Redinbo Mobile cellular communication systems, a rapidly growing communications medium, rely upon significant digital processing elements, particularly in the central cell sites where numerous users in a geographic area interface with the full network. Reliability is a serious design requirement where processing elements are shared among many users and failures can significantly degrade the network performance for all users. This research is applying new evolving fault tolerance design methodologies to modern system designs which employ configurations of high-speed functional processing units, Application-Specific Integrated Circuits (ASICs). In the new fault-tolerance design philosophy, algorithm- based fault tolerance, data sample integrity is paramount, and special number codes are being used to generate parity values in parallel with the normal processing operations. Comparisons between these values and other associated parity generation are very similar to functional elements employed in the main processing operations, and therefore can be substituted for failed functional elements when failures are detected. The important interrelationships between detecting failed functional units and protecting the underlying control units are being examined. Simple reliability calculations employing straightforward failure rate models are being used to guide fault tolerance levels and the system location for detection facilities.
