Viterbi decoder

For binary SCS, yn < A/2, where yn should be close to zero if dn =0 was transmitted, and close to A/2 for dn = 1. Second, depending on the type of error correction encoding of d, soft-input decoding algorithms, e g. a Viterbi decoder for convolutional codes, can be used to decode from y the most likely transmitted watermark message m. 

Finally, a soft error correction decoding algorithm, e.g., a Viterbi decoder, is used to compute for / = 0,..., - 1, the most likely watennark message u from the prob-... 

We modify the DLX [9] and PicoJava II [10] Instruction Set Architecture (ISA) by adding new custom permutation instruction WUHPERM [11] in their instruction set. The performance of the new instruction is analyzed for execution time. We design and implement the new permutation insfruction in CPUSIM 3.6.8 [12] and Mic-1 simulator [10], respectively. Similarly, by using the same approach of designing custom instructions, the ISA of DLX processor is enhanced by adding Texpand instruction, used in Viterbi decoding algorithm. We test the implementation and performance of this new instruction on the CPUSIM 3.6.8 simulator. 

We describe the Viterbi decoding technique used for convolutional codes. The application of convolutional encoding in combination with Viterbi decoding is suitable for channels with Additive White Gaussian Noise (AWGN). The Viterbi decoding method was first introduced by the founder of Qualcomm Corporation,... 

Concatenated Reed—Solomon and convolution (Viterbi decoding) 6.5-7.5 8.5-9.5 Moderate... 

A. J. Viterbi (1967) Error bounds for convolutional codes and an asymptotically optimum decoding algorithm. IEEE Trans. Informat. Theory IT-13, pp. 260-269... 

Andrew J. Viterbi [8]. After the introduction of Viterbi algorithm, many scientists and researchers extended this work by varying and improving the decoder design parameters in order to enhance the performance in software and hardware implementations. 

Table 4.8 shows the comparison of the performance of Viterbi algorithm, in particular, trellis expansion function, when implemented in DUX assembly language and with custom Texpand instruction. This instruction is called nineteen times in the Viterbi algorithm for 6-bit decoding. The results show substantial improvement of three times when trellis expands function is implemented as a custom instruction. 

To decode the TCM signal, the received signal plus noise in each signaling interval is correlated with each possible signal/code combination a search for the closest symbol combination is made by means of a Viterbi algorithm using the sums of these correlations as the metric in the algorithm (i.e.. Euclidian... 

Viterbi algorithm An efficient algorithm for decoding convolutional codes, among other applications, that implements maximum likelihood estimation. 

Viterbi algorithm An efficient method for decoding convolutional codes based on finding the path on a treUis diagram that is at minimum distance from the received sequence. 

Shannon, C.E. 1948. A mathematical theory of communication. Bell Sys. Tech.. 27 379 423, 623 656. Ungerboeck, G. 1982. Channel coding with multilevel/phase signals. IEEE Trans. Inf Theory (Jan.). Viterbi, A.J. 1967. Error bounds for convolutional codes and an asymptotically optimum decoding algorithm. IEEE Transactions on Information Theory IT-13 260-269. 

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