Secondary Users (SU) are guided by Cognitive Radio Device in identifying a channel licensed to Primary Users (PU) when it is free. Whenever PU arrives, SU shall vacate and search for the alternate band by a conditional handoff. Existing handoff methods reduce the network’s efficiency. The proposed stochastic approach under hybrid Spectrum Hand-off is (SHO) employing the Invasive Weed Optimization (IWO)

As power consumption results in greenhouse gas emissions and energy costs for operators, analyzing power consumption in wireless networks and portable devices is of crutial importance. Due to environmental effects resulted from energy generation and exploitation as well as the cost of surging energy, energy-aware wireless systems attract unprecedented attention. Cognitive Radio (CR) is one of the optimal

The seamless vertical handoff from a wireless local area network (WLAN) to a cellular system yet poses a big challenge. While serving by a WLAN, a mobile node (MN) may enter a region with a low data rate before completing a handoff towards a cellular network. To maintain quality of service, a large amount of WLAN bandwidth must be allocated to compensate for the weakness of MN link. However, this mechanism

Multiple description coding (MDC) has been an effective scheme for reliable transmission of videos over error prone networks but requires higher data rates. Recently, perceptual video coding schemes are able to encode videos at a lower data rate, but with the same perceived decoding quality. Such schemes exploit human visual system (HVS) properties to encode videos. Although HVS characteristics have

To check students’ daily language learning tasks and give students corresponding reasonable scores based on their daily behavior is hard for teachers. The existing online language learning systems are vulnerable and easy to be modified by teachers or system managers. Blockchain can provide immutable and trusted storage service and automatic calculation service. Therefore, a blockchain-based online

Adaptive communication for is one of the hottest areas of research in the telecommunication systems including wireless broadcast systems. This is primarily accomplished for sake of boosting the transmission throughput with enhanced quality of service and ideal link utilization. In adaptive communication, various radio transmission parameters like modulation symbol, code-rate and power etc. are carefully

This paper considers simultaneous wireless information and power transfer enabled full-duplex multi-user multiple-input multiple-output cognitive networks. By taking into account imperfect channel state information (CSI) of the links toward primary users (PUs), this paper aims to simultaneously optimize two design objectives, namely the achievable sum-rate and sum harvested energy in the secondary

The new revolution in computing and wireless communications technologies led to Internet of Things (IoT). Information collection scheme performs an important role for energy efficient utilization and latency awareness in IoT environments. The enhancement of an effectual information collection scheme is crucial to improve the overall performance of the internet of things applications. In this paper

Traditional multi-criteria decision making (MCDM) algorithms are used in the handover of user equipment (UE) in an Ultra Dense Network (UDN). UDN refers to the increased density of the Radio Access Technologies (RATs) in a region which leads to the overlapping of the areas covered by individual RATs. MCDM algorithms such as TOPSIS, PROMETHEE and SAW are used to initiate handovers between these RATs

The importance and applications of sensor networks have grown significantly in recent years. These networks are implemented in an ad-hoc manner, where messages pass through multiple intermediate nodes until they reach a central node (sink node). Depending on the type of application, the message loss rate can compromise its performance and even make its use unfeasible. The objective of this work is

The Cloud is a new computing paradigm that has experienced exponential growth in recent years. Therefore, success in the cloud services industry can be a challenge, as satisfying both cloud service users and providers is challenging. Cloud users expect to receive a higher service quality with the lowest possible prices. On the other hand, cloud service providers need to maximize their revenues by utilizing

Inter-Cell Interference (ICI) could affect the performance of the LTE-Advanced (LTE-A) system and can be evaluated according to the user’s Signal to Interference and Noise Ratio (SINR). Owing to this, the power and frequency allocation schemes can be utilized in order to attain an optimum trade-off within the obtained SINR and the resulting interference. In this study, power allocation was integrated

