Frame aggregation format
View Patent ↗A frame format for frame aggregation into a physical-layer packet employs an aggregated frame descriptor appended to one or more sub-frames. Each sub-frame comprises a header comprising logical-layer and sub-frame protocol information, optional verification information to verify the sub-frame data, and aggregated user data. The aggregated frame descriptor includes information identifying the packet as conforming to an aggregated frame format, and sub-frame descriptors identifying at least one of a position, a length, and a data rate of a corresponding sub-frame. The aggregated frame is then formed into a physical layer packet for transmission through a medium.
1. A receiving device-implemented method of generating an aggregate frame for a plurality of sub-frames, each sub-frame containing user data, the method comprising the steps of:
(a) the receiving device forming an aggregate data unit (ADU) from two or more sub-frames; and
(b) the receiving device generating an aggregate frame comprising:
(1) an aggregate frame descriptor including (i) an aggregate frame header indicating a type of frame, (ii) a value representing the number of sub-frames of the ADU, and (iii) a sub-frame descriptor including, for each of the two or more sub-frames, an address of a receiving device for the corresponding sub-frame; and
(2) the ADU,
wherein the addresses of receiving devices for the two or more sub-frames in the ADU are positioned, in the aggregate frame, before the ADU comprising the two or more sub-frames.
2. The invention as recited in claim 1 , further comprising the step of the receiving device adding an aggregate error control field to the ADU, the aggregate error control field having error detection/correction information for the aggregate frame.
3. The invention as recited in claim 2 , wherein the added aggregate error control field is a frame checksum.
4. The invention as recited in claim 1 , further comprising the step of the receiving device generating a physical layer packet from the aggregate frame.
5. The invention as recited in claim 4 , further comprising the step of the receiving device transmitting the physical layer packet through a medium.
6. The invention as recited in claim 4 , wherein the step of generating the physical layer packet comprises the step of adding a preamble and a physical layer header.
7. The invention as recited in claim 1 , wherein step (a) further comprises the step of ordering the position of each of the sub-frames in the ADU based on a data rate of the sub-frame.
8. The invention as recited in claim 1 , wherein, for step (a), the position of each of the sub-frames in the ADU is ordered based on differing data rates of the sub-frames.
9. The invention as recited in claim 1 , wherein, for step (a), the position of each of the sub-frames in the ADU is ordered based on increasing data rate.
10. The invention as recited in claim 1 , wherein, for step (a), each sub-frame comprises a sub-frame header and sub-frame data.
11. The invention as recited in claim 10 , wherein, for step (a), each sub-frame further comprises a sub-frame error control field having error detection/correction information for the sub-frame.
12. The invention as recited in claim 1 , wherein, for step (b), the aggregate frame header comprises a frame control field indicating the type of frame is an aggregate frame.
13. The invention as recited in claim 12 , wherein, for step (b), the aggregate frame descriptor further comprises an error control field having error detection/correction information for the aggregate frame descriptor.
14. The invention as recited in claim 1 , wherein, for step (b), each sub-frame descriptor comprises an address corresponding to a receiving device for the associated sub-frame, and position information identifying a position of the associated sub-frame within the aggregate frame.
15. The invention as recited in claim 14 , wherein, for step (b), each sub-frame descriptor comprises an error control field having error detection/correction information for the corresponding sub-frame.
16. The invention as recited in claim 1 , wherein the receiving device includes a processor of an integrated circuit (IC), the processor adapted to perform the method steps.
17. The invention as recited in claim 16 , wherein the IC is embodied in a device operating in accordance with an IEEE 802.11 standard for wireless local area networks.
18. Apparatus for generating an aggregate frame for a plurality of sub-frames, the apparatus comprising:
a first circuit adapted to form an aggregate data unit (ADU) from two or more sub-frames; and
a second circuit adapted to generate an aggregate frame comprising:
(1) an aggregate frame descriptor including (i) an aggregate frame header indicating a type of frame, (ii) a value representing the number of sub-frames of the ADU, and (iii) a sub-frame descriptor including, for each of the two or more sub-frames, an address of a receiving device for the corresponding sub-frame; and
(2) the ADU,
wherein the addresses of receiving devices for the two or more sub-frames in the ADU are positioned, in the aggregate frame, before the ADU comprising the two or more sub-frames.
