Generation Mobile Applications Research Articles

A Modified Polygon Shaped Microstrip Patch Antenna Array for Ultra-Wideband Applications

A single element and two elements array polygon shape microstrip antenna is proposed and analyzed in this paper for ultra-wideband (UWB) applications. The technique used to improve antenna performance is etching rectangular slots on the patch of the antenna with different dimensions and positions. Two Polygon Shape antenna patches are introduced to enhance the antenna properties. Also, multi-slots are reached to improve the antenna gain, impedance matching sweep parameter optimization technique is used to all antenna parameters to enhance antenna properties. The dimensions of the single element antenna are 30 x 33 mm2 and consist of a slotted polygon patch printed on an FR-4 substrate. The proposed antenna has a resonant frequency of 6.2 GHz, while the dimensions of two elements antenna array are 60 x 33 mm2 and the resonance frequency is 9.8 GHz. A technique of inset feed transmission line was utilized to match the 50 Ω microstrip feed line and the radiating patch. These considerations make the structure is suitable for fifth-generation generation (5G) mobile wireless applications. The proposed antenna was simulated by use Computer Simulation Technology (CST-2020) software.

A Low Cross-Polarization Microstrip Antenna Array for Millimeter Wave Applications

A low cross-polarization microstrip antenna array for millimeter wave (mmW) applications is proposed in this paper. The antenna element is composed of symmetric T-shaped patches with vias. The adoption of a double-sided symmetric radiation patch structure can suppress the cross-polarized electric field, and the vias reduces energy leakage during the power transmission along the antenna patches. To verify the concept, a 1 × 8 antenna array is fabricated and measured. The measured −10 dB impedance of the antenna array is 28.4% (31 GHz–41.5 GHz) and the peak gain is 15 dBi. The cross polarization ratio is above 35 dB and the 3 dB beamwidths on E-plane and H-plane are 7.5° and 135°, respectively. The proposed compact size and low cross-polarization antenna array might be a good choice for phased array radar and 5th generation (5G) mobile communication applications.

Multiple input multiple output (MIMO) and fifth generation (5G): an indispensable technology for sub-6 GHz and millimeter wave future generation mobile terminal applications

AbstractThe in-depth exploration in the future 5G technology symbolizes a revolution in technology for antenna designers to encounter the all time increasing need as well as demand for higher data rate wireless communications. The paper gives out an exhaustive review of the evolution and characteristics of the 5G spectrum allocations, the MIMO antenna design with regard to mutual coupling reduction techniques and safer user applications. It precisely covers almost all the aspects of 5G which mainly include the types of antenna designs and their performance parameters related to MIMO design. The paper also presents a brief description of massive MIMO technology for base station applications. The main aim of the paper is: (1) to emphasize the frequencies allocated for the 5G including sub-6 Ghz and mm-wave bands; (2) to underline the suitable antenna designs for MIMO applications for mobile devices and base stations; (3) to highlight the mutual coupling effects in MIMO designs and its reduction techniques; (4) to consider the gaps in the literature and the challenges for reducing SAR effects for the safety of the users. This review paper has been an attempt to explore the evolution of 5G bands and antenna designs for 5G applications, comparison based on the literature, and the techniques implemented for enhancing the MIMO antenna performances.

Automatic Positioning of Mobile Users via GSM Signal Measurements

Today the need for mobile communication systems and the high increase in the number of users have also made the development of new generation mobile applications indispensable. Obtaining location information has been one of the most interesting and significant areas of improvement. The purpose of the services used to determine the location is generally to obtain the information of the users such as approximate location, speed and time. The GPS system is the most preferred and globally accurate positioning system among global positioning systems. However, in addition to requiring a high installation cost of this system, it is one of the biggest constraints that galactic and meteorological factors, high buildings and other physical obstacles, and especially closed areas can lead to serious signal weaknesses and losses which may cause the system to be out of service. Considering these issues, it is seen that there is an urgent need for positioning systems that will be alternative and complementary to global positioning systems. The cellular network is widely used by almost everyone and its coverage area is increasing day by day. The employed data sets were created by recording the received signal strength (RSS), location information of the GSM base station and the user measured in indoor and outdoor areas through a mobile application we have developed in the Android Studio environment for mobile phones. The network has been trained by machine learning algorithms; extreme learning machine (ELM), generalized regression neural network (GRNN) and k nearest neighborhood (kNN). In the tests conducted with indoor, outdoor and combined data sets, it has been observed that the proposed positioning system works well with distance error rates below a meter (m) at the minimum, and between 76-216 m on average.

