Operational characteristics of a harware-based pattern matcher

The design and operation of a new class of hardware-based pattern matchers, such as would be used in a backended database processor in a full-text or other retrieval system, is presented. This recognizer is based on a unique implementation technique for finite state automata consisting of partitioning the state table among a number of simple digital machines. It avoids the problems generally associated with implementing finite state machines, such as large state table memories, complex control mechanisms, and state encodings. Because it consists primarily of memory, with its high regularity and density, needs only limited static interconnections, and operates at a relatively low speed, it can be easily constructed using integrated circuit techniques. After a brief discussion of other pattern-matching hardware, the structure and operation of the partitioned finite state automaton is given, along with a simplified discussion of how the state tables are partitioned. The expected performance of the resulting system and the state table partitioning programs is then discussed.