Method and apparatus for scheduling resources at relay station (RS) in mobile communication network

• US 9,516,661 B2
• Filed: 08/06/2014
• Issued: 12/06/2016
• Est. Priority Date: 08/07/2013
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: O'Reilly, Jim, Hadef, Mahmoud, Kim, Kwang Taik, Jang, Kyung Hun
• Primary Examiner(s): Ho, Chuong T
• Application Number:
  US14/452,770
• Publication Number:
  US 20150043423A1
• Time in Patent Office: 853 Days
• Field of Search: 370/315, 370/329, 370/330, 455/7
• US Class Current: 1/1
• CPC Class Codes: H04B 7/14 Relay systems
• CPC Class Codes: H04L 5/0044 allocation of payload
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04L 5/0057 Physical resource allocation for CQI
• CPC Class Codes: H04L 5/0094 Indication of how sub-channels of the path are allocated
• CPC Class Codes: H04W 72/52 based on load
• CPC Class Codes: H04W 72/542 using measured or perceived quality
• CPC Class Codes: H04W 84/047 using dedicated repeater stations

Abstract

A Relay Station (RS), and a corresponding method of performing scheduling at an RS in a mobile communication network are provided. The RS and corresponding method receive channel state information and scheduling information from an apparatus associated with the RS, the scheduling information defining scheduling parameters for downlink transmission of data. The RS and corresponding method also obtain updated scheduling parameters based on the scheduling information, the channel state information, and an amount of the data.

Claims

1. A method to perform scheduling at a relay station (RS), the method comprising:

receiving, by the RS, channel state information from a mobile station (MS) and scheduling information from a base station (BS), the scheduling information comprising scheduling parameters for downlink transmission of downlink data; and

updating, by the RS, the received scheduling parameters based on the scheduling information, the channel state information, and an amount of the downlink data;

transmitting, by the RS, a portion of the downlink data to the MS based on the updated scheduling parameters.

2. The method of claim 1, wherein the updating comprises

identifying available scheduling parameters that require an amount of data that is less than or equal to the amount of the data;

and

selecting the updated scheduling parameters from among the available scheduling parameters based on a condition.

3. The method of claim 2, wherein the selecting comprises at least one of

selecting the updated scheduling parameters that provide a maximum throughput from among the available scheduling parameters;

or

selecting the updated scheduling parameters that provide a determined Quality of Service (QoS).

4. The method of claim 1, further comprising:

calculating a difference between a current value of a channel quality metric and a previously received value of the channel quality metric, the channel state information comprising the channel quality metric; and

transmitting the difference as the channel state information to at least one of the base station (BS) or an intermediate RS.

5. The method of claim 1, further comprising:

quantizing the channel state information by adjusting the channel state information to one of defined levels; and

transmitting the quantized channel state information to at least one of the base station (BS) or an intermediate RS.

6. The method of claim 5, further comprising:

selecting at least one of a lower number of the defined levels for a higher number of hops on a multi-hop chain between the mobile station (MS) and the base station (BS), or a lower number of the defined levels for higher channel fading conditions.

7. The method of claim 1, further comprising:

obtaining predicted channel state information of a state of a communication channel between the RS and an apparatus in a current time period based on the received channel state information,

wherein the channel state information comprises information on a state of the communication channel in a previous time period, and

wherein the received scheduling parameters are updated based on the predicted channel state information.

8. The method of claim 1, wherein the RS operates based on a decode-and-forward (DF) relay scheme, and

wherein the updating further comprises obtaining a new modulation scheme and a new coding scheme.

10. The method of claim 1, wherein the scheduling information is used to define a bandwidth (BW) allocated to an apparatus, and

wherein the updating comprises obtaining a new BW for the apparatus from BWs re-allocated to apparatuses.

11. The method of claim 1, further comprising:

receiving downlink data; and

adding the downlink data to a buffer, prior to updating the received scheduling parameters.

9. (BW) allocated to an apparatus, and the defined BW is retained in response to the updating of the received scheduling parameters.