Exploring engagement among mobile app developers – Insights from mining big data in user generated content

PurposeThe Web 3.0 has been hugely enabled by smartphones and new generation mobile applications. With the growing adoption of smartphones, the use of mobile applications has grown exponentially and so has the development of mobile applications. This study is an attempt to understand the issues and challenges faced in the mobile applications domain using discussions made on Twitter based on mining of user generated content.Design/methodology/approachThe study uses 89,908 unique tweets to understand the nature of the discussions. These tweets are analyzed using descriptive, content and network analysis. Further using transaction cost economics, the findings are reviewed to develop practice insights about the ecosystem.FindingsFindings indicate that the discussions are mostly skewed toward a positive polarity and positive user experiences. The tweeters are predominantly application developers who are interacting more with marketers and less with individual users.Research limitations/implicationsMost of these applications are for individual use (B2C) and not for enterprise usage. There are very few individual users who contribute to these discussions. The predominant users are application reviewers or bloggers of review websites who use the recently developed applications and discuss their thoughts on the same.Practical implicationsThe results may be useful in varied domains which are planning to expand their reach to a larger audience using mobile applications and for marketers who primarily focus on promotional content.Social implicationsThe domain of mobile applications on social media is still restricted to promotions and digital marketing and may solely be used for the purpose of link building by application developers. As such, the discussions could provide inputs towards mobile phone manufacturers and ecosystem providers on what are the real issues these communities are facing while developing these applications.Originality/valueThe study uses mixed research methodology for mining experiences in the domain of mobile application developers using social media analytics and transaction cost economics. The discussion on the findings provides inputs for policy-making and possible intervention areas.

Multiantennas conjoined with metal frame and integrated into 8 × 8 m ultiple‐input and m ultiple‐output array for fifth generation smartphone applications

A new multiple-input and multiple-output (MIMO) antenna conjoined with a metal case and metal frame in mobile phones for fifth generation mobile network applications is presented. The main antenna is the metal frame inverted-F antenna (IFA) with a high-pass circuit (HPC) on the short side of the phone (Ant. 1); then, the system ground extending path and coupling are used to create a semi-slot antenna (Ant. 2). The metal frame radiating monopole antenna (Ant. 3) uses a low-pass circuit, and the IFA antennas (Ant. 4) with HPCs are placed in a clear space only 1-mm wide on the long side of the phone. To improve the isolation of the multiple antennas, the configuration of the MIMO antenna integration was investigated. The proposed four- or eight-MIMO array was comprehensively evaluated in the desired band. The characteristics of individual antennas were used to achieve pattern diversity, and they demonstrated good performance in channel capacity evaluation: 19.4 bps/Hz (four-antenna MIMO) and 38.6 bps/Hz (eight-antenna MIMO).

Design and simulation of millimeter wave reconfigurable antenna using iterative meandered RF MEMS switch for 5G mobile communications

This paper present the design and simulation of a circular patch antennas integrated with low pull in voltage novel iterative meander RF MEMS switch. The transmitting signal can be alternatively switch from 40 to 60 GHz by actuating the switch beams placed on the feeding line of patch antenna. The switch—B is actuated to allow the RF (radio frequency) signal to pass through switch—A to radiates the signal at 40 GHz and it is vice versa for the signal is radiating at 60 GHz. This type of antenna is used for future 5G (5th generation) mobile communication applications. The switch utilizes 1.6 V of actuation voltage and 1.63 µs (micro seconds) of transition time to displace the beam from upstate to downstate. It exhibits very low return loss and insertion losses of − 56 dB (decibels) and − 0.19 dB at 40 GHz (gigahertz), respectively and shows high isolation of − 37.5 dB at 45 GHz such that efficiently used for millimeter wave applications. The two circular patch antennas are designed at 40 GHz and 60 GHz shows good performance characteristics and are alternatively switch between them when signal conjunction occurs. The characteristics of switch and antennas are studied by using FEM (finite element modeling) tools such as COMSOL, HFSS 13.0 V and CST 15.0 V and tunability of the antenna is achieved efficiently for 5G mobile applications.

A Novel 28 GHz Beam Steering Array for 5G Mobile Device With Metallic Casing Application

The design of a novel practical 28 GHz beam steering phased array antenna for future fifth generation mobile device applications is presented in this communication. The proposed array antenna has 16 cavity-backed slot antenna elements that are implemented via the metallic back casing of the mobile device, in which two eight-element phased arrays are built on the left- and right-side edges of the mobile device. Each eight-element phased array can yield beam steering at broadside and gain of >15 dBi can be achieved at boresight. The measured 10 dB return loss bandwidth of the proposed cavity-backed slot antenna element was approximately 27.5–30 GHz. In addition, the impacts of user’s hand effects are also investigated.

