System and method for tuning PTT over LTE according to QoS parameters

• US 10,110,342 B2
• Filed: 10/06/2016
• Issued: 10/23/2018
• Est. Priority Date: 10/06/2015
• Status: Active Grant

• Current Assignee: Kodiak Networks Inc (Motorola Solutions, Inc.)
• Original Assignee: Kodiak Networks Inc (Motorola Solutions, Inc.)
• Inventors: Negalaguli, Harisha Mahabaleshwara, Patel, Krishnakant M., Vempati, Brahmananda R.
• Primary Examiner(s): Sobutka, Philip
• Application Number:
  US15/286,784
• Publication Number:
  US 20170099118A1
• Time in Patent Office: 747 Days
• Field of Search: 455518-520
• CPC Class Codes: H04L 1/0017 where the mode-switching is based on Quality of Service requirement
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/0029 Reduction of the amount of signalling, e.g. retention of useful signalling or differential signalling power control H04W52/04
• CPC Class Codes: H04L 67/01 Protocols
• CPC Class Codes: H04W 28/0284 detecting congestion or overload during communication monitoring arrangements H04L43/00
• CPC Class Codes: H04W 4/02 Services making use of location information
• CPC Class Codes: H04W 4/10 Push-to-Talk [PTT] or Push-On-Call services
• CPC Class Codes: H04W 84/08 Trunked mobile radio systems
• CPC Class Codes: H04W 88/02 Terminal devices

Abstract

A system and method for push-to-talk (PTT) over long-term evolution (LTE) includes a method. The method includes receiving, by a push-to-talk (PTT) server, a request from a user equipment (UE) to access the PTT server. The method further includes determining, by the PTT server, quality of service (QoS) parameters for a radio access network (RAN) connecting the UE to the PTT server. The method further includes associating, by the PTT server, the QoS parameters with a bearer between the RAN and the PTT server. The method further includes communicating, by the PTT server, with the UE according to the bearer.

Claims

1. A method comprising:

receiving, by a push-to-talk (PTI) server in a core network (CN), a request from a user equipment (UE) to initiate a PTI call, the UE connected to a radio access network (RAN);

accessing, by the PTI server, a first bearer defining data flow between the CN and the RAN, the first bearer associated with first quality of service (QoS) parameters, the first bearer existing prior to receiving the request from the UE to access the PTI server;

communicating, by the PTI server, initiation traffic for the PTI call with the UE according to the first bearer;

establishing, by the PTI server, a second bearer defining data flow between the CN and the RAN, the second bearer being different from the first bearer;

determining, by the PTI server, second QoS parameters for the second bearer, the second QoS parameters being different from the first QoS parameters, wherein the second QoS parameters include at least one of a physical layer parameter, a media access control layer parameter, a radio link control layer parameter, and a packet data convergence protocol layer parameter for the RAN;

associating, by the PTI server, the second QoS parameters with the second bearer; and

communicating, by the PTI server, media traffic for the PTI call with the UE according to the second bearer.

2. The method of claim 1, wherein the associating the second QoS parameters with the second bearer comprises:

indicating, by the PTI server, a QoS profile associated with the second QoS parameters to a policy and charging rules function (PCRF) in the CN.

3. The method of claim 1, wherein the associating the second QoS parameters with the second bearer comprises:

indicating, by the PTT server, the second QoS parameters to a policy and charging enforcing function (PCEF) in the CN.

4. The method of claim 1, wherein the physical layer parameter indicates the RAN should use transmission time interval (TTI) bundling.

5. The method of claim 1, wherein the media access control layer parameter indicates the RAN should use semi-persistent scheduling (SPS).

6. The method of claim 1, wherein the media access control layer parameter indicates the RAN should use a packet delay budget (PDB) of at least 40 ms, the PDB indicating the RAN should use two hybrid automatic repeat request (HARD) retries.

7. The method of claim 1, wherein the media access control layer parameter indicates the RAN should use a packet delay budget (PDB) of at least 200 ms, the PDB indicating the RAN should increase a modulation and coding scheme (MCS) index or a transmission block size (TBS) index of the RAN.

