Channel quality indicator for time, frequency and spatial channel in terrestrial radio access network

• US 20070026810A1
• Filed: 08/01/2005
• Published: 02/01/2007
• Est. Priority Date: 08/01/2005
• Status: Active Grant

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Inventors: Nory, Ravikiran, Sun, Yakun, Classon, Brian, Love, Robert, Stewart, Kenneth, Bachu, Raja
• Granted Patent: US 9,184,898 B2
• Time in Patent Office: Days
• US Class Current: 455/67.110
• CPC Class Codes: H04B 7/063 Parameters other than those covered in groups H04B7/0623 - H04B7/0634, e.g. channel matrix rank or transmit mode selection
• CPC Class Codes: H04B 7/0632 Channel quality parameters, e.g. channel quality indicator [CQI]
• CPC Class Codes: H04B 7/066 Combined feedback for a number of channels, e.g. over several subcarriers like in orthogonal frequency division multiplexing [OFDM]
• CPC Class Codes: H04B 7/0697 using spatial multiplexing
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0046 Determination of how many bits are transmitted on different sub-channels
• CPC Class Codes: H04L 5/0057 Physical resource allocation for CQI
• CPC Class Codes: H04L 5/0091 Signaling for the administration of the divided path
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports
• CPC Class Codes: H04W 72/54 based on quality criteria

Abstract

A wireless communication terminal that communicates on a plurality of sub-carriers divided into a plurality of frequency bands, wherein each frequency band includes at least one sub-carrier. The terminal measures (310) a channel quality indicator (CQI) for a plurality of frequency bands, identifies (320) a subset of frequency bands for which the channel quality indicator has been measured based on a subset criterion, and transmits (330) a report identifying a subset of frequency bands for which a channel quality indicator has been measured or frequency bands not in the subset. In some embodiments, the report also includes a subset CQI value associated with at least the subset of frequency bands.

Claims

1. A method in a wireless communication device capable of communicating on a channel comprising a plurality of sub-carriers divided into a plurality of frequency bands, wherein each frequency band includes at least one sub-carrier, the method comprising:

measuring a channel quality indicator for a plurality of frequency bands;

identifying a subset of frequency bands for which the channel quality indicator has been measured based on a subset criterion;

sending information identifying at least one of the subset of frequency bands for which the channel quality indicator has been measured or frequency bands not in the subset of frequency bands for which the channel quality indicator has been measured, and sending a subset channel quality indicator value associated with at least the subset of frequency bands.

2. The method of claim 1, sending information includes sending a bit map identifying the subset of frequency bands for which the channel quality indicator has been measured, the bit map having at least one bit location for each of the plurality of frequency bands for which a channel quality indicator was measured.

3. The method of claim 1, further comprising receiving information identifying the plurality of frequency bands for which the channel quality indicator is to be measured before measuring.

4. The method of claim 1, reporting the plurality of frequency bands for which the channel quality indicator was measured.

5. The method of claim 1, sending a function of the channel quality indicator measured for the subset of frequency bands.

6. The method of claim 5, sending the function of the channel quality indicator measured includes sending at least one of an average of the channel quality indicators measured for the subset of frequency bands, a minimum channel quality indicator measured for the subset of frequency bands, a median channel quality indicator measured for the subset of frequency bands, or a maximum channel quality indictor measured for the subset of frequency bands.

7. The method of claim 1, identifying the subset of frequency bands for which the channel quality indicator has been measured based on a subset criterion includes

identifying at least one frequency band based on a reference channel quality indicator, and

identifying additional frequency bands having a measured channel quality indicator within a distance of the reference channel quality indicator of the at least one frequency band.

8. The method of claim 2, sending at least one additional bit with the bit map, the additional bit indicative of a channel quality indicator measured for at least one frequency band that is not in the subset of frequency bands.

9. The method of claim 2,

sending at least one additional bit with the bit map, the at least one additional bit indicative of a channel quality indicator measured for first and second frequency bands that are not in the subset of frequency bands,

the first and second frequency bands located on adjacent sides of or displaced a predetermined distance from at least one of the frequency bands in the subset of frequency bands.

