End-to-end performance of two-hop wireless communication systems with nonregenerative relays over flat Rayleigh-fading channels is presented. This accomplished by deriving and applying some new closed-form expressions for the statistics harmonic mean two independent exponential variates. It shown that presented results can either be exact or tight lower bounds on these depending choice relay gain. More specifically, average bit-error rate binary differential phase-shift keying, as well...

This letter presents a study on the end-to-end performance of dual-hop wireless communication systems equipped with nonregenerative fixed gain relays and operating over flat Rayleigh-fading channels. More specifically, it first derives generic closed-form expressions for outage probability average error when have arbitrary gains. It then proposes specific relay that benefits from knowledge hop's fading power compares its previously proposed gains in contrast require instantaneous channel...

Relayed transmission is a way to attain broader coverage by splitting the communication link from source destination into several shorter links/hops. One of main advantages this technique that it distributes use power throughout hops. This implies longer battery life and lower interference introduced rest network. In context, paper investigates optimal allocation over these links/hops for given budget. All hops are assumed be subject independent Rayleigh fading. Outage probability which...

We present a general analytical framework for the evaluation of end-to-end outage probability multihop wireless communication systems with nonregenerative relays over Nakagami fading channels. It is shown that presented results can either be exact or tight lower bounds on performance these depending choice relay gain. More specifically, we obtain closed-form expression moment generating function reciprocal signal-to-noise ratio (SNR) and then use this to calculate via numerical inversion...

Closed-form expressions for the statistics of harmonic mean two independent and identically distributed gamma variates are presented. The probability density function F is also derived. These statistical results then applied to study performance wireless communication systems with nonregenerative relays over flat Nakagami fading channels. More specifically, outage formulas noise-limited as well affected by interference obtained. Furthermore, general average bit-error rates Finally,...

In this paper, to further improve the coverage and performance of unmanned aerial vehicle (UAV) communication systems, we propose a reconfigurable intelligent surface (RIS)-assisted UAV scheme where an RIS installed on building is used reflect signals transmitted from ground source UAV, deployed as relay forward decoded destination. To model statistical distribution RIS-assisted ground-to-air (G2A) links, develop tight approximation for probability density function (PDF) instantaneous...

In this work, we study the secrecy performance of a reconfigurable intelligent surfaces (RIS)-aided wireless communication system in presence an eavesdropping user. Specifically, assume that RIS is placed between source and legitimate user used to improve link security. particular, analytical results for outage probability (SOP) are derived. We also provide asymptotic analysis investigate effect main parameters on our proposed system, such as number tunable elements average signal-to-noise...

Recent studies have shown that reconfigurable intelligent surfaces (RISs) can help in extending the wireless coverage. However, no work has quantitatively analyzed In this letter, we present coverage analysis for an RIS-aided communication system. For comparison, relaying systems and direct-link transmission are also derived. Furthermore, provide probability of signal-to-noise ratio (SNR) gain RIS over direct link transmission. Finally, analyze delay outage rate achieving ultra-reliable...

Closed form expressions for the statistics of harmonic mean two independent exponential variates are presented. These statistical results then applied to study performance wireless communication systems with non-regenerative relays over flat Rayleigh fading channels. It is shown that these can either be exact or tight lower bounds on depending choice relay gain. More specifically, outage probability formulas noise limited obtained. Furthermore, capacity and bit error rate (BER) binary...

Future mobile networks are converging toward heterogeneous multitier networks, where macro-, pico-, and femtocells randomly deployed based on user demand. A popular approach for analyzing (HetNets) is to use stochastic geometry treat the location of BSs as points distributed according a homogeneous Poisson point process (PPP). However, PPP model does not provide an accurate interference when nodes clustered around highly populated areas. This motivates us find better ways characterize...

With the emergence of Internet Things (IoT) technology, wireless connectivity should be more ubiquitous than ever. In fact, availability connection everywhere comes with security threats that, unfortunately, cannot handled by conventional cryptographic solutions alone, especially in heterogeneous and decentralized future networks. general, physical layer (PLS) helps bridging this gap taking advantage fading propagation channel. Moreover, adoption reconfigurable intelligent surfaces (RIS)...

In this paper, we consider a free-space optical (FSO) communication scheme with the help of variable gain relay where links from source to are radio-frequency (RF) while between and destination FSO M-distribution. To mitigate effects multipath fading atmospheric turbulence, apply transmit diversity at selection combining (SC) destination, is only equipped single RF receive antenna for receiving signal one aperture relaying information. With setup, first derive expressions outage probability,...

In this letter, we propose an UAV-based relaying system with energy harvesting functionality. particular, assume that is operated in urban communication environments, where the channel between UAV and land destination modeled as shadowed-Rician fading or shadowed-Rayleigh fading. Based on setting, outage probability analysis for different environment parameters derived. Finally, Monte Carlo simulations are conducted to verify accuracy of our analytical results.

