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This paper presents a low-profile coplanar dual-polarized dual-band base station antenna array. A slotted patch antenna operating from 0.82 to 0.99 GHz with four shorting strips is proposed and analyzed. The four shorting strips are employed not only to improve the impedance matching in the lower band but also to remove the center part of the patch, thus making room for higher band dipoles operating from 1.68 to 2.86 GHz. The height of the proposed array is nearly half of the conventional base station array while other performances are guaranteed. The measured results show that the proposed antenna array has wide impedance bandwidths of 18.7% (0.82–0.99 GHz) and 57.9% (1.68–2.86 GHz) (VSWR < 2) with a low profile ($0.109\lambda _{0}$ at 820 MHz). The measured gains are 13.8±0.5 dB and 16.7 ± 1 dB in lower and upper bands. Large front-to-back ratio (>24.6 dB) and high isolations (>30 and >25 dB in lower and upper bands, respectively) are achieved. The proposed antenna can be easily built with printed circuit board fabrication technique and applied in low profile multiband base stations for 2G/3G/4G and the next-generation systems. [ABSTRACT FROM AUTHOR]

The bandwidth (BW) of a broadband dual-polarized antenna is enhanced for 2G/3G/4G systems and international mobile telecommunications services. The broadband dual-polarized element is a four-leaf clover antenna. By introducing a U-shaped slot to each leaf of the four-leaf clover and a parasitic element of four disks above the dual-polarized element, the BW enhancement is achieved. It is shown by simulation and experiment that the BW enhanced dual-polarized antenna achieves a BW of 67% (1.39–2.8 GHz) for reflection coefficients <−15 dB with an isolation (ISO) of 30 dB. An eight-element antenna array is developed for base station applications. The antenna array has a BW of about 70% (1.32–2.74 GHz) with an ISO of 25 dB. The antenna array achieves an average gain of ~17 dBi and a half-power beamwidth of 65 ± 5°, suitable for base station applications. [ABSTRACT FROM AUTHOR]

Well-deployed cellular networks offer a cheap wireless solution for the control channel deployment of Remote-Control Vehicles (RCV) and Unmanned Aerial Vehicles (UAV). However, a cellular data transfer service performance is affected by a different kind of User Equipment (UE) mobility. Operating conditions of UAV imply working at different altitudes, variable velocities with accelerations/decelerations and rapidly changed antennas angular position, which lead the wireless signal to be prone to negative effects. Available field measurement studies are not sufficient to provide excessive information on degradation problem causes for UEs moving along a complex trajectory. This paper presents an evaluation of the service quality of live operational 3G and LTE networks for both ground moving and flying UE. It has been found that antennas angular position variations in 3D (for example, during UAV manoeuvers) increase data transfer latency and jitter. Moreover, this effect in conjunction with higher interference at high altitudes may partially or fully block the data transfer service. This paper has been prepared to draw attention to the problem that makes the cellular data transfer service unusable for highly-manoeuvrable UAVs. [ABSTRACT FROM AUTHOR]

During the austral summer of 2016-2017, the third-generation camera, SPT-3G, was installed on the South Pole Telescope, increasing the detector count in the focal plane by an order of magnitude relative to the previous generation. Designed to map the polarization of the cosmic microwave background, SPT-3G contains ten 6′′-hexagonal modules of detectors, each with 269 trichroic and dual-polarization pixels, read out using 68× frequency-domain multiplexing. Here we discuss design, assembly, and layout of the modules, as well as early performance characterization of the first-year array, including yield and detector properties. [ABSTRACT FROM AUTHOR]

A new receiver for the South Pole Telescope, SPT-3G, was deployed in early 2017 to map the cosmic microwave background at 95, 150, and 220 GHz with ∼ 16,000 detectors, 10 times more than its predecessor SPTpol. The increase in detector count is made possible by lenslet-coupled trichroic polarization-sensitive pixels fabricated at Argonne National Laboratory, new 68× frequency-domain multiplexing readout electronics, and a higher-throughput optical design. The enhanced sensitivity of SPT-3G will enable a wide range of results including constraints on primordial B-mode polarization, measurements of gravitational lensing of the CMB, and a galaxy cluster survey. Here we present an overview of the instrument and its science objectives, highlighting its measured performance and plans for the upcoming 2018 observing season. [ABSTRACT FROM AUTHOR]