A Fully Biobased Encapsulant Constructed of Soy Protein and Cellulose Nanocrystals for Flexible Electromechanical Sensing

Presently, flexible electromechanical sensors are of particular interest to next generation mobile applications. To enrich the flexible encapsulants, herein, a fully biobased film is developed by cross-linking soy protein isolate (SPI) with nanocross-linker, aldehyde-bearing, cellulose nanocrystals (CNC). Thanks to the enhanced interfacial interaction between SPI and CNC resulting from the Maillard reaction, the protein-rich phase becomes more homogeneous with smaller domain size. Compared with neat SPI film, the resultant composite films exhibit an obviously improved mechanical property and water resistance. In particular, the heat-sealing property of such films is well maintained, which guarantees their application as encapsulation layers to construct flexible electromechanical sensors. These results indicate that green composite films hold promising applications as universal encapsulation materials for integrating flexible movement-monitoring electronics.

LBRW

Location-based social networks (LBSNs) have witnessed a great expansion as an attractive form of social media. LBSNs allow users to “check-in” at geographical locations and share this information with friends. Indeed, with the spatial, temporal and social aspects of user patterns provided by LBSNs data, researchers have a promising opportunity for understanding human mobility dynamics, with the purpose of designing new generation mobile applications, including context-aware advertising and city-wide sensing applications. In this paper, the authors introduce a learning based random walk model (LBRW) combining user interests and “mobility homophily” for location recommendation in LBSNs. These properties are observed from a real-world Location-Based Social Networks (LBSNs) dataset. The authors present experimental evidence that validates LBRW and demonstrates the power of these inferred properties in improving location recommendation performance.

A Survey of Mobile Cloud Computing Applications: Perspectives and Challenges

As mobile computing has been developed for decades, a new model for mobile computing, namely, mobile cloud computing, emerges resulting from the marriage of powerful yet affordable mobile devices and cloud computing. In this paper we survey existing mobile cloud computing applications, as well as speculate future generation mobile cloud computing applications. We provide insights for the enabling technologies and challenges that lie ahead for us to move forward from mobile computing to mobile cloud computing for building the next generation mobile cloud applications. For each of the challenges, we provide a survey of existing solutions, identify research gaps, and suggest future research areas.

Planar monopole antennas for new generation mobile and lower band ultra-wide band applications

This study presents two multiband planar printed monopole antennas with an optimised size of 57×37.5×0.8 mm3 for mobile/wireless and low-band ultra-wide band (UWB) applications. Both these antennas are constructed as a chorded crescent-shaped radiator, a feed line and a defected ground plane. The experimental and computed results confirm that one design offers a wide usable impedance bandwidth of 114.3%, with a reflection coefficient |S11|<−10 dB, over 1.5–5.5 GHz. The other incorporates a tapered sickle-shaped slot in the radiator and demonstrates a band-suppression feature giving rejection of the worldwide interoperability for microwave access band (3.4–3.69 GHz) where this is not required. The gains and far-field patterns of the antennas are presented and their group delay over the lower band UWB frequency range is also discussed.

A printed coupled‐fed loop antenna with two chip inductors for the 4G mobile applications

AbstractThis article proposes a meandered printed loop antenna for the fourth generation (4G) mobile system applications. Using a coupling strip connected with a 50 Ω microstrip fed‐line on front side, the loop antenna on back side is excited and a half wavelength (0.5 λ) resonant mode and its higher modes are successfully resonated. A plane copper strip connected at top of the loop antenna is used to increase the antenna's path and to decrease the lower operation band to cover LTE 700 band. Two 15 nH ceramic chip inductors, which are embedded in the loop antenna, are used to decrease the antenna's 1 and 1.5 λ resonant modes. The 0.5, 1, and 1.5 λ resonant modes get together to form a broad lower operation band (693–1031 MHz) for LTE 700 and GSM 850/900 applications. Beside, the antenna's higher resonant modes are also excited to form a broad higher operation band (1668–2781 MHz) for DCS, PCS, UMTS, LTE 2300, LTE 2500, and WLAN applications. The proposed antenna also has an advantage of small size, which is 114 × 50 mm2 including a loop antenna of 14 × 50 mm2 and a ground plane of 100 × 50 mm2. With the advantages of board band, compact size, low cost, and good performance, the proposed antenna appears to be an optimal candidate for the 4G mobile applications. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2157–2163, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26997

Evaluation of IP Multimedia Subsystem based Mobile Mass Examination System

This research is carried out to develop IP Multimedia Subsystem (IMS) based Mobile Mass Examination (MoMEx) System. MoMEx system is intended to improve on management of examination process for large number of examinees. IMS based application is considered to be the next generation mobile applications that enable developers to take advantage of mobile networks resources. IMS-based application is attributed with robustness and improved Quality of Experience (OoE) for mobile users. Such quality is needed to ensure users reliabilities on the system. In This paper, we cover the analysis and design phase of MoMEx system. We have designed set of questionnaires aimed to gathering insights how much the concept of mobile exam and assessment will be accepted among the students and faculty members. Based on the results obtained, we concluded the functional requirements of MoMEx system prior to implementation phase.

