Method and apparatus for scheduling user equipment

Patent metadata

Field	Value
Publication number	US-9532371-B2
Application number	US-201214345139-A
Country	US
Kind code	B2
Filing date	Mar 23, 2012
Priority date	Mar 23, 2012
Publication date	Dec 27, 2016
Grant date	Dec 27, 2016

Abstract

Embodiments of the disclosure provide a method and apparatus for scheduling a UE, wherein a BS serves the UE and employs a non-normal subframe to coordinate inter-cell interference, and wherein transmission power in the non-normal subframe is lower than that in a normal subframe. In the method according to embodiments of the present invention, channel quality information for the non-normal subframe may be adjusted based on information on transmission power of downlink packets and reference signals; and a target MCS may be determined according to the adjusted channel quality information, so that the BS schedules the UE based on the target MCS in the non-normal subframe.

First claim

What is claimed is:

1. A method for scheduling a user equipment (UE), wherein a base station (BS) serves the UE and employs a first subframe to coordinate inter-cell interference, the first subframe having transmission power lower than that of a second subframe employed by the BS, the method comprising:
adjusting channel quality information for the first subframe based on information on transmission power of downlink packets and reference signals; and
determining a target modulation and coding scheme (MCS) according to the adjusted channel quality information, so that the BS schedules the UE based on the target MCS in the first subframe,
wherein the determining a target MCS according to the adjusted channel quality information comprises:
selecting a candidate MCS from a CQI-MCS mapping table based on the adjusted channel quality information; and
determining the target MCS based on the candidate MCS and a power control dynamic range, wherein the power control dynamic range comprises at least one dynamic level for at least one modulation mode, and
wherein the determining the target MCS based on the candidate MCS and power control range comprises:
comparing the power control range and the information on transmission power of downlink packets and reference signals;
in response to that the information on transmission power of downlink packets and reference signals exceeds the power control range, determining a MCS with least requirements in the CQI-MCS mapping table as the target MCS; and
in response to that the information on transmission power of downlink packets and reference signals does not exceed the power control range,
if the information on transmission power of downlink packets and reference signals does not exceed the dynamic level for a modulation mode of the candidate MCS, determining the candidate MCS as the target MCS, and
if the information on transmission power of downlink packets and reference signals exceeds the dynamic level for a modulation mode of the candidate MCS, determining a MCS with less requirements than the candidate MCS in the CQI-MCS mapping table as the target MCS, wherein the target MCS has different modulation mode from the candidate MCS.

2. The method of claim 1 , wherein adjusting channel quality information for first subframe based on information on transmission power of downlink packets and reference signals comprises:
obtaining a signal to interference plus noise ratio (SINR) for transmission from the BS to the UE; and
adjusting the SINR based on the information on transmission power of downlink packets and reference signals.

3. The method of claim 2 , wherein obtaining a SINR for the transmission from the BS to the UE comprises:
receiving a Channel Quality Indicator (CQI) measured by the UE; and
obtaining the SINR corresponding to the received CQI.

4. The method of claim 2 , wherein obtaining a SINR for the transmission from the BS to the UE comprises:
receiving reference signals from the BS; and
measuring the SINR based on the received reference signals.

5. The method of claim 1 , further comprising:
scheduling the UE by using the target MCS; and
sending packets to the UE based on the scheduling result.

6. The method of claim 1 , further comprising:
transmitting, to the UE, the information on transmission power of downlink packets and reference signals, so that the UE decodes packets transmitted from the BS based on the information on transmission power of downlink packets and reference signals.

7. The method of claim 1 , further comprising:
obtaining a target CQI based on the target MCS; and
reporting the target CQI to the BS, so that the BS obtains the target MCS based on the target CQI, schedules the UE by using the target MCS, and sends packets to the UE based on the scheduling result.

8. The method of claim 1 , further comprising:
receiving from the BS the information on transmission power of downlink packets and reference signals.

9. The method of claim 1 , wherein the information on transmission power of downlink packets and reference signals comprises ratio of Physical Downlink Shared Channel (PDSCH) energy per resource element (EPRE) to reference signal (RS) EPRE.

10. An apparatus for scheduling a user equipment (UE), wherein a base station (BS) serves the UE and employs a first subframe to coordinate inter-cell interference, the first subframe having transmission power lower than that of a second subframe employed by the BS, the apparatus comprising:
adjusting unit configured to adjust channel quality information for the first subframe based on information on transmission power of downlink packets and reference signals; and
determining unit configured to determine a target modulation and coding scheme (MCS) according to the adjusted channel quality information, so that the BS schedules the UE based on the target MCS in the first subframe,
wherein the determining unit comprises:
selecting means configured to select a candidate MCS from a CQI-MCS mapping table based on the adjusted channel quality information; and
determining means configured to determine the target MCS based on the candidate MCS and a power control dynamic range, wherein the power control dynamic range comprises at least one dynamic level for at least one modulation mode, and
wherein the determining means comprises:
means configured to compare the power control range and the information on transmission power of downlink packets and reference signals;
means configured to, in response to that the information on transmission power of downlink packets and reference signals exceeds the power control range, determine a MCS with least requirements in the CQI-MCS mapping table as the target MCS; and in response to that the information on transmission power of downlink packets and reference signals does not exceed the power control range,
if the information on transmission power of downlink packets and reference signals does not exceed the dynamic level for a modulation mode of the candidate MCS, determine the candidate MCS as the target MCS, and
if the information on transmission power of downlink packets and reference signals exceeds the dynamic level for a modulation mode of the candidate MCS, determine a MCS with less requirements than the candidate MCS in the CQI-MCS mapping table as the target MCS, wherein the target MCS has different modulation mode from the candidate MCS.

11. The apparatus of claim 10 , wherein the adjusting unit comprises:
obtaining means configured to obtain a signal to interference plus noise ratio (SINR) for transmission from the BS to the UE; and
adjusting means configured to adjust the SINR based on the information on transmission power of downlink packets and reference signals.

12. The apparatus of claim 11 , wherein the obtaining means comprises:
means configured to receive a Channel Quality Indicator (CQI) measured by the UE; and
means configured to obtain the SINR corresponding to the received CQI.

13. The apparatus of claim 11 , wherein the obtaining means comprises:
means configured to receive reference signals from the BS; and
means configured to measure the SINR based on the received reference signals.

14. The apparatus of claim 10 , further comprising:
scheduling unit configured to schedule the UE by using the target MCS; and
sending unit configured to send packets to the UE based on the scheduling result.

15. The apparatus of claim 10 , further comprising:
transmitting unit configured to transmit, to the UE, the information on transmission power of downlink packets and reference signals, so that the UE decodes

Assignees

• Wang Gang
• Jiang Lei
• Lei Ming
• Nec (China) Co Ltd

Inventors

• Wang Gang
• Jiang Lei
• Lei Ming

Classifications

• H04W72/542 Primary

  using measured or perceived quality · CPC title

• H04W72/54

  based on quality criteria · CPC title

• H04L1/0003 Primary

  by switching between different modulation schemes · CPC title

• H04L1/0015

  characterised by the adaptation strategy · CPC title

• H04L5/0057

  Physical resource allocation for CQI · CPC title