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PurposeRF transceiver module is considered a vital part of any wireless communication system. This module consists of two important parts the RF transceiver and analog-to-digital converter (ADC). Usually, both these parts – RF transceiver and ADC – are used to enhance the perspective of size and power. The data processing in 4G communication makes hurdles and need research attention to make it faster and smaller in size. Accuracy and fast processing are the critical challenges in the modern communication system.Design/methodology/approachAfter theoretical and practical investigations, this research work proposes key new techniques for the RF transceiver module. These techniques will make RF transceiver small, power-efficient and on the other hand, make dual SAR-ADC more effective as well. The proposed design has no intermediate frequency where the RF transceiver is reduced its major blocks from five to four, which includes crystal oscillator, phase lock loop, power amplifier and low noise amplifier. Moreover, the shared circuitry is introduced in the architecture of the SAR-ADC for the production of dual outputs, specifically in bootstrapped switch and comparator.FindingsThe miniaturized RF transceiver and SAR-ADC are well tested separately before the plantation on the printed circuit board (PCB). The operating voltage and frequency of the RF transceiver module are 1.2 V and 5.8 GHz, where the sampling rate, bandwidth and output power are 25 MHz, 200 MHz and 5 dBm, respectively. The core area of the PCB is 58.13 mm2. The bandwidth efficiency is 93% using surface acoustic wave less transmitter. The circuit is based on the library of 90 nm CMOS technology.Originality/valueThe entire circuit is highly synchronized with the input and reference clocks to avoid self-interference.

In delay tolerant networks (DTNs), nodes have intermittent connectivity patterns due to various factors such as mobility, sparse network topology, and unpredictable movement patterns. In such networks, nodes store messages, carry them along as they move and forward them opportunistically whenever an encounter occurs. In many DTN applications, such as in disaster situations and remote regions with no communications infrastructure, we can envisage a network topology formed by the mobility and contact pattern of people carrying their mobile devices. The social behavior of people (nodes) in Spatio-temporal dimensions governs the formation of such a topology. To improve data dissemination in such networks, several works have proposed to utilize social-aware metrics for the selection of relays. However, existing routing protocols for DTNs may perform poorly in the scenarios in which nodes are localized in multiple small regions, and the topology is sparse such as in co-located villages in remote regions with no communication infrastructure. This work proposes a Cooperative mobile throwbox-based routing protocol (CMTR) for social-aware DTNs. In CMTR, static and mobile ThrowBoxes (TBs) are deployed to improve the efficiency of a DTN. The static and mobile TBs cooperatively relay data to enhance network efficiency. Performance evaluation via simulations in ONE simulator shows that CMTR improves the data delivery ratio, delays, and energy efficiency as compared to Epidemic routing and Bubble Rap routing schemes.

International audience; Information-Centric Networking (ICN) has been proposed as one of the future Internet architectures. It is poised to address the challenges faced by today's Internet that include, but not limited to, scalability, addressing, security, and privacy. Furthermore, it also aims at meeting the requirements for new emerging Internet applications. To realize ICN, Named Data Networking (NDN) is one of the recent implementations of ICN that provides a suitable communication approach due to its clean slate design and simple communication model. There are a plethora of applications realized through ICN in different domains where data is the focal point of communication. One such domain is Intelligent Transportation System (ITS) realized through Vehicular Ad hoc NETwork (VANET) where vehicles exchange information and content with each other and with the infrastructure. To date, excellent research results have been yielded in the VANET domain aiming at safe, reliable, and infotainment-rich driving experience. However, due to the dynamic topologies, host-centric model, and ephemeral nature of vehicular communication, various challenges are faced by VANET that hinder the realization of successful vehicular networks and adversely affect the data dissemination, content delivery, and user experiences. To fill these gaps, NDN has been extensively used as underlying communication paradigm for VANET. Inspired by the extensive research results in NDN-based VANET, in this paper, we provide a detailed and systematic review of NDN-driven VANET. More precisely, we investigate the role of NDN in VANET and discuss the feasibility of NDN architecture in VANET environment. Subsequently, we cover in detail, NDN-based naming, routing and forwarding, caching, mobility, and security mechanism for VANET. Furthermore, we discuss the existing standards, solutions, and simulation tools used in NDN-based VANET. Finally, we also identify open challenges and issues faced by NDN-driven VANET and highlight future research directions that should be addressed by the research community.

