Passive Nodes Research Articles

Real-time wavelength routing based on Bragg reflection with integrated forward Raman for long-reach networks

We experimentally demonstrate the all-optical efficient technique for dynamic full-duplex wavelength routing and reach extension through adoption of passive fibre Bragg grating (FBG), energy efficient vertical cavity surface emitting lasers (VCSELs) and high gain forward Raman pump. In this study, two VCSEL channels at 1 549.62 nm and 1 550.01 nm are directly modulated with a 8.5 Gbit/s data signal each, and transmitted over 25.5 km fibre to a passive single mode FBG-based wavelength routing node. The precise wavelength selectivity of the FBG is exploited to achieve all-optical real-time wavelength routing of the 1 549.62 nm VCSEL channel with a maximum insertion loss of 22.1 dB. The 1 550.01 nm channel is transmitted through the FBG with a maximum penalty of 1.03 dB. By utilizing the 7.2 dB flat gain of a forward Raman pump, the routed 1 549.62 nm VCSEL channel is transmitted over 76.7 km fibre with a maximum penalty of 3.84 dB at bit error rate (BER) of 5−5. Our technique is all-optical, power efficient as it employs passive FBG and circulators and has low cross talk allied to precise wavelength selectivity of the technique.

High-reliability optical process level network in smart substation

A novel scheme for high-reliability optical process level network (OPLN) with all-optical passive edge nodes in smart substation is first proposed, supporting both sampled value and generic object oriented substation event services with multicast traffic pattern. The edge node consists of n passive optical distribution modules and one arrayed waveguide grating, realizing the all-optical interconnection inside bays to reduce the optical-electrical and electrical-optical processes. A software defined network based center switch schedules all intelligent electrical devices in the network using multi-point control protocol. The analytical model for the OPLN reliability is established based on fault tree analysis. The results show that the OPLN can achieve almost two-fold mean-time-between-failure as compared to the Ethernet switch based network. Moreover, 99.99% availability can be obtained when network scale is up to 24 bays under dual-network redundancy.

Tcp Performance and Throughput Fairness Optimization in a Multi-Hop Pipeline Network

Node starvation wireless sensor network (WSN) is a critical factor that affects the overall performance in a typical multi-hop linear network especially in an extensive scale network. The unfairness of sharing network resources with all source nodes in a multi-hop linear network amplifies the node starvation that often results in passive nodes in a network. This factor becomes critical with the increasing network density, aggressive data transfer, single destination node and inadequate data scheduling. This paper highlights the Delayed acknowledgement timeout for flat one-tier throughput critical application model (DAT-FTCAM) a mathematical fairness model that ensure maximum throughput fairness for pipeline network scenario. The DAT-FTCAM enables the users to calculate the maximum delayed acknowledgement timeout for transmission control protocol (TCP) proportional to the travel time or difference between a source and a destination node. The implementation of DAT-FTCAM technique with modified TCP parameters on NS2 has revealed a network fairness index of above 0.99 with optimum network performance in a scalable pipeline network. The DAT-FTCAM decreases data packet collision and eliminates passive nodes in a pipeline network with optimum throughput fairness.

CMOS RF Transmitters with On-Chip Antenna for Passive RFID and IoT Nodes

The performances of two RF transmitters, monolithically integrated with their antennas on a single CMOS microchip fabricated in a standard 0.35 µm process, are presented. The usage of these architectures in the Internet of Things (IoT) paradigm is envisioned, as part of a custom conceived data transmission system. The implemented circuits use two different directly on–off keying (OOK) modulated oscillator topologies whose outputs are employed to feed two loop antennas. The powering of both transmitters is duty-cycled for reducing the average power consumption to a few tenths of a microwatt, allowing the usage as low-power transmitters for IoT nodes. The integrated loop antennas radiate sufficient power for a few meters’ communication range. The OOK transmitted signal can be easily detected using a commercial receiver.

