Reserved virtual radio conference calling

• US 8,831,662 B2
• Filed: 07/24/2012
• Issued: 09/09/2014
• Est. Priority Date: 07/24/2012
• Status: Active Grant

• Current Assignee: Motorola Solutions, Inc.
• Original Assignee: Motorola Solutions, Inc.
• Inventors: Qi, Ying, He, Shu-Shan, Yang, Zhou, Zhong, Rui
• Primary Examiner(s): Sarwar, Babar
• Application Number:
  US13/556,321
• Publication Number:
  US 20140031019A1
• Time in Patent Office: 777 Days
• Field of Search: 455/414.2, 455415-416, 455418-420, 455/422.1, 455518-519, 455/459, 455/509, 455/450, 455/455, 455/464, 455/41.2, 370260-263, 370/266, 370/270, 379/93.21, 379/158, 379/202.01, 379/205.01
• US Class Current: 455/518
• CPC Class Codes: H04W 4/00 Services specially adapted for wireless communication networks; Facilities therefor
• CPC Class Codes: H04W 4/10 Push-to-Talk [PTT] or Push-On-Call services
• CPC Class Codes: H04W 4/20 Services signaling; Auxiliary data signalling, i.e. transmitting data via a non-traffic channel
• CPC Class Codes: H04W 4/90 Services for handling of emergency or hazardous situations, e.g. earthquake and tsunami warning systems [ETWS]

Abstract

Disclosed is a two-way radio frequency (RF) communications system including a first device that receives, from a first subscriber unit, a virtual radio conferencing call (VRC) request identifying a plurality of other subscriber units to be partied to the VRC call and a conference time period during which to conduct the VRC call. The device reserves RF resources at one or more corresponding radio sites associated with the subscriber units partied to the VRC call for the conference time period. At a beginning of the conference time period, the device causes a virtual radio conference call start message to be transmitted to the subscriber units partied to the call instructing the subscriber units to join the VRC call via the reserved RF resources at their respective radio sites.

Claims

1. In a two-way radio frequency (RF) communications system having a plurality of base stations (BSs), one or more RF channels, and a plurality of subscriber units, a method comprising, at a first device:

receiving, from a first subscriber unit out of the plurality of the subscriber units, a virtual radio conferencing call request identifying (i) a plurality of other subscriber units out of the plurality of the subscriber units requested to be a party to the virtual radio conference call and (ii) a conference time period including a start time and one of an end time and a duration of the virtual radio conference call;

identifying the plurality of the BSs in the RF communications system, each BS associated with at least one of the first subscriber unit and the subscriber units requested to be a party to the virtual radio conference call;

prior to the start time, reserving an RF channel at each of the plurality of identified BSs for the conference time period by storing an indication of each reserved RF channel and associated BS so as to refrain from indicating availability of the each reserved RF channel for the conference time period to future virtual radio conference call requestors; and

subsequently and substantially at a beginning of the conference time period, causing a virtual radio conference call start message to be transmitted, via corresponding the each of the plurality of the identified BSs, to the first subscriber unit and each of the plurality of the other subscriber units instructing the subscriber units to join the virtual radio conference call via the reserved RF channels at their respective BSs.

2. The method of claim 1, wherein the virtual radio conference call start message includes a particular conferencing identifier for use by the subscriber units in joining the virtual radio conference call, wherein the conferencing identifier is a talk group identifier.

3. The method of claim 1, prior to transmitting the virtual radio conference call start message, causing a virtual radio conference call invitation message to be transmitted to the each of the plurality of the other subscriber units including the conference time period and an identity of the reserved RF channel to use in joining the conference call at the subscriber unit'"'"'s associated BS.

4. The method of claim 1, further comprising transmitting a reservation success notification to the first subscriber unit.

5. The method of claim 1, wherein the virtual radio conference call request further includes a priority indication, and reserving RF channels comprises cancelling a previously reserved lower priority second virtual radio conference call and sending notification of the cancellation to one or more participants in the second virtual radio conference call.

6. The method of claim 1, wherein the virtual radio conference call request includes a talkgroup identifier identifying the plurality of other subscriber units out of the plurality of subscriber units requested to participate in the virtual radio conference call.

7. The method of claim 1, wherein the identity of the plurality of other subscriber units includes all subscriber units at two or more particular BSs or all active subscriber units in the two-way RF communications system.

8. The method of claim 1, wherein a software update is transmitted to all subscriber units participating in the virtual radio conference call during the conference time period.

9. The method of claim 1, wherein voice traffic is transmitted between all subscriber units participating in the virtual radio conference call during the conference time period.

