A trellis is a

graph Graph may refer to: Mathematics *Graph (discrete mathematics), a structure made of vertices and edges **Graph theory, the study of such graphs and their properties *Graph (topology), a topological space resembling a graph in the sense of discre ...

whose nodes are ordered into vertical slices (''time'') with each node at each time connected to at least one node at an earlier and at least one node at a later time. The earliest and latest times in the trellis have only one node. Trellises are used in encoders and decoders for

communication theory Communication theory is a proposed description of communication phenomena, the relationships among them, a storyline describing these relationships, and an argument for these three elements. Communication theory provides a way of talking about a ...

and

encryption In cryptography, encryption is the process of encoding information. This process converts the original representation of the information, known as plaintext, into an alternative form known as ciphertext. Ideally, only authorized parties can dec ...

. They are also the central datatype used in Baum–Welch algorithm or the

Viterbi Algorithm 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 ...

Ryan, M. S., & Nudd, G. R. (1993). The viterbi algorithm. University of Warwick, Department of Computer Science. for Hidden Markov Models. The trellis graph is named for its similar appearance to an architectural trellis.

References

See also