Efficient vector quantizer for FD-MIMO systems

1. A method of operating a user equipment (UE) for vector quantization of feedback components, the method comprising:

identifying a grouping method for grouping channel coefficients for vector quantization and identifying a vector quantization codebook for vector quantization of grouped vectors based on one or more control signals received from an eNode B (eNB);

computing channel coefficients based on at least one channel measurement;

grouping the computed channel coefficients according to the identified grouping method to form a set of vectors;

performing vector quantization of the vectors using the identified vector quantization codebook;

processing the quantized vectors into one or more feedback signals; and

transmitting the one or more feedback signals to the eNB.

2. The method of claim 1 , wherein identifying the grouping method and the vector quantization codebook for grouping channel coefficients into vectors and for vector quantization of grouped vectors, respectively, comprise identifying, from the one or more control signals, an indication of a selected grouping method from a predetermined set of grouping methods and a selected vector quantization codebook from a predetermined set of vector quantization codebooks.

3. The method of claim 1 , further comprising:

estimating at least one profile of the channel coefficients based on the at least one channel measurement,

wherein transmitting the one or more feedback signals to the eNB comprises transmitting feedback associated with the at least one estimated profile for the eNB to determine quantization parameters for vector quantization of channel coefficients by the UE.

4. The method of claim 3 , wherein the quantization parameters include a selection of at least one grouping method from a set of grouping methods and at least one vector quantization codebook from a set of vector quantization codebooks.

5. The method of claim 1 , wherein performing the vector quantization of the vectors using the vector quantization codebook comprises using at least two different types of vector quantization for quantization of the channel coefficients based on different levels of correlations within a channel.

6. A method of operating an eNode B (eNB) for processing of vector quantized feedback, the method comprising:

transmitting, to a user equipment (UE), one or more control signals indicating a grouping method for grouping channel coefficients for vector quantization and a vector quantization codebook for vector quantization of grouped vectors;

receiving one or more feedback signals from the UE;

performing reconstruction of quantized channel coefficients identified from the one or more feedback signals using the indicated vector quantization codebook, wherein the channel coefficients based on at least one channel measurement; and

ungrouping the reconstructed channel coefficients based on the indicated grouping method.

7. The method of claim 6 , further comprising:

estimating at least one profile of the quantized channel coefficients identified from the one or more feedback signals;

selecting the grouping method for grouping of channel coefficients for vector quantization of feedback by the UE from a predetermined set of grouping methods based on the at least one estimated profile; and

selecting the vector quantization codebook for vector quantization of grouped vectors by the UE from a predetermined set of vector quantization codebooks based on the at least one estimated profile.

8. The method of claim 6 , further comprising:

measuring a distribution of the quantized channel coefficients;

determining quantization parameters for vector quantization of grouped channel coefficients feedback by the UE; and

sending, to the UE, at least one control signal indicating the quantization parameters for vector quantization of grouped channel coefficients for the UE feedback.

9. The method of claim 8 , wherein the quantization parameters include a selection of at least one grouping method from a set of grouping methods and at least one vector quantization codebook from a set of vector quantization codebooks.

10. An apparatus of a user equipment (UE) for vector quantization of feedback components, the apparatus comprising:

at least one processor configured to:

identify a grouping method for grouping channel coefficients for vector quantization and identify a vector quantization codebook for vector quantization of grouped vectors based on one or more control signals received from an eNode B (eNB),

compute channel coefficients based on at least one channel measurement,

group the computed channel coefficients according to the identified grouping method to form a set of vectors,

perform vector quantization of the vectors using the identified vector quantization codebook, and

process the quantized vectors into one or more feedback signals; and

a transceiver configured to transmit the one or more feedback signals to the eNB.

11. The apparatus of claim 10 , wherein the at least one processor is configured to identify, from the one or more control signals, an indication of a selected grouping method from a predetermined set of grouping methods and a selected vector quantization codebook from a predetermined set of vector quantization codebooks.

12. The apparatus of claim 10 , wherein:

the at least one processor is further configured estimate at least one profile of the channel coefficients based on the at least one channel measurement, and

the transceiver is configured to transmit feedback associated with the at least one estimated profile for the eNB to determine quantization parameters for vector quantization of channel coefficients by the UE.

13. The apparatus of claim 12 , wherein the quantization parameters include a selection of at least one grouping method from a set of grouping methods and at least one vector quantization codebook from a set of vector quantization codebooks.

14. The apparatus of claim 10 , wherein the at least one processor is configured to perform the vector quantization of the vectors using at least two different types of vector quantization for quantization of the channel coefficients based on different levels of correlations within a channel.

15. An apparatus of an eNode B (eNB) for processing of vector quantized feedback, the apparatus comprising:

a transceiver configured to:

transmit, to a user equipment (UE), one or more control signals indicating a grouping method for grouping channel coefficients for vector quantization and a vector quantization codebook for vector quantization of grouped vectors;

receive one or more feedback signals from the UE; and

at least one processor configured to:

perform reconstruction of quantized channel coefficients identified from the one or more feedback signals using the indicated vector quantization codebook, wherein the channel coefficients based on at least one channel measurement, and

ungroup the reconstructed channel coefficients based on the indicated grouping method.

16. The apparatus of claim 15 , wherein:

the at least one processor is further configured to:

estimate at least one profile of the quantized channel coefficients identified from the one or more feedback signals;

select the vector quantization codebook for vector quantization of grouped vectors by the UE from a predetermined set of vector quantization codebooks based on the at least one estimated profile; and

select the grouping method for grouping of channel coefficients for vector quantization of feedback by the UE from a predetermined set of grouping methods based on the at least one estimated profile.

17. The apparatus of claim 15 , wherein:

the at least one processor is further configured to measure a distribution of the quantized channel coefficients and determine quantization parameters for vector quantization of grouped channel coefficients feedback by the UE, and

the transceiver is further configured to send, to the UE, at least one control signal indicating the quantization parameters for vector quantization of grouped channel coefficients for the UE feedback.

18. The apparatus of claim 17 , wherein the quantization parameters include a selection of at least one grouping method from a set of grouping methods and at least one vector quantization codebook from a set of vector quantization codebooks.

19. The apparatus of claim 15 , wherein the transceiver is further configured to signal, to the UE, information indicating for the UE to use at least two different types of vector quantization for quantization of the channel coefficients fed back by the UE based on different levels of correlations within a channel.

20. The method of claim 1 , wherein the channel coefficients indicate measurements of a channel between the eNB and the UE.