What is the Viterbi algorithm used for?
The Viterbi algorithm is a dynamic programming algorithm for obtaining the maximum a posteriori probability estimate of the most likely sequence of hidden states—called the Viterbi path—that results in a sequence of observed events, especially in the context of Markov information sources and hidden Markov models (HMM).
What is trellis decoding?
Trellis decoding is a popular method to recover encoded information corrupted during transmission over a noisy channel.
What is Viterbi path?
The Viterbi path is an estimate of the underlying state path in hidden Markov models (HMMs), which has a maximum joint posterior probability. Hence it is also called the maximum a posteriori (MAP) path. For an HMM with given parameters, the Viterbi path can be easily found with the Viterbi algorithm.
What is Viterbi decoding in communication engineering?
A Viterbi decoder uses the Viterbi algorithm for decoding a bitstream that has been encoded using a convolutional code or trellis code. It is most often used for decoding convolutional codes with constraint lengths k≤3, but values up to k=15 are used in practice.
What is meant by Viterbi decoding?
What is the Viterbi path?
What is Viterbi trellis?
The best known and most commonly used trellis-based decoding algorithm is the Viterbi algorithm [23, 79, 105]. It is a maximum likelihood decoding algorithm. Convolutional codes with the Viterbi decoding have been widely used for error control in digital communications over the last two decades.
What is Viterbi receiver?
What is the constraint length for Viterbi decoder?
It is most often used for decoding convolutional codes with constraint lengths k≤3, but values up to k=15 are used in practice. Viterbi decoding was developed by Andrew J. Viterbi and published in the paper Viterbi, A. (April 1967). “Error Bounds for Convolutional Codes and an Asymptotically Optimum Decoding Algorithm”.
How is a convolutional code decoded in Viterbi?
VITERBI DECODING OF CONVOLUTIONAL CODES depend only on the constraint length of the code and not on the parity functions. Figure 9- 2 shows the predecessor states for each state (the other end of each arrow). For instance, for state 00, α = 00 and β = 01; for state 01, α = 10 and β = 11.
Which is the branch metric for Viterbi decoding?
THE VITERBI DECODER3 Figure 9-2: The branch metric for hard decision decoding. In this example, the receiver gets the parity bits 00. Figure 9-2, where the received bits are 00. For each state transition, the number on the arc showsthebranchmetricforthattransition.
How is the Viterbi decoder used in MATLAB?
The Viterbi Decoder block decodes input symbols to produce binary output symbols. This block can process several symbols at a time for faster performance. This block can output sequences that vary in length during simulation.