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This letter presents a compact slotted pentaband inset-fed microstrip antenna designed to operate for UMTS, WLAN, WiMAX, C-band and X-band applications. By incorporating equispaced slots of same width and length and also the inset feeding, the antenna generates five bands, allowing for penta-band operation. The antenna is manufactured on an FR4 substrate and is excited by an SMA connector using a microstrip line. With its compact dimensions of 25x25x1.6 mm3, the antenna offers a simple structure. Based on the simulated and measured outcomes, the proposed antenna demonstrates numerous advantages, making it highly suitable for wireless communication systems. These advantages include its ability to operate in multiple bands, its percentage bandwidth, compact size, stable radiation pattern, ease of processing, and costeffectiveness. [ABSTRACT FROM AUTHOR]

Currently in Ukraine, taking into account the development of the latest mobile Internet standards (3G/4G), it is possible to access the Internet even in remote places. There are no wired Internet due to the high cost of installation and maintenance. At the same time, a huge amount of equipment appeared on the market, which allows you to assemble systems for obtaining high-quality Internet over a wireless communication line. This refers to various types of antennas in the 900–2700MHz range, modems and routers with 3G/4G support. The locations of 3G/4G Internet base stations are in district centers predominantly. So, there is a situation that remote villages, settlements do not have the opportunity to get access to high-speed Internet. This especially harms the work of biological stations and rural medical clinics, which are spread over the territory of Ukraine and are often connected in a network. The purpose of the work is to describe briefly some practical results of our own development of providing high-quality mobile communication in some remote places of the territory of the state. To provide this service in remote areas of Ukraine, signal amplification is necessary. In addition, there is a problem with the propagation of radio waves over the rough terrains for the ultra short wave and microwave ranges. To solve this problem, it is proposed to use an external antenna with a high amplification factor, which will be installed at a height of at least 6 meters above the ground to reduce the impact of interference on the path of radio waves. [ABSTRACT FROM AUTHOR]

A stable and nationwide mobile network coverage is increasingly regarded as essential. This requires an expansion of mobile networks throughout the country. However, the installation of masts and antennas has often been the subject of con- flict in Germany, especially due to fears about potential health effects of electromagnetic fields. Transmitters become both a trigger and a target of social protests. From a discourse-theoretical perspective, we identify central lines of argumentation in the German cellular network conflicts. A triangulation of quantitatively oriented and qualitative analysis components forms the methodological basis. Regional case studies provide an opportunity to identify local differences. A comparison of past and recent conflicts reveals discursive shifts over time. Debates about the possible health effects of mobile radio were particularly contentious in the context of UMTSmobile phone expansion at the turn of the millennium. The (planned) installation of transmitters at the local level often sparked this discussion. During the expansion of the 5G network, in addition to the debate about the health risks of the technology, questions are now being raised about whether and to whom the expansion is necessary. Compared to the previous period of investigation, local conflicts about transmitters now appear to be less virulent and can be found primarily in southern and southwestern Germany. [ABSTRACT FROM AUTHOR]

The article presents the application of a new analytical model of the full-availability group carrying a mixture of different multi-rate traffic classes with compression property for modeling the WCDMA radio interface with packet scheduling. The proposed model can be directly used for modeling of theWCDMA interface in the UMTS network servicing different traffic classes. The described model can be applied for a validation of the efficiency of the WCDMA interface measured by the blocking probability and the average carried traffic for particular traffic classes.

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In this paper, a new antenna system for rapidly emerging multifunction devices is presented. The proposed antenna system consists of four antenna components each one operating at different frequency bands separately. The designed antennas are isolated and integrated on a single substrate. The first antenna is designed to operate at 1920-2170 MHz covering the UMTS band, whereas the second antenna is proposed for the lower band 5G systems and WiMAX operating within the frequency range of 3.4-4.2 GHz. Furthermore, another antenna is designed to cover the higher band 5G system and the IEEE 820.11a WLAN within the frequency range of 5.1-5.85 GHz. Finally, a 28 GHz bowtie-based MIMO antenna array is designed and simulated for the mmWave future 5G mobile networks. The proposed antennas were designed and simulated by using CST microwave studio. The results showed that all of the proposed antennas exhibited excellent reflection characteristics below -20 dB at the resonant frequency and achieved high radiation efficiency reached 99% in some cases with a peak gain ranging between 4-6 dBi. The proposed antenna system helps smartphones to perform multitasks and achieve a better-quality operation especially with the enormous growth of IoT techniques. [ABSTRACT FROM AUTHOR]

