Abstract -Battery powered wireless sensor nodes are used in many applications. They can be placed in remote locations and can operate for a long period of time without the need for maintenance. However, finite battery lifetime is one of the main limitations of such devices. Energy harvesting can be used to recharge batteries from environmental energy sources. This enables continuous work when energy neutrality is satisfied. For optimal use of available energy, when energy harvesting is used, the optimization goal switches from energy management to workload maximization while maintaining energy neutrality. In order to achieve energy neutrality, prediction of energy that can be harvested in the future is needed. This prediction can be based on previous measured data. However, this approach can be unreliable when weather conditions change during the day or between days. To improve prediction precision, weather forecast can be used. This information has been used to predict energy that can be harvested in the future but only for the next few hours. We present a twolevel predictor that uses cloud cover information from hourly weather forecast for next 24 hour period to predict energy that can be harvested in the same time interval. Proposed predictor achieves a 26% less prediction mean absolute percentage error, a 15% less mean absolute deviation percent error and allows an 8% better performance of simulated wireless sensor node compared to Exponentially Weighted Moving Average (EWMA) predictor.
Satellite backbone networks provide a viable means of establishing broadband connectivity for remote, sparsely populated areas. In addition, satellite communication systems are well suited for airborne, maritime, and disaster relief environments. Technologies for links are continuing to improve in performance and power efficiency, making onboard regeneration and routing feasible within spacecraft power envelope. In this article, we implement and analyze a spaceborne router design integrated on a field-programmable gate array (FPGA). FPGA provides a flexibility needed to circumvent space radiation effects on chip circuitry, as they can be reconfigured at runtime. We explored scalability of the high-end state-of-the art FPGA chip family, and its ability to support high bit-rate satellite links: 10 Gbps satellite-to-ground links and 100 Gbps intersatellite links. Through implementation and testing, we confirm that the current FPGA technology can support space routers with very high data throughput.
Energy harvesting wireless sensor nodes are interesting for the Internet of Things, since they can provide continuous operation by adapting workload not only to the current energy reserves, but to the amount of energy that can be harvested in the future also. We present a multistage day ahead hourly solar energy prediction algorithm. The predictor uses cloud cover and precipitation probability predictions from weather forecast obtained once per day for 24 hours in advance. To compensate for short-term weather changes until the next weather forecast data is obtained, forecast errors of humidity and atmospheric pressure are fed to the fuzzy logic filter. The filter adjusts predictions of cloud cover and precipitation probability, which are applied to the clear-sky radiation model in order to obtain prediction of solar energy. The prediction of solar energy is additionally corrected based on the energy prediction error in the preceding time slot. The results show that the proposed predictor outperforms the state-of-the-art predictors in terms of prediction error. Proposed predictor and state-of-the-art predictors were also evaluated using a simulated wireless sensor node with the simple energy management algorithm, where the proposed predictor was the most efficient at maintaining energy neutrality.
-Microcontrollers are often used as central processing elements in embedded systems. Because of different sleep and performance modes that microcontrollers support, their power consumption may have a high dynamic range, over 100 dB. In this paper, a data acquisition (DAQ) system for measuring and analyzing the power consumption of microcontrollers is presented. DAQ system consists of a current measurement circuit using potentiostat technique, a DAQ device based on system on chip PSoC 5LP and Python PC program for the analysis, storage and visualization of measured data. Both Successive Approximation Register (SAR) and Delta-Sigma (DS) ADCs contained in the PSoC 5LP are used for measuring voltage drop across the shunt resistor. SAR ADC samples data at a 10 times higher rate than DS ADC, so the input range of DS ADC can be adjusted based on data measured by SAR ADC, thus enabling the extension of current measuring range by 28%. Implemented DAQ device is connected with a computer through a USB port and tested with developed Python PC program.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.