Method and base station for providing an estimate of interference and noise power of an uplink resource block

Patent metadata

Field	Value
Publication number	US-9426683-B2
Application number	US-201214398273-A
Country	US
Kind code	B2
Filing date	May 2, 2012
Priority date	May 2, 2012
Publication date	Aug 23, 2016
Grant date	Aug 23, 2016

Abstract

A method in a base station ( 110 ) for providing an estimate of interference and noise power of an uplink resource block. The base station ( 110 ) is comprised in a cellular communications network ( 100 ). The base station ( 110 ) receives ( 401, 901 ) on multiple antenna elements ( 112 a - c ) of a receiver antenna ( 112 ) a signal comprising interference and noise. The base station ( 110 ) calculates ( 402, 902 ) an interference and noise covariance matrix for the resource block based on the received signal. The base station ( 110 ) then calculates ( 903, 403 ) the estimate based on the calculated interference and noise covariance matrix, the number of the multiple antenna elements ( 112 a - c ) of the receiver antenna ( 112 ) and a channel covariance matrix for a virtual user equipment. The provided estimate enables an interference and noise measure when Interference Rejection Combining (!RC) is applied in the uplink. Thereby more efficient use of uplink Frequency Selective Scheduling (FSS) together with uplink IRC and improved performance in the cellular communications network is enabled.

First claim

The invention claimed is:

1. A method in a base station for providing an estimate of interference and noise power of an uplink resource block, the base station being comprised in a cellular communications network, wherein the method comprises:
receiving, on multiple antenna elements of a receiver antenna, a signal comprising interference and noise;
calculating an interference and noise covariance matrix for the resource block, based on the received signal; and
calculating the estimate based on the calculated interference and noise covariance matrix, the number of the multiple antenna elements of the receiver antenna, and a channel covariance matrix for a virtual user equipment, wherein the calculated estimate corresponds to:

I
IRC

=

N
A

Tr
⁡

(

H
^

⁢

⁢

Q

-
1

)

,

where N A is the number of the multiple antenna elements, Q −1 is the inverse of the calculated interference and noise covariance matrix, Ĥ is the channel covariance matrix for the virtual user equipment, and Tr is a matrix trace operation.

2. The method of claim 1 , wherein the channel covariance matrix for the virtual user equipment is an identity matrix.

3. The method of claim 1 , wherein the channel covariance matrix for the virtual user equipment has been determined statistically based on calculated channel covariance matrices for numerous real user equipments.

4. The method of claim 3 , wherein the channel covariance matrix for the virtual user equipment has been determined statistically by forming an average from the calculated channel covariance matrices for the numerous real user equipments.

5. The method of claim 3 , wherein the channel covariance matrices for the numerous real user equipments have been calculated for real user equipments presently being served by the base station and/or real user equipments that have been served previously by the base station.

6. The method of claim 1 , wherein the calculating is performed such that a respective estimate is provided for each one of a number of uplink resource blocks to be considered for assignment to one or more user equipments being served by the base station.

7. The method of claim 6 , wherein the method further comprises assigning uplink resource blocks to said one or more user equipments while taking into account the respectively provided estimate.

8. The method of claim 1 , wherein the base station is serving one or more user equipments comprised in the cellular communications network and the received signal comprises signal energy from said one or more user equipments in addition to the interference and noise.

9. A base station for providing an estimate of interference and noise power of an uplink resource block, the base station being comprised in a cellular communications network, wherein the base station comprises:
a receiver antenna, configured to receive, on multiple antenna elements thereof, a signal comprising interference and noise;
a first calculating circuitry, configured to calculate an interference and noise covariance matrix for the resource block based on the received signal; and
a second calculating circuitry, configured to calculate the estimate based on the calculated interference and noise covariance matrix, the number of the multiple antenna elements of the receiver antenna and a channel covariance matrix for a virtual user equipment, wherein the calculated estimate corresponds to:

I
IRC

=

N
A

Tr
⁡

(

H
^

⁢

⁢

Q

-
1

)

,

where N A is the number of antenna elements, Q −1 is the inverse of the calculated interference and noise covariance matrix, Ĥ is the channel covariance matrix for the virtual user equipment, and Tr is a matrix trace operation.

10. The base station of claim 9 , wherein the channel covariance matrix for the virtual user equipment is an identity matrix.

11. The base station of claim 9 , wherein the channel covariance matrix for the virtual user equipment has been determined statistically based on calculated channel covariance matrices for numerous real user equipments.

12. The base station of claim 11 , wherein the channel covariance matrix for the virtual user equipment has been determined statistically by forming an average from the calculated channel covariance matrices for the numerous real user equipments.

13. The base station of claim 11 , wherein the channel covariance matrices for the numerous real user equipments have been calculated for real user equipments presently being served by the base station and/or real user equipments that have been served previously by the base station.

14. The base station of claim 9 , wherein the first calculating circuitry and second calculating circuitry are further configured to provide a respective estimate for each one of a number of uplink resource blocks to be considered for assignment to one or more user equipments being served by the base station.

15. The base station of claim 14 , wherein the base station further comprises a resource assigning circuitry, configured to assign uplink resource blocks to said one or more user equipments while taking into account the respectively provided estimate.

16. The base station as claimed claim 9 , wherein the base station is further configured to serve one or more user equipments comprised in the cellular communications network and wherein the signal comprises signal energy from said one or more user equipments in addition to the interference and noise.

Assignees

• Sandberg David
• Åhlander Mats
• ERICSSON TELEFON AB L M (publ)

Inventors

• Sandberg David
• Åhlander Mats

Classifications

• H04W72/541

  using the level of interference · CPC title

• H04B17/345

  Interference values ({signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR]} H04B17/336) · CPC title

• H04W72/082

  Electricity · mapped topic

• H04L5/0094

  Indication of how sub-channels of the path are allocated · CPC title

• H04L5/0062

  Avoidance of ingress interference, e.g. ham radio channels · CPC title