In this paper, we introduce a sophisticated path loss model incorporating both line-of-sight (LoS) and non-line-of-sight (NLoS) transmissions to study their impact on the performance of dense small cell networks (SCNs). Analytical results are obtained for coverage probability area spectral efficiency (ASE), assuming general special case with linear LoS function. The NLoS in SCNs terms ASE is significant, quantitatively qualitatively, compared previous work that does not differentiate...

With the formidable growth of various booming wireless communication services that require ever increasing data throughputs, conventional microwave band below 10 GHz, which is currently used by almost all mobile systems, going to reach its saturation point within just a few years. Therefore, attention radio system designers has been pushed toward higher segments frequency spectrum in quest for increased capacity. In this article we investigate feasibility, advantages, and challenges future...

IL-18 is a proinflammatory cytokine produced by macrophages and other cell types present in the kidney during ischemia-reperfusion injury (IRI), but its role this unknown. Here, compared with wild-type mice, IL-18(-/-) mice subjected to IRI demonstrated better function, less tubular damage, reduced accumulation of neutrophils macrophages, decreased expression molecules that are downstream IL-18. For determination relative contributions leukocytes parenchymal cells production subsequent...

Various key-value (KV) stores are widely employed for data management to support Internet services as they offer higher efficiency, scalability, and availability than relational database systems. The log-structured merge tree (LSM-tree) based KV have attracted growing attention because can eliminate random writes maintain acceptable read performance. Recently, the price per unit capacity of NAND flash decreases, solid state disks (SSDs) been extensively adopted in enterprise-scale centers...

A novel dual-broadband planar antenna is proposed for 2G/3G/LTE (4G) mobile communications. The consists of one element the lower band and two elements upper band, making it possible to be arrayed without appearance grating lobes in band. lower-band comprises a pair printed dipoles with parasitic bandwidth enhancement. Two upper-band composed pairs folded are nested inside element, forming compact arrayable unit. achieves 20% (800-980 MHz) 60% (1540-2860 array that 4 8 developed base station...

A novel broadband planar antenna is developed for mobile communication base stations. The composed of a pair folded dipoles which are coupling fed by an L-shaped microstrip line. Both the and line etched on same substrate. achieves bandwidth 53% return loss} > 15 dBi covering frequency range 1.65-2.85 GHz 2G/3G/LTE applications. gain element about 9 dBi. 45° dual-polarized consisting two elements proposed, 50% isolation 30 dB. Two 8-element arrays respectively ${pm}45^{circ}$ antenna....

This paper is concerned with the channel estimation problem in millimeter wave (mmWave) wireless systems large antenna arrays. By exploiting inherent sparse nature of mmWave channel, we first propose a fast (FCE) algorithm based on novel overlapped beam pattern design, which can increase amount information carried by each measurement compared to existing nonoverlapped designs and thus reduce required time. We develop maximum likelihood estimator optimally extract path from measurements....

One of the fundamental problems in cryptography is generation a common secret key between two legitimate parties to prevent eavesdropping. In this paper, we propose an information-theoretic (SKG) method for time division duplexing (TDD)-based orthogonal frequency-division multiplexing (OFDM) systems over multipath fading channels. By exploring physical layer properties wireless medium, i.e., reciprocity, randomness, and privacy features radio channel, SKG proposed maximize number bits given...

In this paper, we introduce a sophisticated path loss model into the stochastic geometry analysis incorporating both line-of-sight (LoS) and non- (NLoS) transmissions to study their performance impact in small cell networks (SCNs). Analytical results are obtained on coverage probability area spectral efficiency (ASE) assuming general special case of recommended by 3rd Generation Partnership Project (3GPP) standards. The LoS NLoS SCNs terms ASE is shown be significant quantitatively...

In this letter, we focus on the efficient channel estimation problem for millimeter wave (MMW) systems with massive antenna arrays and RF constraints, aiming at achieving a fast high resolution angle-of-arrival/angle-of-departure (AoA/AoD) estimation. We first propose presentation of array virtual elements (AAVE) by appending additional into original array. On basis AAVE structure, explore sparsity in angular domain develop an angle algorithm using compressive sensing theories. then proposed...

