Communication In Cognitive Radio Networks Research Articles

Covert Communication in Cognitive Radio Networks with Poisson Distributed Jammers

Covert Communication in Cognitive Radio Networks with Poisson Distributed Jammers

Joint spectrum sensing and D2D communications in Cognitive Radio Networks using clustering and deep learning strategies under SSDF attacks

In Spectrum Sensing and Data Falsification Attacks (SSDF), malicious Secondary Users (SUs) in Cognitive Radio Networks (CRNs) intentionally try to disrupt the global Cooperative Spectrum Sensing (CSS) decision for their self-benefit. Most existing works focus on mitigating the impact of SSDF attacks on CSS decisions. However, a small piece of work jointly studies the CSS and opportunistic data transmission under SSDF attacks in a single framework, but they have some limitations. The present work proposes joint CSS and SU data transmissions in Energy Harvesting-enabled CRNs under SSDF attacks. The present work uses the clustering strategy to isolate the malicious SUs from the honest set of SUs using reputation value and other attributes. The identified malicious and unfit SUs are restricted from opportunistic Device-to-Device (D2D) communication in CRNs. An Ensemble Learning strategy is proposed, which enhances the CSS reliability over the existing works by ∼36.91%, ∼25.00%, and ∼19.04%. Several network constraints guide the reliable SU transmissions in a hybrid framework under SSDF attacks to support the Quality-of-Services for both primary and secondary networks.

Performance Analysis of Three Spectrum Sensing Detection Techniques with Ambient Backscatter Communication in Cognitive Radio Networks

In wireless communications, the Ambient Backscatter Communication (AmBC) technique is a promising approach, detecting user presence accurately at low power levels. At low power or a low Signal-to-Noise Ratio (SNR), there is no dedicated power for the users. Instead, they can transmit information by reflecting the ambient Radio Frequency (RF) signals in the spectrum. Therefore, it is essential to detect user presence in the spectrum for the transmission of data without loss or without collision at a specific time. In this paper, the authors proposed a novel Spectrum Sensing (SS) detection technique in the Cognitive Radio (CR) spectrum, by developing the AmBC. Novel Matched Filter Detection with Inverse covariance (MFDI), Cyclostationary Feature Detection with Inverse covariance (CFDI) and Hybrid Filter Detection with Inverse covariance (HFDI) approaches are used with AmBC to detect the presence of users at low power levels. The performance of the three detection techniques is measured using the parameters of Probability of Detection (PD), Probability of False Alarms (Pfa), Probability of Missed Detection (Pmd), sensing time and throughput at low power or low SNR. The results show that there is a significant improvement via the HFDI technique for all the parameters.

Spectral efficiency maximization for IRS-assisted wireless communication in cognitive radio networks

In this paper, we consider the Intelligent reflecting surface (IRS)-assisted cognitive radio (CR) network, in which the IRS is applied to improve the spectral efficiency of secondary users. In specific, the advantages of applying IRS is double: it can not only improve the transmission rate of the secondary users, but also reduce the interference from the secondary users to the primary users, which allow the secondary users to increase the transmission power correspondingly. The original problem is formulated by simultaneously consider the maximum power limitation of the secondary users and the Quality of Service (QoS) requirement of the primary users, which expressed by the interference temperature (IT). The formulated problem is non-convex and difficult to solve directly. We apply the alternating optimization (AO) algorithm to split the original problem into two sub-problems. For the first sub-problem, we transform it into a convex problem and for the second sub-problem, we use the successive convex approximation method to obtain the corresponding results. The simulation experiments show that the performance of our proposed scheme is better than existing schemes.

On outage analysis of nonlinear radio frequency energy harvesting based cooperative communication in cognitive radio network

AbstractThe aim of this article is to investigate the outage performance of nonlinear radio frequency (RF) energy harvesting (EH) enabled decode‐and‐forward relay assisted cognitive radio network. Here, secondary transmitter (ST) can access the licensed spectrum of primary users (PUs) to send its message toward the secondary receiver and at the same time, it can support the primary communication by performing like a relay node. ST can harvest the energy from the received RF signal of primary transmitter to execute its necessary activities. The closed‐form expressions of PU and secondary user outage are derived to measure the end‐to‐end reliability of the system. The accuracy of derived expressions are also validated through the observation of simulation results. In addition to that, the performance of nonlinear EH model is also compared with respect to linear EH model.