Labeling diversity (LD) is a well-known technique proposed for multi-antenna Wireless local area network (WLAN) applications . In this paper, we propose LD for three-terminal cooperative communication schemes i.e., Decode and Forward (DF) and Coded-cooperative (CC) schemes with each terminal using a single antenna for transmission. The Boosted space-time codeword is jointly constructed by source and

The directional transmission of millimeter wave (mmWave) beam is applied in the satellite cluster, which can efficiently avoid the interference problem caused by the satellites working in the same frequency band. However, due to the dynamic change of the satellite cluster topology and the randomness of the message transmitted by satellite, there will still be interference. In this paper, in terms of

In order to more accurately evaluate or calibrate the electronic torsional vibration test analyzer and analysis method, a torsional vibration signal generator is developed in the present study. The developed device generates a tooth pulse interval sequence based on the inverse solution of the shaft torsional equation. Moreover, a single-frequency signal, inter-harmonic signal, time-varying harmonic

A polarization multiplexed all-optical orthogonal frequency division multiplexing (AO-OFDM) system is investigated analytically and numerically, with 12.5 Gbaud symbol rate, that is compatible with the International Telecommunication Union flexible grid. We demonstrate that fast adaptive filtering is not require at the receiver and chromatic dispersion with polarization mode dispersion can be compensated

This paper studies the interference graph construction problem for device-to-device (D2D) communications underlaying cellular networks. Firstly, an improved interference graph construction method compared to the previous work in Zhang et al. (IEEE Trans Vehicular Technol 66(4):3293–3305, 2017) is proposed. The difference is mainly that, in this work the BS allocates resources for transmitting probe

The rapid growth of small cells is driving cellular network toward randomness and heterogeneity. The multi-tier heterogeneous network (HetNet) addresses the massive connectivity demands of the emerging cellular networks. Cellular networks are usually modeled by placing each tier (e.g macro, pico and relay nodes) deterministically on a grid which ignores the spatial randomness of the nodes. Several

Confidentiality and integrity are fundamental requirements when transmitting and storing data. In order to guarantee the confidentiality and integrity of speech signal, we present a novel wateRmarking scheme for Encrypted sPeech AuthenticatIon with Recovery (REPAIR) scheme. In REPAIR, an encryption algorithm is first designed based on a hyper-chaotic method to improve the confidentiality of the original

In the current era of IoT, home appliances like dishwashers, washing machines, and coffee makers, etc. are being equipped with internet access and sensing resources to provide autonomous or semi-autonomous functionality to its users. It is foreseeable that these appliances will soon be capable to collaborate by sharing their capabilities enabling dynamic operations as per the context and user preferences

This paper studies the energy efficiency (EE) optimization problem in multiple-user multiple-input–multiple-output heterogeneous wireless powered communication network (HWPCN) in which the users in small cells can harvest energy from the small cell base stations in downlink and use harvested energy for uplink transmission. We consider the joint design problem of wireless energy transmission and wireless

In order to implement the interweave cognitive radio solutions, the research for finding sparsely utilized spectrum bands has revealed the VHF and UHF television broadcast bands, known as television white spaces (TVWS) as the foremost candidate. The TVWS quantification and throughput analysis conducted via several measurement attempts and field trials uncover various facets of the TVWS spectrum measurement

RFC 5180, the IPv6 update of RFC 2544, declared IPv6 transition technologies out of its scope. RFC 8219 defined a benchmarking methodology for IPv6 transition technologies including stateless NAT64 (more properly called SIIT) in the category of single translation solutions. Whereas several research papers have dealt with the performance of different stateful NAT64 implementations, none of them used

Authentication has strong impact on the overall security model of every information system. Various authentication techniques are available for restricting the access of unauthorized users to the enterprise scale networks. IEEE 802.1X defines a secure and reliable authentication framework for 802.11 WLANs, where Extensible Authentication Protocol (EAP) provides the base to this architecture. EAP is

