A switched control scheme to handle quantisation in the design of high-precision computing system components

Abstract

Over the last years, several problems related to computing systems are being re-considered with a control-centric approach, leading to a system-theoretical component design and assessment, [2, 4]. Notable examples are thread scheduling [3], memory management [7], and time synchronisation [1]. When addressed as control ones, many of said problems reveal a surprisingly similar structure, where the dynamics to be controlled is very simple, and the only source of uncertainty are exogenous disturbances caused by the external environment, other components of the computing system, or any combination thereof. Whenever the quantised nature of controls and measurements is negligible, standard control structures can be devised to compensate for disturbances. However, in high-precision applications, quantisation may become so relevant to cause undesired fluctuations in the controlled variables, and the same structures may not be adequate anymore. Starting from time synchronisation in Wireless Sensor Networks (WSN), a general technique is proposed to solve this issue.