10. The method of claim 2,

sending a plurality of additional bits with the bit map, the plurality of additional bits corresponding in number to a number of frequency bands in the subset of frequency bands,

each of the plurality of additional bits indicative of a channel quality indicator for at least one frequency band adjacent to the frequency band to which the additional bit corresponds,

the at least one frequency band adjacent to the frequency band to which the additional bit corresponds not in the subset of frequency bands.

11. The method of claim 1, identifying the subset of frequency bands wherein the maximum size of the subset is less than a number corresponding to the plurality of frequency bands.

12. The method of claim 1, identifying the subset of frequency bands wherein the subset criterion is based traffic type or data service supported by a network in which the wireless communication device operates.

13. The method of claim 1,

the wireless communication device capable of communicating on first and second channels each comprising a plurality of sub-carriers divided into a plurality of frequency bands, wherein each frequency band includes at least one sub-carrier,

measuring a channel quality indicator for a plurality of frequency bands on the first and second channels;

identifying subsets of frequency bands for which the channel quality indicator has been measured on the first and second channels based on a subset criterion;

alternately sending information identifying at least one of the subset of frequency bands for which the channel quality indicator has been measured on the first and second channel or frequency bands not in the subset of frequency bands for which the channel quality indicator has been measured on the first and second channels, and alternately sending a subset channel quality indicator value associated with at least the subset of frequency bands identified on the first and second channels.

14. The method of claim 1,

identifying the subset of frequency bands for which the channel quality indicator has been measured based on a subset criterion that is based at least partly on Doppler frequency.

15. The method of claim 1, receiving a partial control assignment, constructing a full control assignment from the partial control assignment and the frequency band channel quality indicator measurement information.

16. A wireless communication terminal, comprising:

a transceiver capable of communicating on a channel comprising a plurality of sub-carriers divided into a plurality of frequency bands, wherein each frequency band includes at least one sub-carrier;

a processor communicably coupled to the transceiver, the processor measuring a channel quality indicator for a plurality of frequency bands, and for identifying a subset of frequency bands for which the channel quality indicator has been measured based on a subset criterion,

the processor generating information for transmission by the transceiver,

the generated information identifying at least one of a subset of frequency bands for which a channel quality indicator has been measured or frequency bands not in the subset of frequency bands for which a channel quality indicator has been measured, the generated information also including a subset channel quality indicator value associated with at least the subset of frequency bands.

17. The terminal of claim 16, the generated information is in the form of a bit map.

18. The terminal of claim 17, the bit map includes at least one bit indicative of a channel quality indicator measured for at least one frequency band that is not in the subset of frequency bands.

19. The terminal of claim 16, the subset channel quality indicator value includes at least one of an average of the channel quality indicators measured for the subset of frequency bands, a minimum channel quality indicator measured for the subset of frequency bands, a median channel quality indicator measured for the subset of frequency bands, or a maximum channel quality indictor measured for the subset of frequency bands.

20. The terminal of claim 16,

identifying additional frequency bands having a measured channel quality indicator within a distance of the reference channel quality indicator of the at least one frequency band.

21. The terminal of claim 17,

the bit map includes at least one additional bit indicative of a channel quality indicator measured for first and second frequency bands that are not in the subset of frequency bands,

the first and second frequency bands located on adjacent sides of or displaced a predetermined distance from at least one of the frequency bands in the subset of frequency bands.

22. A wireless communication terminal, comprising:

a transceiver capable of communicating on a channel comprising a plurality of sub-carriers divided into a plurality of frequency bands, wherein each frequency band includes at least one sub-carrier;

a processor communicably coupled to the transceiver, the processor measuring a channel quality indicator for a plurality of frequency bands, and for identifying a subset of frequency bands for which the channel quality indicator has been measured based on a subset criterion,

the processor generating information for transmission by the transceiver,

the generated information identifying a subset of frequency bands for which a channel quality indicator has been measured, the generated information also including a subset channel quality indicator value associated with at least the subset of frequency bands.