This paper proposes two novel and practical designs of angle diversity receivers to achieve multiple-input-multiple-output (MIMO) capacity for indoor visible light communications (VLC). Both are easy construct suitable small mobile devices. By using emitting diodes both illumination data transmission, our receiver consist multiple photodetectors (PDs), which oriented with different inclination angles high-rank MIMO channels can be closely packed without the requirement spatial separation....

A two-hop neighborhood information-based routing protocol is proposed for real-time wireless sensor networks. The approach of mapping packet deadline to a velocity adopted as that in SPEED; however, our decision made based on the novel integrated with energy balancing mechanism. Initiative drop control embedded enhance utilization efficiency, while reducing miss ratio. Simulation and comparison show new has led lower ratio higher efficiency than two existing popular schemes. result also...

This paper investigates the joint subcarrier and power allocation problem for downlink of a multi-carrier non-orthogonal multiple access (MC-NOMA) system. A novel three-step resource framework is designed to deal with sum rate maximization problem. In Step 1, we relax by assuming that each users can use all subcarriers simultaneously. With this assumption, prove convexity resultant control solve it via convex programming tools get vector user. 2, allocate heuristic greedy manner obtained...

Modern information and communication systems have become increasingly challenging to manage. The ubiquitous system logs contain plentiful are thus widely exploited as an alternative source for management. As log files usually encompass large amounts of raw data, manually analyzing them is laborious error-prone. Consequently, many research endeavors been devoted automatic analysis. However, these works typically expect structured input struggle with the heterogeneous nature logs. Log parsing...

Future wireless communication systems have been imposed high requirement on power efficiency for operator's profitability as well to alleviate information and technology (ICT) global carbon emission. To meet these challenges, the consumption minimization problem a generic multi-cell multiple input single output non-orthogonal access (MISO-NOMA) system is studied in this work. The associated joint user grouping, beamforming (BF) control mixed integer non-convex programming problem, which...

Non-orthogonal multiple access (NOMA) is a promising technology to increase the spectral efficiency and enable massive connectivity in 5G future wireless networks. In contrast orthogonal schemes, such as OFDMA, NOMA multiplexes several users on same frequency time resource. Joint subcarrier power allocation problems (JSPA) are NP-hard solve general. this family of problems, we consider weighted sum-rate (WSR) objective function it can achieve various tradeoffs between performance user...

We propose and analyze a class of distributed algorithms performing the joint optimization radio resources in heterogeneous cellular networks made juxtaposition macro small cells. show that within this context, it is essential to use able simultaneously solve problems channel selection, user association power control. In such networks, unpredictability cell patterns also requires self-optimized schemes. The proposed solution inspired from statistical physics based on Gibbs sampler. It can be...

Small cell network is designed to provide mobile services hot spots by deploying a large number of small access points (APs). As traditional deployment requires costly AP location acquisition, cost-effective necessary for networks. We investigate this question studying the performance in terms spatial outage and throughput completely random topology comparison that perfectly regular topology. Using stochastic geometry model user SINR topology, our results show gap guarantee becomes narrow...

As the demand for higher data rates is growing exponentially, homogeneous cellular networks have been facing limitations when handling traffic. These are related to available spectrum and capacity of network. Heterogeneous (HetNets), composed macro cells (MCs) small (SCs), seen as key solution improve spectral efficiency per unit area eliminate coverage holes. Due large imbalance in transmit power between MCs SCs HetNets, intelligent user association (UA) required perform load balancing...

Non-orthogonal multiple access (NOMA) is a promising radio technology for 5G. It allows several users to transmit on the same frequency and time resource by performing power-domain multiplexing. At receiver side, successive interference cancellation (SIC) applied mitigate among multiplexed signals. In this way, NOMA can outperform orthogonal schemes used in conventional cellular networks terms of spectral efficiency more simultaneous users. This paper investigates computational complexity...

The authors consider collision channel without feedback in which collided packets are considered unrecoverable. For each user, the transmission of follows a specific periodical pattern, called protocol sequence. Due to lack feedback, beginning sequences cannot be synchronized and nonzero relative offsets inevitable. It results variation throughput. In this paper, we investigate optimal sequence sets, sense that throughput variance is zero. Such said shift-invariant (SI). characterizing...