This paper focuses on providing an analytical framework for the quantification and evaluation of pointing error at high-frequency millimeter wave (mmWave) terahertz (THz) communication links. For this aim, we first characterize channel a point-to-point link between to unstable transmitter (Tx) receiver (Rx) then, derive probability density function (PDF) cumulative distribution functions (CDF) in presence Tx Rx as antennas' pattern. Specifically, standard array antenna, closed-form...

In this work, we investigate a novel covert communication system, where the legitimate transmitter attempts to communicate with user in presence of warden and public covertly. Specifically, employs non-orthogonal multiple access (NOMA) rate-splitting (RS) users aided by reconfigurable intelligent surface (RIS). context, key performance indicators communication, namely detection error probability rate. Meanwhile, consider physical layer security (PLS) proposed system an eavesdropper, derive...

In the pursuit of ubiquitous broadband connectivity, there has been a significant shift towards vertical expansion communication networks into space, particularly through exploitation low Earth orbit (LEO) satellite constellations, which are favored for their relatively latency. However, this approach faces many challenges that need to be addressed, including atmospheric turbulence, high path loss, and dynamic cloud formations. High-altitude pseudo-satellites (HAPS) have emerged as promising...

Device-to-device (D2D) communications are now considered an integral part of future 5G networks, which will enable direct communication between user equipments and achieve higher throughputs than conventional cellular but with the increased potential for co-channel interference. The physical channels, constitute D2D communications, can be expected to complex in nature, experiencing both line-ofsight (LOS) non-LOS conditions across closely located pairs. In addition this, given diverse range...

A mixed free-space optical (FSO) communication scheme is considered with the help of a fixed gain relay. We assume that links from source to relay are radio frequency multiuser diversity operating in η-μ fading channels, while link between and destination FSO M-distribution. first derive expressions for cumulative distribution function end-to-end signal-tonoise ratio system pointing errors, then use them some exact closed-form outage probability, bit-error rate performance, ergodic capacity....

In this paper, we consider an amplify-and-forward hybrid satellite-terrestrial co-operative network in the presence of cochannel interference (CCI). More specifically, assume that both satellite-destination and satellite-relay links undergo shadowed-Rician fading relay-destination link follows Nakagami-m fading. By applying (AF) protocol at terrestrial relay, relay destination are corrupted by from network. Based on setup, first derive approximate statistical distributions...

Among the challenges of realizing full potential light-fidelity (LiFi) cellular networks are user mobility, random device orientation, and blockage. In this paper, we study impact those on performance LiFi in an indoor environment using measurement-based channel models, unlike existing studies that rely theoretical models. our adopt spatial modulation (SM) consider two configurations for equipment (TIE). A multidirectional receiver (MDR) structure is proposed, which PDs located different...

Unmanned aerial vehicles (UAVs) have recently been envisaged as an enabling technology of 5G. UAVs act intermediate relay node to facilitate uninterrupted, high quality communication between information sources and their destination. However, UAV energy management has a major issue consideration due limited power supply, affecting flight duration. Thus, we introduce in this paper unified framework by resorting wireless transfer (WPT), simultaneous (SWIPT) self-interference (SI) harvesting...

In this correspondence paper, we consider the performance of a mixed free-space optical and radio frequency (FSO-RF) relaying system with energy harvesting in existence both atmospheric turbulence pointing errors. More specially, assume that direct current component FSO signal, which is generally filtered out, can be used for at relay. We derive exact closed-form expression outage probability setup terms bivariate Fox-H function. also provide asymptotic analysis to obtain diversity order....

In this paper, we study the performance of a cooperative underwater acoustic communication/free-space optical communication (UAC-FSO) transmission system supported by fixed-gain amplify-and-forward (AF) relay, where an source transmits signals to satellite through help buoy functioning as relay located on sea surface. particular, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">K</i> and κ - μ shadowed fading distribution models are used...

In this paper, we study an unmanned aerial vehicle (UAV)-assisted relaying communication system, where a ground base station (GBS) intends to send information legitimate user (Bob) with the help of UAV relay, in presence passive eavesdropper (Eve). particular, assuming urban operating environment, analyze and derive closed-form approximation intercept probability ergodic secrecy rate. Through analytical numerical results, examine effect different system parameters on performance.

Weight reduction and low power consumption are key requirements in the next generation of unmanned aerial vehicle (UAV) networks. Employing modulating retro-reflector (MRR)-based free space optical (FSO) technology is an innovative technique for UAV-to-ground communication order to reduce payload weight UAVs which leads increased maneuverability flight time UAV. In this paper, we consider MRR-based FSO system communication. We will show that performance considered very sensitive tracking...