Low-rate Wireless Personal Area Research Articles

Developments on an IEEE 802.15.4-based wireless sensor network

In this paper a summary is given of the ongoing research at the Belgian Royal Military Academy in the field of mobile ad hoc networks in general and wireless sensor networks (WSNs) in particular. In this study, all wireless sensor networks are based on the physical and the medium access layer of the IEEE 802.15.4 low rate wireless personal area networks standard. The paper gives a short overview of the IEEE 802.15.4 standard in the beaconless mode together with a description of the sensor nodes and the software used throughout this work. The paper also reports on the development of a packet sniffer for IEEE 802.15.4 integrated in wireshark. This packet sniffer turns out to be indispensable for debugging purposes. In view of future applications on the wireless network, we made a theoretical study of the effective data capacity and compared this with measurements performed on a real sensor network. The differences between measurements and theory are explained. In case of geograph- ically meaningful sensor data, it is important to have a knowledge of the relative position of each node. In the last part of the paper we present some experimental results of positioning based on the received signal strength indicators (RSSI). As one could expect, the accuracy of such a method is poor, even in a well controlled environment. But the method has some potential.

Identifying Misbehaving Greedy Nodes in IoT Networks.

One of the central communication infrastructures of the Internet of Things (IoT) is the IEEE 802.15.4 standard, which defines Low Rate Wireless Personal Area Networks (LR- WPAN). In order to share the medium fairly in a non-beacon-enabled mode, the standard uses Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA). The nature of connected objects with respect to various resource constraints makes them vulnerable to cyber attacks. One of the most aggressive DoS attacks is the greedy behaviour attack which aims to deprive legitimate nodes to access to the communication medium. The greedy or selfish node may violate the proper use of the CSMA/CA protocol, by tampering its parameters, in order to take as much bandwidth as possible on the network, and then monopolize access to the medium by depriving legitimate nodes of communication. Based on the analysis of the difference between parameters of greedy and legitimate nodes, we propose a method based on the threshold mechanism to identify greedy nodes. The simulation results show that the proposed mechanism provides a detection efficiency of 99.5%.

GSA-RPI: GSA based Rendezvous Point Identification in a two-level cluster based LR-WPAN for uncovering the optimal trajectory of Mobile Data Collection Agent

Energy efficient data collection with minimum delay is very essential for IoT applications using sensors attached to Low Rate Wireless Personal Area Networks (LR-WPAN). The nature and position of the data collection and processing point, termed as Sink, plays a vital role in the data reliability, delay, and network lifetime. The static sink causes hot-spot problem to occur in Wireless Sensor Network (WSN), since the nodes nearer to the sink may die quickly. The Mobile Data Collection Agent (MDCA), commonly known as Mobile Sink (MS), can be used to mitigate this problem. A two level clustering scheme with an optimal data collection strategy is proposed in this work. In the first level, hierarchical clusters are formed and the Cluster Heads (CHs) are selected based on the residual energy and connectivity of the devices. The CHs are partitioned into disjoint sets and each set is represented by a Rendezvous Point (RP) that covers every element in the set. In the second level clustering, a deterministic approach is used for the RP identification followed by a meta-heuristic approach known as Gravitational Search Algorithm (GSA) for RP optimization. Finally, the MDCA collects data by visiting RPs along the path obtained using Simulated Annealing (SA). The proposed method is compared with Particle Swarm Optimization based path finding, SPT-GDA, and BR-CTR algorithms. The algorithms are analyzed for number of CHs, RPs, path length, Average Residual Energy, and Network Lifetime in LR-WPAN.

