Method and apparatus for providing channel quality feedback in an orthogonal frequency division multiplexing communication system
In an Orthogonal Frequency Division Multiplexing communication system, a user equipment reports channel quality information that is sufficient to construct a fading profile of a frequency bandwidth and that does not consuming the overhead resulting from the reporting of CQI for every sub-band of the frequency bandwidth. In the communication system, the frequency bandwidth may be represented by multiple sub-band levels, wherein each sub-band level comprises a division of the frequency bandwidth into a number of sub-bands different from the number of sub-bands of the other sub-band levels. The user equipment measures a channel quality associated with each sub-band of a sub-band level of the multiple sub-band levels, selects a sub-band of the sub-band level based on the measured channel qualities, and reports channel quality information associated with the selected sub-band to a radio access network.
1. A method for providing channel quality feedback in an Orthogonal Frequency Division Multiplexing communication system, wherein a frequency bandwidth is represented by a plurality of sub-band levels, wherein each sub-band level comprises a division of the frequency bandwidth into a number of sub-bands different from the number of sub-bands of the other sub-band levels, and wherein the method comprises:
selecting a sub-band of a first sub-band level of the plurality of sub-band levels based on a predefined list of sub-bands to monitor;
measuring a channel quality associated with one or more sub-bands of a second sub-band level of the plurality of sub-band levels, wherein the selected sub-band of the first sub-band level is divided into a plurality of sub-bands to produce the sub-bands of the second sub-band level;
selecting a sub-band of the one or more sub-bands of the second sub-band level; and
reporting a channel quality information message for at least the selected sub-band of the second sub-band level to a radio access network, wherein the channel quality information message comprises channel quality information for each reported sub-band and an identifier of the selected sub-band of the second sub-band level.
2. The method of claim 1 , wherein the first sub-band level comprises a single sub-band.
3. A user equipment configured to report a channel quality in an Orthogonal Frequency Division Multiplexing communication system, wherein a frequency bandwidth is represented by a plurality of sub-band levels, wherein each sub-band level comprises a division of the frequency bandwidth into a number of sub-bands different from the number of sub-bands of the other sub-band levels and wherein the user equipment comprises:
a processor configured to select a sub-band of the first sub-band level based on a predefined list of sub-bands to monitor;
said processor to measure a channel quality associated with one or more sub-bands of a second sub-band level of the plurality of sub-band levels, wherein the selected sub-band of the first sub-band level is divided into a plurality of sub-bands to produce the sub-bands of the second sub-band level;
said processor to select a sub-band of the one or more measured sub-bands of the second sub-band level; and
said processor to report a channel quality information message associated with at least the selected sub-band of the second sub-band level to a radio access network, wherein the channel quality information message comprises channel quality information for each reported sub-band and an identifier of the selected sub-band of the second sub-band level.
4. The user equipment of claim 3 , wherein the first sub-band level comprises a single sub-band.