Search results for "Wire"
showing 10 items of 1383 documents
An On-Demand Energy Requesting Scheme for Wireless Energy Harvesting Powered IoT Networks
2018
Energy harvesting (EH) delivers a unique technique for replenishing batteries in Internet of Things (IoT) devices. Equipped with an energy harvesting accessory, EH-enabled sensor nodes/IoT devices ...
Reducing Overhearing Energy in Wake-Up Radio-Enabled WPANs: Scheme and Performance
2018
Wake-up Radio (WuR)-enabled wireless personal area networks (WPANs) are more popular over conventional WPANs thanks to WuR's on-demand transmission feature and overwhelming energy consumption superiority. In a WuRenabled WPAN, overhearing occurs when a wake-up receiver decodes and validates the address of a wake-up call which is not intended to it. However, such overhearing consumes a portion of the required reception energy for unintended nodes. To diminish overhearing thus conserve total reception energy in a network, we propose a bit-by-bit address decoding (BBAD) scheme and compare it with another addressing scheme for WuR that uses a micro-controller unit to decode and match the whole …
Efficient and Lightweight Data Integrity Check in In-Networking Storage Wireless Sensor Networks
2009
In In-networking storage Wireless Sensor Networks, sensed data are stored locally for a long term and retrieved on-demand instead of real-time. To maximize data survival, the sensed data are normally distributively stored at multiple nearby nodes. It arises a problem that how to check and grantee data integrity of distributed data storage in the context of resource constraints. In this paper, a technique called Two Granularity Linear Code (TGLC) that consists of Intra-codes and Inter-codes is presented. An efficient and lightweight data integrity check scheme based on TGLC is proposed. Data integrity can be checked by any one who holds short Inter-codes, and the checking credentials is shor…
Optimal Buffer Resource Allocation in Wireless Caching Networks
2019
Wireless caching systems have been exhaustively investigated in recent years. Due to limited buffer capacity, and unbalanced arrival and service rates, the backlogs may exist in the caching node and even cause buffer overflow. In this paper, we first investigate the relationship among backlogs, buffer capacity, data arrival rate and service rate, utilizing the martingale theory which is flexible in handling any arrival and service processes. Then given a target buffer overflow probability, the minimal required buffer portion is determined. If the devoted buffer capacity can fulfill all serving users' minimal buffer requirements, an optimization problem is constructed with the objective to m…
A symbolic distributed event detection scheme for Wireless Sensor Networks
2016
Due to the possibility of extensive and pervasive deployment of many tiny sensor devices in the area of interest, Wireless Sensor Networks (WSNs) result particularly suitable to detect significant events and to react accordingly in industrial and home scenarios. In this context, fuzzy inference systems for event detection in WSNs have proved to be accurate enough in treating imprecise sensory readings to decrease the number of false alarms. Besides reacting to event occurrences, the whole network may infer more information to enrich the event semantics resulting from reasoning processes carried out on the individual nodes. Contextual knowledge, including spatial and temporal relationships, …
Performance analysis of the out-of-band signaling scheme for high speed wireless LANs
2005
In this paper, we study the performance of our earlier proposed out-of-band signaling (OBS) scheme for high speed wireless local area networks (WLANs). We employ the system approximation technique for modeling of the OBS scheme. An equivalent state dependent single server queue, that describes the OBS scheme, is constructed for the analysis of the throughput and delay performances. Moreover, we study the throughput optimization of the OBS scheme, which provides a means for optimizing the performance of the OBS scheme, given a particular network environment. Finally, we conduct several simulation experiments to validate our analytical results.
Secure and efficient data storage in unattended wireless sensor networks
2009
©2009 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. Article also available from publisher: http://dx.doi.org/10.1109/NTMS.2009.5384753 Providing forward and backward secrecy is still a big challenge in Unattended Wireless Sensor Networks (UWSNs), though some storage schemes have been proposed. Additionally, high storage requirement needs efficient storage techniques. In this paper, we propose a novel homomorphic…
No Reservations Required: Achieving Fairness between Wi-Fi and NR-U with Self-Deferral Only
2021
Wireless technologies coexisting in unlicensed bands should receive a fair share of the available channel resources, even when they use different access methods. We consider the problem of coexistence between Wi-Fi and New Radio Unlicensed (NR-U) nodes, which employ, respectively, a random and scheduled access scheme. The latter typically resorts to reservation signals (RSs), which allow keeping the control of the channel until the start of the next synchronized slot. This mechanism, although effective for increasing the channel access opportunities of scheduled-based nodes, is also a waste of channel resources. We investigate alternative solutions, based on self-deferral only. We built ana…
Fading mitigation coding techniques for space to ground free space optical communications
2014
In this manuscript, a Geostationary satellite-toground Free Space Optics (FSO) downlink channel model has been implemented, which is able to predict temporal irradiance fluctuations caused by scintillation at a wide range of turbulence conditions and for different values of the zenith angle. In order to mitigate fading events that occur in FSO communications, we have also tested the performance of three different families of Rateless Codes (Luby Transform, Raptor and RaptorQ) into our model and found that RaptorQ is the best candidate to mitigate errors in FSO links. Keywords— Optical Wireless Communications; Space-toGround FSO links, time-series, rateless codes; fading mitigation
Characterization of single semiconductor nanowires by synchrotron radiation nanoprobe
2012
In this work, we report on the results of the characterization of single semiconductor nanowires by x-ray fluorescence nanoprobe. Wurtzite InGaN and Co-implanted ZnO single nanowires were studied. Ternary semiconductor nanowires show an axial inhomogeneous elemental distribution, with Ga accumulating at the bottom and In at the top of the wires. The ZnO NWs, on the other hand, show a homogeneous distribution of the Co implanted along the nanowires, without signatures of clustering or segregation effects induced by the implantation. No signatures of unintentional doping are observed neither in the InGaN nor the ZnO NWs. These overall results demonstrate the suitability of X-ray fluorescence …