Developing new connectivity architectures for local sensing and control IoT systems

While improvement can be done in every component of the Internet of Things (IoT) as an evolving technology, this work focuses on connectivity. Currently, the main in-building connectivity technology for IoT enterprise deployments is the low rate wireless personal area network (LR-WPAN). However, despite the low power and complexity, the two main issues of the LR-WPAN are very slow data access and short coverage range. To address these issues, 802.11ax can be a promising alternative due to its new IoT-oriented features that explicitly target the resource-constraint requirements. This work proposes and implements two IoT connectivity architectures to deploy the 11ax protocol stack in the sensor motes for sensing the environment and also in the backhaul link to collect and relay the sensed data to the remote processing server. The LR-WPAN is also implemented to be utilized as the baseline and reference point for comparison purposes. Furthermore, a decision model with two integrated modules is proposed to measure and evaluate the performance of the proposed architectures on the basis of the IoT requirement factors that directly contribute to IoT efficiency. The model includes an extensive set of IoT use cases to demonstrate the capabilities of the proposed architectures and determine their contribution to performance enhancement of the IoT systems.

☆Improving IEEE 802.15.4 channel access performance for IoT and WSN devices

IEEE 802.15.4 is a well-known protocol for low power, low rate wireless personal area networks that determines the specifications for the physical layer and the media access control sub-layer. However, IEEE 802.15.4 suffers from several limitations that play a role in reducing its performance such as using a default maximum backoff (macMaxCsmaBackoffs) value for channel access. In terms of energy efficiency, complexity, delay, using a default macMaxCsmaBackoffs does not provide optimum performance in every channel condition. For this reason, we built an adaptive channel access model, ACAMRO that maximizes channel utilization via adjusting macMaxCsmaBackoffs according to channel conditions. ACAMRO provides higher throughput which yields up to a 120% performance gain compared to the default IEEE 802.15.4 setup. It provides an implementation requiring low memory space that is less than 20 kBytes. Measured results show that ACAMRO achieves significant throughput increase, and a low complexity solution for Internet of Things devices.

Improving IEEE 802.15.4 performance with a switched Gold sequence chip formation

Low power, low data rate, low complexity wireless networks are among the most preferred ones in the data communication between wireless sensors, IoT devices, and control applications. IEEE 802.15.4 is a well-known standard for low rate wireless personal area networks which specifies only physical layer and media access control layer. However, IEEE 802.15.4 suffers from several limitations that play a role in deteriorating its performance such as using a standard PN sequence for every channel types. Noise level and interference are significant factors that should be taken into consideration for the achievement of successful communication in different channel characteristics. Utilization of a standard PN sequence would not give optimum performance results for every channel types. In this study, we design a IEEE 802.15.4 peer to peer network simulator to compare the performance of standard IEEE 802.15.4 PN chip sequences and generated Gold sequences in terms of data throughput. The results from Monte Carlo simulations show that Gold sequences give better throughputs compared to standard PN sequence of IEEE 802.15.4. However, both chip sequences could not achieve any data transfer for the noisier channels that show a chip error rate greater than 0.18. To overcome this problem, each symbol of the physical layer protocol data unit is matched with a Gold set with greater spreading factors. Obtained results show that, using variable length Gold sets according to operation environment increases the data throughput in IEEE 802.15.4 networks.

Performance enhancement of LR WPAN spread spectrum system using chaotic spreading sequences

Performance enhancement using chaotic spreading sequences on Low Rate Wireless Personal Area Network is presented. Several one-dimensional chaotic maps are used for generating optimized chaotic sequences for spread spectrum applications. The system parameter of one-dimensional chaotic maps is varied to generate sample-based chaotic signals. Correlation properties analysis is used to generate optimized chaotic sequences. Spreading sequences with a high value of Golay figure of merit are chosen as optimized spreading sequences. Chaotic sequences with high Golay figure of merit factor are expected to have better synchronization and bit error performance. The LR-WPAN model is programmed for USRP (Universal Software Radio Peripheral) software defined radio platform using LabVIEW. The performance of chaotic spreading sequences is evaluated against Gold spreading sequences using the proposed system model. The performance evaluation is based on comparing bit error rate and error vector magnitude in multiple access scenario. The results show that optimized chaotic sequences have better performance than Gold codes.