Rescue: Wireless power-enabled communication architecture for earthquake rescue operations

In a natural disaster such as an earthquake, it is vital to know the number of people trapped under the ruins. To address this problem, we propose RESCUE — wiREless backScattering CommUnication-based disastEr recovery system. RESCUE is composed of special Radio-frequency identification (RFID) readers and sensors that are used to determine the total number of people under the ruins. Passive wireless sensor nodes are placed inside the building during construction and are equipped with a camera that is activated during an earthquake. After the earthquake, communication to the passive tags of sensors is achieved by wireless power transfer from a reader located outside the ruins. Tags harvest this energy and send the image data stored by the camera. We also design an antenna structure to maximize simultaneous wireless information and power transfer (SWIPT) for devices under ruins. We analyze the communication channel between reader and sensors and derive a channel model over ruins. Furthermore, we obtain the results of experimental study where we validate the derived channel model. Results show that RESCUE can collect the desired data in a relatively short time, and hence, is a promising disaster recovery system architecture.

Distributed coestimation in heterogeneous sensor networks

We propose a system-theoretical dynamic information fusion framework for heterogeneous sensor networks, where a sensor network with nonidentical node information roles and nonidentical node modalities is considered. Nonidentical node information roles allow nodes to be either active or passive in the sense that active nodes receive observations from a process, whereas passive nodes do not receive any information. Active and passive roles of nodes can be fixed or varying in time. Nonidentical node modalities allow active nodes to receive different classes of measurements from the process. For this class of sensor networks, we propose a distributed input and state coestimation architecture, where the time evolution of input and state updates of each node both depend on the local input and state information exchanges. Using Lyapunov theory and linear matrix inequalities, we establish stability and performance guarantees of the sensor network executing the proposed distributed coestimation architecture under local sufficient conditions.

Numerical Optimization of a Fully Cross-Coupled Rectifier Circuit for Wireless Passive Ultra Low Power Sensor Nodes.

In the context of the Internet of Things, billions of devices—especially sensors—will be linked together in the next few years. A core component of wireless passive sensor nodes is the rectifier, which has to provide the circuit with sufficient operating voltage. In these devices, the rectifier has to be as energy efficient as possible in order to guarantee an optimal operation. Therefore, a numerical optimization scheme is proposed in this paper, which is able to find a unique optimal solution for an integrated Complementary Metal-Oxide-Semiconductor (CMOS) rectifier circuit with Self-Vth-Cancellation (SVC). An exploration of the parameter space is carried out in order to generate a meaningful target function for enhancing the rectified power for a fixed communication distance. In this paper, a mean conversion efficiency is introduced, which is a more valid target function for optimization than the Voltage Conversion Efficiency (VCE) and the commonly used Power Conversion Efficiency (PCE) and is defined as the arithmetic mean between PCE and VCE. Various trade-offs between output voltage, PCE, VCE and MCE are shown, which provide valuable information for low power rectifier designs. With the proposed method, a rectifier in a low power 55 nm process from Globalfoundries (GF55LPe) is optimized and simulated at −30 dBm input power. A mean PCE of 63.33% and a mean VCE of 63.40% is achieved.

Secure and Efficient Location-Aided Routing Against DDOS Attack in Manet

A wireless LAN is one in which a mobile user can connect to a local area network (LAN) through a wireless (radio) connection. There are many routing protocols used in wireless networks for transmission of message, among which, Location-Aided Routing (LAR) protocol is used to find the location of destination. This may be possible using Global Positioning System (GPS) in mobile. We concentrate on other malicious attacks that would have caused tremendous loss by impairing the functionalities of the computer networks. Denial of Service (DoS) and Distributed DoS (DDoS) attacks are two of the most harmful threats to the MANET functionality. From this point of view, LAR provides a solution against DoS and DDoS attacks. LAR does not have any security mechanism, so we propose a SE_LAR technique which includes traffic analysis methods and extended OEDA method. It is helpful to analyze the traffic, to detect an overwhelming traffic, legitimate nodes, congestion on network, and snooping attacks. Mobile Ad Hoc Network (MANET) is even more vulnerable to such attacks. So, in this paper, we propose Secure Location-Aided Routing (SE_LAR). Its results are compared with existing secure routing protocols like ISE_DREAM, SE_DREAM protocols. Using the existing SE_DREAM routing protocol malicious nodes are detected by traffic analysis process which is to monitor flooding impact on MANET. The OEDA method discriminates the attacker nodes from reputable nodes by evaluating the addresses in the response signal. But, it cannot be used for dense network, and cannot detect indirect Sybil attack. So, we introduce extended OEDA method with two schemes such as by refering cache memory of neighbor node scheme, and passive Sybil node identity detection, which is incorporated with SE_LAR routing protocol. OEDA method is currently incorporated with the SE_DREAM protocol, generally better known as ISE_DREAM, to produce the route to destination substantially more robust against DDOS attack. Finally we decide using the performance parameters to find out the best alternative among the three different routing protocols. Calculation of the performance of the computation compares SE_DREAM, ISE-DREAM and SE-LAR standards, the overall performance measurements by the NS2 simulator and using the parameters. To determine the effect of network size on the total performance of these protocols, we have three different phenomena.

