The communication between two legitimate peers in the presence of an external eavesdropper is studied from a physical-layer security perspective context free-space optical (FSO) communications. We discuss viable mechanisms to eavesdrop and study effect random irradiance fluctuations inherent FSO communications on probability achieving secure transmission. observe that joint laser-beam divergence turbulence-induced fading received irradiance, under certain conditions, allows close receiver...

LTE V2X is the response of 3GPP standardization body to high market expectations related vehicular communications for safety and infotainment services. To fulfill stringent requirements in terms reliability associated with applications, geolocation-based access (GLOC) has been proposed direct vehicle-to-vehicle (V2V) communication. Such a scheme aims at maximizing distance co-channel transmitters (i.e., transmitter that use same resources) while preserving low latency when accessing...

Millimeter-wave communications have been recently proposed as a promising candidate to fulfill the connectivity requisites imposed over autonomous driving. The need for transmission capabilities of multiple gigabits per second vehicles is main driving factor millimeter-wave technology. However, there are other paramount requirements, such short delays, high reliability, security, and support both unicast broadcast communications, which must be carefully addressed before this technology...

We propose a novel architecture for providing quality of experience (QoE) awareness to mobile operator networks. In particular, we describe possible QoE-driven resource control long-term evolution (LTE) and LTE-advanced networks, including selection KPIs be monitored in different network elements. also provide description numerical results the QoE evaluation process data services as well potential use cases that would benefit from rollout proposed framework.

Link adaptation (LA) process is a core feature for the downlink of 3GPP long-term evolution (LTE) and LTE-advanced (LTE-A). Through channel quality indicator (CQI), receiver suggests to base station (BS) an appropriate modulation coding scheme (MCS) according current conditions. In order overcome any non-ideality in this process, outer loop link (OLLA) algorithm used adaptively modify mapping from signal-to-noise ratio (SNR) CQI. OLLA basically modifies measured SNR by offset, whether data...

Inter-cell interference is one of the main limiting factors in current Heterogeneous Cellular Networks (HCNs). Uplink Fractional Power Control (FPC) a well known method that aims to cope with such factor as save battery live. In order do that, path losses associated Mobile Terminal (MT) transmissions are partially compensated so lower leaked towards neighboring cells. Classical FPC techniques only consider set parameters depends on own MT transmission, like desired received power at Base...

Despite commercial 3G networks are starting to be fully operational and high speed data packet access (HSDPA) is on its way deployed, operators manufacturers already in a race towards 4G technologies. The road has mandatory milestone long term evolution (LTE) as it promising technology which will allow backwards compatibility besides higher performance. Thus operators, research institutes cooperating the definition of LTE specifications. This paper presents performance evaluation downlink...

The physical layer security of uplink non-orthogonal multiple access (NOMA) is analyzed. A stochastic geometry approach applied to analyze the coverage probability and effective secrecy throughput (EST) kth NOMA user, where a fixed or an adaptive transmission rate can be used. We consider protected zone around legitimate terminals establish eavesdropper-exclusion area. assume that channel state information associated with eavesdroppers not available at base station. also station equipped...

In this paper, we present an Android application which is able to evaluate and analyze the perceived quality of experience (QoE) for YouTube service in wireless terminals. To achieve goal, carries out measurements objective (QoS) parameters, are then mapped onto subjective QoE (in terms mean opinion score, MOS) by means a utility function. Our also informs user about potential causes that lead low MOS as well provides some hints improve it. After each session, users may optionally qualify...

In this letter, we obtain the optimal signal-to-noise ratio regions for adaptive modulation and coding (AMC) over a set of correlated subcarriers. We use logistic regression to model block error rate (BLER) with aim maximizing throughput while keeping BLER below predefined target. also study robustness suboptimal optimization procedure, which maintains relative distance among thresholds that preserving instantaneous under Moreover, bring new understanding outer loop link adaptation (OLLA)...

In this article, an end-to-end quality of service framework for streaming services in 3G mobile networks is considered. Under scenario, the interaction between UMTS and IETF's protocols mechanisms a session analyzed. By signaling flowcharts, it shown that both groups can co-operate to provide seamless real-time services. Specifically, article proposes make IP multimedia subsystem aware real time protocol, order extend its control from SIP RTSP-based services, such as Supported by proposed...