The device-to-device (D2D) enabled cloud radio access network (C-RAN) is considered as a promising network model which provides high data rate and energy efficiency. In this paper, we formulate a joint mode selection, subchannel assignment (SA), power allocation (PA) and remote radio head (RRH)-association problem in D2D enabled single carrier frequency division multiple access based C-RAN in the uplink. This problem is mixed-integer non-linear problem which is extremely difficult to solve in its original form. To solve this problem, we propose an iterative technique which solves this problem in two stages; mode selection stage and joint SA, PA and RRH-association (SAPARA) stage. For mode selection, a link quality based technique is presented while, for joint SAPARA, we developed an iterative technique that solves this this problem in three steps such that SA and PA are carried out in the first and second step, respectively, while RRH-association is performed in the third step. Our results show the efficiency of the presented techniques.

In the absence of Internet connectivity, a content-centric opportunistic network can be established by mobile human-held devices. However, to save battery, buffer, and bandwidth resources, device carriers may selfishly disable their delay-tolerant networking (DTN) application when communication is not desired. Consequently, the network performance will degrade as the majority of the data forwarding protocols for the DTNs are designed assuming cooperative relaying by nodes. To inculcate cooperation among the otherwise selfish communicating nodes, we propose an incentive-aware pricing game for interest-based social-aware forwarding in the DTNs. We formulate the pricing game between nodes as the Rubinstein Bargain model to enhance content distribution in DTNs. The communicating nodes decide the pricing and the cooperation level based on the following three parameters: (1) remaining battery level, (2) their social strength, and (3) message worth. Moreover, to enhance content distribution of large size messages in such networks, the proposed algorithm enables nodes to share information in a peer-to-peer fashion. Performance evaluation shows that the proposed algorithm effectively increases the distribution ratio of complete files, reduces their data delivery delays, and mitigates the selfish behavior of nodes.

One of the primary causes of mortality among women aged 20–59 worldwide is breast cancer. Early detection and getting proper treatment can reduce the rate of morbidity of breast cancer. In this paper, we proposed a framework which combines machine learning and computational intelligence-based approaches in e-Health care service as an application of the Internet of Medical Things (IoMT) technology, for the early detection and classification of malignant cells in breast cancer. In the proposed approach, the detection of malignant cells is achieved by extracting various shapes and textured based features, whereas the classification is performed using three well-known classification algorithms. The most innovative part of the proposed approach is the use of Evolutionary Algorithms (EA) for the selection of optimal features, which reduces the computational complexity and accelerates the classification process in cloud-based e-Health care service. Similarly, an ensemble based classifier is used to select the best classifier by adopting the majority voting technique. The performance of the proposed approach is validated through experiments on real data sets which provide an accuracy of 98.0% in the detection and classification of malignant cells in breast cytology images.

Broadcasting is an important phenomenon, because it serves as simplest mode of communication in a network, via which each node disseminates information to their neighboring nodes simultaneously. Broadcasting is widely used in various kind of networks, such as wireless sensor networks, wireless networks, and ad-hoc networks. Similarly, in cognitive radio networks (CRNs), broadcasting is also used to perform many tasks including neighbor discovery, spectrum mobility, spectrum sharing, and dissemination of message throughout the network. The traditional approach that has been used as broadcasting in CRNs is simple flooding in which a message is disseminated in the network without any strategy check. Simple flooding can cause major setbacks in the network, such as excessive redundant rebroadcasts, and collision drops which collectively are termed as broadcast storm problem. To reduce the effects of broadcast storm problem in wireless networks, we propose and compare four broadcasting strategies for cognitive radio networks in this paper. These four strategies are: (1) probability based, (2) counter based, (3) distance based, and (4) area based. Extensive NS-2 based simulations are carried out on different threshold values for each broadcasting strategy. After experimental evaluation, it is demonstrated that counter based broadcasting surpasses other broadcasting strategies by achieving maximum delivery ratio of 60% and by decreasing redundant rebroadcasts and collision drops up to 44 and 37% respectively.

