We address the fundamental tradeoffs among latency, reliability and throughput in a cellular network. The most important elements influencing KPIs 4G network are identified, inter-relationships them is discussed. use effective bandwidth capacity theory as analytical framework for calculating maximum achievable rate given latency constraint. analysis conducted simplified LTE network, providing baseline - yet powerful insight of main tradeoffs. Guidelines to extend more complex systems also...

This work analyzes the joint influence of channel fading and data outsourcing process in QoS metrics a wireless system. As first contribution, expressions effective bandwidth function (also known as capacity) for time-correlated Rayleigh under different adaptive rate policies are obtained. result allows us to analytically evaluate maximum constant information that can be transmitted over probabilistic delay constraint. Later, this Capacity with Probabilistic Delay Constraint C <sub...

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...

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...

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...

Visible light communication (VLC) is a promising ubiquitous design alternative for supporting high data rates. Its application has been primarily oriented to indoor scenarios, but the proliferation of light-emitting diodes in streets warrants its investigation outdoor scenarios as well. This paper studies feasibility VLC conventional scenario, when optical orthogonal frequency division multiplexing techniques are employed. The presence sunlight reduces system's performance, hence...

Presented here is an approach to analyzing the effect of imperfect channel estimation on adaptive modulation. The sensitivity main performance parameters short-term and long-term error sources summarized in a set new formulas that are either closed-form expressions or simple compute numerically.

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 paper, we present an analytical study of the bit error rate (BER) for single-carrier frequency-division multiple access (SC-FDMA) transmission over frequency-selective fading channels when zero-forcing frequency-domain equalization is applied. SC-FDMA, which can be described as a precoded version orthogonal (OFDMA), regarded promising candidate next mobile communication systems due its favorable envelope characteristics and low peak-to-average-power ratio (PAPR), compared with that...

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...

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...

Vehicle-to-vehicle (V2V) communications have seen growing attention in the last few years. In this work, we address use of 3GPP Long Term Evolution (LTE) standard technology applied to V2V. We employ empirical models for V2V channel, and show results from comprehensive computer simulations, based upon both uplink (UL) downlink (DL) standards LTE. provide 10 MHz 20 channels, terms BER, BLER, spectral efficiency throughput, using multiple MIMO modes. Results attractive feasibility LTE...

In this letter, the utilization of a finite number power levels per constellation in adaptive QAM schemes for flat fading channels is analyzed. Assuming maximum target BER, optimum switching thresholds order to maximize spectral efficiency are found Rayleigh fading. Both analysis and simulation results show that small allows obtain good compromise between high low feedback information rate.

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...

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,...

Single Carrier Frequency Division Multiple Access (SC-FDMA) is nowadays a promising technology for uplink transmission in 4G mobile communications systems. That mostly due to its favorable envelope characteristics, low PAPR and the fact performance similar that achieved with Orthogonal Domain (OFDMA). We present our analysis of BER SC-FDMA over Rayleigh fading channel ideal linear frequency-domain equalization. Expressions under assumption independence among allocated sub-carriers are...

The use of finite state Markov chains (FSMC) for the simulation Rayleigh channel has been generalized in last years. Several parameters influence construction chain. chain can be defined terms complex response, envelope received signal or Signal to Noise Ratio. Moreover partition method selected among various options. This paper presents an evaluation FSMC, including a novel that makes uniform division density function desired and comparison with other methods generation fading channel....