An Efficient Resource Allocation Scheme for Applications in LR-WPANs Based on a Stable Matching With Externalities Approach

This paper deals with an efficient resource allocation algorithm for Wide-Area Low Rate Wireless Personal Area Networks (LR-WPANs), based on the IEEE 802.15.4 m standard. The proposed scheme aims at lowering the spectrum congestion problems and optimizing performance in terms of data packets dropping probability for all the active clusters of end-devices. The algorithm realizes a many-to-one mapping between the sets of LR-WPANs and available access bands (i.e., TV white space bands). It is based on a matching game with externalities and involves two-side preferences, i.e., clusters over bands and bands over clusters, respectively. The procedure provides high resource reuse, adaptation to changes of system conditions, and improvements on quality of service. Furthermore, a post-matching procedure is also discussed to ensure stability of the provided many-to-one matching. Finally, the good behavior of the matching approach is validated by providing performance comparisons with alternative schemes based on the random assignment, the Brelaz graph coloring algorithm applied in a modified form, and potential game strategy.

Design of wide band printed monopole antenna for low rate wireless personal area networks

AbstractA dual‐band printed monopole antenna useful in low‐rate wireless personal area networks (LR‐PAN) and GPS operation for tablet devices is presented. Antenna has monopole strips arranged in planar configuration on substrate suitable to match standard tablet computer display size. The overall antenna dimension is 150 × 50 × 1.6 mm3. The long and short strips of monopole are separated by notch to increase the bandwidth of antenna. The operating impedance bandwidths of 14.97% and 5.09% are obtained across LR‐PAN band and GPS band, respectively. The presented monopole antenna provides significant gain in order of 4.48 dBi for lower resonant mode and 3.26 dBi for higher resonant mode. The antenna covers LR‐WPAN frequency bands of 868.3 MHz, 915/920 MHz, GSM 850, UMTS/LTE 850, 1.57 GHz GPS bands.

Performance Evaluation of Different Backoff Algorithms in IEEE 802.15.4 using Double Sensing

<p>The IEEE 802.15.4 is the standard for Low Rate Wireless Personal Area network (LR-WPAN). It is widely used in many application areas. The standard uses Slotted CSMA/CA mechanism in its contention access period (CAP) for the beacon enabled mode. The protocol has two modes - single sensing (SS) and double sensing (DS). The protocol also adopts a binary exponential backoff (BEB) algorithm. In this paper, we explore the saturation throughput, delay and energy consumption of this standard with double sensing (DS) using the existing BEB algorithm. We also investigate three other backoff schemes - exponential increase exponential decrease (EIED), exponential increase linear decrease (EILD) and exponential increase multiplicative decrease (EIMD). From simulation results, it is found that the EIED, EILD, EIMD perform better than the BEB for higher loads. It shows that the EIED, EILD, EIMD have better throughput and lower delay than the BEB. The EIED outperforms the other schemes in terms of throughput, delay and energy for the higher loads.</p>

Implementation of Energy Efficiency Based on Time Scheduling to Improve Network Lifetime in Wireless Body Area Network (WBAN)

ZigBee applications of IEEE 802.15.4 Wireless Sensor Network (WSN) with Low Rate Wireless Personal Area Network (LR-WPAN) can be integrated with e-health technology Wireless Body Area Network (WBAN). WBAN are small size and can communicate quickly making it easier for people to obtain information accurately.WBAN has a variety of functions that can help human life. It can be used in the e-health, military and sports. WBAN has the potential to be the future of wireless communication solutions. WBAN use battery as its primary power source. WBAN has limited energy and must be able to save energy consumption in order to operate for a long time. In this study, we propose a method of time scheduling called cycle sleep period (CSP) as WBAN solutions to save energy and improve energy efficiency. The CSP method is implemented in the real hardware testbed using sensor e-health includes temperature body and current sensor. We compared the performance of CSP method with duty cycle management (DCM) time scheduling-based and without using time scheduling.From the measurement results, our proposed idea has decreasingenergy consumption.Keywords: WSN, LR-WPAN, WBAN, e-health, Time Scheduling

Firefly-Inspired Algorithm for Data Similarity Aware Node Clustering in Low Rate Wireless Personal Area Network

Firefly-Inspired Algorithm for Data Similarity Aware Node Clustering in Low Rate Wireless Personal Area Network

