Scalable broadband group call via unicast downlink traffic consolidation and local re-broadcast

• US 9,001,703 B2
• Filed: 11/12/2012
• Issued: 04/07/2015
• Est. Priority Date: 11/12/2012
• Status: Active Grant

• Current Assignee: Motorola Solutions, Inc.
• Original Assignee: Motorola Solutions, Inc.
• Inventors: Kuehner, Nathanael P.
• Primary Examiner(s): Abelson, Ronald B
• Application Number:
  US13/674,304
• Publication Number:
  US 20140133318A1
• Time in Patent Office: 876 Days
• Field of Search: 370/260, 370/261, 370/270
• US Class Current: 370/262
• CPC Class Codes: H04W 4/023 using mutual or relative location information between multiple location based services [LBS] targets or of distance thresholds
• 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 4/10 Push-to-Talk [PTT] or Push-On-Call services
• CPC Class Codes: H04W 76/45 for Push-to-Talk [PTT] or Push-to-Talk over cellular [PoC] services
• CPC Class Codes: H04W 88/04 adapted for relaying to or from another terminal or user

Abstract

A method, system, and device consolidate unicast downlinks in a broadband radio access network (RAN) for a requested group call. A subset of subscriber devices of the group in sufficiently close proximity is detected, one subscriber device in the subset is selected to act as a subscriber device to subscriber device broadcast downlink repeater (SD-BDR), and group call data is transmitted to each subscriber not in a subset via a separate unicast downlink, and to each subset via a single outbound unicast link to the selected subscriber device. The selected SD-BDR in each subset then re-broadcasts the group call data to the other members of the subset, thereby reducing outbound broadband resource usage in the broadband RAN.

Claims

1. A method for dynamically consolidating unicast downlinks in a broadband radio access network (RAN) for a requested group call, the method comprising:

receiving, at a call controller, a group call request for a group call from a requesting device;

identifying, by the call controller, a plurality of target subscriber devices indicated by the group call request for participation in the group call;

identifying, by the call controller, at least a first subset of target subscriber devices out of the plurality of target subscriber devices that are determined to be within an air-interface downlink wireless communication range of at least one other target subscriber device in the first subset and identifying, by the call controller, each target subscriber device not in a subset;

selecting, by the call controller, one of the plurality of target subscriber devices in the first subset as a subscriber device to subscriber device broadcast downlink repeater (SD-BDR) for all of the other target subscriber devices in the first subset, informing the selected one of the plurality of target subscriber devices in the first subset that it is the selected SD-BDR for the first subset and instructing the SD-BDR on at least one of a frequency and timeslot on which to locally broadcast provided group call data;

informing, by the call controller, the other target subscriber devices in the first subset that they are to receive the group call via the selected SD-BDR;

receiving, by the call controller from the requesting device, group call data associated with the requested group call; and

providing, by the call controller, the group call data received from the requesting device to each target subscriber device in each identified subset via a corresponding single unicast downlink in the RAN to the subset'"'"'s corresponding selected SD-BDR and to each target subscriber device not in a subset via corresponding separate single unicast downlinks in the RAN.

2. The method of claim 1, further comprising receiving acknowledgements relative to the provided group call data from each of the target subscriber devices via separate respective unicast uplinks.

3. The method of claim 1, wherein identifying the at least first subset of target subscriber devices further comprises:

receiving geographic location information from each of the plurality of target subscriber devices and identifying the first subset of target subscriber devices as those providing geographic location information indicating that they are within a predetermined threshold geographic distance from a candidate SD-BDR.

4. The method of claim 3, wherein the predetermined threshold geographic distance is between 0.1 and 10 miles.

5. The method of claim 3, wherein the geographic location information is provided periodically by each of the target subscriber devices.

6. The method of claim 3, wherein the geographic location information is provided upon request by a group call processing device.

7. The method of claim 1, wherein identifying the at least first subset of target subscriber devices out of the plurality of target subscriber devices that are determined to be within a wireless communication range of each other comprises:

transmitting an instruction to at least one of the target subscriber devices in the first subset to broadcast a beacon signal to surrounding subscriber devices and identifying the first subset of target subscriber devices as those indicating that they detected the beacon signal.

8. The method of claim 7, wherein identifying the first subset of target subscriber devices further comprises identifying those indicating that they detected the beacon signal at a predetermined minimum threshold signal to noise ratio (SNR).

9. The method of claim 8, wherein the predetermined minimum threshold SNR is 10-15 dB.

10. The method of claim 1, wherein identifying the at least first subset of target subscriber devices out of the plurality of target subscriber devices that are determined to be within a wireless communication range of each other comprises:

transmitting an instruction to a plurality of the target subscriber devices in the first subset to broadcast a beacon signal to surrounding subscriber devices and selecting the SD-BDR as a function of a determined number of target subscriber devices that report receiving each beacon signal and a measured signal to noise ratio (SNR) reported by each target subscriber device for each beacon signal received.

11. The method of claim 1, wherein the broadband network is a long term evolution (LTE) network, and the unicast downlinks include LTE air interface downlinks.

12. The method of claim 1, further comprising:

receiving a notification from a particular one of the target subscriber devices in the first subset that it is one or both of no longer within range of the selected SD-BDR and not receiving group call data from the selected SD-BDR, and responsively, providing subsequent group call data directly to the particular one of the target subscriber devices via a corresponding separate single unicast downlink.