Resource configuration for minimizing source energy consumption in multi-carrier networks with energy harvesting relay and data-rate guarantee

Simultaneous wireless information and power transfer (SWIPT) is a promising technique for wireless energy harvesting, which enables a relay node to overcome its unwillingness due to the energy awareness, with essentially protecting it from excessively depleting energy reserves. To further improve the energy efficiency, the energy consumption minimization problem aims at minimizing the energy consumption of an active source node, which drives the passive relay node with energy harvesting capability to forward data to the destination. This is studied by jointly considering transmission power limits, time switching factors, and data-rate demand, etc., in a decode-and-forward relay network with SWIPT. The energy consumption minimization problem is formulated as a non-convex optimization problem. The facilitation of the derivation of the optimal solution is through transforming it into an equivalent convex optimization problem by variable substitution. Since the problem is not always feasible, a feasibility assessment problem is then developed by introducing an assessing factor. Simultaneously solving the above inter-related problems, i.e., energy consumption minimization and feasibility assessment, they are unified in a convex-optimization framework, in which both the result about the feasibility assessment and the optimal solution (if it exists) can be obtained. Even if the problem is not feasible, the achievable maximum data rate that network resources can support can be obtained as well. Simulation results further validate that energy consumption minimization-feasibility assessment algorithm is effective in minimizing source energy consumption and in realizing optimal resource configuration.

Integrated cmos rectifier for rf-powered wireless sensor network nodes

This article presents a review of the CMOS rectifier for radio frequency energy harvesting application. The on-chip rectifier converts the ambient low-power radio frequency signal coming to antenna to useable DC voltage that recharges energy to wireless sensor network (WSN) nodes and radiofrequency identification (RFID) tags, therefore the rectifier is the most important part of the radio frequency energy harvesting system. The impedance matching network maximizes power transfer from antenna to rectifier. The design and comparison between the simulation results of one- and multi-stage differential drive cross connected rectifier (DDCCR) at the operating frequencies of 2.44GHz, and 28GHz show the output voltage of the multi-stage rectifier doubles at each added stage and power conversion efficiency (PCE) of rectifier at 2.44GHz was higher than 28GHz. The (DDCCR) rectifier is the most efficient rectifier topology to date and is used widely for passive WSN nodes and RFID tags.

Assessing a simplified procedure to reconcile distributed renewable and interactive energy systems and urban patterns. The case study of school buildings in Rome

ABSTRACTDistributed, Renewable and Interactive energy Systems (DRIs) are revolutionizing the concept of infrastructure by introducing a set of new properties. The implications of the new system properties in the realm of Urban Design are often neglected. This paper proposes a procedure to reconcile DRIs and urban patterns. This procedure is tested on 23 school buildings in four urban regions of the Ostiense district in Rome. Findings suggest that the identification of existing buildings as active, neutral and passive nodes in DRIs can make a contribution to Urban Design decisions to exploit the renewable energy production capacity inherent in urban patterns.

Redundant Computing Resources Management of Integrated Modular Avionics

In article the structure and the control algorithm are considered by diverse redundancy of the computing system of the perspective integrated modular avionics. Computing resources of the integrated modular avionics system are generally represented by heterogeneous computing systems used for information processing as part of the onboard integrated computing environment. The basis of heterogeneous computing systems are processor nodes, redundancy of computing systems is that the number of processor nodes is greater than one. The task is to synthesize such a computer system in which the automatic control of redundant computational resources would be carried out by using the own capabilities of the processor nodes and without the use of additional hardware resources. It is considered that the redundant computer system performs meaningful calculations of the problem solved by several processor nodes in parallel. All meaningful calculations for any signs initially divided into relatively short stages, providing an opportunity to assess the effectiveness of the completion of each of them. The computational system redundancy management is based on the periodic calculation and comparison of the success indicators of the stage. Pairwise arbitration of processor nodes is carried out according to a hierarchical scheme by comparing the values of the success indicators of the stages of the same name. Subsequent reconfiguration of the computer system allocates passive and leading processor nodes in pairs at all levels of the hierarchical scheme. The failure of the passive processor node does not affect the execution of the main cycle. The failure of the host processor node does not cause interruptions in the output of the results of calculations, but destroys the structure of reserves, which is restored after arbitration in the next cycle. Failure of the lead CPU top node leads to the failure output in the current cycle, the computational process is restored along with the new hierarchy of the computing system in the next cycle. The proposed solution is aimed at parrying both hardware failures and software malfunction. The methodical example based on the computer system of the modern onboard equipment complex of the transports category aircraft is resulted.

