FILTER AUTOMATA AND PRR FILTERING

摘要

Parity rule recursive (PRR) filtering was defined by Steiglitz and others and shown to support certain moving periodic strings (called particles) with soliton-like properties. Particles are easily recognized on space-time diagrams. Later, some meaningful computations were shown to be performed by colliding particles. The aim of this paper is to introduce the family of filter automata (FA) and to show that they constitute a generalization of PRR filtering. We define FA by applying the notions of an activating function, a program, and a reset function. These facilitate the description of transmitting media by a pipeline of FA, that is by a one-way linear cellular automaton. Our family of FA supports not only particles of PRR filtering but also other types of periodic and non-periodic strings. For example, contrary to PRR filtering, the FA support annihilation and strange particles. We give some examples of FA behaviour.