# US 2014/0153654 A1 · Joint Source-Channel Decoding with Source Sequence Augmentation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0153654 A1 - Document ID: US20140153654A1 - Status: Published application - Kind: A1 - Application number: 13/693,031 - Filed: 2012-12-03 - Published: 2014-06-05 - Earliest claimed: 2012-12-03 - Assignees: Digital PowerRadio, LLC - Applicants: Digital Powerradio, LLC - Inventors: Branimir R. Vojcic; Ivan V. Bajic; Javad Haghighat - Web page: https://patentgrep.com/patent/US20140153654A1 ## CPC - H04N 21/2383: Channel coding {or modulation} of digital bit-stream, e.g. QPSK modulation (arrangements for detecting or preventing errors in the information received by adapting the channel coding H04L1/0009; analogue front ends or means for connecting modulators, demodulators or transceivers to a transmission line H04L27/0002) - H04N 19/65: using error resilience - H04N 21/4382: {Demodulation or channel decoding, e.g. QPSK demodulation (analog front ends or means for connecting modulators, demodulators or transceivers to a transmission line H04L27/0002)} - H04N 21/631: {Multimode Transmission, e.g. transmitting basic layers and enhancement layers of the content over different transmission paths or transmitting with different error corrections, different keys or with different transmission protocols} - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract Methods and systems for augmenting a source message by suitably-chosen bits and/or sequences of bits for the purpose of enhancing decoding or synchronization performance. Properties of the source message can be used to select and optimize synchronization sequences, including their length and placement within the source message. Various message attributes, such as message or segment weight, symbol counts, and others, including their combinations, may be encoded into the synchronization sequence to further improve decoding performance in the presence of errors. These methods and systems can be employed for standalone source decoding of noisy bit streams, as well as iterative joint source-channel decoding. They may further be combined with other methods whether or not known in the art, such as CRC and forward error correction, to achieve the desired performance complexity trade-off. ## Claims ### Claim 1 A system for augmenting a source message bit sequence with a synchronization sequence to facilitate better source decoding, the system comprising: a source encoder for inserting at least one synchronization sequence to the source message bit sequence to create an encoded source message bit sequence and for jointly decoding the encoded source message bit sequence, wherein the decoding of the encoded source message bit sequence is based on the at least one synchronization sequence, the at least one synchronization sequence being selected from a set of at least two defined synchronization sequences, the selection based on one or more characteristics of the source message bit sequence, said characteristics being selected from the group consisting of a sequence weight, weight modulo-q and other source sequence specific attributes which are based on at least one of a frequency and value of at least one symbol in the source message bit sequence. ### Claim 2 (depends on 1) The system of claim 1 wherein the defined synchronization sequences are selected to minimize the bit-error-rate or packet-error-rate performance of source decoding. ### Claim 3 (depends on 1) The system of claim 1 wherein the defined synchronization sequences are selected to maximize Hamming distances between synchronization sequences in the set. ### Claim 4 (depends on 3) The system of claim 3 wherein the defined synchronization sequences are also selected to have low autocorrelation function sidelobes. ### Claim 5 A method for augmenting a source message bit sequence with two or more synchronization sequences placed at different bit positions within the source message in order to facilitate better source decoding, the method comprising: a. placing each one of said two or more synchronization sequences at a different bit position within the source message bit sequence wherein said two or more synchronization sequences are for jointly decoding the encoded source message bit sequence, and said two or more synchronization sequences are selected from a plurality of sets of defined synchronization sequences, each set corresponding to said different bit positions within the source message, wherein the size of each said set is at least M≧1 and at least one said set is of size M≧2; b. for each source message, selecting a specific synchronization sequence from said plurality of sets, wherein each set has M available synchronization sequences for a specific position, wherein the selection of said specific synchronization sequence is based on one or more characteristics of a source sequence such as sequence weight, weight modulo-q and other source sequence specific attributes which are based on at least one of a frequency and value of at least one symbol in the source message bit sequence; c. inserting each said selected specific synchronization sequence at said specific position. ### Claim 6 (depends on 5) The method of claim 5 wherein the synchronization sequences are selected to minimize the bit-error-rate or packet-error-rate performance of source decoding. ### Claim 7 (depends on 5) The method of claim 5 wherein said two or more synchronization sequences are selected to maximize the Hamming distance among each other, and minimize the autocorrelation sidelobes for a given sequence length. ### Claim 8 (depends on 5) The method of claim 5 wherein the other source sequence specific attributes are based on linear and nonlinear combinations of the frequencies and values of the symbols in the source message bit sequence. ### Claim 9 A method for augmenting segments of a source message bit sequence with additional bits in order to facilitate better source decoding, wherein the segments may include one or more symbols, groups of symbols, fields and groups of fields, the method comprising: a. selecting a segment of a source message bit sequence to augment; and b. inserting one or more synchronization sequence bits in, or appending said one or more synchronization sequence bits to, one of the selected segments to maximize the distance of the segment values or to minimize the probability of erroneous decoding of the segment, wherein said one or more synchronization sequence bits are for jointly decoding the selected segment, and wherein the step of selecting a segment for augmentation is based on one or more of the following criteria: i. said selected segment is important for decoding the source message bit sequence; ii. said selected segment is important for decoding or interpreting other segments in the source message bit sequence; iii. said selected segment occurs more frequently than other segments; and iv. said selected segment is prone to decoding errors. ### Claim 10 A method for encoding of a source packet for unequal error protection of selected parts of the source packet which consists of multiple fields of source bits, the method comprising: a. partitioning the source packet into two or more subpackets, wherein each subpacket comprises one or more source encoded fields, and wherein each subpacket has a different level of error protection; b. for one or more of said subpackets containing one or more source encoded fields, encoding selectively at a transmitter said one or more subpackets with a code for resolving errors to provide additional error protection for more reliable decoding of said one or more subpackets in order to achieve a desired level of performance after decoding; and c. encoding each subpacket with a CRC code to produce a CRC bit sequence to facilitate separate error concealment of said two or more subpackets in a decoder, wherein the length of different CRC bit sequences may be different depending at least in part on one or more of the subpacket length and the desired level of required error protection, wherein said code for resolving errors and said CRC code facilitate resolving errors during joint decoding of each subpacket at a receiver. ### Claim 11 (depends on 10) The method of claim 10 wherein said code for resolving errors in said joint decoding to provide additional error protection includes a forward error correction code. ### Claim 12 (depends on 10) The method of claim 10 wherein said code for resolving errors in said joint decoding to provide additional error protection includes a single parity check code. ### Claim 13 (depends on 10) The method of claim 10 wherein said code for resolving errors in said joint decoding to provide additional error protection includes augmenting the source bits of the source packet with one or more synchronization sequences. ### Claim 14 (depends on 10) The method of claim 10 wherein the performance of the source decoding is measured in terms of perceptual quality.