Throwboxes are small inexpensive wireless storage devices which act as relays, i.e., intermediate nodes between source and destination in wireless networks. A number of throwbox placement techniques are proposed in the literature for different networks like delay tolerant networks (DTNs). Data forwarding opportunities in DTNs are limited due to intermittent connectivity of nodes which reduces network performance. Throwbox deployment in DTNs can improve delivery ratio, delays, control overhead and thus lifetime of a network consisting of resource stringent mobile nodes. However, in order to maximize benefit of deploying throwboxes, a number of factors need to be carefully taken into account like their cardinality, placement criteria, buffer management, network topology, mobility characteristics of nodes, application requirements, and cooperation of throwboxes among themselves and with other nodes. In this paper, we present a comprehensive survey on throwbox placement in DTNs. First, we discuss various applications of DTNs. Then, we review throwbox placement techniques followed by the affect of buffer capacity on network performance. Next, we analyze the mobility aspect of throwboxes and discuss how it can influence performance. Furthermore, we review existing literature based on the number of throwboxes to be deployed. We then discuss how cooperation between throwboxes can enhance performance. Finally, we present issues, challenges and future research directions relevant to throwbox placement in DTNs.

Advanced metering infrastructure (AMI) is becoming a vital part of utility distribution networks, allowing the development of smart cities. AMI consists of smart electric, gas, and water meters, and the devices are very limited in terms of battery, processing power, and memory. The deployment and operational needs of energy-constrained network infrastructures in smart water and gas metering systems require the use of routing mechanisms that consider energy consumption, minimize energy use, and prolong network lifetime. An efficient routing metric is needed for energy-constrained devices. In this paper, we propose an energy- and congestion-aware routing metric for smart meter networks to be deployed in smart cities. The proposed metric is an adaptive parent node selection mechanism that considers the residual energy and queue utilization of neighboring nodes. Minimizing power consumption will enhance network lifetime. The proposed scheme was evaluated with the Cooja Simulator 3.0 using random and grid topology. The simulation results show greater network performance in terms of average power consumption and packet delivery ratio.

Requirement for formation of collaborations has been on increase for the software development industry, especially for smaller to medium sized firms, due to rapid technological advancements, requirements for diversified skills, ever enhancing demands for innovation and fierce competition. Collaborative product development in an alliance enables the firms to benefit from each other's diversified skills and the experience as a result of which they can develop products more rapidly and of better quality as well resulting in a higher payoff. Also, the development costs decrease. However, to avoid undesired results, selection of an appropriate partner firm for collaboration is of utmost importance keeping in view the objectives of alliance formation of both the strategic partners. One-way partner selection techniques available in the literature are impractical as they enable a firm to rank potential partners only from its own perspective while ignoring their objectives. This problem is addressed by the two-way partner selection techniques, however, they either ignore the payoff distribution criteria or the proposed criteria is unfair. More importantly, existing techniques consider that firm collaborate only with the objective to enhance their financial payoff which might not always be the case. The fact that collaborating firms may have one but different objectives for collaboration, or, each may have multiple objectives is largely neglected. To address the scenarios in which firms may collaborate due to multiple and possibly different objectives, this work proposes a bi-objective game-theoretic model that enables a firm to select an appropriate partner based on the individual preferences of both on the following two objectives: 1) learning and 2) financial revenue. Moreover, this model calculates the pay-off that each firm should get whether only monetary, only in the form of learning or both. The calculation of payoff share is based on the following parameters: 1) individual goals of collaboration of partner selecting firms on the said two objectives, 2) their level of cost contribution, 3) cooperation ratio and 4) knowledge investment difference. Comprehensive analysis of various scenarios is done for the proposed Nash Bargaining payoff distribution model to find the optimum strategy of collaborating firms for each scenario.