We have developed superconducting Ti transition-edge sensors with Au protection layers on the top and bottom for the South Pole Telescope’s third-generation receiver (a cosmic microwave background polarimeter, due to be upgraded this austral summer of 2017/2018). The base Au layer (deposited on a thin Ti glue layer) isolates the Ti from any substrate effects; the top Au layer protects the Ti from oxidation during processing and subsequent use of the sensors. We control the transition temperature and normal resistance of the sensors by varying the sensor width and the relative thicknesses of the Ti and Au layers. The transition temperature is roughly six times more sensitive to the thickness of the base Au layer than to that of the top Au layer. The normal resistance is inversely proportional to sensor width for any given film configuration. For widths greater than five micrometers, the critical temperature is independent of width. [ABSTRACT FROM AUTHOR]

The South Pole Telescope third-generation (SPT-3G) receiver was installed during the austral summer of 2016-2017. It is designed to measure the cosmic microwave background across three frequency bands centered at 95, 150, and 220 GHz. The SPT-3G receiver has ten focal plane modules, each with 269 pixels. Each pixel features a broadband sinuous antenna coupled to a niobium microstrip transmission line. In-line filters define the desired band-passes before the signal is coupled to six bolometers with Ti/Au/Ti/Au transition edge sensors (three bands × two polarizations). In total, the SPT-3G receiver is composed of  16,000 detectors, which are read out using a 68× frequency-domain multiplexing scheme. In this paper, we present the process employed in fabricating the detector arrays. [ABSTRACT FROM AUTHOR]

In this work, we have measured the properties of membrane-suspended bolometer thermal links and microstrip transmission lines in the transition-edge sensor arrays for the third-generation camera for South Pole Telescope (SPT-3G). A promising technique for controlling the end point of the release etch that defines the thermal link has been developed. We have also evaluated the microstrip loss in our detectors by measuring the optical efficiency of detectors with different lengths of microstrip line. The loss tangent is sufficiently low for the use in multi-chronic pixels for cosmic microwave background instruments like SPT-3G. [ABSTRACT FROM AUTHOR]

Nowadays, manufacturers want to send the data of their products to the cloud so that they can conduct analysis and improve their operation, maintenance, and services. Manufacturers are looking for a self-contained solution. This is because their products are deployed in a large number of different buildings, and it is neither feasible for a vendor to negotiate with each building to use the building's network (e.g., WiFi) nor practical to establish its own network infrastructure. The vendor can rent a dedicated channel from an ISP to act as a thing-to-cloud communication (TCC) link for each of its IoT devices. The readily available choices, e.g., 3G, is over costly for most IoT devices. ISPs are developing cheaper choices for TCC links, yet we expect that the number of choices for TCC links will be small as compared to hundreds or thousands of requirements on different costs and data rates from IoT applications. We address this issue by proposing a communication sharing architecture sTube+, sharing tube. The objective of sTube+ is to organize a greater number of IoT devices, with heterogeneous data communication and cost requirements, to efficiently share fewer choices of TCC links and transmit their data to the cloud. We take a design of centralized price optimization and distributed network control. More specifically, we architect a layered architecture for data delivery, develop algorithms to optimize the overall monetary cost, and prototype a fully functioning system of sTube+. We evaluate sTube+ by both experiments and simulations. In addition, we develop a case study on smart maintenance of chillers and pumps, using sTube+ as the underlying network architecture. [ABSTRACT FROM AUTHOR]

