Audio packet switching system

• US 20030081594A1
• Filed: 10/30/2002
• Published: 05/01/2003
• Est. Priority Date: 11/01/2001
• Status: Active Grant

• Current Assignee: LG-Ericsson Company Limited (Telefonaktiebolaget LM Ericsson)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Lee, Seok Won
• Granted Patent: US 7,602,769 B2
• Time in Patent Office: Days
• US Class Current: 370/353
• CPC Class Codes: H04L 47/2416 Real-time traffic
• CPC Class Codes: H04L 47/263 Rate modification at the source after receiving feedback
• CPC Class Codes: H04L 47/30 in combination with information about buffer occupancy at either end or at transit nodes
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 65/65 Network streaming protocols, e.g. real-time transport protocol [RTP] or real-time control protocol [RTCP]
• CPC Class Codes: H04L 65/70 Media network packetisation

Abstract

The present invention relates to an IP based or network based audio packet switching system, and more specifically to an audio packet switching system for integrating each independent module into a single interface for consistent control and data flow. Independent modules, such as a RTP/RTCP, encoder/decoder and mixer, are interworked with reception and transmission buffers to make a system more flexible. Additionally, audio data paths inside the switch are controlled through an audio packet router. The multi protocol system employing the RTP provides a single RTP control interface for transmitting and receiving audio packets to completely manage the system totally and raises a degree of resource utilization of the system by making it easy to implement additional functions to the RTP and coder through the buffers.

Claims

1. An audio packet switching system, comprising:

a real time protocol unit including interface functions to perform real time protocol processing and controlling;

a plurality of buffers coupled to correct a transmission speed of audio data transmitted and received irregularly to and from the real time protocol unit, and to correct for data lost during transmission;

an audio coder unit coupled to compress and recover the audio data transmitted and received from the plurality of buffers and to perform data mixing between channels according to a user selection; and

an audio packet router coupled to transmit audio packets received from the audio coder unit and to control data flow, wherein the real time protocol unit, the plurality of buffers, the audio coder unit, and the audio packet router comprise a single integrated system.

2. The system of claim 1, wherein the system is configured to provide packet switching regardless of a signaling protocol.

3. The system of claim 1, wherein each of the plurality of buffers comprises:

a reception buffer to store audio packets received irregularly from the real time protocol unit; and

a transmission buffer to store the audio packets to be transmitted through the real time protocol unit.

4. The system of claim 3, wherein the transmission and reception buffers are configured to correct an irregular transmission speed of the transmitted and received audio data and to process the audio data once or more if the audio data is not transferred completely, and wherein the audio data is transmitted and received through at least one network.

5. The system of claim 4, wherein processing of the audio data if the audio data is not transferred completely comprises inserting data at a position corresponding to lost audio data during transmission and reception process.

6. The system of claim 5, wherein processing the audio data comprises packet loss concealment.

7. The system of claim 5, wherein the audio data is transmitted and received independently of a signaling protocol of the at least one network.

8. The system of claim 3, wherein the real time protocol unit and the audio coder input and output the audio data to corresponding buffers of the plurality of buffers.

9. The system of claim 8, wherein the teal time protocol unit and audio coder can be employed for other uses because the audio data is input and output to the corresponding buffers.

10. The system of claim 1, wherein the audio coder unit comprises:

a decoder to transform audio data received as compressed data in a prescribed scheme according to a protocol of the data into PCM data; and

an encoder to compress the PCM data to be transmitted in the prescribed scheme according to a prescribed protocol.

11. The system of claim 10, further comprising a mixer to mix the transformed PCM data at the decoder with PCM data of another channel according to a user'"'"'s selection.

12. The system of claim 11, wherein the audio mixer interfaces with the reception buffer without regard to the real time protocol unit and carries the mixed data to the reception buffer to mix with audio data of the other channel.

13. The system of claim 10, wherein only the mixing or routing operation is performed without operating the encoder and decoder when a transmitting and receiving unit use a same coder.

14. The system of claim 1, wherein an audio data flow can be controlled inside an audio packet switch by using the audio packet router.

15. An audio switching method, comprising:

setting how to compress data to be transmitted and how to recover data to be received, in an audio coder, by setting parameters of a decoder and an encoder, in order to operate an audio switching system configured to function with any signaling protocol;

setting an audio packet router to enable audio data routing within the audio switching system and to a destination point to which the received audio data is transmitted; and

setting addresses related to a real time protocol between devices between communication is to be established during real time protocol operations.

16. The method of claim 15, further comprising compressing and recovering the received audio packets according to the set audio coder, and transmitting the same to a transmission buffer at the destination point by using an audio packet router.

17. The method of claim 16, further comprising performing additional mixing of the audio packets if further mixing is determined to be necessary.

18. The method of claim 15, wherein an operation of the audio packet router comprises:

receiving input data;

determining if the input data includes a transmission address; and

setting a path to transmit the input data to a transmitting unit under control of a controller if the transmission address is not included in the input data.

19. The method of claim 18, wherein a signaling protocol of a network from which the input data is received is not the same as a signaling protocol of a network to which the input data is to be transmitted.

20. The method of claim 19, wherein the method is performed by a single integrated audio packet switching system.

21. The audio packet switching method according to claim 15, wherein an operation of the audio packet router comprises:

receiving input data;

determining if the input data includes a transmission address to be transmitted; and

transmitting the input data to the transmission address if the transmission address is included in the input data.

22. The method of claim 15, wherein the set operations are cleared by clearing each operation step by step in a reverse procedure to the setting procedure.