Assistance information for advanced receivers

Patent metadata

Field	Value
Publication number	US-9531459-B2
Application number	US-201514674989-A
Country	US
Kind code	B2
Filing date	Mar 31, 2015
Priority date	May 9, 2014
Publication date	Dec 27, 2016
Grant date	Dec 27, 2016

Abstract

Systems and methods relating to assisting a wireless device with suppression of an interfering physical channel during reception of a desired physical channel are disclosed. In some embodiments, a method of operation of a wireless device to assist with suppression of an interfering physical channel during reception of a desired physical channel comprises receiving assistance information for an interfering physical channel and receiving a desired physical channel while suppressing the interfering physical channel according to the assistance information for the interfering physical channel. The assistance information comprises an identity used to generate a reference signal associated with the interfering physical channel and information indicative of one or more transmission constraints on transmission of the interfering physical channel, the one or more transmission constraints comprising a spatial multiplexing rank restriction and/or a precoding matrix restriction.

First claim

What is claimed is:

1. A method of operation of a wireless device to assist with suppression of an interfering physical channel during reception of a desired physical channel, comprising:
receiving assistance information for an interfering physical channel, the assistance information comprising:
an identity used to generate a reference signal associated with the interfering physical channel; and
information indicative of one or more transmission constraints on transmission of the interfering physical channel, the one or more transmission constraints comprising at least one of a group consisting of:

a spatial multiplexing rank restriction and a precoding matrix restriction; and
receiving a desired physical channel while suppressing the interfering physical channel according to the assistance information for the interfering physical channel.

2. The method of claim 1 wherein the one or more transmission constraints comprise the spatial multiplexing rank restriction.

3. The method of claim 2 wherein the spatial multiplexing rank restriction defines a number of spatial multiplexing layers that the wireless device can assume are, at most, present on the interfering physical channel, where the number of spatial multiplexing layers defined by the spatial multiplexing rank restriction is less than a maximum number of spatial multiplexing layers that could be used to transmit the interfering physical channel.

4. The method of claim 2 further comprising providing an indication of a capability to receive a physical channel in the presence of interference from physical channels and to process indications of interfering physical channel constraints.

5. The method of claim 4 wherein the indication of a capability to receive a physical channel in the presence of interference from physical channels and to process indications of interfering physical channel constraints comprises a subset of interfering transmission modes.

6. The method of claim 1 wherein the one or more transmission constraints comprise the precoding matrix restriction.

7. The method of claim 6 wherein the precoding matrix restriction defines a subset of a set of precoding matrices, and:
the set of precoding matrices comprises all precoding matrices that could be used to transmit the interfering physical channel;
the subset of the set of precoding matrices being less than all precoding matrices in the set of precoding matrices; and
the subset of the set of precoding matrices defining precoding matrices that the wireless device can assume are the only precoding matrices that can be used for transmission of the interfering physical channel.

8. The method of claim 1 wherein the one or more transmission constraints comprise the spatial multiplexing rank restriction and the precoding matrix restriction.

9. The method of claim 1 wherein the one or more transmission constraints further comprise a transmission mode constraint.

10. The method of claim 1 wherein the identity is a physical cell identity.

11. The method of claim 1 wherein the identity is a scrambling identity.

12. The method of claim 1 wherein the interfering physical channel is an interfering Long Term Evolution, LTE, Physical Downlink Shared Channel, PDSCH, and the desired physical channel is a desired PDSCH.

13. The method of claim 12 wherein receiving assistance information comprises receiving the assistance information via Radio Resource Control, RRC, signaling.

14. The method of claim 12 wherein the one or more transmission constraints comprise the spatial multiplexing rank restriction and the precoding matrix restriction, and receiving the desired physical channel while suppressing the interfering physical channel according to the assistance information for the interfering physical channel, comprises:
forming a channel estimate of one or more interfering Common Reference Signal, CRS, ports using a physical cell identity that corresponds to the identity of the interfering PDSCH;
detecting a Precoding Matrix Indicator, PMI, and a spatial multiplexing rank of the interfering PDSCH using the precoding matrix restriction, the spatial multiplexing rank restriction, and the channel estimate; and
receiving the desired PDSCH while suppressing the interfering PDSCH according to the PMI and the spatial multiplexing rank of the interfering PDSCH detected using the precoding matrix restriction, the spatial multiplexing rank restriction, and the channel estimate.

15. The method of claim 14 wherein the one or more transmission constraints further comprise a transmission mode constraint associated with the identity, and the method further comprises:
determining whether one or more transmission modes that can be used for transmission of the interfering physical channel as indicated by the transmission mode constraint can use PMI feedback;
wherein forming the channel estimate, detecting at least one of the PMI and the spatial multiplexing rank of the interfering PDSCH, and receiving the desired PDSCH while suppressing the interfering PDSCH are performed upon determining that the one or more transmission modes associated with the identity can use PMI feedback.

16. The method of claim 12 wherein the one or more transmission constraints comprise a spatial multiplexing rank restriction, and receiving the desired physical channel while suppressing the interfering physical channel according to the assistance information for the interfering physical channel, comprises:
forming a channel estimate using a scrambling identity of one or more interfering Demodulation Reference Signal, DMRS, ports, where the scrambling identity corresponds to the identity used to generate DMRS associated with the interfering PDSCH;
detecting a spatial multiplexing rank of the interfering PDSCH using the spatial multiplexing rank restriction and the channel estimate; and
receiving the desired PDSCH while suppressing the interfering PDSCH according to the spatial multiplexing rank of the interfering PDSCH detected using the spatial multiplexing rank restriction and the channel estimate.

17. The method of claim 1 wherein the interfering physical channel is assumed by the wireless device to be quasi-collocated at least with respect to Doppler shift and Doppler spread with the desired physical channel.

18. A wireless device assisted to suppress an interfering physical channel during reception of a desired physical channel, comprising:
a transceiver module;
a processing module; and
a memory module storing software executable by the processing module whereby the wireless device is operative to:
receive assistance information for an interfering physical channel, the assistance information comprising:
an identity used to generate a reference signal associated with the interfering physical channel; and
information indicative of one or more transmission constraints on transmission of the interfering physical channel, the one or more transmission constraints comprising at least one of a group consisting of: a spatial multiplexing rank restriction and a precoding matrix restriction; and

receive a desired physical channel while suppressing the interfering physical channel according to the assistance information for the interfering physical channel.

19. A method of operation of a radio access node to assist with suppression of an interfering physical channel during reception of a desired physical channel at a wireless device, comprising:
transmitting assistance information to the wireless device for an interfering physical channel, the assistance

Assignees

• Ericsson Telefon Ab L M

Inventors

• Harrison Mark
• Jöngren George
• Lincoln Bo
• Lindbom Lars
• Muruganathan Siva
• Sesia Stefania

Classifications

• H04B7/0487

  Codebooks having a nested structure · CPC title

• H04B7/0473 Primary

  taking constraints in layer or codeword to antenna mapping into account · CPC title

• H04B7/0456 Primary

  Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting · CPC title

• H04B7/0486

  taking channel rank into account · CPC title

• H04L5/0048

  Allocation of pilot signals, i.e. of signals known to the receiver (allocation of control signalling H04L5/0053; use of control signalling H04L5/0091) · CPC title