Distributed computing using SMART sensors in industrial automation framework

Transition from single node computing to complex distributed computing environments has proven its efficiency in the computer networks especially in executing heavy computational tasks. The sensors on the floor have become smart with additional computational capabilities compared to passive acquisition nodes. We merged these two entities and evaluated the distributed computing of PLC load on smart sensors on an industrial automation framework. We have utilized SoC (Raspberry Pi) to build a SMART sensor which has allowed us to create a distributed and scalable sensor network structure. This structure in conjunction with state of the Art Industrial Automation network improves the performance of the Automation networks.

Distributed Generation Harmonic Interaction in the Active Distribution Network

Significant increase of distributed generation (DG) presence and active distribution network (ADN) development cause changes in distribution network’s power quality (PQ), mostly in distorted system voltages and currents. This paper analyses harmonics generation from multiple DG types, such as solar and biogas power plants, and simulates harmonic interactions in ADN in order to identify potential PQ issues. Each harmonic source observed in this paper was modelled according to IEC 61 000 with the model parameters provided by power quality measurements in the real system on several DG power plants and passive consumer nodes. A harmonic load flow is performed on a detailed ADN model for different presumed DG expansion scenarios that indicate the complexity of the DG impact on the AND’s PQ. Quantitative and qualitative graphical presentation for cumulative and the most significant ADN nodes is given and the assessment for the potential ADN development based on PQ indices is proposed.

High-Content Optical Codes for Protecting Rapid Diagnostic Tests from Counterfeiting.

Warnings and reports on counterfeit diagnostic devices are released several times a year by regulators and public health agencies. Unfortunately, mishandling, altering, and counterfeiting point-of-care diagnostics (POCDs) and rapid diagnostic tests (RDTs) is lucrative, relatively simple and can lead to devastating consequences. Here, we demonstrate how to implement optical security codes in silicon- and nitrocellulose-based flow paths for device authentication using a smartphone. The codes are created by inkjet spotting inks directly on nitrocellulose or on micropillars. Codes containing up to 32 elements per mm2 and 8 colors can encode as many as 1045 combinations. Codes on silicon micropillars can be erased by setting a continuous flow path across the entire array of code elements or for nitrocellulose by simply wicking a liquid across the code. Static or labile code elements can further be formed on nitrocellulose to create a hidden code using poly(ethylene glycol) (PEG) or glycerol additives to the inks. More advanced codes having a specific deletion sequence can also be created in silicon microfluidic devices using an array of passive routing nodes, which activate in a particular, programmable sequence. Such codes are simple to fabricate, easy to view, and efficient in coding information; they can be ideally used in combination with information on a package to protect diagnostic devices from counterfeiting.

A Stackelberg game for street-centric QoS-OLSR protocol in urban Vehicular Ad Hoc Networks

In this paper, we address the problem of routing in urban Vehicular Ad Hoc Networks (VANETs) using proactive Optimized Link State Routing (OLSR) protocol in the presence of passive malicious nodes. OLSR protocol routes through MultiPoint Relays (MPRs) that are selected according to neighbors' reachability and uniqueness. However, in urban VANETs, other parameters such as node's mobility and street topology are also of significance. These parameters can also be taken into consideration to improve the quality of selected MPRs. However, an MPR can adopt a passive malicious behavior by not cooperating with other nodes unless rewarded. As a solution, we propose a multi-leader multi-follower Stackelberg game model that motivates nodes to act cooperatively, being MPRs, by increasing their reputation. Collected reputation increments are used to determine the set of nodes (followers) that an MPR (leader) will route for based on nodes' reputation. Simulations conducted using NS3 demonstrate that the proposed Stackelberg game model improves the network performance in terms of stability of MPRs, throughput, and average hop count compared to OLSR and the street-centric QoS-OLSR protocol in urban VANET. Additionally, the proposed protocol presents a similar percentage of selected MPRs and end-to-end delay compared to the benchmarks.

