Method and apparatus for scheduling peer-to-peer communication links

• US 8,787,305 B2
• Filed: 12/29/2011
• Issued: 07/22/2014
• Est. Priority Date: 12/29/2011
• Status: Active Grant

• Current Assignee: Motorola Solutions, Inc.
• Original Assignee: Motorola Solutions, Inc.
• Inventors: Michels, James P., Baker, Michael H.
• Primary Examiner(s): Pham, Chi
• Assistant Examiner(s): Mohebbi, Kouroush
• Application Number:
  US13/339,586
• Publication Number:
  US 20130170468A1
• Time in Patent Office: 936 Days
• Field of Search: None
• US Class Current: 370/330
• CPC Class Codes: H04W 72/542 using measured or perceived quality
• CPC Class Codes: H04W 76/14 Direct-mode setup

Abstract

An evolved Node B creates or updates peer sets from measured performance information received from one or more stations. The measured performance information includes at least one quality metric associated with a downlink signal sent from the evolved Node B to the one or more stations. The evolved Node B determines excluded timeslots and preferred timeslots based on current resource assignments in each timeslot and based on the peer sets, marks potential resources in an uplink portion of a resource allocation map, and allocates one of the potential resources for peer-to-peer communication between a transmitter station and one or more receiver stations.

Claims

1. A method in a network node for allocating resources for peer-to-peer communications, the method comprising:

creating or updating peer sets, in the network node, from measured performance information received from one or more stations, wherein the measured performance information includes at least one quality metric associated with a downlink signal sent from the network node to the one or more stations;

determining, based on the measured performance information, whether the network node is a high impact peer of a low impact peer of a peer-to-peer communication transmit station;

determining, in the network node, a preferred timeslot for both a peer-to-peer communication among medium or high impact peer stations and a downlink communication by the network node based on current resource assignments in each timeslot, the peer sets, and the determination of whether the network node is a high impact peer or a low impact peer of each station associated with the peer-to-peer communication;

marking, in the network node, potential resources in a peer-to-peer portion of a resource allocation map based on the determination of the preferred timeslot; and

allocating, in the network node, one of the potential resources for peer-to-peer communication between a transmitter station and one or more receiver stations.

2. The method of claim 1, wherein peer-to-peer communication links between the transmitter station and the one or more receiver stations are on a same frequency channel, unique peer-to-peer communication links between the transmitter station and the one or more receiver stations are on different frequency channels simultaneously or distinct peer-to-peer communication links between one or more transmitter stations and the one or more receiver stations occupy different frequency channels simultaneously when the designated peer-to-peer resources span more than one frequency channel.

3. The method of claim 1, wherein the allocating comprises designating portions of uplink and downlink timeslots in a frame for peer-to-peer communication,

wherein when a percentage of timeslots used for downlink communication is greater than a downlink loading threshold, any existing zone designated exclusively for peer-to-peer traffic is removed from a downlink portion of the frame and when the percentage of timeslots used for downlink communication is less than the downlink loading threshold, a zone within the downlink portion of the frame is set aside exclusively for peer-to-peer communication;

and

wherein when a percentage of timeslots used for uplink communication is greater than a uplink loading threshold, any existing zone designated exclusively for peer-to-peer traffic is removed from a uplink portion of the frame and when the percentage of timeslots used for uplink communication is less than the uplink loading threshold, a zone within the uplink portion of the frame is set aside exclusively for peer-to-peer communication.

4. The method of claim 3, wherein the allocating further comprises determining that one or more stations that are medium or high impact peers of each other do not list the node as a high impact peer and designating timeslots in a downlink portion of the frame as a peer-to-peer resource or removing peer-to-peer designated resources from the downlink portion of the frame when there are no stations in proximity to each other that do not list the node as a high impact peer.

5. The method of claim 4, wherein the allocating further comprises determining that one or more stations is capable of receiving a predefined modulation and designating a portion of timeslot with the uplink portion of the frame as a peer-to-peer resource or removing a resource designated as a peer-to-peer resource from the uplink portion of the frame when no station is capable of receiving the predefined modulation.

6. The method of claim 1, wherein a modulation transmitted by the transmitter station to the one or more receiver stations is compatible with an existing time coincident transmission when an allocated peer-to-peer resource is taken from a uplink portion or a downlink portion of a frame, wherein the uplink portion or the downlink portion is not exclusive to peer-to-peer communication links or

wherein the modulation transmitted by the transmitter station to the one or more receiver stations is a predefined modulation that is different from an uplink modulation or a downlink modulation, wherein the uplink portion or the downlink portion is exclusive to peer-to-peer communication links.

7. The method of claim 1, where potential resources in the peer-to-peer portion of the resource allocation map originate from at least one portion of a frame partitioned for uplink, downlink or dedicated peer-to-peer communication links.

