Selective Interference Rejection Combining

• US 20120115520A1
• Filed: 04/22/2009
• Published: 05/10/2012
• Est. Priority Date: 04/22/2009
• Status: Active Grant

• Current Assignee: Nokia Solutions and Networks US LLC (Nokia Corporation)
• Original Assignee: Nokia Solutions and Networks US LLC (Nokia Corporation)
• Inventors: Rössel, Sabine, Tiirola, Esa Tapani, Viering, Ingo, Vainikka, Markku Juha, Piiralnen, Olli Juhani, Luo, Ji Jun, Taskinen, Mikko Kalevi, Paul, Timothy, Forster, Josef, Ritterhoff, Carsten
• Granted Patent: US 8,798,654 B2
• Time in Patent Office: Days
• US Class Current: 455/501
• CPC Class Codes: H04B 7/0857 using maximum ratio combining techniques, e.g. signal-to- interference ratio [SIR], received signal strenght indication [RSS]
• CPC Class Codes: H04L 1/20 using signal quality detector

Abstract

It is provided a method, including deciding, based on a previously estimated interference value, whether a user equipment or a sounding reference signal or a channel of a received uplink signal is affected by a colored interference more than a first predefined threshold, wherein colored interference is an interference having a spatial and/or spectral predominance; and suppressing interference rejection combining on the uplink signal if none of the user equipment, the sounding reference signal, and the channel of the received uplink signal is affected more than the first predefined threshold.

Claims

1. A method, comprising

deciding, based on a previously estimated interference value, whether a user equipment or a sounding reference signal or a channel of a received uplink signal is affected by a colored interference more than a first predefined threshold, wherein colored interference is an interference having a spatial and/or spectral predominance;

and

suppressing interference rejection combining on the uplink signal if none of the user equipment, the sounding reference signal, and the channel of the received uplink signal is affected more than the first predefined threshold.

2. The method according to claim 1, further comprising

performing interference rejection combining for the uplink signal, if it is decided that at least one of the user equipment, the sounding reference signal, and the channel is affected by colored interference more than the first predefined threshold.

3. The method according to claim 1, wherein the uplink signal comprises more than one partial subband including a first partial subband, the method further comprising

splitting the uplink signal into an uplink signal of the first partial subband and at least one uplink signal of the remaining subband;

deciding, based on a previously estimated interference value of the first partial subband, whether or not the uplink signal of the first partial subband is affected by colored interference more than a second predefined threshold; and

wherein

the performing interference rejection combining for the uplink signal comprises suppressing interference rejection combining for the uplink signal of the first partial subband, if it is decided that the uplink signal of the first partial subband is not affected more than the second predefined threshold.

4. The method according to claim 3, wherein the uplink band comprises more than one subband, the method further comprising

selecting at least one of the subbands affected more than the first predefined threshold into a first selection, and/or selecting at least one of the subbands affected not more than the first predefined threshold into a second selection;

and

allocating at least one of the subbands of the first selection to the user equipment, the sounding reference signal, or the channel according to a first predefined criterion, and/or allocating at least one of the subbands of the second selection to the user equipment, the signal, or the channel according to a second predefined criterion.

5. The method according to claim 4, wherein the deciding is based on the allocating.

6. The method according to claim 4, further comprising

estimating a colored interference of the uplink signal or, of the uplink signal of the first partial subband;

and

updating the interference value of the subband or of the first partial subband based on the estimated colored interference.

7. The method according to claim 6, further comprising

averaging the estimated colored interference over at least one of time, different user equipments, different sounding reference signals, and different channels;

and wherein

the updating is based on the averaged estimated colored interference.

8. The method according to claim 1, wherein the uplink is an uplink of a single carrier frequency division multiplex access, and wherein performing interference rejection combining in the frequency domain for data and demodulation reference symbols of a pilot is performed with respect to a pre-coded transmit alphabet.

18. Computer program product embodied on a computer-readable medium, comprising program instructions which perform, when run on a computer, the execution of which results in operations of the method according to claim 1.

9. An apparatus, comprising

deciding means configured to decide, based on a previously estimated interference value, whether or not a user equipment or a sounding reference signal or a channel of an uplink signal is affected by a colored interference more than a first predefined threshold, wherein colored interference is an interference having a spatial and/or spectral predominance;

and

switching means configured to suppress subjecting the uplink signal to a treatment by an interference rejection combining means configured to perform interference rejection combining, if it is decided by the deciding means that none of the user equipment, the sounding reference signal, and the channel is affected more than the first predefined threshold.

10. The apparatus according to claim 9, further comprising

interference rejection combining means configured to perform interference rejection combining on the uplink signal;

wherein the switching means is further configured to subject the uplink signal to a treatment by the interference rejection combining means, if it is decided by the deciding means that at least one of the user equipment, the sounding reference signal, and the channel is affected more than the first predefined threshold.

11. The apparatus according to claim 9, wherein the uplink signal comprises more than one partial subband including a first partial subband, the apparatus further comprising

splitting means configured to split the uplink signal into an uplink signal of the first partial subband and at least one uplink signal of the remaining subband;

wherein

the decision means is further configured to decide, based on a previously estimated interference value of the first partial subband, whether or not the uplink signal of the first partial subband is affected by colored interference more than a second predefined threshold;

the switching means is further configured to suppress subjecting the uplink signal of the first partial subband to a treatment by the interference rejection combining means, if it is decided by the deciding means that the uplink signal of the first partial subband is not affected more than the second predefined threshold.

12. The apparatus according to claim 11, wherein the uplink band comprises more than one subband, the apparatus further comprising

selecting means configured to select at least one of the subbands affected more than the first predefined threshold into a first selection and/or to select at least one of the subbands affected not more than the first predefined threshold into a second selection;

and

allocating means configured to allocate at least one of the subbands of the first selection to the user equipment, the sounding reference signal, or the channel according to a first predefined criterion, and/or to allocate at least one of the subbands of the second selection to the user equipment, the sounding reference signal, or the channel according to a second predefined criterion.

13. The apparatus according to claim 12, wherein the deciding means is configured to decide based on the allocation of the allocating means.

14. The apparatus according to claim 12, further comprising

estimation means configured to estimate a colored interference of the uplink signal or, of the uplink signal of the first partial subband;

and

updating means configured to update the interference value of the subband or of the first partial subband based on the estimated colored interference.

15. The apparatus according to claim 14, further comprising

averaging means configured to average the estimated colored interference over at least one of a time, different user equipments, different signals, and different channels;

and wherein

the updating means is further configured to update the interference value of the subband or the first partial subband based on the averaged estimated colored interference.

16. The apparatus according to claim 9, further comprising

base station means configured to provide a base station functionality according to a radio access technology of the uplink.

17. An eNodeB of a long term evolution system comprising an apparatus according to claim 9.