10. The method of claim 1, further comprising maintaining a record of at least a subset of available RF channels at the each BS associated with the first subscriber unit and with the each of the plurality of the other subscriber units, and wherein storing the indication of the each reserved RF channel and the associated BS comprises modifying the record to reflect time periods during which all or a portion of the subset of the available RF channels at each BS are assigned to one or more scheduled virtual radio conference calls.

11. The method of claim 1, further comprising the first device determining that a particular one of the plurality of the other subscriber units is active at an associated BS that does not have sufficient available RF channels to reserve during the conferencing time period, responsively sending a notice to the first subscriber unit identifying the particular other subscriber unit and the insufficient availability of RF channels, and subsequently receiving a request from the first subscriber unit to continue with reserving the virtual radio conference call despite the insufficient availability of RF channels.

12. The method of claim 1, further comprising at least one of the identified BSs broadcasting the conferencing start message on a control channel directing each subscriber unit within its coverage area to an RF traffic channel that has been reserved for the virtual radio conference call during the conferencing time period.

13. The method of claim 1, further comprising the identified BSs, for the conference time period, transmitting an uplink busy signal on a downlink channel of the reserved RF channel at the respective BS in order to prevent other subscriber units not partied to the virtual radio conference call from accessing or attempting to access the reserved RF channel during the conference time period.

14. The method of claim 1, wherein the two-way RF communications system is a trunked RF communication system, and the RF channels being reserved are traffic channels.

15. In a two-way radio frequency (RF) communications system having a plurality of base stations (BSs), one or more RF channels, and a plurality of subscriber units, a schedule controller device configured to:

receive, from a first subscriber unit out of the plurality of the subscriber units, a virtual radio conferencing call request identifying (i) plurality of other subscriber units out of the plurality of the subscriber units requested to be a party to the virtual radio conference call and (ii) a conference time period including a start time and one of an end time and a duration of the virtual radio conference call;

identify the plurality of the BSs in the RF communications system, each BS associated with at least one of the first subscriber unit and subscriber units requested to be a party to the virtual radio conference call;

prior to the start time, reserve an RF channel at each of the plurality of identified BSs for the conference time period by storing an indication of each reserved RF channel and associated BS so as to refrain from indicating availability of each reserved RF channel for the conference time period to future virtual radio conference call requestors; and

subsequently and substantially at a beginning of the conference time period, cause a virtual radio conference call start message to be transmitted, via a transmitter and corresponding the each of the plurality of the identified BSs, to the first subscriber unit and each of the plurality of the other subscriber units instructing the subscriber units to join the virtual radio conference call via the reserved RF channels at their respective BSs.

16. The schedule controller device of claim 15, wherein the virtual radio conference call start message includes a particular conferencing identifier for use by the subscriber units in joining the virtual radio conference call, wherein the conferencing identifier is a talk group identifier.

17. The schedule controller device of claim 15, further configured to, prior to transmitting the virtual radio conference call start message, cause a virtual radio conference call invitation message to be transmitted to the each of the other subscriber units including the conference time period and an identity of the reserved RF channel to use in joining the conference call at the subscriber unit'"'"'s associated BS.

18. The schedule controller device of claim 15, wherein the virtual radio conference call request further includes a priority indication, and the schedule controller device is further configured to cancel a previously reserved lower priority second virtual radio conference call and send notification of the cancellation to one or more participants in the second virtual radio conference call.

19. The schedule controller device of claim 15, further configured to:

determine that a particular one of the plurality of the other subscriber units is active at an associated BS that does not have sufficient available RF channels to reserve during the conferencing time period, responsively send a notice to the first subscriber unit identifying the particular other subscriber unit and the insufficient availability of RF channels, and subsequently receive a request from the first subscriber unit to continue with reserving the virtual radio conference call despite the insufficient availability of RF channels.

20. In a two-way radio frequency (RF) communications system having a plurality of base stations (BSs), one or more RF channels, and a plurality of subscriber units, a first subscriber unit configured to:

transmit a new virtual radio conference call request message identifying a plurality of participating subscriber units and a conference time period;

at substantially a beginning of the conference time period, receive a virtual radio conference call start message and responsively join the conference on a reserved RF channel of an associated BS indicated in the virtual radio conference call start message;

during the virtual radio conference call, ignore an uplink busy indication received on a downlink channel of the reserved RF channel to keep other subscriber units not participating in the conference from keying up, and responsive to detecting a user actuation of a push to talk (PTT) button, request transmit authorization and subsequently transmit traffic on the uplink to the other subscriber units participating in the virtual radio conference call; and

responsive to detecting an end call trigger, ends participation in the virtual radio conference call.

21. The first subscriber unit of claim 20, further configured to, responsive to receiving a reservation success message, add the conference time period to a calendar maintained in a data store at the first subscriber unit.