Recently, data traffic movement through a wireless channel is assisted by suggesting and implementing many mechanisms, to achieve the speedy increasing importunity and popularity of the wireless networks. Various wireless technologies can be copulated to develop a heterogeneous network, which is a candidate towards (4G) networks. OPNET modeler (14.5) is used to design simulation modules of the heterogeneous network. During device connection between the worldwide interoperability for microwave access (WiMAX) and universal mobile telecommunication system (UMTS) networks, Performance metrics such as; Jitter end-to-end delay (E-2-E) Throughput is used. The results of the simulation are measured to determine the efficiency of the transfer using WiMAX-UMTS according to the selected metrics. The WiMAX-UMTS has shown valuable improvement in Process Durability, reduction of E-2-E delay, and Jitter. The maximum amount of data transfer and the least amount of delay and Jitter is at 250 sec. Because of the handover operations and data transfer momentum, the worst-case passes in the network when 618 sec is the minimum amount. The efficiency of throughput for WiMAX equal to 0.092666% as for the efficiency of throughput for UMTS equal to 4.633333*10-6 % whereas the E-2-E efficiency a delay equal to 0.5466%. [ABSTRACT FROM AUTHOR]

Summary: In this present contemporary epoch, wireless communication appliances exemplified meteoric progression in technology. These systems entail an antenna in every strand of communication. Depending upon the recent expansions in generations, the antennas become more compact, lightweight, portable, wearable, cost‐effective, and conformal while maintaining essential performance characteristics like impedance bandwidth, efficiency, gain, SAR, etc. This review is envisioned to unveil state‐of‐art in conventional and unconventional antenna technologies in recent times and offers knowledge to readers about a large regime of antenna designs suitable for different wireless communication system applications like GSM, GPS, Wi‐Fi, WLAN, bluetooth, 4G, and 5G under a single head. It is unambiguously worth stating that recent 5G antenna designs will unleash new breaks in leapfrogging all outmoded blockades in developments. Intended wireless communication systems take in mobiles, laptops, smart wears, tablets, etc., while antenna technologies cover wearable models, conformal structures, MIMO configurations, microstrip and planar monopole antennas. This study draws attention towards multi‐band and wide‐band accomplishment techniques, SAR analysis, bending and twisting effects of conformal or wearable antennas, effect of human body and wireless appliances on antenna performance. As per the study, FCC set a standard value of SAR as equal or below to 1.6 W/kg for 1 g of body tissue. IEC standards regulated a limit on SAR value as 2 W/kg, which is average value over 10 g of body tissue. Also, envelope correlation coefficient (ECC) of below 0.05, diversity gain of less than 10 dB and a maximum channel capacity of 0.4 bit/s/Hz are necessary for MIMO systems. [ABSTRACT FROM AUTHOR]

Many researchers have discussed various topics in universal mobile telecommunication system (UMTS) networks: the process of switching from one cell to another for the subscriber and the impact of the quality of the connection during the transition process, quality of services (QoS), the quality of the uplink and downlink carrier line, the various types of code for the voice transmitted through the Internet, especially the research that discussed voice over internet protocol (VoIP) technology as voice travels from cell to cell in mobile networks, depending on the type of delivery. In this paper, a proposed scenario of a UMTS network was implemented to evaluate the multicellular VoIP movement; the proposed UMTS network was simulated using the OPNET 14.5 simulator. The calculation and analysis of the different parameters of the user while moving from one cell to another with different movement speeds considered, the best mean opinion score (MOS) value (3.19) registered for the scenario (soft handover) comparing with another type of handover (3.00). [ABSTRACT FROM AUTHOR]