In wireless sensor networks, transceiver's utilisation should be minimised as it is the largest power consuming component of a wireless sensor node. In this study, the authors propose a distributive topology-control algorithm which minimises network's power consumption by allowing the non-relay nodes in the data dissemination tree to switch-off their respective transceivers when communication is not desired. In this algorithm, named duty-cycle SN-multi-point relay (MPR), the sink follows a sojourn-based mobility model and it uses MPR broadcast algorithm for broadcasting its periodic sink location update packets to the network which results in a tree consisting of relay/MPR and non-relay/non-MPR nodes. Duty-cycle SN-MPR algorithm minimises power consumption by allowing the non-relay nodes to switch-off their transceivers in each sink sojourn round. Moreover, all nodes switch-off their transceivers when the sink starts moving to its next sojourn position. Performance evaluation through simulations in network simulator 2 show that the proposed algorithm efficiently minimises the network's power consumption and also offers a better load distribution which helps in increasing the network lifetime.

A smart grid has recently gained significant attention as it is an important direction of power system advancement. The integration of renewable energy (RE) resources to the power system and the reduction of energy losses need an efficient and low-cost communication infrastructure. Cognitive radio sensor networks (CRSN) can be integrated in a smart grid to meet these challenges. CRSN is a new paradigm of research where the best of wireless sensor networks (WSN) and cognitive radios (CR) is combined. The sensor networks monitor a physical parameter and the measures value is transmitted using the cognitive radio. Thus, CRSN can be used for realizing the sensing and communication part in a smart grid network. In this paper, a smart grid network is proposed using CRSN for implementing it in the remote areas of Pakistan. The service coverage map is taken from the Pakistan Telecommunication Authority (PTA) website that regulates the spectrum band in Pakistan. This can be used in developing countries to realize a cost effective smart grid for integrating the renewable resources and for reducing energy losses.

The present research describes a modified sol–gel technique used to obtain nano-crystalline lead zirconate titanate (PZT) powders by using triethanolamine (TEA) as a polymerizing agent. The metal ions chemically interacted with TEA in the precursor sol and gel under refluxing conditions. Drying and aging treatments led to development of a precursor–polymeric gel network. A single-phase perovskite structure was formed at 470°C. The PZT gel and powders were characterized by using X-ray diffraction, simultaneous thermal analysis, and Fourier transform infrared spectroscopic techniques. The nano-crystalline morphology was examined by using a transmission electron microscope (TEM). The average particle size determined from TEM was less than 15 nm.

Wireless sensor networks (WSNs) find applications in the industrial automation where periodic and sporadic events occur. The combined propagation of information generated by periodic and sporadic events from a sensor node to an actuator node is challenging due to random nature of sporadic events, particularly, if the deadlines are hard. The IEEE 802.15.4 standard provides the basis for a real-time communication mechanism between neighboring nodes of the WSN at the media access control layer. However, the standard does not address such communications over multiple hops. To support the industrial applications with such requirements, this work proposes a novel online control protocol that exploits the basis provided by the IEEE 802.15.4 standard. The proposed control protocol ensures that a given offline sporadic schedule can be adapted online in a timely manner such that the static periodic schedule has not been disturbed and the IEEE 802.15.4 standard compliance remains intact. The proposed protocol is simulated in OPNET. The simulation results are analyzed and presented in this paper to prove the correctness of the proposed protocol regarding the efficient real-time sporadic event delivery along with the periodic event propagation.

In this chapter, the authors provide a comprehensive review of broadcasting and channel selection strategies for wireless cognitive radio networks. In the beginning, some applications of the data dissemination in wireless cognitive radio networks are discussed to highlight their importance and utility. Next, the authors provide a detailed classification of broadcasting protocols in light of the existing literature, and the pros and cons of each classified category are discussed. Afterwards, the data dissemination is briefly discussed in the context of multi-channel environments and the related issues are highlighted. Then, the authors discuss the challenges of data dissemination in cognitive radio networks, followed by the classification of channel selection strategies along with their advantages and disadvantages for various classes of applications. In the last part, the authors conclude this chapter with open research issues that need to be addressed to provide efficient channel selection and data dissemination strategies in cognitive radio networks.