This paper presents a Broadcast and Reliable Coverage based Efficient Recursive Routing (BRCER) in Large-Scale Wireless Sensor Networks for Event-Driven Applications with Mobile Sinks (MSs). For data routing in the network, the proposed protocol updates the connectivity list by using local broadcast and multicast announcement. Instead of broadcasting in the whole network, the local broadcasting is

Drivers can be provided with several beneficial services associated with video streaming in a vehicular ad-hoc network (VANET). Given the dynamic topology and high mobility of VANETs, a single path cannot support the required quality of service (QoS). To maximize global QoS metrics, a two-path model is proposed based on a disjoint algorithm to forward sub-streams over diverse paths from the transmitter

We explore the RIPless theory for the analysis of single snapshot DOA estimation with uniform linear array using the compressed sensing technique. Starting with a sparse signal recovery model constructed for single snapshot DOA estimation, we prove the isotropy property and incoherence property are fulfilled for the estimation problem. A vital proposition is obtained using the RIPless theory, which

The IPv6 routing protocol for low-power and lossy networks (RPL) is the standard routing protocol for IPv6 based low-power wireless personal area networks (6LoWPANs). In RPL protocol, DODAG information object (DIO) messages are used to disseminate routing information to other nodes in the network. A malicious node may eavesdrop DIO messages of its neighbor nodes and later replay the captured DIO many

In this paper, we propose a new Adaptive Cooperation (AC) protocol for Free Space Optical (FSO) communications. Two versions of the protocol are presented. The first protocol uses the Instantaneous Signal to Noise Ratio (ISNR) to activate the relay only when the corresponding instantaneous throughput is better than that of the direct link. The second protocol uses the Average SNR (ASNR) to activate

Device-free passive wireless indoor localization has attracted great interest due to the widespread deployment of Wi-Fi devices and the rapid growth in demand for location-based services. In this paper, we propose a novel device-free passive wireless localization system with a weighted transferable discriminative dimensionality reduction method (termed TLLOC). It utilizes the channel state information

Crowdsourcing application, deemed as a key evolution on the way to vehicular networking, has great potential to provide real-time services. However, existing cloud-based vehicular networking cannot support real-time data transmission with wasting massive bandwidth resources. This paper studies the crowdsourcing application in edge-assistant vehicular networking. To improve the real-time demand of data

Network slicing technology is a core part of 5G network, which enables users to access the suitable network on demand and increases the flexibility of network resources through appropriate network configuration. However, the group users in dynamic 5G network slices face communication security threats (impersonation attack, network monitoring, identity leakage, etc.). Group key agreement (GKA) protocol

In this paper, the impact of varying path loss exponent (PLE) on user association probability, decoupled uplink coverage probability as well as decoupled uplink average spectral efficiency in downlink uplink decoupled (DUDe) multi-tier heterogeneous networks, is investigated. We investigate the effect of the difference in path loss exponents in both macro and small cell environments over uplink network

We present a new fast polling algorithm (FPA) in a wireless mesh network (WMN) for Narrowband Internet of Things systems using multi-hop WMNs. We focus on wireless networks with stationary IoT remote telemetry units (IoT RTU), such as wireless network monitoring. The goal of the new FPA is to minimize the time required for supervisory control and data acquisition center to poll all RTUs one by one

An efficient and fair packet scheduler is very important to guaranty the cellular network quality of service (QoS). In general, classic packet schedulers follow static rules based on priorities. Unfortunately, static rules may cause unfair resource distribution. We present and analyze FuzSy, a cellular network packet scheduler based on the quality of service and fuzzy logic. Instead of following static

The Quantum-Dot Cellular Automata (QCA) is an incipient nanotechnology in contrast to the CMOS technology with appealing features like low power consumption, high speed and reduced size in implementing the architecture for the computations. QCA provides better and well-organised solution with a modern and exclusive result in performing logical computations at Nano-scale. In this paper mainly focused