This paper is concerned with the decentralized power allocation problem in random access systems. We propose a scheme that especially suitable for systems requiring high throughput but difficulty establishing centralized control, such as cognitive radio environments. Specifically, we assume successive interference cancellation (SIC) at receiver multi-packet reception (MPR). consider transmission strategy where each user selects its transmitted level randomly according to distribution...

A compact coplanar waveguide (CPW)‐fed triple‐band monopole antenna with high‐band isolation for various wireless applications is presented. The proposed composed of a CPW‐fed structure and hexagon‐shaped patch on which slot etched covering the local area network (WLAN) band (2.4/5.2/5.8 GHz), occupies very size 26 × 25 mm 2 . By introducing half‐hexagon‐shaped stub, additional bands can be realised worldwide interoperability microwave access (WIMAX) (2.5/3.5/5.5 GHz). has been fabricated...

Multipath transmission control protocol (MPTCP) has attracted significant attention from standardization bodies, industrial communities, and academic communities. However, an important performance-related aspect is that MPTCP negatively affected by packet reordering, especially in heterogeneous wireless environments. Although to improve the protocol, proposed updated scheduling policies congestion methods do not solve problem fundamentally. In this context, breaking strong binding between...

Terahertz (THz) transmission technologies constitute a promising candidate for supporting ultra-broadband short-range next generation communications. Hence, we analyse the performance of unmanned aerial vehicle (UAV) in THz networks. The coverage probability is derived as well area spectral efficiency (ASE) and pair Line-of-sight (LoS)/non-line-of-sight (NLoS) models, namely macrocell LoS/NLoS model picocell are adopted. Furthermore, lower-bound network via homogeneous Poisson point process...

Accurately reconstructing the intricate structure of natural organisms is long-standing goal 3-dimensional (3D) bioprinting. Projection-based 3D printing boasts highest resolution-to-manufacturing time ratio among all 3D-printing technologies, rendering it a highly promising technique in this field. However, achieving standardized, high-fidelity, and high-resolution composite structures using bioinks with diverse mechanical properties remains marked challenge. The root challenge lies neglect...

Collaborative beamforming (CB) has been widely used in a wireless sensor network (WSN) to improve the directivity of signals long-distance transmission. CB performance analyzed for some specific node distributions such as Uniform and Gaussian distributions. However, results obtained based on particular distribution WSN under condition may not be true other WSNs different conditions. This letter proposes novel unified method evaluate various The simulation verify proposed method.

This paper studies the fundamental characteristics of point-to-point E-band channels with uniform linear antenna arrays (ULAs) deployed at both transmitter and receiver. We model as line-of-sight (LoS) multiple-input multiple-output (MIMO) ones focus on channel eigenvalue characterization when <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Rayleigh distance criterion</i> cannot be fulfilled due to limited physical sizes first derive explicit...

This communication proposed an ultra-high frequency (UHF) stacked Hilbert antenna array to broaden bandwidth and increase gain of fractal antenna. Two parasitic curves were added improve the third order curve structure was applied new element. The UHF designed as that involved 2 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex Notation="TeX">$\times$</tex></formula> elements fed by Wilkinson's four-way power...

This paper is concerned with the capacity of multiple-input multiple-output (MIMO) cellular systems. We assume an equal rate constraint for all users and adopt a realistic channel model that incorporates path loss, lognormal fading Rayleigh fading. Several bounds are derived minimum transmission power such rate-constrained MIMO systems various base station (BS) cooperation strategies. In particular, upper bound based on maximum eigenmode beamforming (MEB) scheme. These then used to obtain...

ABSTRACT Cooperative communication has the potential of providing better throughput and reliability to wireless systems when compared with direct communication. To realise gain, it is important design cooperative strategies for some representative scenarios. This survey deals three basic relay channels, namely, parallel channel, multiple‐access channel broadcast channel. For first which models a single unicast connection, various forwarding are studied. second third model, respectively,...