Efficient frame retransmission in a wireless communication environment
View Patent ↗The present invention relates to a link control automatic repeat request (ARQ) operation in a wireless communication environment. When a terminal sends an original request for communication resources, the request includes not only payload size, but preferably quality of service parameters associated with the data to be transmitted. During uplink communications, the base station performs the link control based ARQ for lost or corrupt packets. When lost or corrupt packets are identified, a link control entity at the base station determines the appropriate retransmission parameters and contacts the uplink scheduler, if necessary, to obtain the corresponding communication resources for retransmission. The additional communication resources for retransmission are provided in a message, such as a negative acknowledgement message, which is sent to the mobile terminal to trigger retransmission of the lost or corrupted data.
1. A method of facilitating retransmission of frames in a wireless communication environment comprising:
a) receiving a plurality of frames from a terminal over a wireless medium;
b) determining at least one frame was lost or corrupted during transmission over the wireless medium from the terminal;
c) determining if additional communication resources are required for retransmission of the at least one packet, and if the additional communication resources are required:
i) obtaining a grant of the additional communication resources for retransmission of the at least one frame over the wireless medium; and
ii) transmitting a negative acknowledgement indicating the at least one frame was lost or corrupted and providing the grant of the additional communication resources to the mobile terminal over the wireless medium, such that the additional communication resources for retransmission of lost or corrupted frames are provided to the mobile terminal with the negative acknowledgement to trigger retransmission; and
d) if the additional communication resources are not required:
i) transmitting the negative acknowledgement indicating a frame was lost or corrupted without providing the grant of the additional communication resources to the mobile terminal in association with the negative acknowledgement.
2. The method of claim 1 wherein the grant of the additional communication resources is obtained by accessing an uplink scheduler to request and receive the grant of the additional communication resources.
3. The method of claim 1 further comprising transmitting an original grant of communication resources to the mobile terminal for transmission of the plurality of frames and the at least one frame.
4. The method of claim 3 further comprising obtaining the original grant of additional communication resources for transmission of the plurality of frames and the at least one frame.
5. The method of claim 4 further comprising receiving a transmission request for communication resources to transmit the plurality of frames and the at least one frame from the mobile terminal.
6. The method of claim 5 wherein the transmission request includes payload and Quality of Service parameters bearing on the communication resources required to transmit the plurality of frames and the at least one frame.
7. The method of claim 1 wherein each of the steps is implemented using a link control protocol.
8. The method of claim 7 wherein the link control protocol is a radio link protocol and the plurality of frames and the at least one frame are radio link protocol frames.
9. The method of claim 1 wherein the negative acknowledgement is provided as part of an automatic repeat request process facilitating retransmission of lost or corrupt frames.
10. A system for facilitating retransmission of frames in a wireless communication environment comprising:
a) wireless communication electronics facilitating communications with a mobile terminal over a wireless medium;
b) a control system associated with the wireless communication electronics and adapted to:
i) receive a plurality of frames from the mobile terminal over the wireless medium;
ii) determine at least one frame was lost or corrupted during transmission over the wireless medium from the mobile terminal;
iii) determine if additional communication resources are required for retransmission of the at least one frame, and if the additional communication resources are required:
A) obtain a grant of the additional communication resources for retransmission of the at least one frame over the wireless medium; and
B) transmit a negative acknowledgement indicating the at least one frame was lost or corrupted and providing the grant of the additional communication resources to the mobile terminal over the wireless medium, such that the additional communication resources for retransmission of lost or corrupted frames are provided to the mobile terminal with the negative acknowledgement to trigger retransmission; and
iv) if the additional communication resources are not required:
A) transmitting a negative acknowledgement indicating a frame was lost or corrupted without providing the grant of the additional communication resources to the mobile terminal in association with the negative acknowledgement.
11. The system of claim 10 further comprising an uplink scheduler and wherein the control system is adapted to access the uplink scheduler to obtain the grant of the additional communication resources.
12. The system of claim 10 wherein the control system is further adapted to transmit an original grant of communication resources to the mobile terminal for transmission of the plurality of frames and the at least one frame.
13. The system of claim 12 wherein the control system is further adapted to obtain the original grant of additional communication resources for transmission of the plurality of frames and the at least one frame.
14. The system of claim 13 wherein the control system is further adapted to receive a transmission request for communication resources to transmit the plurality of frames and the at least one frame from the mobile terminal.
15. The system of claim 14 wherein the transmission request includes payload and Quality of Service parameters bearing on the communication resources required to transmit the plurality of frames and the at least one frame.
16. The system of claim 10 wherein the control system provides a radio link protocol layer using a link control protocol.
17. The system of claim 16 wherein the link control protocol is a radio link protocol and the plurality of frames and the at least one frame are radio link protocol frames.
18. The system of claim 10 wherein the negative acknowledgement is provided as part of an automatic repeat request process facilitating retransmission of lost or corrupted frames.