System and method for fast dynamic link adaptation
View Patent ↗The present invention discloses a method and system for enabling efficient reduction of TFCs in the TFCS to achieve desired transmission, while remaining within desired power and data requirements. Upon the UE transmission power requirement exceeding the maximum or allowable transmission power the MAC shall be informed for subsequent TFC selection of all TFCs that currently exceed this limit. The UE will then chose the TFC with the next lower transmission power requirement and the sequence will continue until an acceptable TFC is determined. The present invention also enables the replacement of the TFCs in the TFCS and advanced determination of non-supported TFCS. The TFCs that require transmission power greater then the maximum or allowed UE transmission power shall be determined continuously in every TTI, not just in TTIs where the maximum power has been exceeded.
1. A method for selecting a transport format combination (TFC) in wireless communication, the method comprising:
establishing a list of available TFCs, wherein the available TFCs are sorted according to a transmission power level required to transmit each available TFC;
selecting a TFC from the list of available TFCs;
determining whether a transmission power required to transmit the selected TFC exceeds a maximum allowed transmission power level;
determining whether a transmission power required to transmit the selected TFC exceeds a maximum allowed transmission power level for the remaining TFCs; and
updating the list of TFCs by eliminating TFCs which are determined to have a transmission power level exceeding the maximum allowed transmission power level.
2. The method of claim 1 further comprising selecting a TFC from the updated list of TFCs for transmission of a code composite transport channel (CCTrCH).
3. The method of claim 1 , wherein the list of available TFCs is updated periodically.
4. The method of claim 3 , wherein the list of available TFCs is updated in every transmit time interval (TTI).
5. The method of claim 1 further comprising:
determining whether a transmission power required to transmit a previously eliminated TFC still exceeds the maximum allowed transmission power level; and
updating the list of TFCs by restoring previously eliminated TFCs which are determined to have a transmission power level not exceeding the maximum allowed transmission power level.
6. The method of claim 1 wherein a TFC is selected from the list of available TFCs starting from a TFC having a highest transmission power level, whereby once a TFC which is determined not to exceed the maximum allowed transmission power level is identified, the remaining TFCs are automatically updated as available TFCs.
7. The method of claim 1 wherein TFCs are selected and updated by a media access control (MAC) entity and the determination whether a transmission power level for a TFC exceeds the maximum allowed transmission power level is made by a physical layer (PHY) entity.
8. The method of claim 1 wherein the list of available TFCs is updated using an index to each item of the sorted TFC list.
9. The method of claim 1 wherein the list of available TFCs is updated using a value indicating that a transmission power level of a TFC exceeds the maximum allowed transmission power level.
10. The method of claim 1 wherein the list of available TFCs is established upon establishment of a CCTrCH.
11. The method of claim 10 wherein each TFC is associated with a relative sensitivity, and a margin relative to the maximum allowed transmission power level is used in elimination of the TFC from the list of available TFCs.
12. A user equipment (UE) for selecting a transport format combination (TFC) in wireless communication, the UE comprising:
a TFC selection processor configured to select a TFC from a list of available TFCs, wherein the list is sorted according to a transmission power level required to transmit each available TFC and the TFC selection processor being further configured to update the list of available TFCs by eliminating all TFCs which are determined to have a transmission power level exceeding a maximum allowed transmission power level; and
a TFC processor for determining whether a transmission power required to transmit the selected TFC exceeds the maximum allowed transmission power level.
13. The UE of claim 12 , wherein a TFC is selected from the updated list of available TFCs for transmission of a CCTrCH.
14. The UE of claim 12 , wherein the list of available TFCs is updated periodically.
15. The UE of claim 14 wherein, the list of available TFCs is updated in every transmit time interval (TTI).
16. The UE of claim 12 , wherein the TFC processor further determines whether a transmission power required to transmit a previously eliminated TFC still exceeds the maximum allowed transmission power level, whereby the TFC selection processor restores previously eliminated TFCs which are determined to have a transmission power level not exceeding the maximum allowed transmission power level.
17. The UE of claim 12 , wherein a TFC is selected from the list of available TFCs starting from a TFC having a highest transmission power level, whereby once a TFC which is determined not to exceed the maximum allowed transmission power level is identified, the remaining TFCs are automatically updated as available TFCs.
18. The UE of claim 12 , wherein the TFC selection processor is included in a media access control (MAC) entity and the TFC processor is included in a physical layer (PHY) entity.
19. The UE of claim 12 , wherein the list of available TFCs is updated using an index to each item of the sorted TFC list.
20. The UE of claim 12 , wherein the list of available TFCs is updated using a value indicating that a transmission power level of a TFC exceeds the maximum allowed transmission power level.
21. The UE of claim 12 , wherein the list of available TFCs is established upon establishment of a CCTrCH.
22. The UE of claim 21 , wherein each TFC is associated with a relative sensitivity, and a margin relative to the maximum allowed transmit power level is used in elimination of the TFC from the list of available TFCs.