Asynchronous Localization With Mobility Prediction for Underwater Acoustic Sensor Networks

Most applications of underwater acoustic sensor networks (UASNs) rely upon reliable location information of sensor nodes. However, the harsh underwater environment makes localization more challenging as compared to terrestrial sensor networks. This paper is concerned with a localization issue for UASNs, subject to clock asynchronization and node mobility. A hybrid architecture including autonomous underwater vehicles (AUVs), active and passive sensor nodes is designed, where AUVs act as anchor nodes to provide localization information for sensor nodes. In order to eliminate the effect of asynchronous clocks and compensate the mobility of sensor nodes, an asynchronous localization algorithm with mobility prediction is provided for active and passive sensor nodes. Then, two localization optimization problems are formulated as minimizing the sum of all measurement errors. To solve the localization optimization problems, iterative least squares estimators are designed. In addition, the convergence analysis and Crame r–Rao lower bound for the localization errors are also provided. Finally, simulation results show that the proposed localization approach can reduce the localization time by comparing with the exhaustive search-based localization method. Meanwhile, the asynchronous algorithm in this paper can effectively eliminate the impact of the clock asynchronization and node mobility.

Square partition‐based node scheduling algorithm for wireless passive sensor networks

SummaryWireless passive sensor networks play an important role in solving the energy limitation of nodes in the Internet of Things, and node scheduling is a significant method used to improve the energy utilization of nodes. In this work, an unused energy model based on analyzing the energy consumption characteristics of passive nodes is proposed because no unified model of passive sensor nodes is reported in previous studies. A rapid square partition clustering method is proposed according to the analysis of the relation between the sensing and communication radii of nodes, and the secondary grouping and node scheduling in each cluster are implemented to ensure the coverage rate of networks. Experimental results show that the state distribution of nodes in the proposed algorithm is favorable. The performance of the proposed algorithm is significantly affected by the P ratio between the working and charging powers of nodes. When the value of P is less than 100, the network coverage and connectivity rate are maintained at more than 95% and 90%, respectively, and are both higher than the existing algorithm.

WET-Enabled Passive Communication Networks: Robust Energy Minimization With Uncertain CSI Distribution

In this paper, we study wireless energy transfer-enabled passive communication networks, where passive nodes (PNs) harvest radio frequency (RF) energy emitted by an active node (AN) and/or scatter the RF wave to a receiver for data transfer. The performance of such networks highly depends on channel state information (CSI), but its acquisition is quite challenging since energy-and-hardware constrained PNs are generally unable to estimate or feedback CSI. We propose a harvest-while-scatter protocol, where every PN uses the time when other PNs scatter to harvest RF energy, while only introducing minimum interference. Furthermore, we develop a channel training approach for this protocol to estimate means and (co)variances of channel gains via collecting and utilizing historical data and energy transmissions. To minimize the energy consumed at the AN with limited statistical CSI, we formulate a distributionally robust energy minimization problem involving a non-convex objective function and a quality-of-service chance constraint. In addition, we develop an iterative algorithm to optimally solve it with low complexity. Simulation results show the effectiveness of our proposed protocol and algorithm, and reveal the effect of relative node locations on energy consumption in terms of energy harvesting and data transfer.

Shape Control of Compliant, Articulated Meshes: Towards Modular Active-Cell Robots (MACROs)

In this letter, we explore the shape control of compliant, articulated meshes created from shape memory alloy (SMA)-based linear actuators (Active Cells). These compliant meshes form the mechanical subsystem of a class of proposed modular active-cell robots (MACROs). Our “Active Cells” are centimeter-scale SMA actuators capable of ~25% linear strain. The deformation of MACRO meshes in response to current inputs at the passive nodes are modeled and validated for accuracy in prior work. In this letter, we investigate an efficient and scalable control policy that allows us a given MACRO to be electrically-driven to achieve a specified shape. Validation experiments on a range of MACRO simulations establish a high degree of accuracy and repeatability of the controller. The control strategy is shown to be efficient and robust to variations in start- and target-shapes, and in mesh complexity.