Apparatus and method for adaptive jitter buffers

• US 6,683,889 B1
• Filed: 11/15/1999
• Issued: 01/27/2004
• Est. Priority Date: 11/15/1999
• Status: Expired due to Fees

• Current Assignee: Nokia Solutions and Networks US LLC (Nokia Corporation)
• Original Assignee: Siemens Information & Communication Networks, Inc. (Siemens AG)
• Inventors: Shaffer, Shmuel, Beyda, William J.
• Primary Examiner(s): Jung, Min
• Application Number:
  US09/440,456
• Time in Patent Office: 1,534 Days
• Field of Search: 370/516, 370/517, 370/230.1, 370/232, 370/233, 370/519, 375/371, 375/372, 709/232, 709/233, 709/234, 709/235
• US Class Current: 370/516
• CPC Class Codes: G06F 2205/063 Dynamically variable buffer size
• CPC Class Codes: G06F 5/06 for changing the speed of data flow, i.e. speed regularising or timing, e.g. delay lines, FIFO buffers; over- or underrun control therefor G06F7/78 takes precedence
• CPC Class Codes: H04J 3/0632 Synchronisation of packets and cells, e.g. transmission of voice via a packet network, circuit emulation service [CES] queuing arrangements in packet switching elements H04L49/90; synchronising systems for the synchronous transmission of a pulse code modulated video signal with one or more other pulse code modulated signals H04N7/56
• CPC Class Codes: H04L 12/6418 Hybrid transport
• CPC Class Codes: H04L 2012/6489 Buffer Management, Threshold setting, Scheduling, Shaping
• CPC Class Codes: H04L 7/005 Correction by an elastic buffer

Abstract

A jitter buffer controller allows the depth of the jitter buffer to be adjusted dynamically according to the varying jitter of the current sequence. The contents of the jitter buffer are examined during a transmission. If the delay or average delay within the buffer drops to a predetermined threshold, then the size or depth of the jitter buffer is increased.

Claims

1. A telecommunications method, comprising:

setting a jitter buffer occupancy threshold;

receiving data into a jitter buffer; and

adjusting a depth of said jitter buffer if said jitter buffer occupancy threshold is crossed, said adjusting comprising increasing or decreasing periods of silence.

2. A telecommunications method according to claim 1, said adjusting comprising decreasing said depth.

3. A telecommunications method according to claim 1, including activating a timer upon reception of a packet and stopping said timer upon reception of a next packet.

4. A method according to claim 3, said adjusting comprising employing silence suppression.

5. A telecommunications system, comprising:

a packet network; and

a jitter buffer system, said jitter buffer system including a jitter buffer, a jitter buffer cache, and a jitter buffer controller, said jitter buffer controller configured to monitor packets arrivals and adjust a depth of said jitter buffer if a jitter buffer occupancy crosses a jitter buffer occupancy threshold, said jitter buffer controller adjusting said depth by increasing or decreasing periods of silence.

6. A telecommunications system according to claim 5, wherein said jitter buffer cache is configured to store values corresponding to one or more time intervals, and said jitter buffer controller is configured to average said stored values.

7. A telecommunications system according to claim 6, said jitter buffer controller configured to activate a timer upon reception of a packet and stop said timer upon reception of a next packet.

8. A telecommunications device, comprising:

a jitter buffer;

a jitter buffer cache configured to store one or more values related to time intervals between packets; and

a jitter buffer controller configured to adjust a depth of said jitter buffer by increasing or decreasing periods of silence based on said one or more values stored in said jitter buffer cache.

9. A telecommunications device according to claim 8, said jitter buffer controller further configured to average said one or more values.

10. A telecommunications device according to claim 9, said jitter buffer controller configured to activate a timer upon reception of a packet and stop said timer upon reception of a next packet.