12. A relay station (RS), comprising:

one or more hardware processors coupled to a memory, wherein the memory stores;

a reception module configured to receive channel state information from a mobile station (MS) and scheduling information from a base station (BS), the scheduling information comprising scheduling parameters for downlink transmission of downlink data; and

a scheduling module configured to update the received scheduling parameters based on the scheduling information, the channel state information, and an amount of the downlink data;

a transmitter configured to transmit a portion of the downlink data to the MS based on the updated scheduling parameters.

13. The RS of claim 12, wherein the scheduling module is further configured to:

identify available scheduling parameters that require an amount of data that is less than or equal to the amount of the data, and

select the updated scheduling parameters from among the available scheduling parameters based on a condition.

14. The RS of claim 12, wherein the memory further stores:

a difference calculating module configured to calculate a difference between a current value of a channel quality metric and a previously received value of the channel quality metric, the channel state information comprising the channel quality metric; and

a transmission module configured to transmit the difference as the channel state information to at least one of the base station (BS) or an intermediate RS.

15. The RS of claim 12, wherein the memory further stores:

a quantization module configured to quantize the channel state information by adjusting the channel state information to one of defined levels; and

a transmission module configured to transmit the quantized channel state information to at least one of the base station (BS) or an intermediate RS.

16. The RS of claim 15, wherein the quantization module is further configured to select a lower number of the defined levels in a situation of at least one of:

a higher number of hops on a multi-hop chain between the mobile station (MS) and the base station (BS), or

higher channel fading conditions.

17. The RS of claim 12, wherein the memory further stores:

a prediction module configured to predict the channel state information on a state of a communication channel between the RS and an apparatus in a current time period and based on the received channel state information,

wherein the channel state information comprises information on a state of the communication channel in a previous time period, and

wherein the scheduling module is further configured to update the received scheduling parameters based on the predicted channel state information.

18. The RS of claim 12, wherein the RS is configured to operate based on a decode-and-forward (DF) relay scheme,

wherein the scheduling module is further configured to obtain a modulation scheme and coding scheme among the updated scheduling parameters,

wherein the received scheduling information is used to define a bandwidth (BW) allocated to an apparatus, and

wherein the scheduling module is further configured to retain the defined BW in response to the received scheduling parameters being updated.

19. The RS of claim 12, wherein the RS is further configured to operate based on an amplify-and-forward (AF) relay scheme, and the scheduling module is further configured to obtain a bandwidth (BW) and power allocation in response to the received scheduling parameters being updated, or

wherein the RS is further configured to operate based on a compress-and-forward (CF) relay scheme, and the scheduling module is further configured to obtain the BW and a modulation scheme when the received scheduling parameters are updated.

20. The RS of claim 12, wherein the scheduling module is further configured to update the received scheduling parameters based on at least one of a round-robin process, a proportional fairness process, or an adaptive proportional fairness process.

21. A method of a relay station (RS), comprising:

receiving scheduling information and downlink data from a base station (BS);

receiving channel state information as feedback from a mobile station (MS);

updating pre-stored data with the downlink data;

update scheduling parameters based on the channel state information, the scheduling information, and an amount of the updated data for downlink transmission; and

transmitting a portion of the updated data to the MS based on the updated scheduling parameters.

22. The method of claim 21, wherein the scheduling information comprises scheduling parameters or the updated scheduling parameters that are allocated by the base station (BS) or an intermediate RS.

23. The method of claim 21, wherein the channel state information comprises information on a communication state of a communication channel between the RS and the MS.

24. The method of claim 21, further comprising:

obtaining predicted channel state information of a state of a communication channel in a current time period, based on the channel state information, wherein the channel state information is predicted based on pre-stored feedback information; and

updating the scheduling parameters based on the predicted channel state information.

25. The method of claim 21, wherein the transmitting of the portion of the updated data comprises packaging data based on the updated scheduling parameters, and transmitting the packaged data.