Cognitive radio (CR) is introduced to efficiently and opportunistically use the limited spectrum to minimize the spectrum scarcity issues. Usually, service providers purchase the spectrum license from the policy-makers and spectrum regulator authority. The non-licensed users cannot utilize the licensed bands even though primary user is not transmitting. It sometimes results in under-utilization of

In cognitive radio networks, secondary nodes should sense the channel using spectrum sensing algorithms to detect primary activity. When primary user (PU) is idle, secondary users opportunistically transmit over this frequency hole. In this paper, we provide the detection probability (DP) of the energy detector (ED) for wireless energy harvesting systems. PU and relays harvest energy from radio frequency

In this article, we suggest a new Spectrum Sensing (SS) algorithm using Incremental Relaying (IR). In previous studies, the relays always cooperate in the SS process. However, sometimes the Signal to Noise Ratio (SNR) of the direct link between the Primary User (PU) and the Fusion Node (FN) is high and cooperation is not required. We suggest to activate the relays only when the SNR of direct link is

In this paper, we have proposed Link Pair Method (LPM) and Improved Double Cycle (IDB) method based on pre-Configured Cycles (p-cycles) for two-link failure protection in optical networks. We have compared Double Cycle (DB), IDB and LPM method on the basis of spare capacity and computation time. We have observed a reduction in the required spare capacity for IDB as compared to the DB method. We achieved

Software-defined networking (SDN) has provided a new paradigm for network management by allowing a central controller to program the underlying switches directly. However, OpenFlow, the de facto standard API for communicating with the switches, has limited visibility into the network headers, hindering innovations in the data plane and overloading the controller when a more sophisticated network application

The security rate optimization problem of a multi-antenna decode-and-forward full-duplex relay system powered by simultaneous wireless information and power transfer is studied. A system model and secure transmission scheme based on energy cooperation and cooperative jamming are presented. The full-duplex relay node works in a power splitting mode for energy collection and information decoding. Artificial

Frequency-domain contention is a new paradigm of contention that has been proposed to enhance the performance of OFDM wireless networks. In this paper, we demonstrate how frequency-domain contention schemes would fail in a wireless local area network (WLAN) due to the existence of nodes that are hidden from each other. In addition, we propose a new MAC protocol, which is called EFDC (enhanced frequency-domain

Telecom systems for ships and offshore plants used to be tools for long-distance communication in the past. Today, telecom systems combined with evolving IT ensure safety, accident prevention and cost saving for ships and offshore plants. In the future, all systems will be managed and controlled by telecom systems. Yet, the IMO and Classification Societies have neither revised nor amended the requirements

In this paper, wireless sensor network (WSN) security issue in the presence of an eavesdropper is analysed. The sensor-sink as well as sensor-eavesdropper channels are assumed to be subjected to generalized-K fading. According to the physical layer security framework, we employ round-robin, optimal sensor and cumulative distribution function-based scheduling scheme to enhance secure connection between

Rain induced attenuation prediction is considered a fundamental step in the analysis of satellite communication links for frequencies above 10 GHz, due to their major effect on the satellite communication link and services. This paper presents an approach for predicting and analysing the satellite link performance during rainfall in subtropical climate for K and Ka frequency bands. The study characterizes

In general, a concatenated RS/BCH code consists of an outer RS code and an inner BCH code with separation by an interleaver. We create a novel BCS code using a new methodology by combining an outer BCH code with an inner RS code appended by an interleaver to randomize burst errors and help the RS code in correcting the errors. Generally, BCH codes handle binary data, whereas RS codes handle non-binary

Abstract In multiapplication sharing wireless sensor networks, various application queries exhibit similarity in their spatial, temporal, and sensing attribute requirements, thus result in redundant sensing tasks. The dissemination and execution of such redundant sensing tasks cause network traffic overhead and quick energy drop of the sensor nodes. Existing task scheduling and allocation mechanisms