Accessing multiple carrier networks (T-Mobile, Sprint, AT&T, and so on) offers a promising paradigm for smartphones to boost its mobile network quality. However, the current practice does not achieve the full potential of this approach because it has not utilized fine-grained, cellular-specific domain knowledge. Our experiments and code analysis discover three implementation-independent issues: 1) it may not trigger the anticipated switch when the serving carrier network is poor; 2) the switch takes a much longer time than needed; and 3) the device fails to choose the high-quality network (e.g., selecting 3G rather than 4G). To address them, we propose iCellular, which exploits low-level cellular information at the device to improve multi-carrier access. iCellular is proactive and adaptive in its multi-carrier selection by leveraging existing end-device mechanisms and standards-complaint procedures. It performs adaptive monitoring to ensure responsive selection and minimal service disruption and enhances carrier selection with online learning and runtime decision fault prevention. It is readily deployable on smartphones without infrastructure/hardware modifications. We implement iCellular on commodity phones and harness the efforts of Project Fi to assess multi-carrier access over two U.S. carriers: T-Mobile and Sprint. Our evaluation shows that, iCellular boosts the devices’ throughput with up to $3.74\times $ throughput improvement, $6.9\times $ suspension reduction, and $1.9\times $ latency decrement over the state of the art, with moderate CPU, and memory and energy overheads. [ABSTRACT FROM AUTHOR]

A novel magneto-electric dipole antenna with wide H-plane beamwidth, triple-linear polarisation and frequency reconfiguration is proposed for 5G communications. In this study, the radiated dipoles are designed with the arc-shaped planes to exhibit wide H-plane performance. A bent cross-dipole feed with PIN diodes and varactor diodes inserted into its four arms at different altitudes is utilised to excite and control the antenna. Consequently, a measured wide beamwidth ranging from -67° to 67° can be achieved in H-plane. In addition, the height of the proposed antenna decreased about 30% due to the bent designs. Finally, by controlling the PIN diodes and varactor diodes, the three kinds of linear polarisations and frequency reconfiguration functionalities for 2G/3G/LTE/5G applications can also be easily obtained. With the above-mentioned features, the proposed antenna well suits for intelligent base-station communications. [ABSTRACT FROM AUTHOR]

This paper proposes a dual-band dual-polarized planar antenna array with flat-top and sharp cutoff radiation patterns for 2G/3G/LTE base stations. The array consists of $8 \times 8$ antenna elements arranged with nonuniform spacings and is assigned with optimized nonuniform excitations to achieve flat-top and sharp cutoff radiation patterns with low sidelobes. The radiating element consists of two square-shaped PCB boards. Extra adjustable coupling elements are introduced in the H-shaped patches to improve the impedance matching performance in an array environment as well as to reduce the size of the antenna element. In the 1.71–2.69 GHz band, the dual-polarized radiating element exhibits stable radiation patterns, excellent impedance matching (VSWR < 1.5), and high isolations (>40 dB). Frequency band selective variables are defined to group the antenna elements. They are optimized along with the element spacings and complex excitations in the optimizer to ensure stable flat-top radiation patterns. Rectangular-shaped baffles are introduced to reduce mutual couplings. A prototype of the $8 \times 8$ antenna array has been fabricated and measured. The results indicate that the proposed dual-band dual-polarized planar array achieves a half-power beamwidth of 50° ± 5° in both the H-plane and E-plane. The proposed antenna and its array exhibit attractive potentials for 2G/3G/LTE base station applications. [ABSTRACT FROM AUTHOR]

This paper considers the hidden-node problem in downlink transmission of an LTE-U and WiFi coexistence system operating in unlicensed bands. An enhanced LTE-U node structure is first presented, in which a WiFi module is introduced in an LTE-U eNB, and the RRC and MAC functional blocks in both LTE-U eNB and LTE-U UE are redefined. The purpose is to enable information exchange between an LTE-U node and a WiFi node in order to handle the hidden-node problem. Based on the enhanced LTE-U node structure, an enhanced listen-before-talk (e-LBT) mechanism is further presented, which incorporates an RTS/CTS handshaking procedure in the basic LBT mechanism. To support RTS/CTS handshaking, the relevant information that needs to be exchanged between e-MACWiFi in the WiFi module and e-RRC in the LTE-U module of an LTE-U node is identified, and the message format to be exchanged between e-MACWiFi and e-RRC is defined. Simulation results show that the proposed e-LBT mechanism can significantly improve the performance of the coexistence system in terms of the LTE-U system throughput and WiFi system throughput as compared with the basic LBT mechanism. [ABSTRACT FROM AUTHOR]

