TY - CONF AB - Faced with increasing demands on energy efficiency, current electronic systems operate according to complex power management schemes including more and more fine-grained voltage frequency scaling and power shutdown scenarios. Consequently, validation of the power design intent should begin as early as possible at electronic system-level (ESL) together with first executable system specifications for integrity tests. However, today's system-level design methodologies usually focus on the abstraction of digital logic and time, so that typical low-power aspects cannot be considered so far. In this paper, we present a high-level modeling approach on top of the SystemC/TLM standard to simulate power distribution and voltage based implications in a "loosely-timed" functional execution context. The approach reuses legacy TLM models and prevents the need for detailed lock-step process synchronization in contrast to existing methods. A case study derived from an open source low-power design demonstrates the efficiency of our approach in terms of simulation performance and testability. AU - Mischkalla, Fabian AU - Müller, Wolfgang ID - 36919 KW - Time-varying systems KW - Time-domain analysis KW - Synchronization KW - Context modeling KW - Clocks KW - Semantics KW - Standards TI - Efficient Power-Intent Validation Using "Loosely-Timed" Simulation Models: A Non-Invasive Approach ER - TY - CONF AB - In this paper we present a combined hardware/software approach for synchronizing the sampling clocks of an acoustic sensor network. A first clock frequency offset estimate is obtained by a time stamp exchange protocol with a low data rate and computational requirements. The estimate is then postprocessed by a Kalman filter which exploits the specific properties of the statistics of the frequency offset estimation error. In long term experiments the deviation between the sampling oscillators of two sensor nodes never exceeded half a sample with a wired and with a wireless link between the nodes. The achieved precision enables the estimation of time difference of arrival values across different hardware devices without sharing a common sampling hardware. AU - Schmalenstroeer, Joerg AU - Haeb-Umbach, Reinhold ID - 11891 KW - synchronization KW - acoustic sensor network T2 - 21th European Signal Processing Conference (EUSIPCO 2013) TI - Sampling Rate Synchronisation in Acoustic Sensor Networks with a Pre-Trained Clock Skew Error Model ER -