CHANNEL STATE INFORMATION FEEDBACK METHOD AND USER EQUIPMENT

• US 20130286881A1
• Filed: 01/19/2012
• Published: 10/31/2013
• Est. Priority Date: 01/20/2011
• Status: Abandoned Application

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Ding, Ming, Huang, Lei, Yang, Zeng, Liu, Renmao
• Application Number:
  US13/978,220
• Publication Number:
  US 20130286881A1
• Time in Patent Office: Days
• US Class Current: 370/252
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 28/04 Error control
• CPC Class Codes: H04W 8/24 Transfer of terminal data
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

A Channel State Information (CSI) feedback method and a User Equipment (UE) are disclosed. The method comprises the following steps of: determining a set of coordinated Base Stations (BSs) participating multi-BS coordination, the set of coordination BSs containing a serving BS and at least one non-serving BS; for each BS in the set of coordinated BSs: calculating a Signal to Interference and Noise Ratio (SINR) for a channel between a UE and the BS based on a hypothetical BS coordination mode corresponding to the BS; and deriving a Channel Quality Index (CQI) corresponding to the calculated SINR and feeding back the derived CQI to the serving BS.

Claims

1. A Channel State Information (CSI) feedback method, comprising the following steps of:

determining a set of coordinated Base Stations (BSs) participating multi-BS coordination, the set of coordination BSs containing a serving BS and at least one non-serving BS;

for each BS in the set of coordinated BSs;

calculating a Signal to Interference and Noise Ratio (SINR) for a channel between a UE and the BS based on a hypothetical BS coordination mode corresponding to the BS; and

deriving a Channel Quality Index (CQI) corresponding to the calculated SINR and feeding back the derived CQI to the serving BS.

2. The method according to claim 1, wherein in the step of calculating SINR:

the hypothetical BS coordination mode corresponding to the serving BS in the set of coordinated BSs is a single BS transmission mode without coordination.

3. The method according to claim 1, wherein in the step of calculating SINR:

the hypothetical BS coordination mode corresponding to each non-serving BS in the set of coordinated BSs is one of a single BS transmission mode without coordination, a multi-BS joint transmission mode, a coordinated beamforming/coordinated scheduling mode and a dynamic cell selection mode.

4. The method according to claim 3, wherein in the step of calculating SINR:

an SINR for a non-serving BS is calculated in consideration of interferences from all other non-serving BSs in the set of coordinated BSs than the non-serving BS.

5. The method according to claim 3, wherein in the step of calculating SINR:

an SINR for a non-serving BS corresponding to the multi-BS joint transmission mode, the coordinated beamforming/coordinated scheduling mode or the dynamic cell selection mode is calculated in consideration of background interference and noise only.

6. The method according to claim 3, further comprising:

feeding back phase information associated with each non-serving BS corresponding to the multi-BS joint transmission mode to the serving BS.

7. The method according to claim 1, wherein the step of deriving CQI comprises:

deriving a CQI corresponding to the calculated SINR based on a mapping relationship between SINR and CQI.

8. The method according to claim 7, wherein the mapping relationship is obtained by shifting and extended filling a modulation and coding table in a Long Term Evolution (LTE) system.

9. The method according to claim 7, wherein the mapping relationship is obtained by selecting, at non-linear intervals, and extended filling a modulation and coding table in a Long Term Evolution (LTE) system.

10. A User Equipment (UE), comprising:

a coordinated BS set determining unit configured for determining a set of coordinated Base Stations (BSs) participating multi-BS coordination, the set of coordination BSs containing a serving BS and at least one non-serving BS;

a Signal to Interference and Noise Ratio (SINR) calculating unit configured for calculating, for each BS in the set of coordinated BSs, an SINR for a channel between a UE and the BS based on a hypothetical BS coordination mode corresponding to the BS;

a Channel Quality Index (CQI) deriving unit configured for deriving, for each BS in the set of coordinated BSs, a CQI corresponding to the calculated SINR; and

a feedback unit configured for feeding back the derived CQI to the serving BS.

11. The UE according to claim 10, wherein the SINR calculating unit is configured for:

setting the hypothetical BS coordination mode corresponding to the serving BS in the set of coordinated BSs as a single BS transmission mode without coordination.

12. The UE according to claim 10, wherein the SINR calculating unit is configured for:

setting the hypothetical BS coordination mode corresponding to each non-serving BS in the set of coordinated BSs as one of a single BS transmission mode without coordination, a multi-BS joint transmission mode, a coordinated beamforming/coordinated scheduling mode and a dynamic cell selection mode.

13. The UE according to claim 12, wherein the SINR calculating unit is configured for:

calculating an SINR for a non-serving BS in consideration of interferences from all other non-serving BSs in the set of coordinated BSs than the non-serving BS.

14. The UE according to claim 12, wherein the SINR calculating unit is configured for:

calculating an SINR for a non-serving BS corresponding to the multi-BS joint transmission mode, the coordinated beamforming/coordinated scheduling mode or the dynamic cell selection mode in consideration of background interference and noise only.

15. The UE according to claim 12, the feedback unit is further configured for:

feeding back phase information associated with each non-serving BS corresponding to the multi-BS joint transmission mode to the serving BS.

16. The UE according to claim 10, wherein the CQI deriving unit is configured for:

deriving a CQI corresponding to the calculated SINR based on a mapping relationship between SINR and CQI.

17. The UE according to claim 16, wherein the CQI deriving unit is further configured for:

obtaining the mapping relationship by shifting and extended filling a modulation and coding table in a Long Term Evolution (LTE) system.

18. The UE according to claim 16, wherein the CQI deriving unit is further configured for:

obtaining the mapping relationship by selecting, at non-linear intervals, and extended filling a modulation and coding table in a Long Term Evolution (LTE) system.