In the past, the environmental monitoring was carried out by individual sensors or by people who directly measured and recorded, and these led to muff and inconvenience in a multi-recording. Nowadays, a wireless sensor network (WSN) is popular and applied to many fields, a vehicle can be considered as a dust of the WSN to a ubiquitous realization. If we embedded the sensors module and 3G communication technology into the mobile vehicles, we can be faster and more accurately obtain the status and location of the vehicles to accomplish the real-time monitor. In this paper, the authors combined the temperature/humidity sensor module and the 3G/NFC technology to embed on a vehicle to make the Internet-of-Vehicle (IoV) as a mobile dust that transmissions the measurement value of the temperature and humidity to the servers to realize the cold chain logistics with real-time monitoring. At the same time, we also immediately deliver the status of the temperature and humidity, and the position of the vehicles via the 3G/NFC. Through the experiment, we have proved that the issued IoV with ubiquitous working to be accurate and to reach the goals for freshness and refrigeration of food. [ABSTRACT FROM AUTHOR]

Understanding the temporal traffic load profile of cellular networks is extremely valuable to many network operation tasks in large mobile networks. Such knowledge is useful for network planning, improving network performance, designing better load balancing schemes, testing handoff algorithms, and proposing new charging mechanisms. This paper proposes a simple yet powerful method to model the temporal traffic profile by a large 3G/LTE cellular network dataset in a metropolitan area, consisting of 9 thousand base stations and 3.5 million subscribers. Specifically, using the spectrum-based analysis, we extract three major frequency components, which captures the weekly, daily, and hourly temporal patterns in the traffic load across base stations. By clustering the traffic utilizing the features extracted from spectrum-domain components, we find that urban scale cellular traffic can be classified into five groups, which maps to five types of geographic locations. Besides the comprehensive analysis, we apply this model to two applications: predicting the future traffic load, and designing a load based pricing scheme, where we demonstrate the usefulness of our model and analysis results. [ABSTRACT FROM AUTHOR]

The recent advent of long-read sequencing technologies, such as Pacific Biosciences (PacBio) and Oxford Nanopore technology (ONT), has led to substantial accuracy and computational cost improvements. However, de novo whole-genome assembly still presents significant challenges related to the computational cost and the quality of the results. Accordingly, sequencing accuracy and throughput continue to improve, and many tools are constantly emerging. Therefore, selecting the correct sequencing platform, the proper sequencing depth and the assembly tools are necessary to perform high-quality assembly. This paper evaluates the primary assembly reconstruction from recent hybrid and non-hybrid pipelines on different genomes. We find that using PacBio high-fidelity long-read (HiFi) plays an essential role in haplotype construction with respect to ONT reads. However, we observe a substantial improvement in the correctness of the assembly from high-fidelity ONT datasets and combining it with HiFi or short-reads. • This study evaluates the assembly of the genome of different organisms from hybrid and non-hybrid strategies of assembly. • Assembly using HiFi reads yields genome sequences that are more continuous and complete while being cost-effective. • Through hybrid assembly, the number of translocations can be reduced, thereby increasing genome correctness. [ABSTRACT FROM AUTHOR]

With the multi network cooperative development of 4G, 3G and 2G, it is an essential and important task to comprehensively identify and classify the network optimization scenarios in the light of coverage, services, interference, malfunction and resource allocation from geography dimension on each layer, which can directly have an impact on the programs and strategies of network optimization and planning at each level. Meanwhile, precise identification of network optimization scenarios can bring an important guiding significance to the wireless network scheming, planning and optimization. In the network optimization of different scenarios, even with the same network quality, the parameters selection or adjustment during the optimization process may be different, namely, there should be the different parameter optimization models to match to different environments. Based on machine learning and big data technology, this study analyzes the wireless network multi-dimensional attributes and realize the automate identification and classification for cells under different scenarios. As such, the purpose of quantifying and identifying wireless network scenarios can be achieved. [ABSTRACT FROM AUTHOR]