Channel allocation and ultra-reliable communication in CRNs with heterogeneous traffic and retrials: A dependability theory-based analysis

The current research efforts on Fifth Generation (5G) of wireless communication systems have identified the need for large extent improvements in accessibility and reliability of communication services. In this respect, Cognitive Radio (CR) has been envisioned as a key 5G enabler that allows dynamic spectrum access without causing interference to licensed (primary) users and can tackle the challenge of ultra reliable communication. Channel failures, which are generally caused due to hardware and software failure and/or due to intrinsic features such as fading and shadowing, can easily result in network performance degradation. In cognitive radio networks (CRNs), the connections of unlicensed (secondary) users are inherently vulnerable to breaks due to channel failures as well as licensed users’ arrivals. To explore the advantages of channel reservation and retrial phenomenon on performance improvement in error-prone channels, we propose and analyze dynamic spectrum access (DSA) scheme by also taking balking and reneging behavior into account. Moreover, since 5G networks should comprise heterogeneous applications that may have different Quality of Service (QoS), thus the present study facilitates the arrival of heterogeneous secondary users with access privilege variations. In addition, most previous works have studied the stationary performance of CRNs, however, those may not be adequate in practice, notably when the time horizon of operations is finite. This paper investigates the transient dynamics from the perspectives of dependability theory in CRNs. Furthermore, the whole system is modeled using a multi-dimensional continuous time Markov chain (CTMC) and numerical results illustrate the potential of the proposed scheme to achieve major gains in the performance of error-prone CRNs.

Artificial-Noise-Aided Energy-Efficient Secure Beamforming for Multi-Eavesdroppers in Cognitive Radio Networks

In this article, we investigate optimal beamforming at a multiantenna primary base station (PBS) and a multiantenna cognitive base station (CBS) for energy-efficient (EE) secure downlink communication in cognitive radio networks with one single-antenna primary user (PU), one single-antenna cognitive user (CU), and multiple single-antenna eavesdropping nodes. An artificial noise transmission scheme is used by CBS to protect the data against the eavesdropping security attacks at the cost of extra power consumption. To improve the secrecy energy efficiency (SEE), we propose a SEE maximization (SEEM) scheme by exploiting the instantaneous channel state information (CSI) of the eavesdroppers under the secrecy rate (SR) constraints of the PBS-PU and CBS-CU channels, the quality-of-service requirement of the PU, and the transmit power constraint of the CBS. When the eavesdropping links’ instantaneous CSI are unknown at the legitimate transmitters (i.e., PBS and CBS), we propose another SEEM scheme based on the statistical CSI of the eavesdropping links. Since the formulated optimization problems with fractional objective functions are nonconvex and mathematically intractable, we first transform them into equivalent subtractive problems, and then, employ the difference of two-convex functions approximation method to arrive at approximate convex problems. In addition, new two-tier optimal BF algorithms are proposed. Finally, simulation results are presented to illustrate the effectiveness and performance gains of our proposed SEEM schemes over conventional SR-only maximization and EE-only maximization schemes.

Wireless transport protocol variants for cognitive radio networks

Scarce wireless resources, lead to development of cognitive radio network as a solution to unlicensed users communication in the licensed frequency band. In response to the behavior of licensed users communication, unlicensed users communication need to change from one frequency band to another band. In this communication paradigm, the performance of unlicensed users transmission control protocol gets degraded due to the features of cognitive radio network. To overcome this, several authors suggested quite a few modifications in the existing wireless transport protocol for cognitive radio network environment. This paper gives an overview of different transport protocols used for unlicensed users’ communication in cognitive radio networks.

A research survey on scheduling techniques in lte-based network and its state of art

Scarce wireless resources, lead to development of cognitive radio network as a solution to unlicensed users communication in the licensed frequency band. In response to the behavior of licensed users communication, unlicensed users communication need to change from one frequency band to another band. In this communication paradigm, the performance of unlicensed users transmission control protocol gets degraded due to the features of cognitive radio network. To overcome this, several authors suggested quite a few modifications in the existing wireless transport protocol for cognitive radio network environment. This paper gives an overview of different transport protocols used for unlicensed users’ communication in cognitive radio networks.

IDsMA: An integrated digital signature and mutual authentication mechanism for securing the cognitive radio networks

SummaryEnabling a reliable and secure communication in cognitive radio networks (CRNs) is one of the interesting and demanding research areas and these days, it is used in wide range of applications. The traditional works mainly aimed to improve the spectrum efficiency and bandwidth utilization of the CRN. Moreover, it focused on attack detection in the network for improving the reliability. Thus, this work intended to secure the CRN by considering the objectives of both attack detection and quality of service (QoS) improvement. For this purpose, an integrated digital signature and mutual authentication (IDsMA) mechanism is proposed in this paper, which incorporates the benefits of both security and reliability. Also, the Rivest‐Sharmir‐Adlemann (RSA) algorithm is utilized to encrypt and decrypt the data at the transmitter and receiver side. Here, the unique user ID is generated by the service eNodeB based on the hash function, which is validated at the server side for validating the authenticity of the user. Furthermore, the particle swarm optimization (PSO) and relevant vector machine (RVM) techniques are utilized for optimal channel selection and attack classification. The simulation results evaluate the performance of the proposed technique by using various performance measures. Also, its superiority is proved by comparing the proposed technique with the existing techniques.

