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...rks to support themselves by harvesting energy from the environment. For instance, by converting mechanical vibration into energy [1], by using solar panels [2], by utilizing thermoeletric generators =-=[3]-=-, or by converting ambient radio power into energy [4]. Such harvesting methods are also referred to as “recycling” energy [5]. This energy harvesting ability is crucial for many network design proble...

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...version has the advantage that it generates the desired voltage directly, without need for a separate voltage source. However, piezoelectric materials are breakable and can suffer from charge leakage =-=[33,36,37]-=-. Examples of piezoelectric energy harvesters can be found in references 38–42 and references therein. The principle of electrostatic energy harvesting is based on changing the capacitance of a vibrat...

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....2013.2283071 is often of prohibitive complexity, if not impossible. Therefore, sensors that harvest energy from the environment, e.g., in the form of solar, thermal, vibrational or radio energy [2], =-=[3]-=-, have been proposed and are now commercially available. Given the interest outlined above, the problem of designing optimal transmission protocols for energy-harvesting wireless sensor networks has r...

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...n part by the UK EPSRC (grant EP/K033166/1) and the EU (project IoT@Work FP7-257367). D. Buranapanichkit was supported by a Royal Thai Government Scholarship (Science and Technology). harvesting [3], =-=[4]-=-, [5], or strive for more efficient scheduling and transmission protocols [6], [7], [8], [9], [10]. These try to bridge the gap between data sensing and transmission requirements and the corresponding...

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...m thesenvironment using small scale transducers. The harvestedsenergy is used in order to feed low power circuits such assWireless Sensor Nodes (WSNs). There are various sources forsenergy harvesting =-=[1]-=-: solar, organic, vibration, thermal, nearfield electromagnetic and far-field electromagnetic (or RadioFrequency RF). Most energy harvesting transducers deliver asvery low voltage (below 1V) and a ver...

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...ries severely limits the achievable performance level of application scenarios with increased energy demands, e.g., [2]. Ambient energy harvesting, particularly in the form of solar energy harvesting =-=[3, 4]-=-, has thus attracted much attention as a promising solution for enabling perpetual system operation. The ultimate goal of an energy harvesting system is to enable uninterrupted longterm (i.e., on the ...

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...nerators is proportional to the cube of the vibration frequency and drops dramatically at low frequencies (1–100Hz) [27, 28]. Because the main frequencies in the environment are relatively low, the mechanical energy harvester may need to utilize the upconverter to transform the low frequency into high frequency to achieve an increased power output [27, 28]. Among the three mechanical energy harvesting methods, the piezoelectric and electrostatic harvesters have the ability to generate voltage ranging from 2 to 10V, but the electromagnetic harvesters can only produce a maximum voltage of 0.1 V [41]. The external excitations are random for vibration energy harvesting systems, so it is hoped that the systems are able to have a better response towards vibration excitations with different frequencies and amplitudes in order to ensure the energy harvesting efficiency. So it is necessary to comprehensively consider two factors including system output power and bandwidth of the resonant region and select the appropriate system parameters when the system damping ratio is designed. In order to maximize the generated energy, the below basic principles should be followed during the design of vibra...

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...antaneous power falls within a wide range. In fact, sparse energy sources are present in a wide variety of physical phenomena. Among others, acoustic energy, mechanical, vibrational or RF energy [6], =-=[7]-=-, [8] are considered representative examples of such sources, when considering a large time scale. In this work, we propose the power crest factor as a metric to enable the comparison of performance a...

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... demonstrate that the energy leakage of state of art energy management policies can be avoided by jointly controlling the source and channel coding rates. I. INTRODUCTION Energy harvesting techniques =-=[1]-=- enable the design of completely autonomous wireless sensor networks (WSN). However, fluctuations in the amount of the energy being harvested call for resource management policies that achieve a trade...

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...ffectiveness (see [31] and references therein). Jamming constitutes a form of denial-of-service attack that is particularly devastating given that WSN devices, including proposed future architectures =-=[2, 8]-=-, are severely energy constrained. Therefore, the prospects for achieving communication seem dire given an attacker who controls a large number of network devices and coordinates their combined resour...