Deploying femtocells has been taken as an effective solution for removing coverage holes and improving wireless service performance in 3G-beyond wireless networks such as WiMAX and Long Term Evolution (LTE). This article investigates a novel framework of dynamic spectrum management for femtocell networks, called cognitive-empowered femtocells (CEF), aiming at mitigating both cross-tier and intratier interferences with minimum modifications required on the corresponding macrocell network. With the proposed framework, each CEF base station (BS) and the femtocell users can utilize spatiotemporally available radio resources for the access traffic. We conclude that the proposed CEF framework can effectively complement the existing femtocell design and serve as a value-added feature to the state-of-the-art femtocell technologies, while achieving high scalability and interoperability by minimizing the required modifications on the macrocell protocol design. [ABSTRACT FROM AUTHOR]

In this paper, we propose a reconfigurable hardware-friendly VLSI architecture of the radix-2 r based Polar encoder for emerging high-speed 5G system, including single-radix and reconfigurable multi-radix modes. In a single-radix structure, by using TSMC 90 nm CMOS technology, a 16384-point radix-2 based Polar encoder design is synthesized with 0.244 mm 2 under maximum clock frequency of 2.0 GHz. In post-APR ASIC results, the radix-2 based Polar encoder only occupies 0.305 mm 2 and consumes 357.8 mW at maximum clock frequency of 1.61 GHz. The VLSI hardware circuit can be extended to any radix-2 r based design in a similar manner. In a reconfigurable multi-radix structure, a 4096-point 3-mode reconfigurable Polar encoder design is implemented with TSMC 90 nm CMOS technology, only owning a chip layout area of 0.13 mm 2 and consuming 37.2, 32.0, and 26.2 mW in radix-2, radix-4, and radix-8 operating modes, respectively. The benefit of supporting different radix modes is to provide a design trade-off between power consumption and possible Polar encoder size selections. [ABSTRACT FROM AUTHOR]

To meet the explosive growth of mobile data traffic, ultra-dense networks have emerged to enhance spatial and spectral efficiency. Densely deployed small cell architecture faces several major challenges, including low infrastructure utilization ratio, severe inter-cell interference, and so on. In this article, we aim to develop a novel super base station (SupBS) network architecture to tackle these issues. The proposed SupBS architecture consists of two layers, namely, an infrastructure layer and a virtualized network layer. In the infrastructure layer, there are three key physical components: the hybrid heterogeneous radio unit pool, line interface switch unit, and computing resources pool. In the virtualized network layer, there are two logical modules designed on top of the three physical components, namely, the virtualized base station and virtualized software defined core network. The two logical modules are designed to facilitate the use of the underlying three physical components by reducing the energy consumption and processing delay. We present the functionalities of the two virtualized modules and explain how they are utilized to create virtual networks. Moreover, we demonstrate a recently developed SupBS prototype, and provide an application scenario for this prototype in an Internet information broadcast-storage system to show the advantages of our architecture. [ABSTRACT FROM AUTHOR]

The article introduces a method of performing a radio link quality assessment based on the Link Quality Indicator (LQI) which will be calculated for every system that is available. The method presented has been developed during the netBaltic project completed in Poland and generally applies to the so-called maritime zone A, i.e. the sea area where ships are still within the range of shore-based radio communication systems, particularly 3G/LTE cellular networks. The algorithm was developed based on the results of measurements obtained during two separate campaigns. That measurement data served as a basis for the method's initial assumptions and was utilized during the method's verification. [ABSTRACT FROM AUTHOR]

Mobile communication systems experienced high technical revolution. Nowadays, smart mobile devices have advanced computing aspects. In addition, they are provided with multiple network interfaces, wifi and 3G. Traffic redirection between these networks is addressed by the vertical handover process. Recently, vertical handover enhanced by the IEEE802.21 standards which enables seamless mobility and interworking between most of the heterogeneous wireless access networks [2]. A comparative performance study is done in this paper for the integration between WiFi and UMTS networks by taking advantage of the IEEE802.21 standard. The factors that affect the vertical handover process in this integration were studied such as the mobile speed, and the application bitrate. Selecting five mobile node speeds 5,10,25,50,60 km/h whereas application bitrate is 64 kb/s and 3840 kb/s. [ABSTRACT FROM AUTHOR]