We show that the problem of analyzing outage probability in cellular systems affected by co-channel interference and background noise is mathematically equivalent to wireless information-theoretic security terms maximum secrecy rate fading channels. Hence, these both apparently unrelated problems can be addressed using a common approach. illustrate applicability connection unveiled herein provide new results for different scenarios.

In this paper, a novel non-orthogonal multiple access (NOMA)-enabled framework for cloud-radio networks (CRANs) is proposed. framework, two users are scheduled in the same resources according to NOMA; however performance of cell-edge enhanced by means coordinating beamforming. Stochastic geometry invoked modeling proposed where positions BSs follow cluster point process. an effort characterize simple expressions terms outage probability derived both nearby and users. It analytically...

The complexity of next generation wireless systems is growing exponentially. combination Multiple-Input Multiple-Output (MIMO) technology with Orthogonal Frequency Division Multiplexing (OFDM) considered as the best solution to provide high data rates under frequency-selective fading channels. design and evaluation MIMO-OFDM require a detailed analysis number functionalities such MIMO transmission modes, channel estimation, detection, coding, or cross-layer scheduling. In this paper we...

Global System for Mobile Communications Railways (GSM-R) has been the de facto standard wireless communications in field of High Speed Railway (HSR). However due to increasing requirements associated with HSR, Long Term Evolution (LTE-R) presented as following communication system. In this paper a complete performance analysis LTE HSR is carried out giving results both Physical (PHY) and Medium Access Control (MAC) layer order identify appropriate Quality Service (QoS) requirements. An...

Summary Evaluation of complex wireless systems through simulations is commonly tackled with an abstraction physical link behavior. This procedure performed in 2 phases: Firstly, training at the level, resulting a mapping function from signal‐to‐interference‐plus‐noise ratio (SINR) to block error rate (BLER); and secondly, layer signal processing replaced by link‐level function. Several methods have been proposed literature for abstraction. The well‐known exponential effective SINR (EESM)...

We analyze the coverage probability of multi-user uplink cellular networks with fractional power control. use a stochastic geometry approach where mobile users are distributed as Poisson Point Process (PPP), whereas serving base station (BS) is placed at origin. Using conditional thinning, we able to calculate $k$ which allocated set orthogonal resources in cell interest, obtaining analytical expressions for this considering their respective distances BS. These give useful insights on...

The seismic demands of bridges subjected to strong earthquakes are mostly concentrated on piers. main objective this study is assess the vulnerability retrofitted with steel jackets. It analyzes influence jacket thickness capacity and demand bridges. in have two simple supported spans superstructure composed by AASHTO type girders a substructure formed one circular pier over stiff foundation. They located Pacific coast Mexico that zone high seismicity. evaluated through nonlinear static...

In this work multiplexing of variable-rate sources over shared generic multiple fading channels is addressed. general, the performance existing algorithms has been compared in very specific environments, making it difficult to draw general conclusions. article we propose a multiuser and multichannel system model that can be applied any orthogonal channel mechanism (e.g., TDM, OFDM, CDM, or SDM) through parametric modeling. Based on model, different proposed literature evaluated moderately...

In this letter, we present two mechanisms based on soft-output Viterbi algorithm (SOVA) technique that achieve a performance close to maximum a-posteriori (MAP) decoding.First, propose new called alternating direction SOVA, which allows for improving the of SOVA in similar terms as bidirectional while barely affecting area complexity.Then, introduce idea parallel turbo decoding path metric/state border exchange.Unlike other techniques, overlapping between adjacent subblocks is not required,...

With the speeding up of fifth generation (5G) new radio (NR) worldwide commercialization, one paramount questions for operators and vendors is how to optimize links, considering widely diverse scenarios envisioned. One key pillars 5G has been an unprecedented flexibility on configuration access network (RAN) that include cellular, vehicular, industrial networks among others. This its main exponent link adaptation (LA), which evolved into a multi-domain technique where plethora parameters,...