Abstract Intelligent transportation system is a prominent technology solution for the vehicle manufacturers in this present scenario. The manufacturers are trying to deploy an advanced system for automation through sensing. Various technologies are being used to communicate with other near-by vehicle and to sense their perspective on the road. The important problem is to share the radar and communication

Abstract Orthogonal frequency division multiplexing based cooperative system using Alamouti space–time block coding at relay node represents an alternative solution to achieve better connectivity and significant enhancement to the data rate in wireless fading channels. But, these advantages cannot be achieved without an efficient estimation of the channels which becomes more challenging for cooperative

Abstract For the underlay spectrum sharing, a primary transmitter (PT) and a secondary transmitter (ST) can transmit simultaneously to a primary receiver (PR) and a secondary receiver (SR), respectively. The transmit power of ST is strictly controlled under the performance constraint of primary system. The strong interference from PT and the weak signal from ST make the communication quality of secondary

Abstract In the Internet of Things architecture, the distributed management structure of the data center-micro data center (MDC)-intelligent terminals is the foundation for intelligent terminals accessing, real-time data interaction and data release. It is necessary to perform security level detection before intelligent terminals accessing to the MDCs, which can facilitate MDCs to understand the ability

Abstract This research article has been conducted for the efficient use of frequency spectrum in multi-RAT cellular network using dynamic spectrum refarming (DSR). For this purpose, two overlapping networks, GERAN and EUTRAN, and their voice and data traffic statistics are taken into consideration. Our investigation of hourly traffic changes in the voice service in the GERAN and the data service in

Abstract The Channel estimation in Vehicle-to-Vehicle (V2V) communications is critical due to the time-varying characteristics of the V2V channel. Hence, the authors propose a hybrid approach towards channel estimation by combining Pilot Symbol Aided Channel Estimation (PSACE), Improved Crow Search Algorithm (ICSA), and Decision Directed Channel Estimation (DDCE) by employing Weight Regularized Convolutional

Abstract The vehicle-to-everything (V2X) communications, as enabled by cellular device-to-device (D2D) links, has recently gained greater attention owing to the remarkable capacity it displays in enhancing traffic safety, effectiveness, and comfort. It is in this context that the present paper can be set, whereby a new technology is advanced, relating to the fifth generation (5G) associated D2D based

Abstract In the era of Internet-of-things (IoT), the future 5G networks are supposed to provide ubiquitous connectivity, high speed, as well as low latency and energy efficiency at low cost to billions of battery-powered wireless devices. The anticipated tremendous demand for wireless bandwidth in 5G networks calls for efficient usage of the underutilized licensed frequency spectrum that preserves

Abstract Although 4G (fourth generation) i.e. LTE (long term evolution) systems are now in use world-wide. But today’s 4G systems have some challenges left such as spectrum scarcity and energy efficiency. The prime objectives of near-by-future 5G (fifth generation) wireless communications are reliability, higher data rate, higher bandwidth, high spectrum efficiency, higher energy efficient and that

Abstract The content-centric networking depends on a forwarding information base (FIB) to forward Interest towards providers and utilizes reverse paths in a pending Interest table (PIT) to send Data back to consumers. If consumers change their locations, reverse paths may disrupt and consequently content-centric communications fail. If providers change their locations, each relevant content router

Abstract Signals from indoor access points in a wireless fidelity suffer from high attenuation as a result of the thick walls and metal structures in the multilevel-storey buildings where they are deployed. This is due to the scattering of the retransmitted signals by the thick walls and metal structures. Power line communication (PLC) technology is considered as a solution to overcoming this challenge

Abstract Future wireless networks like 5G will carry an increasingly wide variety of data traffic, with different QoS requirements. In addition to conventional data traffic generated from HTTP, FTP and video streaming applications by mobile broadband users [human-type communication (HTC)], traffic from machine-to-machine (M2M) and Internet-of-Things (IoT) applications [machine-type communication (MTC)]