5G system design is a complex process due to a great variety of applications and their diverse requirements. This article describes our experiences in developing a centimeter waves mobile broadband concept satisfying future capacity requirements. The first step in the process was the radio channel measurement campaign and statistical modeling. Then the link level design was performed tightly together with the radio frequency (RF) implementation requirements to allow as large scalability of the air interface as possible. We started the concept development at 10 GHz frequency band and during the project World Radiocommunication Conference 2015 selected somewhat higher frequencies as new candidates for 5G. Thus, the main learning was to gain insight of interdependencies of different phenomena and find feasible combinations of techniques and parameter combinations that might actually work in practice, not only in theory. [ABSTRACT FROM AUTHOR]

A broadband ±45° dual-polarized multidipole antenna is proposed in this communication. A pair of big dipoles and a pair of small ones are printed on a square substrate. The large dipoles mainly dominate the low operating frequency of the antenna, while the small dipoles work at the high one. A pair of H-shaped coupler is introduced to feed the antenna through capacitive coupling with loop radiator dipoles, and a rectangular box-shaped reflector is used for keeping the radiation patterns over the operating frequency. The antenna achieved a wide impedance bandwidth of about 56.6% for < 1.5 at both ports, covering the frequency range from 1.66 to 2.97 GHz. Over the operating frequency, a gain >8.1 dBi is achieved for both ports. A stable radiation pattern with 3 dB beamwidth 62°±6° at E-plane and 75°±3° at H-plane for port 1 and 60° ±4° at E-plane and 71° ±5° at H-plane for port 2 is obtained. The antenna is manufactured and tested. The measured results of the antenna are in well agreement with the simulation ones. Design details of the proposed antenna are presented and discussed. [ABSTRACT FROM PUBLISHER]

This paper presents a geometry-based stochastic channel model (GSCM) for a 3GPP millimeter-wave (mmWave) high-speed train (HST) scenario. An important demand of the mmWave HST channel model is the spatial consistency during movement. In order to meet this requirement, the environment pattern containing the most effective geometry information is proposed, which is useful for generating an integral and accurate channel geometry. Since the measurement of a mmWave channel is deficient for high mobility, the proposed channel model is developed using a ray-tracing (RT) simulator that is validated with the channel measurements performed in the HST scenario at 93.2 GHz. The paper gives a full parameterization for the proposed model and its implementation for channel simulation. The verification is made through a comparison of the proposed model and the measurement-validated RT simulations in terms of the power delay profile, the Ricean $K$-factor, and the second-order statistics for the delay and angle domains. Finally, for the design of mmWave HST communication systems, the time-varying channel characteristics are evaluated in the delay and Doppler domains. [ABSTRACT FROM PUBLISHER]

The growing complexity of heterogeneous cellular networks (HetNets) has necessitated a variety of user and base station (BS) configurations to be considered for realistic performance evaluation and system design. This is directly reflected in the HetNet simulation models proposed by standardization bodies, such as the 3rd Generation Partnership Project (3GPP). Complementary to these simulation models, stochastic geometry-based approach, modeling the locations of the users, and the $K$ tiers of BSs as independent and homogeneous Poisson point processes (PPPs), has gained prominence in the past few years. Despite its success in revealing useful insights, this PPP-based K$ -tier HetNet model is not rich enough to capture spatial coupling between user and BS locations that exists in real-world HetNet deployments and is included in 3GPP simulation models. In this paper, we demonstrate that modeling a fraction of users and arbitrary number of BS tiers alternatively with a Poisson cluster process (PCP) captures the aforementioned coupling, thus bridging the gap between the 3GPP simulation models and the PPP-based analytic model for HetNets. We further show that the downlink coverage probability of a typical user under maximum signal-to-interference-ratio ( \mathtt {SIR} ) association can be expressed in terms of the sum-product functionals over PPP, PCP, and its associated offspring point process, which are all characterized as a part of our analysis. We also show that the proposed model converges to the PPP-based HetNet model as the cluster size of the PCPs tends to infinity. Finally, we specialize our analysis based on general PCPs for Thomas and Matérn cluster processes. Special instances of the proposed model closely resemble the different configurations for BS and user locations considered in 3GPP simulations. [ABSTRACT FROM PUBLISHER]