A coupled‐fed loop antenna for fourth generation mobile system applications

AbstractThis article proposes a compact printed meander loop antenna for the fourth generation (4G) mobile system applications.The total length of the meander loop operates a one‐wavelength resonant mode (mode 1) at 774 MHz. To increase the antenna's operation bandwidth, this article uses coupled‐fed feeding method that contains a coupling patch connected with a 50‐Ω microstrip feed line. By applying the coupled‐fed method, a new one‐wavelength resonant mode (mode 2) is excited. After carefully adjusted the size of coupling patch, the frequency of mode 2 shifts to 904 MHz combining with mode 1 to form dual broad operations bands. The measured dual broad bands from 658 to 963 MHz and from 1658 to 2693 MHz can be applied in the 4G mobile system, especially for the long‐term evolution application. The two resonant modes are resonated by 1λ loop type that has less influence by changing the size of ground plane. The antenna portion and overall dimensions of the proposed antenna are 20 × 60 × 0.8 mm3 and 120 × 60 × 0.8 mm3 suitable for today's mobile phone application. With the advantages of board band, compact size, low cost, and good performance, the proposed antenna appears to be a promising candidate for the 4G mobile applications. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1900–1907, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26927

차세대 이동 통신용 다중 안테나 시스템

In this paper, a multiple antenna system for next generation mobile applications is proposed. The proposed MIMO antenna consists of two parallel folded monopole antennas with the length of 100 mm and spacing of 6 mm and a decoupling network which locates at the top side of a mobile handset. In order to improve the isolation characteristic at the LTE band 13, a decoupling network was added between the two antenna elements placed close to each other. The decoupling network, consisting of two transmission lines, a shunt reactive component and common ground line, is simple and compact. To obtain the wide bandwidth characteristic, an wide folded patch structure generating the strong coupling between feeding and shorting lines through the slit is used at the bottom side of a mobile handset. Also, the performance of a multiple antenna system composed of three antenna elements is analyzed.

Multiband MIMO antenna with independent resonance frequency adjustability

AbstractA compact multiband multiple‐input multiple‐output (MIMO) antenna with a band stop matching circuit for next generation mobile applications is proposed. The proposed multiband MIMO antenna consists of two dual‐band planar inverted‐F antennas, which provide wideband characteristics. To improve the isolation characteristic at the long term evolution band, a band stop matching circuit was inserted at the corner of each antenna element. The proposed MIMO antenna has isolation of ∼15 dB at the lower band and over 20 dB at the upper band. In addition, the resonant frequencies of the proposed MIMO antenna can be independently tuned by changing the value of the inductor or by adjusting the widths of Slit1 and Slit2. To evaluate the performance of the proposed antenna, key performance parameters such as total efficiency, envelope correlation coefficient, mean effective gain (MEG), and the MEG ratio are analyzed. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1893–1901, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25334

An Investigation of Third Generation (3G) Mobile Technologies and Services

The objective of this paper is to evaluate the underlying paradigms of third generation (3G) mobile services. Given the success of second generation (2G) mobile communications systems and services, the third generation mobile networks and applications are faced with a lot of expectations such as providing ubiquitous access to online services via mobile terminals. However, 3G technologies and applications have encountered obstacles that have hindered both the technology development and user acceptance. This paper reviews existing literature related to 3G and develops a framework that presents the factors that contribute to the success of 3G. The findings provide insight into the development and marketing of 3G services.

Wideband Planar Antenna for New Generation Mobile Applications

A wideband, compact planar monopole antenna having a 2 : 1 VSWR bandwidth of 98% (1.68 GHz–4.9 GHz) is presented. The omnidirectional radiation pattern with moderate gain and linear polarization in the entire band makes the antenna an excellent candidate for new generation mobile applications. Details of the antenna design and a comparison of simulated and measured results are presented and discussed.

Network layer access control for context-aware IPv6 applications

As part of the Lancaster GUIDE II project, we have developed a novel wireless access point protocol designed to support the development of next generation mobile context-aware applications in our l...