- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Underwater optical wireless sensor networks using resource allocation
摘要： Optical wireless communications is an energy efficient and cost-effective solution for high speed and high secure wireless connections. In this paper, we propose an underwater optical wireless sensor network using multiple input multiple output technique and power allocation algorithm for supporting multiple users with the impacts of underwater channel uncertainty interferences. In proposed power allocation algorithm, all the LED nodes in are coordinated and controlled by a central controller; each LED node supports all the users within its field of view. To separate users, optical code division multiple access is used; cyclic optical orthogonal code working as CDMA code is employed. At the receiver, a minimal mean squared error (MMSE) filter is uniquely designed for each user. The MMSE filters and the assigned power can be jointly optimized to improve the overall throughput and signal to noise ratio. Since the system performance may be impacted by the underwater channel uncertainty, the proposed power allocation can use the predicted channel uncertainty variance to reduce the interference of the channel uncertainty and improve the signal to noise ratio. Compared to the equal power allocation algorithm, the proposed algorithm can support longer transmission distance, higher bit rate and lower bit error rate.
关键词： Multiple access interference,Underwater communications,Wireless sensor networks,Channel uncertainty,MIMO system,CDMA,Optical wireless communications,Resource allocation
更新于2025-09-23 15:23:52
-
[IEEE 2018 IEEE 23rd International Workshop on Computer Aided Modeling and Design of Communication Links and Networks (CAMAD) - Barcelona (2018.9.17-2018.9.19)] 2018 IEEE 23rd International Workshop on Computer Aided Modeling and Design of Communication Links and Networks (CAMAD) - Harvesting artificial light indoors to power perpetually a Wireless Sensor Network node
摘要： Wireless Sensor Networks (WSN) devices are usually battery powered and thereby their lifetime is limited. This issue leads to lose data measurements and thus to a performance loss of the underlying WSN application. It also increases the maintenance cost in Internet of Things (IoT) scenarios with a huge number of WSN devices. Energy harvesting (EH) is one of the key technologies to solve this issue. In this paper, energy harvesting by artificial light is proposed to power WSN devices in indoor scenarios. Contrary to the state-of-the-art related work, this paper experimentally demonstrates that it is possible, under certain conditions, to achieve energy neutral WSN devices by harvesting energy from artificial light. The experimental setup consists of an EH module, which powers a WSN source data acquisition node, and a WSN sink node which receives the data sent by the first. The EH module consists of a photovoltaic (PV) cell, a boost converter and a 3V coin battery.
关键词： photovoltaic cell,Wireless Sensor Networks,Energy harvesting,boost converter,Internet of Things
更新于2025-09-23 15:22:29
-
[IEEE 2019 IEEE Conference on Information and Communication Technology (CICT) - Allahabad, India (2019.12.6-2019.12.8)] 2019 IEEE Conference on Information and Communication Technology - LEDCOM: A Novel and Efficient LED Based Communication for Precision Agriculture
摘要： Wireless Sensor Networks and Satellite Remote Sensing are some of the existing techniques that are used to collect, analyze and interpret data from the agricultural crop sites. However, there are certain limitations common to both of these techniques that are concerned with the latency and the resolution of the data collected. UAVs (Unmanned Aerial Vehicles) are becoming another alternative that has become integral nowadays due to its affordable and scalable nature while offering user friendly requirements and customizations. This proposes a novel and cost-effective technique (LEDCOM) that harnesses the capabilities of ground sensors and unmanned UAV while using computer vision methods to produce a qualitative data analysis system that describes the crop site under supervision. An UAV is assumed to collect the ground based sensor node data in the form of binary patterns on LED Arrays that is encoded in the image taken by a camera of a drone. Image processing techniques are used to identify and decode the LED sequences from the arrays. The performance of the proposed system is evaluated under different features and image resolutions within the same lighting conditions. A promising performance is observed for LED pattern identi?cation from the challenging images taken from a height.
关键词： Computer Vision,LED Pattern Identi?cation,UAVs,Wireless Sensor Networks,Precision Agriculture,Remote Sensing
更新于2025-09-23 15:21:01
-
[IEEE 2018 IEEE 8th International Conference Nanomaterials: Application & Properties (NAP) - Zatoka, Ukraine (2018.9.9-2018.9.14)] 2018 IEEE 8th International Conference Nanomaterials: Application & Properties (NAP) - Optical and Thermal Analysis of PVB Encapsulant Polymer Functionalized with Luminescent Organic Dye as Emerging Material for Photovoltaic Application
摘要： Wireless sensor networks (WSNs) can utilize the unlicensed industrial, scienti?c, and medical (ISM) band to communicate the sensed data. The ISM band has been already saturated due to the overlaid deployment of WSNs. To solve this problem, WSNs have been powered up by cognitive radio (CR) capability. By using CR capability, WSNs can utilize the spectrum holes opportunistically. The sensor nodes, which need large bandwidth to transmit their sensed data from source to destination require some scheme, which should be able to provide them a wide band channel whenever required. Channel bonding (CB) is a technique through which multiple contiguous channels can be combined to form a single wide band channel. By using CB technique, CR-based WSN nodes attempt to ?nd and combine contiguous channels to avail larger bandwidth. In this paper, we show that by increasing the number of channels, the probability of ?nding contiguous channels decreases. Moreover, we then propose a primary-radio (PR) user-activity-aware CB algorithm and compare it with three state-of-the-art schemes: SWA, KNOWS, and AGILE. It has been demonstrated through extensive NS-2 simulations that intelligent CB decisions can reduce harmful interference to PR nodes. We ?nd that CB in CR sensor networks attempts to provide greater bandwidth and utilizes the spectrum effectively.