With the mobile industry dramatically scaling over the last decade, this paper provides an empirical service and marketing model on the determinants of customers’ decision to stay loyal to their 3G mobile data service (MDS) providers in an emerging market in sub-Saharan Africa. The introduction of fourth-generation MDS into the Ghanaian telecommunications industry has brought intense competition among industry players. As a result, we examined factors that influence 3G customers’ loyalty towards their service provider in an emerging market using data collected from 235 third-generation MDS users. Findings from our partial least square – structural equation modelling analysis indicated that the effects of service quality on trust and satisfaction were significant, subsequently impacting loyalty. Interestingly, our results showed a significant effect of corporate image on trust, but not on satisfaction and loyalty. Our results should help MDS providers by improving strategies on customer retention and loyalty in order increase their market share and profitability. [ABSTRACT FROM PUBLISHER]

Nowadays, satellites are becoming increasingly software dependent. Satellite Flight Software (FSW), that is to say, the application software running on the satellite main On-Board Computer (OBC), plays a relevant role in implementing complex space mission requirements. In this paper, we examine relevant technical approaches and programmatic strategies adopted for the development of the Meteosat Third Generation Satellite (MTG) FSW. To begin with, we present its layered model-based architecture, and the means for ensuring a robust and reliable interaction among the FSW components. Then, we focus on the selection of an effective software development life cycle model. In particular, by combining plan-driven and agile approaches, we can fulfill the need of having preliminary SW versions. They can be used for the elicitation of complex system-level requirements as well as for the initial satellite integration and testing activities. Another important aspect can be identified in the testing activities. Indeed, very demanding quality requirements have to be fulfilled in satellite SW applications. This manuscript proposes a test automation framework, which uses an XML-based test procedure language independent of the underlying test environment. Finally, a short overview of the MTG FSW sizing and timing budgets concludes the paper. [ABSTRACT FROM AUTHOR]

The 3GPP is in the process of developing the next generation radio access technology, named New Radio (NR), which will be proposed as a candidate technology for IMT-2020. This article outlines the wide bandwidth operation of NR, among other new features being considered, based on the up-to-date discussions and decisions made in 3GPP standardization meetings. The much wider channel bandwidth of NR, compared to LTE, enables more efficient use of resources than the existing carrier aggregation framework with lower control overhead. The support of multiple sub-carrier spacing options allows NR to operate in a wide range of carrier frequency from sub-6 GHz band to mmWave band with appropriate handling of multi-path delay spread and phase noise depending on the carrier frequency. In addition, the introduction of the new bandwidth part concept allows flexible and dynamic configuration of UE's operating bandwidth, which will make NR an energy-efficient solution despite the support of wide bandwidth. Other NR wideband operation related issues, such as the support of UEs with limited RF capability and frequency domain resource indexing, are also explained in this article. [ABSTRACT FROM AUTHOR]

This paper presents a new kind of highly flexible frequency-agile bandpass filters (FA-BPFs) based on the novel synchronously tuned dual-mode resonator (STDR). The bandwidth (BW), BW variation tendency, passband selectivity (stopband rejection level), and frequency tuning range of the filter can be predefined individually. Benefiting from the unique characteristics of the STDR, the FA-BPF with very simple and highly flexible design/control procedures is achieved. Due to the proposed geometry, two self-adaptive transmission zeros are introduced and move with the passband. The predefined mechanism is investigated in detail, and the simple design and predefined procedures are summarized. Then, three 0.75–1.7 GHz single-band examples with elliptic response are developed to achieve three predefined absolute BWs (ABW). The design techniques and filter superiority are confirmed by the experiments. Moreover, aiming at China 2G/3G/4G cellular wireless/mobile communication system (up to band 40:0.825–2.65 GHz), a novel intrinsically switchable single-/dual-band FA-BPF is presented based on the proposed STDR. An example with a constant ABW1 dB and a fractional bandwidth1 dB (FBW1 dB is designed to validate the theory and analysis. The FA-BPF is able to operate as a highly selective dual-band FA-BPF with 0.76–1.78 GHz/1.61–2.63 GHz tuning ranges, and also can be switched to single-band operation with the continuous tuning range of 0.76–2.63 GHz. [ABSTRACT FROM PUBLISHER]

