D2D connection recovery schemes

• US 9,066,258 B2
• Filed: 01/28/2013
• Issued: 06/23/2015
• Est. Priority Date: 04/13/2012
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Intel Corporation
• Inventors: Li, Honggang, Li, Qinghua, Zhu, Yuan, Chen, Xiaogang, Fwu, Jong-Kae
• Primary Examiner(s): Hailu, Kibrom T
• Application Number:
  US13/751,252
• Publication Number:
  US 20130272182A1
• Time in Patent Office: 876 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: H04L 12/189 in combination with wireless systems selective distribution or broadcast in wireless communication networks H04W4/06
• CPC Class Codes: H04L 5/0001 Arrangements for dividing the transmission path duplexing H04L5/14; multiplexing of different sources on one path H04J
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04L 5/0037 Inter-user or inter-terminal allocation
• CPC Class Codes: H04L 5/0044 allocation of payload
• 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 5/0064 Rate requirement of the data, e.g. scalable bandwidth, data priority
• CPC Class Codes: H04L 5/0094 Indication of how sub-channels of the path are allocated
• CPC Class Codes: H04L 5/14 Two-way operation using the same type of signal, i.e. duplex
• 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 28/02 Traffic management, e.g. flow control or congestion control
• CPC Class Codes: H04W 28/0226 based on location or mobility handoff or reselection H04W36/00; mobile application services making use of the location of users or terminals H04W4/02
• CPC Class Codes: H04W 28/0268 using specific QoS parameters for wireless networks, e.g. QoS class identifier [QCI] or guaranteed bit rate [GBR] negotiating SLA or negotiating QoS H04W28/24
• CPC Class Codes: H04W 36/0016 Hand-off preparation specially adapted for end-to-end data sessions
• CPC Class Codes: H04W 36/08 Reselecting an access point
• CPC Class Codes: H04W 4/06 Selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS]; Services to user groups; One-way selective calling services
• CPC Class Codes: H04W 4/70 Services for machine-to-machine communication [M2M] or machine type communication [MTC]
• CPC Class Codes: H04W 72/04 Wireless resource allocation
• 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 72/542 : using measured or perceived quality
• CPC Class Codes: H04W 74/0808 : using carrier sensing, e.g. carrier sense multiple access [CSMA]
• CPC Class Codes: H04W 74/0833 : Random access procedures, e.g. with 4-step access
• CPC Class Codes: H04W 76/10 : Connection setup
• CPC Class Codes: H04W 76/19 : Connection re-establishment
• CPC Class Codes: Y02D 30/70 : in wireless communication networks

Abstract

Schemes for recovering D2D connections between terminals (UEs) in an LTE network are described. The schemes may be applied in situations where a D2D connection is established between two UEs but is lost by, for example, one of the UEs entering a sleep state. The schemes may be applied to either centralized or distributed D2D systems. Some of the schemes are eNB-assisted while others are performed solely by the UEs.

Claims

1. A user equipment (UE) device, comprising:

a radio transceiver to provide an air interface for communicating with an eNB (evolved node B) and for D2D (device-to-device) communications; and

processing circuitry connected to the radio transceiver to;

establish a D2D communications session with a second UE,

if a message from the second UE indicates that the second UE is to be entering a sleep state and a wakeup time is received, transmit an acknowledgement message to the second UE and, at the indicated wakeup time, transmit a D2D recovery message to the second UE and wait for a response thereto to re-establish the D2D communications session;

if the D2D communications session with the second UE is lost but no message indicating the wakeup time is received from the second UE, transmit a D2D recovery request to the eNB;

if a response to the D2D recovery request is received from the eNB indicating the next paging time and if the second UE responds to a page at the paging time, transmit a D2D recovery message to the second UE at the paging time and wait for a response thereto to re-establish the D2D communications session.

2. The device of claim 1 wherein the processing circuitry is further to:

after re-establishment of the D2D communications session with the second UE, transmit a message to the eNB indicating that the D2D communications session has been re-stablished.

3. The device of claim 1 wherein the processing circuitry is further to:

if the D2D communications session with the second UE is lost but no message indicating the wakeup time is received from the second UE, transmit a D2D recovery request to the eNB;

if a response to the D2D recovery request is received from the eNB indicating a wakeup time previously transmitted to the eNB by the second UE, transmit a D2D recovery message to the second UE at the wakeup time and wait for a response thereto to re-establish the D2D communications session.

4. The device of claim 1 wherein the processing circuitry is further to:

if requested to do so by the eNB, measure the signal transmitted by the second UE when responding to the page over the physical random access channel (PRACH), and transmit a measurement report back to the eNB; and

,

if authorized to do on by the eNB in response to the transmitted measurement report, transmit a D2D recovery message to the second UE at the paging time and wait for a response thereto to re-establish the D2D communications session.

5. The device of claim 1 wherein the processing circuitry is further to:

if requested to do so by the eNB, measure the signal transmitted by the second UE over an uplink control channel after responding to the page, and transmit a measurement report back to the eNB; and

,

if authorized to do so by the eNB in response to the transmitted measurement report, transmit a D2D recovery message to the second UE at the paging time and wait for a response thereto to re-establish the D2D communications session.