关键词： cognitive radio,dynamic spectrum access,wireless sensor networks,Channel bonding
更新于2025-09-23 15:21:01
-
[IEEE 2018 International Symposium on Micro-NanoMechatronics and Human Science (MHS) - Nagoya, Japan (2018.12.9-2018.12.12)] 2018 International Symposium on Micro-NanoMechatronics and Human Science (MHS) - Laser Lift-Off Process for Additive Micropatterning of Functional Particles and Films
摘要： While visual or tactile image data have been conventionally processed via filters or perceptron-like learning machines, the recent advances of computational topology may make it possible to successfully extract the global features from the local pixelwise data. In fact, some inventive algorithms have succeeded in computing the topological invariants, such as the number of objects or holes and irrespective of the shapes and positions of the touches. However, they are mostly offline algorithms aiming at big data. A real-time algorithm for computing topology is also needed for interactive applications such as touch sensors. Here, we propose a fast algorithm to compute the Euler characteristics of touch shapes by using the Poincare–Hopf index for each pixel. We demonstrate that our simple algorithm, implemented solely as logical operations in Arduino, correctly returns and updates the topological invariants of touches in real time.
关键词： invariance,sensor networks,touch counter,Poincare-Hopf index,topology
更新于2025-09-23 15:21:01
-
[IEEE 2018 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC) - Sydney, Australia (2018.11.10-2018.11.17)] 2018 IEEE Nuclear Science Symposium and Medical Imaging Conference Proceedings (NSS/MIC) - A Laser-based Time Calibration System for the MEG II Timing Counter
摘要： Wireless sensor networks (WSNs) can utilize the unlicensed industrial, scientific, and medical (ISM) band to communicate the sensed data. The ISM band has been already saturated due to the overlaid deployment of WSNs. To solve this problem, WSNs have been powered up by cognitive radio (CR) capability. By using CR capability, WSNs can utilize the spectrum holes opportunistically. The sensor nodes, which need large bandwidth to transmit their sensed data from source to destination require some scheme, which should be able to provide them a wide band channel whenever required. Channel bonding (CB) is a technique through which multiple contiguous channels can be combined to form a single wide band channel. By using CB technique, CR-based WSN nodes attempt to find and combine contiguous channels to avail larger bandwidth. In this paper, we show that by increasing the number of channels, the probability of finding contiguous channels decreases. Moreover, we then propose a primary-radio (PR) user-activity-aware CB algorithm and compare it with three state-of-the-art schemes: SWA, KNOWS, and AGILE. It has been demonstrated through extensive NS-2 simulations that intelligent CB decisions can reduce harmful interference to PR nodes. We find that CB in CR sensor networks attempts to provide greater bandwidth and utilizes the spectrum effectively.
关键词： cognitive radio,dynamic spectrum access,Channel bonding,wireless sensor networks
更新于2025-09-23 15:19:57
-
[IEEE 2019 Photonics & Electromagnetics Research Symposium - Fall (PIERS - Fall) - Xiamen, China (2019.12.17-2019.12.20)] 2019 Photonics & Electromagnetics Research Symposium - Fall (PIERS - Fall) - Adjustable Dual-frequency FSS-amplifier Metasurface
摘要： Asynchronous network coding has the potential to improve wireless network performance compared with simple routing. However, to achieve the maximum network coding gain, the encoding node consumes a few computing and storage resources that may be unaffordable for wireless sensor networks such as CubeSats. An analogous threshold strategy, called best effort network coding (BENC), which requires only minimal storage resources and no computing resources, is investigated in this paper as an efficient and convenient method of network coding. In this strategy, a new packet arrival evicts the head packet when the queue is full to avoid excessively long waits. Moreover, in contrast to other methods that require a queue for each flow, the BENC uses only one queue for the two coded flows. In addition, the problem of time interval distribution for the output flow, which combines two independent flows, is investigated, and the network coding gain is then analyzed. While the maximum coding gain requires infinite buffer capacity under two independent Poisson arrivals with the same transmission rates, the calculation results show that the BENC needs only 4 buffers to achieve 90% of the maximum coding gain and can reach 99% of the maximum coding gain using 50 buffers. These results are verified by numerical simulations.