Adaptive GTS Allocation Scheme with Applications for Real-time Wireless Body Area Sensor Networks

The IEEE 802.15.4 standard not only provides a maximum of seven guaranteed time slots (GTSs) for allocation within a superframe to support time-critical traffic, but also achieves ultralow complexity, cost, and power in low-rate and short-distance wireless personal area networks (WPANs). Real-time wireless body area sensor networks (WBASNs), as a special purpose WPAN, can perfectly use the IEEE 802. 15. 4 standard for its wireless connection. In this paper, we propose an adaptive GTS allocation scheme for real-time WBASN data transmissions with different priorities in consideration of low latency, fairness, and bandwidth utilization. The proposed GTS allocation scheme combines a weight-based priority assignment algorithm with an innovative starvation avoidance scheme. Simulation results show that the proposed method significantly outperforms the existing GTS implementation for the traditional IEEE 802.15.4 in terms of average delay, contention free period bandwidth utilization, and fairness.

A Fast Handoff Scheme for Streaming Service in Wireless Sensor Networks

The IEEE 802.15.4 standard is a rapidly growing technology for short-range communications and low rate Wireless personal area networking. The standard has been widely accepted as the de facto standard for wireless sensor network (WSN) because of its low cost deployment and remarkable applications. The mobility management in the existing WSN has highly suffered from different issues like high packet loss and delay because the current mobility management in IEEE 802.15.4 lacks the support of handover management for real-time streaming applications. In this paper, we propose a new fast handoff mechanism which eradicates the scanning delay. The proposed scheme uses the information of link quality (LQ) of the neighboring coordinators (COs), and on the basis of this information it selects an appropriate CO for handoff. The proposed scheme is evaluated through extensive simulations which show its strength and accuracy in the context of switching of high streaming data from one CO to another.

System evaluation of a practical IEEE 802.15.4/4e/4g multi‐physical and multi‐hop smart utility network

This study evaluates the performance of a practical IEEE 802.15.4/4e/4g low-rate (LR) wireless personal area network (WPAN) with multiple physical (PHY) layers and multi-hop capabilities for smart utility networks, machine-to-machine networks and other advanced sensor networks. The proposal includes realistic design considerations addressing demands of practical applications, country-specific regulatory requirements and technical specification in international standards. A cross-layer open system interconnection model from the application, transport, network, medium access control, down to the multiple PHY layers is constructed based on the specification in IEEE 802.15.4 LR-WPAN and other layer-specific standards. Employing the cross-layer model, extensive computer simulations were conducted to investigate the performance of the LR-WPAN system in this application domain. As a result, the authors have successfully verified the simulated achievable average throughput in both PHY layer designs, multi-rate and multi-regional frequency shift keying (MR-FSK) and multi-rate and multi-regional orthogonal frequency division multiplexing (MR-OFDM) with the theoretical throughput by calculation. Secondly, in a multi-PHY environment with the presence of 30 interferer devices, throughput degradation of the victim system is observed within 30%. Furthermore, when interferer devices transmit frames with interval beyond 1 s, the degradation to the victim system becomes negligible. Thirdly, MR-FSK PHY has a simpler design with higher energy-efficiency, whereas MR-OFDM PHY is more complicated with more resilience to interference. They have found an interference tolerance capability difference of 15 dB between the MR-FSK and MR-OFDM systems. Fourthly, comparing with their single-hop counterparts, multi-hop systems have lower average throughput in MR-FSK by 25% and MR-OFDM by 10%. Finally, comparing with networks with periodical beacon transmissions, asynchronous networks have more inferior average throughput of 20% in MR-FSK and 3% in MR-OFDM, with the advantage of longer battery lifespan.

Comparative performance analysis of IEEE 802.15.4 in WSN using NS2

Wireless Sensor Networks (WSNs) are type of network which is mainly deployed to those areas where infrastructure network is unavailable and where people cannot reach easily. To those areas sensors are deployed to collect information about the environment. Since sensors are run by battery power, long time use of sensors to those remote areas, is one of the main challenges for WSN. To deal with long time use of battery power, low power consumption technique is used. IEEE 802.15.4 standardization is used for Low Rate Wireless Personal Area Network (LRWPAN). To get a lesser amount of consumption of power, few parameters of IEEE 802.15.4 are changed in our proposed strategy. At last comparison of proposed strategy and IEEE 802.15.4 is made where proposed strategy performs well for low power consumption.