The document presents the planning and simulation of UMTS and LTE mobile telecommunications network by the use of Small Cells technology in heterogeneous environments solutions for real foray operators in Cochabamba to achieve efficiency in resource usage in a state of high traffic load of voice and data, and therefore achieve better utilities. The methodology is based on analytical development, planning, and simulation which take place in the first instance with the collection of information. In the following steps, the project requirements were identified, a vendor technical specifications comparison was made, and the Small Cell networks were designed by radio access network planning, cell distribution and dimensioning, transportation cadasters definition, technical equipment parametrization, and frequency plan determination. Finally a procedure of simulation for coverage predictions and design validation was made. It is concluded that the project is feasible and complies with technical requirements for land survey, services demand on voice and data, coverage for indoor or outdoor environments, mobility and transport users, parameters performance on RSCP, RSRP, RSRQ signal-to-noise ratio, capacity of users, specific scenario solutions and economic benefits on deployments.

This paper describes an innovative approach to radio channel characterization in UMTS and LTE mobile networks. In place of traditional drive tests (DT), which employ a single test mobile, a massive collection of georeferenced radio measurements is made from a wide population of user equipment (UE). This is possible with new 3GPP features, called “minimization of DTs” (MDT), which are implemented in the last generation UEs and enable the reporting of additional periodical measurements, including GPS position and estimated UE distance (i.e. delay) over the radio path. This opens to new fields of investigation in the mobile radio channel, unreachable with the legacy DT approach, such as multipath and Doppler analysis. The UE MDT data of UMTS and LTE RAN of Telecom Italia Mobile, in the Italian midsized city of Bologna, have been statistically analyzed. The big data elaboration has been performed with the Nokia proprietary system “GeoSynthesis.” The results give a high-resolution geographical view of the above-mentioned channel phenomena affecting the quality and user experience. They are in good accordance with network performance indicators: the higher the multipath time, the worse the decoding performance of radio blocks (block error rate). The estimated Doppler shift also fits the known mobility patterns in the urban environment.

Beyond 5G networks will be fundamental towards enabling sustainable mobile communication networks. One of the most challenging scenarios will be met in ultra-dense networks that are deployed in densely populated areas. In this particular case, mobile network operators should benefit from new assessment metrics and data science tools to ensure an effective management of their networks. In fact, incorporating architectures allowing a cognitive network management framework could simplify processes and enhance the network's performance. In this paper, we propose the use of composite indicators based on key performance indicators both as a tool for a cognitive management of mobile communications networks, as well as a metric which could successfully integrate more advanced user-centric measurements. Composite indicators can successfully synthesize and integrate large amounts of data, incorporating in a single index different metrics selected as triggers for autonomous decisions. The paper motivates and describes the use of this methodology, which is applied successfully in other areas with the aim of ranking metrics to simplify complex realities. A use case that is based on a universal mobile telecommunications system network is analyzed, due to technology simplicity and scalability, as well as the availability of key performance indicators. The use case focuses on analyzing the fairness of a network over different coverage areas as a fundamental metric in the operation and management of the networks. To this end, several ranking and visualization strategies are presented, providing examples of how to extract insights from the proposed composite indicator. [ABSTRACT FROM AUTHOR]

In this study, the authors present results of a call testing campaign using voice over long term evolution (VoLTE) technology on the radio access network of the operator Telecom Italia mobile. The quality of the voice call is expressed by means of the mean opinion score (MOS). The electromagnetic propagation environment has been reproduced within a reverberation chamber, and its effect on MOS has been evaluated by varying the signal strength, i.e. the reference signal received power and the signal‐to‐interference noise ratio. The aim is to find a correlation between the radio propagation environment and the perceived quality of the speech. Regardless of the networks technology, voice quality could be impacted by several factors: traffic load of LTE evolved Node B, quality of service, radio pathloss, mutual radio interference, multipath and so on. Interference and multipath are added to the useful signal in order to deteriorate the MOS, until the VoLTE calls dropped. Target of such work is to properly set the thresholds that trigger a handover of single radio voice call continuity to other radio access technologies (UMTS or GSM). Tests take also into account the adaptive multi‐rate CoDec selected by the network. [ABSTRACT FROM AUTHOR]