关键词： wireless sensor networks,queue capacity,best effort,queueing analysis,Network coding
更新于2025-09-23 15:19:57
-
Resonant Beam Communications with Photovoltaic Receiver for Optical Data and Power Transfer
摘要： Asynchronous network coding has the potential to improve wireless network performance compared with simple routing. However, to achieve the maximum network coding gain, the encoding node consumes a few computing and storage resources that may be unaffordable for wireless sensor networks such as CubeSats. An analogous threshold strategy, called best effort network coding (BENC), which requires only minimal storage resources and no computing resources, is investigated in this paper as an efficient and convenient method of network coding. In this strategy, a new packet arrival evicts the head packet when the queue is full to avoid excessively long waits. Moreover, in contrast to other methods that require a queue for each flow, the BENC uses only one queue for the two coded flows. In addition, the problem of time interval distribution for the output flow, which combines two independent flows, is investigated, and the network coding gain is then analyzed. While the maximum coding gain requires infinite buffer capacity under two independent Poisson arrivals with the same transmission rates, the calculation results show that the BENC needs only 4 buffers to achieve 90% of the maximum coding gain and can reach 99% of the maximum coding gain using 50 buffers. These results are verified by numerical simulations.
关键词： queueing analysis,queue capacity,Network coding,wireless sensor networks,best effort
更新于2025-09-23 15:19:57
-
[IEEE 2019 26th International Workshop on Active-Matrix Flatpanel Displays and Devices (AM-FPD) - Kyoto, Japan (2019.7.2-2019.7.5)] 2019 26th International Workshop on Active-Matrix Flatpanel Displays and Devices (AM-FPD) - How to use Synchrotron Soft X-Ray for Analysis of Perovskite Solar Cell
摘要： Wireless sensor networks (WSNs) can utilize the unlicensed industrial, scientific, and medical (ISM) band to communicate the sensed data. The ISM band has been already saturated due to the overlaid deployment of WSNs. To solve this problem, WSNs have been powered up by cognitive radio (CR) capability. By using CR capability, WSNs can utilize the spectrum holes opportunistically. The sensor nodes, which need large bandwidth to transmit their sensed data from source to destination require some scheme, which should be able to provide them a wide band channel whenever required. Channel bonding (CB) is a technique through which multiple contiguous channels can be combined to form a single wide band channel. By using CB technique, CR-based WSN nodes attempt to find and combine contiguous channels to avail larger bandwidth. In this paper, we show that by increasing the number of channels, the probability of finding contiguous channels decreases. Moreover, we then propose a primary-radio (PR) user-activity-aware CB algorithm and compare it with three state-of-the-art schemes: SWA, KNOWS, and AGILE. It has been demonstrated through extensive NS-2 simulations that intelligent CB decisions can reduce harmful interference to PR nodes. We find that CB in CR sensor networks attempts to provide greater bandwidth and utilizes the spectrum effectively.
关键词： cognitive radio,dynamic spectrum access,Channel bonding,wireless sensor networks
更新于2025-09-23 15:19:57
-
Optical Communications and Networks
摘要： Due to energy and throughput constraints of visual sensing nodes, in-node energy conservation is one of the prime concerns in visual sensor networks (VSNs) with wireless transceiving capability. To cope with these constraints, the energy ef?ciency of a VSN for a given level of reliability can be enhanced by recon?guring its nodes dynamically to achieve optimal con?gurations. In this paper, a uni?ed framework for node classi?cation and dynamic self-recon?guration in VSNs is proposed. The proposed framework incorporates quality-of-information (QoI) awareness using peak signal-to-noise ratio-based representative metric to support a diverse range of applications. First, for a given application, the proposed framework provides a feasible solution for the classi?cation of visual sensing nodes based on their ?eld-of-view by exploiting the heterogeneity of the targeted QoI within the sensing region. Second, with the dynamic realization of QoI, a strategy is devised for selecting suitable con?gurations of visual sensing nodes to reduce redundant visual content prior to transmission without sacri?cing the expected information retrieval reliability. The robustness of the proposed framework is evaluated under various scenarios by considering: 1) target QoI thresholds; 2) degree of heterogeneity; and 3) compression schemes. From the simulation results, it is observed that for the second degree of heterogeneity in targeted QoI, the uni?ed framework outperforms its existing counterparts and results in up to 72% energy savings with as low as 94% reliability.
关键词： visual sensor networks,dynamic reconfiguration,node,3D field-of-view modelling,classification,energy optimization,quality-of-information,reliability analysis
更新于2025-09-23 15:19:57