A A* heuristic search strategy with two-level tree beam search

This paper presents an A* heuristic search strategy with two-level tree beam search for large vocabulary continuous speech recognition. The sets of all possible syllable sequences and the set of all possible word sequences are organized into a syllable-level tree and a word-level tree. All best backward paths ending at each node in the word-level tree are kept in order to explore multi-syllable words, and a backtracking search is conducted to do this