Wireless interference mitigation

• US 9,654,313 B2
• Filed: 12/03/2013
• Issued: 05/16/2017
• Est. Priority Date: 12/03/2012
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Intel Corporation
• Inventors: Han, Seunghee, Davydov, Alexei, Morozov, Gregory, Maltsev, Alexander, Sergeyev, Vadim
• Primary Examiner(s): PANWALKAR, VINEETA S
• Application Number:
  US14/440,335
• Publication Number:
  US 20150303958A1
• Time in Patent Office: 1,260 Days
• CPC Class Codes: H04B 1/12 Neutralising, balancing, or compensation arrangements
• CPC Class Codes: H04B 1/3827 Portable transceivers
• CPC Class Codes: H04B 17/24 with feedback of measurements to the transmitter
• CPC Class Codes: H04B 17/26 using historical data, averaging values or statistics
• CPC Class Codes: H04B 17/345 Interference values signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR] H04B17/336
• CPC Class Codes: H04B 7/0452 Multi-user MIMO systems
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04B 7/15557 Selecting relay station operation mode, e.g. between amplify and forward mode, decode and forward mode or FDD - and TDD mode
• CPC Class Codes: H04J 11/005 of intercell interference
• CPC Class Codes: H04J 11/0053 using co-ordinated multipoint transmission/reception co-ordinated antenna or beam-forming aspects H04B7/022
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0054 Maximum-likelihood or sequential decoding, e.g. Viterbi, Fano, ZJ algorithms
• CPC Class Codes: H04L 1/1854 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 1/1867 Arrangements specially adapted for the transmitter end
• CPC Class Codes: H04L 25/0202 Channel estimation
• CPC Class Codes: H04L 25/0204 of multiple channels
• CPC Class Codes: H04L 25/03305 Joint sequence estimation and interference removal joint detection of several desired signals H04L25/03331
• CPC Class Codes: H04L 27/0008 arrangements for allowing a transmitter or receiver to use more than one type of modulation negotiating modulation type for two-way transmission paths H04L5/1453
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0053 : Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04L 5/0055 : Physical resource allocation for ACK/NACK for physical mapping arrangements in ARQ protocols H04L1/1861
• CPC Class Codes: H04L 5/0057 : Physical resource allocation for CQI
• CPC Class Codes: H04L 5/0058 : Allocation criteria
• CPC Class Codes: H04L 5/0092 : Indication of how the channel is divided
• CPC Class Codes: H04W 24/02 : Arrangements for optimising operational condition
• CPC Class Codes: H04W 24/10 : Scheduling measurement reports ; Arrangements for measurement reports
• CPC Class Codes: H04W 36/10 : Reselecting an access point controller
• CPC Class Codes: H04W 40/16 : based on interference
• CPC Class Codes: H04W 52/0261 : managing power supply demand, e.g. depending on battery level
• CPC Class Codes: H04W 52/40 : during macro-diversity or soft handoff
• CPC Class Codes: H04W 72/12 : Wireless traffic scheduling
• CPC Class Codes: H04W 72/121 : for groups of terminals or users
• CPC Class Codes: H04W 72/20 : Control channels or signalling for resource management
• CPC Class Codes: H04W 72/23 : in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 72/51 : based on terminal or device properties
• CPC Class Codes: H04W 72/52 : based on load
• CPC Class Codes: H04W 72/54 : based on quality criteria
• CPC Class Codes: H04W 72/541 : using the level of interference
• CPC Class Codes: H04W 72/566 : of the information or information source or recipient
• CPC Class Codes: H04W 72/569 : of the traffic information
• CPC Class Codes: H04W 76/14 : Direct-mode setup
• CPC Class Codes: H04W 76/27 : Transitions between radio resource control [RRC] states
• CPC Class Codes: H04W 76/28 : Discontinuous transmission [DTX]; Discontinuous reception [DRX]
• CPC Class Codes: H04W 84/042 : Public Land Mobile systems, e.g. cellular systems
• CPC Class Codes: H04W 84/18 : Self-organising networks, e.g. ad-hoc networks or sensor networks
• CPC Class Codes: H04W 92/18 : between terminal devices
• CPC Class Codes: Y02D 30/70 : in wireless communication networks

Abstract

Embodiments relate to apparatus for wireless interference mitigation within a first User Equipment (UE). The apparatus comprises at least one channel estimator for estimating a first channel transfer function associated with a first received signal designated for the first UE, and for estimating a second channel transfer function associated with a second received, interference, signal. A symbol estimator is responsive to the at least one channel estimator to process at least the first received signal to produce a symbol estimation. A demodulator, which is responsive to the channel estimator, demodulates the symbol estimation to an output representing a received data unit corresponding to the symbol estimation. The demodulator has a processing unit arranged to demodulate the symbol estimation using the first channel transfer function, the second channel transfer function and a respective modulation scheme for at least the first received signal.