8. The method of claim 1, wherein the allocating comprises allowing downlink peer-to-peer transmission to compete with transmissions from the node to the one or more stations or allowing uplink peer-to-peer transmission to compete with transmissions from the one or more stations to the node.

9. The method of claim 1, wherein the determining comprises selecting a preferred peer link as a link where both the transmitter station and a receiver station are low impact peers of the node and are medium or high impact peers of each other and wherein a downlink transmission from the node to the transmitter station or the receiver station can occur in the same timeslot as peer-to-peer communication between the transmitter station and the receiver station.

10. The method of claim 1, wherein the allocating comprises reallocating resources when one or more selected communication links between the transmitter station and the one or more receiver stations are insufficient to maintain communications between the transmitter station and the one or more receiver stations.

11. The method of claim 1, wherein the peer sets are groups as one of high impact, middle impact, or low impact,

wherein a high impact peer set has a high probability of having a near-far problem, a medium impact peer set has a medium probability of having the near-far problem and a low impact peer set has a low probability of having the near far problem.

12. The method of claim 1, wherein the creating comprises:

generating a resource information element to obtain measurements for specified performance metrics from a station;

receiving a resource map response message from the station with the specified performance metrics; and

processing the resource map response message to determine peer-to-peer resources to be allocated to the station.

13. A node configured to allocate resources for peer-to-peer communications, the node comprising:

a creating unit configured to create or update peer sets from measured performance information received from one or more stations, wherein the measured performance information includes at least one quality metric associated with a downlink signal sent from a node to the one or more stations;

a determining unit configured to determine, based on the measured performance information, whether the network node is a high impact peer of a low impact peer of a peer-to-peer communication transmit station and determine a preferred timeslot for both a peer-to-peer communication among medium or high impact peer stations and a downlink communication by the network node based on current resource assignments in each timeslot, the peer sets, and the determination of whether the network node is a high impact peer or a low impact peer of each station associated with the peer-to-peer communication;

a marking unit configured to mark potential resources in a peer-to-peer portion of a resource allocation map based on the determination of the preferred timeslot; and

an allocating unit configured to allocate one of the potential resources for peer-to-peer communication between a transmitter station and one or more receiver stations.

14. The node of claim 13, wherein the allocating unit is configured to

designate portions of uplink and downlink timeslots in a frame for peer-to-peer communication,

wherein when a percentage of timeslots used for downlink communication is greater than a downlink loading threshold, any existing zone designated exclusively for peer-to-peer traffic is removed from a downlink portion of the frame and when the percentage of timeslots used for downlink communication is less than the downlink loading threshold, a zone within the downlink portion of the frame is set aside exclusively for peer-to-peer communication;

and

wherein when a percentage of timeslots used for uplink communication is greater than a uplink loading threshold, any existing zone designated exclusively for peer-to-peer traffic is removed from a uplink portion of the frame and when the percentage of timeslots used for uplink communication is less than the uplink loading threshold, a zone within the uplink portion of the frame is set aside exclusively for peer-to-peer communication.

15. The node of claim 14, wherein the allocating unit is configured to determine that one or more stations that are medium or high impact peers of each other do not list the node as a high impact peer and designating timeslots in a downlink portion of the frame as a peer-to-peer resource or removing peer-to-peer designated resources from the downlink portion of the frame when there are no stations in proximity to each other that do not list the node as a high impact peer.

16. The node of claim 15, wherein the allocating unit is configured to determine that one or more stations is capable of receiving a predefined modulation and designate a portion of timeslot with the uplink portion of the frame as a peer-to-peer resource or remove a resource designated as a peer-to-peer resource from the uplink portion of the frame when no station is capable of receiving the predefined modulation.

17. The node of claim 13, wherein a modulation transmitted by the transmitter station to the one or more receiver stations is compatible with an existing time coincident transmission when an allocated peer-to-peer resource is taken from a uplink portion or a downlink portion of a frame, wherein the uplink portion or the downlink portion is not exclusive to peer-to-peer communication links or

wherein the modulation transmitted by the transmitter station to the one or more receiver stations is a predefined modulation that is different from an uplink modulation or a downlink modulation, wherein the uplink portion or the downlink portion is exclusive to peer-to-peer communication links.

18. The node of claim 13, wherein potential resources in the peer-to-peer portion of the resource allocation map originate from at least one portion of a frame partitioned for uplink, downlink or dedicated peer-to-peer communication links.

19. The node of claim 13, wherein the determining unit is configured to select a preferred peer link as a link where both the transmitter station and a receiver station are low impact peers of the node and are medium or high impact peers of each other and wherein a downlink transmission from the node to the transmitter station or the receiver station can occur in the same timeslot as peer-to-peer communication between the transmitter station and the receiver station.

20. The node of claim 13, wherein the allocating unit is configured to reallocate resources when one or more selected communication links between the transmitter station and the one or more receiver stations are insufficient to maintain communications between the transmitter station and the one or more receiver stations.