13. The method of claim 1, further comprising all of the target subscriber devices in the first subset maintaining separate unicast uplinks in the RAN.

14. The method of claim 1, further comprising:

the call controller instructing the target subscriber devices in the first subset on the at least one of the frequency and timeslot on which to locally receive the group call data provided by the selected SD-BDR.

15. A method at a subscriber device to subscriber device broadcast downlink repeater (SD-BDR) capable subscriber device configured to aid a broadband radio access network (RAN) in consolidating unicast downlinks for a requested group call, the method comprising:

responsive to receiving a request from a call controller, one of (i) determining a geographic location of the SD-BDR capable subscriber device and providing the geographic location of the SD-BDR capable subscriber device to the call controller and (ii) broadcasting a beacon to nearby subscriber devices, receiving beacons broadcast from the nearby subscriber devices, and reporting measured beacon parameters of the beacons broadcast from the nearby subscriber devices to the call controller;

receiving an instruction from the call controller indicating that the SD-BDR capable subscriber device has been selected by the call controller to rebroadcast received group call data associated with the requested group call to other target subscriber devices in a first subset of subscriber devices identified by the call controller, the instruction identifying at least one of a local frequency and time slot on which to rebroadcast the group call data;

receiving the group call data from call controller via a single unicast downlink in the RAN;

playing back the group call data at the SD-BDR capable subscriber device via one of an output transducer and a display; and

rebroadcasting the group call data locally to the other target subscriber devices in the first subset on the one of the local frequency and time slot.

16. The method of claim 15, wherein the RAN is a broadband RAN and the SD-BDR capable subscriber device rebroadcasts the group call data locally via one of a DMR compliant protocol, a P25 compliant protocol, a Wi-Fi compliant protocol, a WiMAX compliant protocol, and a TETRA compliant protocol.

17. The method of claim 15, further comprising providing acknowledgments to the call controller acknowledging receipt of the group call data via a separate air-interface uplink in the broadband RAN established for the SD-BDR, and refraining from providing any group call data acknowledgments to the call controller on behalf of the target subscriber devices receiving the locally rebroadcast group call data.

18. The method of claim 17, wherein the target subscriber devices receiving the locally rebroadcast group call data each maintain separate uplinks via the RAN and transmit group data acknowledgments to the call controller via their respective separate uplinks.

19. A network information device (NID) for dynamically consolidating unicast downlinks in a broadband radio access network (RAN) for a requested group call, the NID comprising:

a memory storing executable instructions;

a transceiver; and

a processor that is configured, responsive to executing the executable instructions, to perform a set of functions comprising;

receiving a group call request for a group call from a requesting device via the transceiver;

identifying a plurality of target subscriber devices indicated by the group call request for participation in the group call;

identifying at least a first subset of target subscriber devices out of the plurality of target subscriber devices that are determined to be within an air-interface downlink wireless communication range of at least one other target subscriber device in the first subset and identifying each target subscriber device not in a subset;

selecting one of the plurality of target subscriber devices in the first subset as a subscriber device to subscriber device broadcast downlink repeater (SD-BDR) for all of the other target subscriber devices in the first subset, informing the selected one of the plurality of target subscriber devices in the first subset that it is the selected SD-BDR for the first subset and instructing the SD-BDR on at least one of a frequency and timeslot on which to locally broadcast provided group call data;

informing the other target subscriber devices in the first subset that they are to receive the group call via the selected SD-BDR;

receiving group call data, from the requesting device via the transceiver, associated with the requested group call; and

providing the group call data received from the requesting device to each target subscriber device in each identified subset via the transceiver and a corresponding single unicast downlink in the RAN to the subset'"'"'s corresponding selected SD-BDR and to each target subscriber device not in a subset via the transceiver and corresponding separate single unicast downlinks in the RAN.

20. A subscriber to subscriber device broadcast downlink repeater (SD-BDR) capable subscriber device for dynamically consolidating unicast downlinks in a broadband radio access network (RAN) for a requested group call, the subscriber device comprising:

a memory storing executable instructions;

a first transceiver and a second transceiver; and

a processor that is configured, responsive to executing the executable instructions, to perform a set of functions comprising;

responsive to receiving a request from a call controller, via the first transceiver, one of (i) determine a geographic location of the SD-BDR capable subscriber device and providing the geographic location of the SD-BDR capable subscriber device to the call controller and (ii) broadcasting a beacon to nearby subscriber devices via the second transceiver, receiving beacons broadcast from the nearby subscriber devices via the second transceiver, and reporting measured beacon parameters of the beacons broadcast from the nearby subscriber devices to the call controller via the first transceiver;

receiving an instruction from the call controller, via the first transceiver, indicating that the SD-BDR capable subscriber device has been selected by the call controller to rebroadcast received group call data associated with the requested group call to other target subscriber devices in a first subset of subscriber devices identified by the call controller, the instruction identifying at least one of a local frequency and time slot on which to rebroadcast the group call data;

receiving the group call data from call controller via the first transceiver and a single unicast downlink in the RAN;

playing back the group call data at the SD-BDR capable subscriber device via one of an output transducer and a display; and

rebroadcasting the group call data locally to the other target subscriber devices in the first subset via the second transceiver on the one of the local frequency and time slot.