Claims

1. An apparatus for wireless interference mitigation within a first User Equipment (UE), the apparatus comprising:

at least one channel estimator to estimate a first channel transfer function associated with a first received signal designated for the first UE, and to estimate a second channel transfer function associated with a second received, interference, signal based on information provided to the apparatus from a network about a reference signal associated with the second received signal, wherein the reference signal is a UE-specific reference signal or a cell-specific reference signal;

at least one symbol estimator, responsive to the at least one channel estimator, to process at least the first received signal to produce a symbol estimation; and

a demodulator, responsive to the channel estimator, operable to demodulate the symbol estimation to produce an output representing a received data unit corresponding to the symbol estimation;

the demodulator comprising a processing unit arranged to demodulate the symbol estimation using the first channel transfer function and the second channel transfer function,

wherein the at least one symbol estimator comprises a symbol processor arranged to produce a set of signal candidates, ŝ

(t_i), defined as ŝ

(t_i)=slice{(h^hh)<sup>−

1</sup> h^h (r−

g·

t_i)}, where h is the channel transfer function on a given resource element for a serving channel, g is the channel transfer function on a given resource element for the serving channel, r is the received signal, t_i is an element of a set T of all possible interfering signal candidates, the superscript h represents a Hermitian transpose, and the superscript −

1 represents a matrix inverse.

2. The apparatus of claim 1, in which the processing unit is operable to calculate the received data unit using an estimation computation.

3. The apparatus of claim 2, in which the estimation computation is a Maximum Likelihood estimation computation.

4. The apparatus of claim 1, wherein the information provided to the apparatus from the network about the reference signal is provided in downlink control information.

5. The apparatus of claim 1, in which the reference signal comprises a UE-specific reference signal.

6. The apparatus of claim 4, in which the downlink control information is further associated with the first received signal.

7. The apparatus of claim 4, in which the downlink control information comprises a UE-specific reference signal parameter.

8. The apparatus of claim 7, in which the UE-specific reference signal (RS) parameter comprises a virtual cell identifier of UE-specific RS, a scrambling sequence index (nSCID), or UE-specific antenna ports.

9. The apparatus of claim 4, in which the downlink control information comprises a cell-specific reference signal (CRS) parameter.

10. The apparatus of claim 9, in which the CRS parameter comprises at least one of a physical cell identifier, number of CRS antenna ports, and a Multimedia Broadcast Single Frequency Network (MBSFN) subframe configuration.

11. The apparatus of claim 4, in which the downlink control information comprises at least one physical downlink shared channel (PDSCH) resource element mapping parameter.

12. The apparatus of claim 11, in which the at least one PDSCH resource element mapping parameter comprises a physical cell identifier, number of cell-specific reference signals (CRS) antenna ports, CRS frequency shift, Multimedia Broadcast Single Frequency Network (MBSFN) subframe configuration, or a PDSCH starting symbol and PDSCH resource allocation.

13. An apparatus for wireless interference mitigation within a first User Equipment (UE), the apparatus comprising:

at least one channel estimator for estimating a first channel transfer function associated with a first received signal designated for the first UE, and for estimating a second channel transfer function associated with a second received, interference, signal;

at least one symbol estimator, responsive to the at least one channel estimator, to process at least the first received signal to produce a symbol estimation; and

a demodulator, responsive to the channel estimator, operable to demodulate the symbol estimation to produce an output representing a received data unit corresponding to the symbol estimation;

the demodulator comprising a processing unit arranged to demodulate the symbol estimation using the first channel transfer function and the second channel transfer function,

wherein the at least one symbol estimator comprises a symbol processor arranged to produce a set of signal candidates, ŝ

(t_i), defined as ŝ

(t_i)=slice{(h^hh)<sup>−

1</sup> h^h (r−

g·

t_i)}, where h is the channel transfer function on a given resource element for a serving channel, g is the channel transfer function on a given resource element for the serving channel, r is the received signal, t_i is an element of a set T of all possible interfering signal candidates, the superscript h represents a Hermitian transpose, and the superscript −

1 represents a matrix inverse.

14. The apparatus of claim 13, wherein the demodulator processing unit evaluates