Several recent works propose mobile sink based data gathering approaches to distribute energy consumption in Wireless Sensor Networks. However, mobility based algorithms require the sink to periodically update its location to the network to ensure multi-hop connectivity. This additional information increases the control traffic overhead, and thus energy consumption also increases. In this paper, we propose a distributive energy efficient sink location update mechanism for mobile sink WSNs, along with a preemptive buffering data collection technique. This sink location update mechanism combines MPR based broadcast [2] algorithm with a distributed local repair mechanism, whereby, sensor nodes dynamically control the scope of sink location update messages. In preemptive buffering mechanism, sink's neighbor nodes act as temporary data collection points, referred as roots, to prevent data loss when sink moves out of their vicinity. We show by simulations that our proposal effectively reduces the energy consumption and data losses of the network.

Wireless Sensor Networks (WSN) are applicable in vast range of applications and depending on the application the sink could be mobile or stationary. Sink mobility has been shown to improve network lifetimes [1], however mobile sink has to periodically update network about its changing position. This control traffic is non-negligible for low power, limited capacity sensors and induces energy consumption problem in a wireless sensor network. Designing efficient broadcast techniques which ensure network wide updates with minimum overhead is an utmost necessity. This work proposes a distributed sink location update and a tree-based data gathering mechanism for mobile sink WSNs called SN-MPR. This mechanism uses a Multi-Point Relay (MPR) forwarding [2] for sink location updates and queries. The scope of the MPR broadcast based sink location updates is dynamically controlled by sensor nodes whereby sensor nodes forward a new sink update messages only if sink mobility has affected their path towards the sink. Simulation results show that SN-MPR reduces energy consumption of the network without affecting data dissemination efficiency.

Mobile sink Wireless Sensor Network (MSWSN) has recently received a lot of attention from the research community. Its appealing characteristics of providing longer network lifetimes, delay optimizations and the flexibility to adapt dissemination strategies according to applications' requirements have proved to be more efficient. Numerous mobile sink based data dissemination strategies have been proposed. This work presents state of the art literature review on MSWSN data dissemination strategies. Issues and flexibilities that did not exist with static sink WSN have been discussed. A classification of available data dissemination strategies and their pros and cons has been discussed.

International audience; The use of Fish eye scoping has been introduced to reduce the overhead of the OLSR routing protocol. This simple method is based on reducing the scope (TTL) of some topology updates, thus giving routers a precise view of their close neighborhood and a more and more approximate view of farther nodes. Fish Eye OLSR (OFLSR) has been showed to have excellent scaling properties and low network overhead. However, if deployed in relatively sparse networks, this scoping limitation of topology updates can result in long living routing loops, thus limiting the potential applications of such mechanisms in some practical wireless mesh networks. In this paper, we address the transient mini-loop problem due to fisheye scoping. We first analyze the occurrence of mini-loops. We discuss potential solutions and propose a pragmatic and distributed off-line heuristic, which allows each router to compute “safe” scope for topology updates. With our method, every mesh router calculates in advance the minimum TTL value that avoids mini-loops at the “scope” boundary --- optimal scope that will be set for generating topology update message whenever a neighbor link lost is detected. Simulations show that the proposed algorithm drastically improves safety of Fish Eye OLSR while still retaining its scaling and performance properties.

Generation of the freestanding lead zirconate titanate (PZT) nanoparticles and their phase transformation behavior is investigated in this research. PZT sol-gel precursor was dried at 250°C and partially calcined at 450°C for 30min to decompose organics and bring down the free energy barrier for perovskite crystallization. Annealed at 550–600°C, sol-gel PZT powder exhibited freestanding nanocrystalline morphology. The electron diffraction pattern obtained from nanoparticles confirmed their crystallinity and perovskite phase formation. The structural characteristics were evaluated by transmission electron microscope and x-ray diffraction techniques. The average PZT nanoparticle size of 20nm was observed by transmission electron microscope and Scherrer’s method.