlling beamforming while the aggregated PHY data unit is being transmitted comprises: causing transmission in an omnidirectional or quasi-omnidirectional manner while a first portion of the midamble is transmitting; and beamforming to one of the stations in the plurality of stations while a second portion of the midamble is transmitting.

6. The method according to claim 5 , wherein the second portion of the midamble includes training fields associated with the one station.

7. The method according to claim 1 , wherein controlling beamforming while the aggregated PHY data unit is being transmitted comprises:

causing transmission in an omnidirectional or quasi-omnidirectional manner while the midamble is transmitting; and

beamforming to one of the stations in the plurality of stations while a payload of the one individual PHY data unit is transmitting.

8. An apparatus, comprising:

a physical layer (PHY) processing unit to generate a PHY data unit for transmission of independent data for a plurality of stations via a communication channel, wherein the aggregated PHY data unit includes i) a plurality of individual PHY data units corresponding to the plurality of stations, ii) a midamble located in one of the plurality of individual PHY data units, and iii) information that indicates locations of at least some of the plurality of individual PHY data units within the aggregated PHY data unit, and wherein at least some of the information that indicates locations of at least some of the plurality of individual PHY data units is included in the midamble;

wherein the PHY processing unit includes a beamforming unit to:

i) cause transmission in an omnidirectional or quasi-omnidirectional manner while the information that indicates locations of at least some of the plurality of individual PHY data units is transmitting, and

ii) for each of the individual PHY data units, beamform to the corresponding station while at least some of the corresponding individual PHY data unit is being transmitted.

9. The apparatus according to claim 8 , wherein the PHY processing unit is configured to generate a preamble of the aggregated PHY data unit that includes some of the information that indicates locations of at least some of the plurality of individual PHY data units.

10. The apparatus according to claim 9 , wherein the beamforming unit is configured to:

cause transmission in an omnidirectional or quasi-omnidirectional manner while a first portion of the preamble is transmitting; and

beamform to one of the stations in the plurality of stations while a second portion of the preamble is transmitting.

11. The apparatus according to claim 10 , wherein the second portion of the preamble includes training fields associated with the one station.

12. The apparatus according to claim 8 , wherein the beamforming unit is configured to:

cause transmission in an omnidirectional or quasi-omnidirectional manner while a first portion of the midamble is transmitting; and

beamforming to one of the stations in the plurality of stations while a second portion of the midamble is transmitting.

13. The apparatus according to claim 12 , wherein the second portion of the midamble includes training fields associated with the one station.

14. The apparatus according to claim 8 , wherein the beamforming unit is configured to:

cause transmission in an omnidirectional or quasi-omnidirectional manner while the midamble is transmitting; and

beamform to one of the stations in the plurality of stations while a payload of the one individual PHY data unit is transmitting.