Outer-loop scheduling design for communication systems with channel quality feedback mechanisms
AssigneeQUALCOMM Incorporated
InventorsYongbin Wei, Jack M. Holtzman, Gang Bao, Sandip Sarkar, David Puig-Oses
Life of this patent
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Abstract
Methods and apparatus are presented for dynamically adjusting parameters of an outer-loop algorithm, which is used to determine the feasibility of a transmission format. The parameters of the outer-loop algorithm are adjusted according to channel conditions. In one embodiment, an erasure-based approach is used to determine whether to incrementally increase or incrementally decrease a margin parameter in the outer-loop algorithm. Once one margin parameter is altered, other margin parameters can be adjusted accordingly.
Claims25
In a wireless communication system, an apparatus for transmitting a packet in a transmission format, comprising:
- a receiving subsystem for receiving channel quality information from a remote station;
- a scheduling element for inserting a data payload into a packet for transmission, wherein the scheduling element is configured to use a outer-loop algorithm to determine the feasibility of a transmission format for the packet and to alter the parameters of the outer-loop algorithm in accordance with the channel quality information;
- and
- a transmission subsystem for transmitting the packet to the remote station.
In a wireless communication system, a method for adapting a margin parameter of an outer-loop algorithm used to schedule packet transmissions, comprising:
- receiving channel quality information from a remote station;
- determining a channel variation rate from the channel quality information;
- determining whether to increase or decrease the margin parameter by a margin increment, wherein the margin increment is based on the channel variation rate;
- comparing the margin parameter to a second margin parameter;
- and
- altering the second margin parameter according to a set of selection rules.
An apparatus for formatting a packet into a transmission format, comprising:
- a memory element;
- and
- a processing element configured to execute a set of instructions on the memory element, the set of instructions for:
- determining a fading curve representative of a transmission channel on which the packet is to be sent to a remote station;
- determining a margin offset to the fading curve based on a feedback message from the remote station;
- and
- determining whether a transmission format incorporating the margin offset is feasible for formatting the packet.
A method for formatting a packet into a transmission format, comprising:
- determining a fading curve representative of a transmission channel on which the packet is to be sent to a remote station;
- determining a margin offset to the fading curve based on a feedback message from the remote station;
- and
- determining whether a transmission format incorporating the margin offset is feasible for formatting the packet;
- and
- if feasible, then formatting the packet according the transmission format incorporating the margin offset.
Dependencies are inferred from the claim text.