6. A user equipment (UE) device, comprising:

a radio transceiver to provide an air interface for communicating with an eNB (evolved node B) and for D2D (device-to-device) communications; and

processing circuitry connected to the radio transceiver to;

establish a D2D communications session with a second UE;

if a message from the second UE indicates that the second UE is to be entering a sleep state and a wakeup time is received, transmit an acknowledgement message to the second UE and, at the indicated wakeup time, transmit a D2D recovery message to the second UE and wait for a response thereto to re-establish the D2D communications session;

if the D2D communications session with the second UE is lost but no message indicating the wakeup time is received from the second UE, transmit a D2D recovery request to the eNB;

if a response to the D2D recovery request is received from the eNB indicating a wakeup time previously transmitted to the eNB b the second UE, transmit a D2D recovery message to the second UE at the wakeup time and wait for a response thereto to re-establish the D2D communications session.

7. The device of claim 6 wherein the processing circuitry is further to, if a sleep state is to be entered after establishment of the D2D communications session, transmit a message to the eNB indicating a wakeup time.

8. The device of claim 6 wherein the processing circuitry is further to, after re-establishment of the D2D communications session with the second UE, transmit a message to the eNB indicating that the D2D communications session has been re-established.

9. A method for operating a user equipment (UE), comprising:

establishing a device-to device (D2D) communications session with a second UE;

if a message from the second UE indicating that the second UE is to be entering a sleep state is received, negotiating a wakeup time for the second UE to wake from the sleep state; and

transmitting a D2D recovery message to the second UE at the wakeup time and waiting for a response thereto to re-establish the D2D communications session;

if the D2D communications session with the second UE is lost but no message indicating the wakeup time is received from the second UE, transmitting a D2D recovers request to the eNB;

if a response to the D2D recovery request is received from the eNB indicating a wakeup time previously transmitted to the eNB by the second UE, transmitting a D2D recovery message to the second UE at the wakeup time and waiting for a response thereto to re-establish the D2D communications session.

10. The method of claim 9 further comprising:

if a sleep state is to be entered after establishment of the D2D communications session, transmitting a message to the eNB indicating a wakeup time.

11. The method of claim 9 further comprising:

after re-establishment of the D2D communications session with the second UE, transmitting a message to the eNB indicating that the D2D communications session has been re-established.

12. The method of claim 9 further comprising:

measuring the signal transmitted by the second UE in responding to a page over the physical random access channel (PRACH) in response to a request from the eNB.

13. The method of claim 9 further comprising:

measuring the signal transmitted by the second UE after responding to the page over an uplink control channel in response to a request from the eNB.

14. The method of claim 12 further comprising:

receiving a D2D recovery authorization from the eNB if the measurement of the signal transmitted by the second UE is adequate.

15. A method for operating a user equipment (UE), comprising:

establishing a device-to device (D2D) communications session with a second UE;

if a message from the second UE indicating that the second UE is to be entering a sleep state is received, negotiating a wakeup time for the second UE to wake from the sleep state; and

transmitting a D2D recovery message to the second UE at the wakeup time and waiting for a response thereto to re-establish the D2D communications session;

if the D2D communications session with the second UE is lost but no message indicating the wakeup time is received from the second UE, transmitting a D2D recovery request to an eNB;

if a response to the D2D recovery request is received from the eNB indicating the next paging time and if the second UE responds to a page at the paging time, transmitting a D2D recovery message to the second UE at the paging time and waiting for a response thereto to re-establish the D2D communications session.

16. The method of claim 15 further comprising:

after re-establishment of the D2D communications session with the second UE, transmitting a message to the eNB indicating that the D2D communications session has been re-established.

17. The method of claim 15 further comprising:

if the D2D communications session with the second UE is lost but no message indicating the wakeup time is received from the second UE, transmitting a D2D recovery request to an eNB;

if a response to the D2D recovery request is received from the eNB indicating a wakeup time previously transmitted to the eNB by the second UE, transmitting a D2D recovery message to the second UE at the wakeup time and waiting for a response thereto to re-establish the D2D communications session.

18. The method of claim 16 further comprising:

if requested to do so by the eNB, measuring the signal transmitted by the second UE when responding to the page over the physical random access channel (PRACH), and transmitting a measurement report back to the eNB; and

,

if authorized to do so by the eNB in response to the transmitted measurement report, transmitting a D2D recovery message to the second UE at the paging time and waiting for a response thereto to re-establish the D2D communications session.

19. The method of claim 16 further comprising:

if requested to do so by the eNB, measuring the signal transmitted by the second UE over an uplink control channel after responding to the page, and transmitting a measurement report back to the eNB; and

,

if authorized to do so by the eNB in response to the transmitted measurement report, transmitting a D2D recovery message to the second UE at the paging time and waiting for a response thereto to re-establish the D2D communications session.

20. The method of claim 15 further comprising:

if a sleep state is to be entered after establishment of the D2D communications session with the second UE, transmitting a message to the second UE indicating a wakeup time;

if an acknowledgement message is received from the second UE in response to transmission of the wakeup time thereto and if a D2D recovery request is received from the second UE at the wakeup time, responding to the D2D recovery request to re-establish the D2D communications session.