In this paper, the strength of data confidentiality and integrity algorithms used in 3rd Generation Partnership Project (3GPP) mobile communication technologies are improved. KASUMI is a block cipher, which consists of eight Feistel rounds with a 128 - bit key. The confidentiality and integrity of 3G mobile communications systems depend on the security of KASUMI, which has been in place for more than 10 years. Literature survey reveals that it is possible to break KASUMI with a related key attack and very modest computational resources. To overcome the thread against the security attack, we proposed modification in the conventional KASUMI block cipher by inserting the finite state machine (FSM) followed by Rijndael S-box (SR and SQ) at the end of the 7th round. The simulation results are provided in-terms of encryption speed and encryption time taken to show that the proposed modification in KASUMI does not affecting the speed of the encryption. [ABSTRACT FROM AUTHOR]

Vertical restrictions have theoretically ambiguous efficiency effects. Marketplace evidence is, therefore, required to reveal the presence of anticompetitive foreclosure. The bundling of mobile phones with cellular network service offers one such market test. One EU member, Finland, prohibited tying arrangements for mobile service and mobile handsets in wireless broadband markets, and then cleanly ended this prohibition in April 2006. We compare the growth in Finnish third-generation (3G) uptake against other European markets using quarterly data from first quarter 2006 through fourth quarter 2012. An output effects model adjusting for market-specific factors suggests 3G penetration growth in Finland increased substantially following market reform. [ABSTRACT FROM AUTHOR]

Machine Type Communication (MTC), as one of the most important wireless communication technologies in the future wireless communication, has become the new business growth point of mobile communication network. It is a key point to achieve seamless handovers within Evolved-Universal Terrestrial Radio Access Network (E-UTRAN) for massive MTC (mMTC) devices in order to support mobility in the Long Term Evolution-Advanced (LTE-A) networks. When mMTC devices simultaneously roam from a base station to a new base station, the current handover mechanisms suggested by the Third-Generation Partnership Project (3GPP) require several handover signaling interactions, which could cause the signaling load over the access network and the core network. Besides, several distinct handover procedures are proposed for different mobility scenarios, which will increase the system complexity. In this paper, we propose a simple and secure uniform group-based handover authentication scheme for mMTC devices based on the multisignature and aggregate message authentication code (AMAC) techniques, which is to fit in with all of the mobility scenarios in the LTE-A networks. Compared with the current 3GPP standards, our scheme can achieve a simple authentication process with robust security protection including privacy preservation and thus avoid signaling congestion. The correctness of the proposed group handover authentication protocol is formally proved in the Canetti-Krawczyk (CK) model and verified based on the AVISPA and SPAN. [ABSTRACT FROM AUTHOR]

Distributed clouds offer a choice of data center locations for providers to host their applications. In this paper, we consider distributed clouds that host virtual desktops which are then accessed by users through remote desktop protocols. Virtual desktops have different levels of latency-sensitivity, primarily determined by the actual applications running and affected by the end users’ locations. In the scenario of mobile users, even switching between 3G and WiFi networks affects the latency-sensitivity. We design VMShadow, a system to automatically optimize the location and performance of latency-sensitive VMs in the cloud. VMShadow performs black-box fingerprinting of a VM’s network traffic to infer the latency-sensitivity and employs both ILP and greedy heuristic based algorithms to move highly latency-sensitive VMs to cloud sites that are closer to their end users. VMShadow employs a WAN-based live migration and a new network connection migration protocol to ensure that the VM migration and subsequent changes to the VM’s network address are transparent to end-users. We implement a prototype of VMShadow in a nested hypervisor and demonstrate its effectiveness for optimizing the performance of VM-based desktops in the cloud. Our experiments on a private as well as the public EC2 cloud show that VMShadow is able to discriminate between latency-sensitive and insensitive desktop VMs and judiciously moves only those that will benefit the most from the migration. For desktop VMs with video activity, VMShadow improves VNC’s refresh rate by 90% by migrating virtual desktop to the closer location. Transcontinental remote desktop migrations only take about 4 min and our connection migration proxy imposes 13 μs overhead per packet. [ABSTRACT FROM AUTHOR]