Asynchronous real-time coders in the discrete control environment: Generative models for input/output spaces

A key element in the theory of discrete-control of continuous-state systems is the coder -- the hybrid interface between the continuous-valued part of the system (the plant) and the discrete (finite) part of the system (the controller). The study of such coders, particularly in the context of asynchronous controller design, raises certain profound theoretical questions. These are often masked in the traditional synchronous models that have been studied, but rear their heads quite vividly when time is no longer implicit and regular, but explicitly arises asynchronously as various "events" in the system environment occur. This paper is concerned with these issues and with system models designed to resolve them.