8. The method of claim 1, wherein the radio link control layer parameter indicates the RAN should operate in acknowledged mode (AM).

9. The method of claim 8, wherein communicating with the UE comprises:

transmitting, by the PTT server, IP packets to the UE, each of the IP packets including

more than one media frame of PTT data.

10. The method of claim 1, wherein the packet data convergence protocol layer parameter indicates the RAN should use robust header compression (RoHC).

11. The method of claim 1, wherein the second QoS parameters indicate a packet delay budget for the second bearer between the RAN and the CN.

12. The method of claim 1, wherein the second QoS parameters are determined by the PTT server such that the RAN has a media access control (MAC) layer error rate of 1% over the second bearer.

13. A method comprising:

receiving, by a gateway in a core network (CN), a request from a user equipment (UE) to initiate a PTT call, the UE connected to a radio access network (RAN);

forwarding, by the gateway, the request from the UE to a PTT server in the CN;

communicating, by the gateway, initiation traffic for the PTT call between the UE and the PTT server according to a first bearer, the first bearer defining data flow between the CN and the RAN, the first bearer associated with first quality of service (QoS) parameters, the first bearer existing prior to receiving the request from the UE to access the PTT server;

receiving, by the gateway, a request from the PTT server to associate second QoS parameters with a second bearer, the second bearer defining data flow between the CN and the RAN, the second bearer being different from the first bearer;

associating, by the gateway, the second bearer with the second QoS parameters; and

communicating, by the gateway, media traffic for the PTT call between the UE and the PTT server according to the second bearer.

14. The method of claim 13, further comprising:

receiving, by the gateway, a request to establish the second bearer from a policy and charging rules function (PCRF) in the CN, the request indicating the second QoS parameters; and

establishing, by the gateway, the second bearer between the RAN and the CN according to the request to establish the second bearer.

15. The method of claim 13, wherein the second QoS parameters include at least one of a physical layer parameter, a media access control layer parameter, a radio link control layer parameter, and a packet data convergence protocol layer parameter for the RAN.

16. The method of claim 15, wherein the physical layer parameter indicates the RAN should use transmission time interval (TTI) bundling.

17. The method of claim 15, wherein the media access control layer parameter indicates the RAN should use semi-persistent scheduling (SPS).

18. The method of claim 15, wherein the media access control layer parameter indicates the RAN should use a packet delay budget (PDB) of at least 40 ms, the PDB indicating the RAN should use two hybrid automatic repeat request (HARQ) retries.

19. The method of claim 15, wherein the media access control layer parameter indicates the RAN should use a packet delay budget (PDB) of at least 200 ms, the PDB indicating the RAN should increase a modulation and coding scheme (MCS) index or a transmission block size (TBS) index of the RAN.

20. The method of claim 15, wherein the radio link control layer parameter indicates the RAN should operate in acknowledged mode (AM).

21. The method of claim 15, wherein communicating with the UE comprises:

forwarding, by the gateway, IP packets from the PTT server to the UE, each of the IP packets including more than one media frame of PTT data.

22. The method of claim 15, wherein the packet data convergence protocol layer parameter indicates the RAN should use robust header compression (RoHC).

23. The method of claim 13, wherein the second QoS parameters indicate a packet delay budget for the second bearer between the RAN and the gateway.

24. A push-to-talk (PTT) server comprising:

one or more processors; and

a computer readable storage medium storing programming for execution by the one or more processors, the programming including instructions to;

receive a request from a user equipment (UE) to initiate a PTT call, the UE connected to a radio access network (RAN), the PTT server being in a core network (CN);

access a first bearer defining data flow between the CN and the RAN, the first bearer associated with first quality of service (QoS) parameters, the first bearer existing prior to receiving the request from the UE to access the PTT server;

communicate initiation traffic for the PTT call with the UE according to the first bearer;

establish a second bearer defining data flow between the CN and the RAN, the second bearer being different from the first bearer;

determine second QoS parameters for the second bearer, the second QoS parameters being different from the first QoS parameters;

associate the second QoS parameters with the second bearer; and

communicate media traffic for the PTT call with the UE according to the second bearer.