Complete user datagram protocol (CUDP) for wireless multimedia packet networks using improved packet level forward error correction (FEC) coding

Abstract

A complete User Datagram Protocol (CUDP) is disclosed that reduces packet loss. Channel frame error information is used with a packet level forward error correction (FEC) coding technique to accommodate wireless multimedia traffic. Each packet, as well as the channel frame error information, is forwarded to a given application. The CUDP protocol further assists the FEC decoding process by forwarding the locations of corrupted frames to the FEC decoder. Maximal Distance Separable (MDS) codes can be applied to a group of packets, to achieve additional robustness. An MDS decoder utilizes the frame error information to recognize the erasures within each packet. The error information can be represented as a set of LTU error indicators associated with each packet (for FEC decoders requiring an erasure indicator). The error indicators point to the starting and ending location of the erroneous data. The error information can also be represented as a reformatted packet (for FEC decoders Recognizing Erasures). The frame (LTU) error information from the lower layers is incorporated in the packet payload. An FEC encoder is also disclosed that encodes multimedia packets utilizing a packet-coding scheme, such as a Vertical Packet Coding (VPC) scheme or a Long Vertical Packet Coding (LVPC) scheme.

1 . A method for transmitting a multimedia packet from a wireless packet network to a wired network conforming to the Internet Protocol (IP), said multimedia packets encoded using a forward error correction (FEC) coding technique, said method comprising the steps of: 
 embedding frame error information in said multimedia packet;    forwarding said multimedia packet to a receiver on said wired network; and    discarding a multimedia packet having an unrecoverable frame error.    
   
   
       2 . The method of  claim 1 , wherein said forward error correction coding technique employs Maximal Distance Separable codes that are applied to a number, k, of information packets comprised of X data units, and wherein up to X codewords are formed of length n using one data unit from each of said k information packets.  
   
   
       3 . The method of  claim 1 , wherein said forward error correction coding technique employs Maximal Distance Separable codes that are applied to a number, k, of information packets comprised of X data units, and wherein up to X/L codewords of length nL are formed using L data units from each of said k information packets.  
   
   
       4 . The method of  claim 1 , wherein said forward error correction coding technique employs Maximal Distance Separable (MDS) codes that are applied to each of said information packets comprised of X data units to create k information packets comprised of X′ data units, and a second set of said MDS codes are applied to of said information packets comprised of X′ data units, and wherein up to X′ codewords are formed using one data unit from each of said k information packets.  
   
   
       5 . A method for transmitting a multimedia packet from a wireless packet network to a wired network conforming to the Internet Protocol (IP), said multimedia packets encoded using a forward error correction (FEC) coding technique, said method comprising the steps of: 
 decoding said multimedia packet using frame error information;    forwarding said multimedia packet to a receiver on said wired network; and    discarding a multimedia packet having an unrecoverable frame error.    
   
   
       6 . The method of  claim 5 , wherein said forward error correction coding technique employs Maximal Distance Separable codes that are applied to a number, k, of information packets comprised of X data units, and wherein up to X codewords are formed of length n using one data unit from each of said k information packets.  
   
   
       7 . The method of  claim 5 , wherein said forward error correction coding technique employs Maximal Distance Separable codes that are applied to a number, k, of information packets comprised of X data units, and wherein up to X/L codewords of length nL are formed using L data units from each of said k information packets.  
   
   
       8 . The method of  claim 5 , wherein said forward error correction (FEC) coding technique employs Maximal Distance Separable (MDS) codes that are applied to each of said information packets comprised of X data units to create k information packets comprised of X′ data units, and a second set of said MDS codes are applied to of said information packets comprised of X′ data units, and wherein up to X′ codewords are formed using one data unit from each of said k information packets.  
   
   
       9 . A system for transmitting a multimedia packet from a wireless packet network to a wired network conforming to the Internet Protocol (IP), said multimedia packets encoded using a forward error correction (FEC) coding technique, comprising: 
 a memory for storing computer readable code; and    a processor operatively coupled to said memory, said processor configured to:    embed frame error information in said multimedia packet;    forward said multimedia packet to a receiver on said wired network; and    discard a multimedia packet having an unrecoverable frame error.    
   
   
       10 . The system of  claim 9 , wherein said forward error correction coding technique employs Maximal Distance Separable codes that are applied to a number, k, of information packets comprised of X data units, and wherein up to X codewords are formed of length n using one data unit from each of said k information packets.  
   
   
       11 . The system of  claim 9 , wherein said forward error correction coding technique employs Maximal Distance Separable codes that are applied to a number, k, of information packets comprised of X data units, and wherein up to X/L codewords of length nL are formed using L data units from each of said k information packets.  
   
   
       12 . The system of  claim 9 , wherein said forward error correction coding technique employs Maximal Distance Separable (MDS) codes that are applied to each of said information packets comprised of X data units to create k information packets comprised of X′ data units, and a second set of said MDS codes are applied to of said information packets comprised of X′ data units, and wherein up to X′ codewords are formed using one data unit from each of said k information packets.  
   
   
       13 . A system for transmitting a multimedia packet from a wireless packet network to a wired network conforming to the Internet Protocol (IP), said multimedia packets encoded using a forward error correction (FEC) coding technique, comprising: 
 a memory for storing computer readable code; and    a processor operatively coupled to said memory, said processor configured to:    decode said multimedia packet using frame error information;    forward said multimedia packet to a receiver on said wired network; and    discard a multimedia packet having an unrecoverable frame error.    
   
   
       14 . The system of  claim 13 , wherein said forward error correction coding technique employs Maximal Distance Separable codes that are applied to a number, k, of information packets comprised of X data units, and wherein up to X codewords are formed of length n using one data unit from each of said k information packets.  
   
   
       15 . The system of  claim 13 , wherein said forward error correction coding technique employs Maximal Distance Separable codes that are applied to a number, k, of information packets comprised of X data units, and wherein up to X/L codewords of length nL are formed using L data units from each of said k information packets.  
   
   
       16 . The system of  claim 13 , wherein said forward error correction coding technique employs Maximal Distance Separable (MDS) codes that are applied to each of said information packets comprised of X data units to create k information packets comprised of X′ data units, and a second set of said MDS codes are applied to of said information packets comprised of X′ data units, and wherein up to X′ codewords are formed using one data unit from each of said k information packets.