Secure mmWave Communications in Cognitive Radio Networks

In this letter, the secrecy performance in cognitive radio networks (CRNs) over fluctuating two-ray (FTR) channels, which is used to model the milimeter wave channel, is investigated in terms of the secrecy outage probability (SOP). Specifically, we consider the case where a source (S) transmits confidential messages to a destination (D), and an eavesdropper wants to wiretap the information from S to D. In a CRN framework, we assume that the primary user shares its spectrum with S, where S adopts the underlay strategy to control its transmit power without impairing the quality of service of the primary user. After some mathematical manipulations, an exact analytical expression for the SOP is derived. In order to get physical and technical insights into the effect of the channel parameters on the SOP, we derive an asymptotic formula for the SOP in the high signal-to-noise ratio region of the S-D link. We finally show some selected Monte-Carlo simulation results to validate the correctness of our derived analytical expressions.

Secure communication in cognitive radio networks with untrusted AF relays

SummaryIn this paper, two underlay based cognitive cooperative radio networks, each with one secondary source (SS), one secondary destination (SD), N untrusted secondary amplify and forward relays (USAFRs), one primary transmitter, and one primary receiver (PU‐RX), are considered for evaluating the secrecy performance. The SS sends the information to the SD in two time slots via multiple USAFRs in the absence of direct link between SS and SD. In the first time slot, SS and SD transmit the message and jamming signal to multiple USAFRs, respectively. In the second slot, a selected USAFR amplifies and forwards the combined received signals to the SD. The transmit powers of the secondary nodes are chosen so as to maintain the overall interference at PU‐RX below a specified limit. The transmit power of a selected USAFR is derived using the harvested energy from the RF signals of SS and SD. Two network scenarios of eavesdropping by USAFRs are studied: in one case, all USAFRs eavesdrop; while in the second case, only the selected USAFR eavesdrops the message during forwarding of the signal and power is allocated to secondary nodes on the basis of outage threshold of primary network. We investigate the secrecy outage probability (SOP) in both of the networks under several physical parameters. Analytical framework for evaluating SOP for both the cases are given while SOP in single integration form is given for the second case. MATLAB simulation results are presented for both the cases.

A Comprehensive Review on Spectrum Management, Security and Energy-Efficient Cognitive Radio Networks

The explosive growth of mobile devices and the rapid increase in wireless services necessitate an improvement in communication techniques. This technology can boost spectrum utilization as well as meet the massive connectivity requirement to draw attention from academia and industry. Cognitive Radio Network (CRN) is an evident optimal solution in alleviating the challenges of spectrum unused potentially in wireless networks. The Secondary Users are allowed intelligently to access the sections of spectrum unused (spectrum holes) by the authorized Primary Users (PUs). The objective of this paper is to analyze channel throughput, delay, carrier aggregations, energy efficiency, and security challenges and provide research ideas to enhance the overall performance of the CRN. This review paper completely investigated the potential management of spectrum techniques, essentially in spectrum sensing, spectrum allocation, spectrum sharing, and spectrum handoff in CRN. In addition, we study the energy efficient routing techniques like network optimization frameworks in cooperative networks, protocols and different types of attack issues, approaches for handling the secure communication in CRNs. The state of art review, which deeply examines the Cognitive Radio Network providing an idea of important technology and challenges are addressed. The open research challenges related to spectrum management, energy efficient routing and security are discussed.

Secured communications in cognitive radio networks

Secured communications in cognitive radio networks

Wireless Transport Protocol Variants for Cognitive Radio Networks

Scarce wireless resources, lead to development of cognitive radio network as a solution to unlicensed users communication in the licensed frequency band. In response to the behavior of licensed users communication, unlicensed users communication need to change from one frequency band to another band. In this communication paradigm, the performance of unlicensed users transmission control protocol gets degraded due to the features of cognitive radio network. To overcome this, several authors suggested quite a few modifications in the existing wireless transport protocol for cognitive radio network environment. This paper gives an overview of different transport protocols used for unlicensed users’ communication in cognitive radio networks

Performance evaluation and system optimization of Green cognitive radio networks with a multiple-sleep mode

