EFFECT OF FREQUENCY SCALING ON POWER CONSUMPTION IN EMBEDDED SYSTEMS (original) (raw)
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Embedded systems are at the core of many new emerging technologies and applications, deeply integrated into our daily lives. Especially, the demand for battery-powered solutions in consumer-related applications is growing, to support different environments and fields of application. Therefore, energy efficiency measures for embedded systems become even more important. In this paper, a dynamic frequency scaling approach for embedded systems is presented to reduce the overall energy consumption while still meeting time constraints within a real-time operating system. Starting with a general discussion and mathematical derivation along with an elaboration of the state of the art, our concept and implementation is discussed. This includes primarily the developed Worst-Case Execution Time (WCET) aware Earliest Deadline First (EDF) scheduler which is used to dynamically scale the frequency at runtime. Moreover, a use case targeting a real-time smart home application is provided, which was...
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