A Mac Protocol Implementation for Wireless Sensor Network

IEEE 802.15.4 is an important standard for Low Rate Wireless Personal Area Network (LRWPAN). The IEEE 802.15.4 presents a flexible MAC protocol that provides good efficiency for data transmission by adapting its parameters according to characteristics of different applications. In this research work, some restrictions of this standard are explained and an improvement of traffic efficiency by optimizing MAC layer is proposed. Implementation details for several blocks of communication system are carefully modeled. The protocol implementation is done using VHDL language. The analysis gives a full understanding of the behavior of the MAC protocol with regard to backoff delay, data loss probability, congestion probability, slot effectiveness, and traffic distribution for terminals. Two ideas are proposed and tested to improve efficiency of CSMA/CA mechanism for IEEE 802.15.4 MAC Layer. Primarily, we dynamically adjust the backoff exponent (BE) according to queue level of each node. Secondly, we vary the number of consecutive clear channel assessment (CCA) for packet transmission. We demonstrate also that slot compensation provided by the enhanced MAC protocol can greatly avoid unused slots. The results show the significant improvements expected by our approach among the IEEE 802.15.4 MAC standards. Synthesis results show also hardware performances of our proposed architecture.

Examine the Performance of different Topologies using Opnet 14. 5 in ZigBee Sensor Network

This research work is implemented in ZigBee using IEEE 802. 15. 4 protocol stack, it is most widely used technique in wireless sensor network for low rate wireless personal area network. In this paper three topologies are used i. e. mesh, tree and hybrid topology. The hybrid topology is implemented by using the combination of mesh and tree topology. The data-based setup is done by changing mobile percentage of nodes. The performance of these topologies is measured using parameters throughput, MAC delay, DTR and DTS. The results quantify that hybrid topology is best among other two topologies as it provides high throughput ,high DTR and DTS. The simulation is done by OPNET modeler 14. 5.

IJIREEICE - Electrical, Electronics, Instrumentation and Control

Wireless sensor networks represent a key technology enabler for enhanced health care and assisted living systems. Recent standardization efforts to ensure compatibility among sensor network systems have produced the IEEE 802.15.4 standard, which specifies the MAC and physical layer behaviour. Energy and network life time are two critical factors for WSN performance. IEEE 802.15.4 is a standard used for low data rate Wireless Personal Area Networks (WPANs). Medium Access Control layer (MAC) of IEEE 802.15.4 plays an important role in the performance of Wireless Sensor Network (WSN). The unique feature of this MAC layer is the superframe structure, which allows devices to access channels in a Contention Access Period (CAP) or Collision Free Period (CFP) and use beacon based synchronization mechanism. In this paper, we propose a cross-layer framework to prolong the network lifetime, to improve the energy and to lower the latency of WSNs based on the IEEE 802.15.4/ZigBee standards. To cover all the scenarios, we have considered hierarchical topology and peer to peer beacon enabled network. The performance metrics are evaluated using simulation results.

Implementation of the Adaptive CSMA-CA Algorithm Based on Traffic Load

IEEE802.15.4 is a standard designed for low rate wireless personal area network. For its MAC protocol adopts the competition method to share wireless channel, collisions between ending devices are unavoidable and lead to retransmissions, consuming more energy. As traffic load becomes heavier, collisions and retransmissions are more serious. The focus of this paper is to achieve dynamic-parameter CSMA-CA algorithm based traffic load in IEEE 802.15.4 and measure the performance of modified IEEE802.15.4 in some aspects (packet delivery rate, collision rate, collision rate and average MAC delay). Different from previous papers, it analyzes the performance of the algorithm in direct data transmission and respectively executes simulations both including and excluding hidden-terminal (HT) problems.