Cognitive radio networks (CRNs) have been emerged as a solution for realizing dynamic spectrum allocation. Green communication in CRNs will contribute to reducing emission pollution, minimizing operation cost and decreasing energy consumption. The Green CRNs would help in realizing “green spectrum management”. In this paper, we examine the key issue to show how to conserve the energy of base stations in the Green CRNs. In order to meet the demand for more sustainable green communication, we propose a multiple-sleep mode for licensed channels in CRNs. Based on a dynamic spectrum access strategy with the proposed multiple-sleep mode, we establish a continuous-time Markov chain model to capture the stochastic behavior of secondary user (SU) and primary user packets. By using the matrix geometric solution method, we obtain the steady-state probability distribution for the system model. This paper further presents analysis for performance measures in terms of the throughput of SU packets, the average latency of SU packets, the energy saving rate of the system and the channel utilization. We also provide statistical experiments with analysis and simulation to investigate the influences of the service rate of one channel and the sleep timer parameter on the system performance measures. In order to get the utmost out of the spectrum resource and meet the demands for the quality of service requirements of SUs, we construct a system cost function, and improve a Jaya algorithm employing an insect-population model to optimize the proposed energy saving strategy. We also show the optimal combination and global minimum of the system cost by numerical results.

Study of relay-based ad hoc rendezvous and data transmission in cognitive radio networks

Cognitive radio (CR) access is an alternative way of providing mobile services while achieving effective spectrum utilization. CR users can transmit data to one another in a cognitive radio network (CRN) as long as the primary user is prevented from being affected. In addition, a CR user needs to rendezvous with its correspondent user in order to transmit data in an ad hoc manner. This study considers secondary users (SUs) that have the ability to access dual-interface for simultaneously for rendezvous and data transmission. A fully distributed dual-interface channel hopping for a rendezvous scheme is proposed as is the associated data delivery method for ad hoc communication in CR networks. The proposed rendezvous and data transmission schemes consider the channel contention of multiple SUs and the occurrence of primary users (PUs) when accessing radio. Furthermore, relay operations are applied in the proposed schemes to reduce the average time of rendezvous and data transmission. Simulation results indicate that the proposed relay-based schemes achieve shorter rendezvous time and higher throughput (because of the relay-based mechanism) and facilitate superior performance in both balanced and unbalanced peer-to-peer transmission environments.

Adaptive Full-Duplex Communications in Cognitive Radio Networks

In this paper, we propose a novel adaptive scheme for full-duplex communication of secondary users (SUs) in a cognitive radio network. The secondary network operates adaptively in three modes; cooperative sensing (CS), full duplex transmit and sensing (FDTS), and in-band bidirectional full duplex transmit and receive (FDTR). In the CS mode, the secondary nodes will detect the signal of a primary user (PU) through a novel cooperative medium access control (MAC) protocol and will decide the system's mode of operation in the subsequent spectrum hole. This adaptive decision is based on dual-threshold detection introduced for the first time. When the PU's signal at SU's receivers is weak, the system switches to the FDTS mode to avoid higher collisions probability and long or endless collision durations. In the FDTS mode, one of SUs senses the PU activity continuously while transmitting to another node. When the channel conditions allow, the system switches to the FDTR mode, in which the SUs would communicate bidirectionally in an asynchronous full duplex manner. The novel idea of asynchronous transmission in this mode will result in decreased maximum and average collision durations. Analytical closed forms for probability of collision, average collision duration, and cumulative collision duration, as well as throughput of the SU network are derived, and performance of the proposed scheme in terms of the above-mentioned metrics, effectiveness, and advantages over conventional methods of sensing and transmission are verified via simulations.

Secure multipath routing for multimedia communication in cognitive radio networks

In this paper, a novel technique for secure multihop communication in cognitive radio networks is proposed which allows the use of non-contiguous channels for communication of multimedia data without compromising the desired QoS. This technique first creates a number of sub-packets formed by suitably shuffling the bits of the original packet, finds multiple routes by executing the max-flow algorithm on a derivative of the network graph to meet the required bandwidth, suitably allocates channels for each hop in the multiple paths using the features of cognitive radio networks, and sends the sub-packets along these channels which are received by the destination node to form the original packet. This strategy also leads to significantly enhanced security of the data packets against the eavesdropping attack when multiple node-disjoint paths are chosen for transmitting the sub-packets.

Secure multipath routing for multimedia communication in cognitive radio networks

In this paper, a novel technique for secure multihop communication in cognitive radio networks is proposed which allows the use of non-contiguous channels for communication of multimedia data without compromising the desired QoS. This technique first creates a number of sub-packets formed by suitably shuffling the bits of the original packet, finds multiple routes by executing the max-flow algorithm on a derivative of the network graph to meet the required bandwidth, suitably allocates channels for each hop in the multiple paths using the features of cognitive radio networks, and sends the sub-packets along these channels which are received by the destination node to form the original packet. This strategy also leads to significantly enhanced security of the data packets against the eavesdropping attack when multiple node-disjoint paths are chosen for transmitting the sub-packets.