METHOD AND APPARATUS FOR EFFICIENT MULTIMEDIA DELIVERY IN A WIRELESS PACKET NETWORK

• US 20090116458A1
• Filed: 11/01/2007
• Published: 05/07/2009
• Est. Priority Date: 11/01/2007
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Balachandran, Kumar, Frankkila, Tomas, Ramesh, Rajaram
• Granted Patent: US 8,155,090 B2
• Time in Patent Office: Days
• US Class Current: 370/336
• CPC Class Codes: H04L 65/103 in the network
• CPC Class Codes: H04L 65/765 intermediate
• CPC Class Codes: H04L 65/80 Responding to QoS

Abstract

The present invention sends multiple versions of a multimedia packet to the base station, and, based on the radio channel and traffic characteristics, an appropriate version of the multimedia packet is selected to send to the mobile station at a given time. In this way, source transmission is improved to instantaneous conditions. The steps of the present invention are performed in conjunction with RTP used for multimedia transmission over internet protocol (IP) networks. In a first embodiment, the multiple versions are sent to the base station in the same RTP packet, and the base station strips out the extraneous versions. In a second embodiment, the base station receives multiple RTP packets having identical information in the packet header in many fields, and selects an appropriate one among these for transmission to the mobile station, discarding the rest.

Claims

1. A method for improving multimedia delivery over a wireless internet protocol (IP) network, comprising the steps of:

generating multiple versions of a multimedia packet;

sending at least one of the multiple versions of a multimedia packet to a first node in a wireless network; and

selecting an appropriate version of the at least one of the multiple versions of a multimedia packet to send to a second node at a given time.

2. The method of claim 1, wherein the said first node is a base station and the second node is a mobile station.

3. The method of claim 1, wherein the multiple versions of a multimedia packet are generated at a server or an end-terminal.

4. The method of claim 1, wherein the multiple versions of a multimedia packet are generated in a transcoding function in a media gateway.

5. The method of claim 1, in which a packet filter at the first node performs the task of selecting an appropriate version.

6. The method of claim 1, wherein the packet filter is instantiated using a signaling method.

7. The method of claim 1 wherein the multiple versions of a multimedia packet are sent in the same Real-Time Protocol (RTP) packet.

8. The method of claim 7, wherein sub-headers are used to identify the different versions of the multimedia packet sent in the same RTP packet.

9. The method of claim 8, wherein the sub-headers specify timestamp offsets.

10. The method of claim 9, wherein the timestamp offsets are set to zero.

11. The method of claim 10, wherein the first node performs header compression before sending the chosen version of the multimedia packet.

12. The method of claim 7, wherein the RTP packet format according to IETF RFC 2198 is used to send the different versions of the multimedia packet in sub-packets, with the timestamp offsets between the sub-packets set to zero.

13. The method of claim 7, wherein the first node selects the version to send and discards other versions.

14. The method of claim 1, wherein the multiple versions of a multimedia packet are sent in different RTP packets with the same sequence number and timestamp.

15. The method of claim 1, wherein the first node combines the functions of convergence and scheduling, wherein the scheduling operation is chosen to take into account the link quality, the level of traffic being served, or a combination of the two.

16. The method of claim 1, wherein the multiple versions of a multimedia packet are sent in different RTP packets with different contributing source information.

17. The method of claim 16, wherein the first node uses the contributing source information to identify different versions of the same multimedia packet, and chooses one version to send to the second node.

18. The method of claim 16, for use in a multimedia conference call;

wherein different physical sources use different sets of contributing source information values to identify multiple versions of multimedia packets corresponding to respective physical sources.

19. A method of enabling mobile-to-mobile multimedia calls in a wireless Internet Protocol (IP) network, comprising the steps of:

sending a single version of a multimedia packet from a first mobile station to a first base station;

sending the multimedia packet from the first base station to a media gateway;

generating multiple versions of the multimedia packet at the media gateway;

sending at least one of the multiple versions to a second base station; and

selecting, by the second base station, the appropriate version from the at least one of the multiple versions to send to a second mobile station.

20. A signaling method in a wireless Internet Protocol (IP) network, comprising the steps of:

informing, using a SIP•

INFO message, a call processing or call control function that specialized treatment of a source is desired before transmission over the air, wherein the call-control function activates a packet filter function in the radio network.

21. The method of claim 20, wherein the activation of the packet filter function involves changing the classifier rule at the MAC Layer that activates a specialized packet processing function for specific multiple-description formals.

22. A server adapted to deliver multimedia packets over a wireless internet protocol (IP) network, comprising:

means for generating multiple versions of a multimedia packet;

means for sending, to a base station, at least one of the multiple versions of the multimedia packet in individual real time protocol (RTP) packets with the same time-stamp information, or

means for sending, to a base station, at least one of the multiple versions of the multimedia packet in a single real time protocol (RTP) packet with multiple sub-packets identified with a timestamp offset set to zero.

23. A base station comprising:

a packet filter adapted to examine each incoming RTP packet;

means for identifying that multiple RTP packets correspond to the same multimedia packet;

or means for identifying multiple versions of the multimedia packet in the same RTP packet; and

means for selecting, based on the radio channel and traffic characteristics, an appropriate source format of the RTP packet to send to a mobile station.

24. The base station of claim 23, wherein the means used for identifying that multiple RTP packets correspond to the same multimedia packet comprises means for identifying different contributing source information for the RTP packets, wherein a set of source information corresponding to the multimedia packets has been conveyed to the base station using a signaling procedure.

25. A media gateway, comprising:

means of receiving a single multimedia description and converting it to multiple descriptions,

means to encapsulate the multiple descriptions in multiple RTP packets, wherein the RTP packets have one of the following characteristics;

the same timestamp and sequence number;

or the same timestamp information but different contributing source information, or

means to assemble the multiple descriptions in a single RTP packet with subheaders used to identify the different descriptions, wherein the subheaders used are timestamp offsets.