With the promising technology of far-field wireless power transfer, wearable devices are able to harvest radio frequency (RF) energy from RF-based chargers and thus operate continuously. Rational planning quantity positions provide an effective way improve recharging efficiency save charger deployment budget. Existing work on placement mainly considers situation where static, or adopt very simple mobility model. In this paper, we consider charging service provision for worn by users in a...

Traffic congestion in metropolitan areas presents a formidable challenge with far-reaching economic, environmental, and societal ramifications. Therefore, effective management is imperative, traffic signal control (TSC) systems being pivotal this endeavor. Conventional TSC systems, designed upon rule-based algorithms or reinforcement learning (RL), frequently exhibit deficiencies managing the complexities variabilities of urban flows, constrained by their limited capacity for adaptation to...

There is a growing demand for indoor positioning systems (IPS) in wide range of applications. However, traditional solutions such as GPS face many technical challenges. In recent years, promising alternative has been emerging: IPS based on visible light communication (VLC), which offers combination highly accurate, low cost and energy efficient. This article presents comprehensive review VLC-based IPS, providing tutorial-like overview the system. It begins by comparing various background...

We consider the problem of LTE network self organization and optimization resource allocation. One particular challenge for systems is that, by applying OFDMA, a transmission may use multiple blocks scheduled over frequency time. There are three key components involved in allocation optimization: block scheduling, power control, client association. propose distributed protocol that aims to achieve weighted proportional fairness (WPF) among clients jointly them. The cross-layer design...

ABSTRACT We study the weighted sum rate maximisation problem of wireless networks consisting multiple source–destination pairs. The optimisation is to maximise a data rates by adjusting power each user. in general non‐convex that will lead local maxima. A Gauss–Seidel type iterative control algorithm presented. proposed has favourable properties only simple operations are needed iteration and convergence fast. Performance investigation under some benchmark examples different user densities...

Conflict-avoiding codes are used in the multiple-access collision channel without feedback. The number of codewords a conflict-avoiding code is potential users that can be supported system. In this paper, new upper bound on size proved. This general sense it applicable to all lengths and Hamming weights. Several existing constructions for codes, which known optimal weights equal four five, shown general.

In indoor visible light communication systems, transmitters are usually within the line of sight receiver. order to enjoy benefits using multiple-input-multiple-output (MIMO) system, technique for reducing channel correlation is important. This paper proposes a MIMO system an angle diversity receiver (ADR) achieve high spatial multiplexing gain. our proposed consists multiple photodetectors (PDs) whose normals pointing toward different directions. As result, incident angles from same...

To obtain good network performance in Long Term Evolution-Advanced (LTE-A) heterogeneous networks (HetNets), enhanced inter-cell interference coordination (eICIC) and further eICIC (FeICIC) have been proposed by LTE standardization bodies to address the entangled user association problems. We propose distributed algorithms based on exact potential game framework for both FeICIC optimizations. demonstrate via simulations a 64% gain energy efficiency (EE) achieved another 17% EE FeICIC. also...

Non-orthogonal multiple access (NOMA) has received significant attention for future wireless networks. NOMA outperforms orthogonal schemes, such as OFDMA, in terms of spectral efficiency and massive connectivity. The joint subcarrier power allocation problem is NP-hard to solve general, due complex impacts signal superposition on each user's achievable data rates, well combinatorial constraints the number multiplexed users per sub-carrier mitigate error propagation. In this family problems,...

In this paper, we study non-orthogonal multiple access (NOMA) user scheduling and resource allocation problem for a generic downlink single-cell input single output (MISO) millimeter wave (mmWave) system. The larger number of packed antennas the highly directional property mmWave communications enable beamforming to achieve spatial diversity. Toward end, consider two different hybrid precoding schemes which are based on orthogonal matching pursuit (OMP). Users assigned into clusters base...

We explore the asymptotic performance of existing geographic routing with a utilization k-hop neighborhood information. The reachability from source to sink improves as we integrate more information into decision. It is observed that average number hops required decreases significantly 1-hop 2-hop based searching. This indicates an attractive tradeoff between enhancement and system complexity. As simple greedy forwarding insufficient in lossy wireless environment, propose new metric...

Protocol sequences are used for channel access in the collision without feedback. Each user is assigned a deterministic zero-one pattern, called protocol sequence. The zeros and ones sequence read out periodically, packet sent if only it one. A occurs two or more users transmit at same time. Due to lack of feedback from receiver cooperation among users, beginning cannot be synchronized relative delay offsets incurred. We study design different perspectives. Under first one, shift invariance,...