19. A method of processing a packet by a receiving device, the method comprising the steps of:
(a) the receiving device receiving a frame type of the packet;
(b) the receiving device receiving, if the frame type is an aggregate frame, one or more descriptors corresponding to two or more sub-frames of the packet, the one or more descriptors including, for each of the two or more sub-frames, an address of a receiving device for the corresponding sub-frame;
(c) the receiving device determining, for each descriptor, whether the corresponding sub-frame is for the receiving device; and
(d) the receiving device extracting, for each sub-frame determined to be for the receiving device, a corresponding data frame,
wherein the addresses of receiving devices for the two or more sub-frames in the packet are positioned, in the aggregate frame, before the packet comprising the two or more sub-frames.
20. The invention as recited in claim 19 , further comprising the step of the receiving device verifying, for each sub-frame determined to be for the receiving device, error detection/correction information corresponding to the sub-frame.
21. The invention as recited in claim 20 , further comprising the step of the receiving device correcting one or more errors based on the error detection/correction information.
22. The invention as recited in claim 19 , wherein step (d) comprises the step of detecting the position and length of the sub-frame in the packet.
23. The invention as recited in claim 19 , wherein the receiving device includes a processor of an integrated circuit (IC), the processor adapted to perform the method steps.
24. The invention as recited in claim 23 , wherein the IC is embodied in a device operating in accordance with an IEEE 802.11 standard for wireless local area networks.
25. A receiving device for processing a packet comprising:
a first circuit adapted to receive, if a frame type of the packet is an aggregate frame, one or more descriptors corresponding to two or more sub-frames of the packet, the one or more descriptors including, for each of the two or more sub-frames, an address of a receiving device for the corresponding sub-frame; and
a second circuit adapted to i) determine, for each descriptor, whether the corresponding sub-frame is for the receiving device and ii) extract, for each sub-frame determined to be for the receiving device, a corresponding data frame,
wherein the addresses of receiving devices for the two or more sub-frames in the packet are positioned, in the aggregate frame, before the packet comprising the two or more sub-frames.
26. A computer-readable storage medium having stored thereon a plurality of instructions, the plurality of instructions including instructions which, when executed by a processor, cause the processor to implement a method for generating an aggregate frame for a plurality of sub-frames, each sub-frame containing user data, the method comprising the steps of:
(a) forming an aggregate data unit (ADU) from two or more sub-frames; and
(b) generating an aggregate frame comprising:
(1) an aggregate frame descriptor including (i) an aggregate frame header indicating a type of frame, (ii) a value representing the number of sub-frames of the ADU, and (iii) a sub-frame descriptor including, for each of the two or more sub-frames, an address of a receiving device for the corresponding sub-frame; and
(2) the ADU,
wherein the addresses of receiving devices for the two or more sub-frames in the ADU are positioned, in the aggregate frame, before the ADU comprising the two or more sub-frames.
27. A computer-readable storage medium having stored thereon a plurality of instructions, the plurality of instructions including instructions which, when executed by a processor, cause the processor to implement a method for generating an aggregate frame for a plurality of sub-frames, the method comprising the steps of:
(a) receiving a frame type of the packet;
(b) receiving, if the frame type is an aggregate frame, one or more descriptors corresponding to two or more sub-frames of the packet, the one or more descriptors including, for each of the two or more sub-frames, an address of a receiving device for the corresponding sub-frame;
(c) determining, for each descriptor, whether the corresponding sub-frame is for the receiving device; and
(d) extracting, for each sub-frame determined to be for the receiving device, a corresponding data frame,
wherein the addresses of receiving devices for the two or more sub-frames in the packet are positioned, in the aggregate frame, before the packet comprising the two or more sub-frames.