In this paper, we analyze the Observed Time Difference of Arrival (OTDOA) technique to simultaneously estimate the position of the different user equipments and the relative time difference between Node Bs in real UMTS networks. We concentrate on comparing two methods to solve the nonlinear system of equations, the well-known Gauss-Newton and the Levenberg-Marquardt algorithm. We show this latter method offers better results, providing faster convergence, higher accuracy and more robustness. Finally, a modification to the classical Levenberg-Marquardt algorithm is proposed in order to avoid divergences in that method. [ABSTRACT FROM AUTHOR]

Universal Mobile Telecommunications System (UMTS), is the third generation (3G) of mobile communication which is based on the wideband code division multiple access (W-CDMA) radio access to provide bandwidth and spectral efficiency. Interference in 3G system is significantly lower compared to the preceded generations. However, it does not mean 3G is free from the issues associated with interferences, such as low signal quality and call drop. The interference level in UMTS can be measured by using the well-known parameter Received Total Wideband Power (RTWP). This parameter is affected by many factors such as number of the users connected to the system, combining second generation (2G) and 3G frequencies within the same geographical area, geographical causes (difference of Altitude), and hardware impairment. In this paper we intensively study how these factors affect the uplink interference level (i.e. RTWP value) in 3G system used by a particular telecommunications company, Asiacell company, Iraq. The obtained data shows that call drop is the most serious issue raised due to high value of RTWP in 3G system. We demonstrate that system enhancement, in terms of lower RTWP level, are obtained by adding second carrier to the sites, separating 2G band from 3G band using special filter, and optimizing the hardware components. [ABSTRACT FROM AUTHOR]

Vehicular networking has gained considerable interest within the research community and industry. The automotive industry is supporting the notion of pervasive connectivity by agreeing to equip vehicles with devices required for vehicular ad hoc networking. Equipped with these devices, mobile nodes in vehicular ad hoc networks (VANETs) are capable of hosting many types of applications as services for other nodes in the network. This research focuses on addressing the challenges of location-dependence, intermittent network connectivity and irregular network traffic flows in unplanned areas for VANETs to host and operate non-safety-critical VANETs services. We assume unplanned areas as the one that lack communication infrastructure and planning. Such areas observe irregular vehicular traffic on the roads as well as on the networks. This research investigates the shortcomings of location-dependence, intermittent network connectivity and irregular network traffic flows and addresses them by exploiting location-dependent service migration over an integrated network in an efficient and cost-effective manner. [ABSTRACT FROM AUTHOR]

The dynamism associated with quality of service (QoS) requirement for traffic emanating from smarter end users devices founded on the internet of things (IoTs) drive, places a huge demand on modern telecommunication infrastructure. Most telecom networks, currently utilize robust call admission control (CAC) policies to ameliorate this challenge. However, the need for smarter CAC has becomes imperative owing to the sensitivity of traffic currently being supported. In this work, we developed a prioritized CAC algorithm for third Generation (3G) wireless cellular network. Based on the dynamic priority CAC (DP-CAC) model, we proposed an optimal dynamic priority CAC (ODP-CAC) scheme for Universal Mobile Telecommunication System (UMTS). We then carried out simulation under heavy traffic load while also exploiting renegotiation among different call traffic classes. Also, we introduced queuing techniques to enhance the new calls success probability while still maintaining a good handoff failure across the network. Results show that ODP-CAC provides an improved performance with regards to the probability of call drop for new calls, network load utilization and grade of service with average percentage value of 15.7%, 5.4% and 0.35% respectively. [ABSTRACT FROM AUTHOR]

Over the years the need for mobile broadband had seen a great increment due to the demand of internet mobile users. In this research work, data size for Internet operation on UMTS mobile network operators on the University of Ilorin Campus was assessed. The study assessed three UMTS network operators using an Infinix T627 android smart phone and RantCell App. to measure the download and upload at the selected points on the University of Ilorin Campus. It was observed that the number of active subscribers with their relative position in a cell have a great effect on the performance of the networks and therefore, the authors recommend the need for the operators to improve their data sizes so as to enhance users' satisfaction. [ABSTRACT FROM AUTHOR]