Mobile Personal Communication Research Articles

Optimization of Transmission Lost for Energy Saving Glass with Different Sheet Resistance Values

Recently, energy saving glass is commonly applied in the modern engineered building. This is due to its advantages of keeping the heat inside the building in winter while rejecting the heat when in summer. The typical energy saving glass is made by applying a very thin metallic oxide such as silver oxide or tin oxide on one side of the float glass. But at the same time, it has the disadvantages of attenuates useful microwave frequencies that ranging from 0.8 2.2 GHz. The examples of the microwave frequency at this range are GSM mobile signal, GPS and personal communication. Frequency selective surface (FSS) has been introduced to overcome this drawback of energy saving glass. In this study, the transmission of the microwave signal is observed through the simulation using Computer Simulation Technology Microwave Studio. Bandpass frequency selective surface of cross dipole shape is used for the simulation. In the simulation, conductivity and electrical properties of glass and metal oxide thin film are important. The microwave transmission was evaluated at various sheet resistance of metal oxide thin film. The results show that the minimum transmission lost increased with the ohmic resistance increased. On the other hand, the peak frequency at various sheet resistance shows constant value at around 1.25-1.30 GHz. The full width half maximum of the microwave transmission increases with the sheet resistance value. The results suggest that FSS structured metal oxide thin film with lowest sheet resistance transmits more signal in the range for GSM phone signal.

Identifying the Stay Point Using GPS Trajectory of Taxis

With the widespread use of personal mobile communications location-aware devices, a large amount of data of trajectory produced and can be used in information services. These huge amounts of data involves the pattern of human behavior information and cause numerous researchers' research interests. As is known,the key to travel information mining from the trajectory data is the stay point recognition and semantic annotation.Overcoming the shortcomings on adaptability and resistance to noise exists in existed stay points identification methods, and also combined with the basic characteristics of the taxi GPS data,We proposed a way with an parameter optimization stratage to get the stay points from a single trajectory and the figure shows it really works well, with high precision and strong adaptability on the recall ratio and precision ratio.And then,based on this significant achievements,we applies a refined clustering method based on the clustering radius and frequency parameters and get the POI results.

MOBILE APPLICATIONS AS TOOL FOR EXPLOITING CULTURAL HERITAGE IN THE REGION OF TURIN AND MILAN

Abstract. The current research aims at showing as applications working on personal mobile communication terminals such as smartphones, can be useful for exploration of places and, at the same time, as tools able to develop interaction between cultural heritage and users. In this sense, the use of smartphone applications can be combined with GIS in order to make a platform of knowledge useful to support research studies in the field of cultural heritage, with specific reference to accessibility issues and to the combined use of integrated technologies like GPS, QR code and GIS, with the final aim to find an useful methodology for collecting data by visitors and visualizing them through mapping techniques. The research shows how the integration of different systems and technologies can be used as method for inquiring the interactions between users and cultural heritage in terms of accessibility to places. GPS devices can be used to record visitors movements (cultural routes) in terms of space and time; QR code can be used for users interaction with cultural heritage (tourists opinion, heritage ranking, facilities, accessibility); GIS software can be used for data management, analysis and mapping (tourist flows, more visited places). The focus of research is about a combination of information related to cultural routes with the information related to single cultural places. The focus of research is about a combination of information related to cultural routes with the information related to single cultural places. The current research shows the potential use of smartphone applications, as mobile device for collecting data, as means to record rides and more visited places by tourists. The research could be divided into three steps; the first one concerns with GPS that can be used to record routes; the second one deals with interaction between tourists and cultural heritage through a system based on QR code; the third one is about GIS, used as tool for management, analysis and visualization of data flows. In the current research, the field of investigation refers both to the territorial scale of Turin – Milan axis, and to the local scale of small cities localized in the territories in between. The research has been applied to Turin – Milan infrastructural axis, with the aim to represent the relationships that can be established between mobility infrastructure and cultural heritage. Such relationships should be intended in terms of accessibility from mobility infrastructure (motorway exit, service areas, railways stations) to cultural heritage localized in the surrounding landscape. The richness of cultural heritage and landscape along the chosen infrastructural bundle represent a great opportunity for territorial development in terms of attractiveness, both for local inhabitants and for tourists. Nowadays, the use of tracking technologies can be applied to investigate tourist flows, behaviors of local inhabitants in the historic city centre, number of visitors in the city and so on. In this sense it is possible to apply these technologies, which are particularly relevant in urban studies, extending them to the territorial scale of the Turin – Milan region. The large amount of available geo-referenced data can be used in different ways and it is very potential for different kind of analysis: it is possible to show tourist flows in the territory, receive information about more visited places, obtain interaction from users and cultural heritage in terms of visitors opinion about the places, give information to tourists about cultural places, monitor the accessibility to the places, understand the use of means of transport and keep under control the impacts of tourism (social, cultural, environmental) on territory. Applications based on smartphones can be considered a powerful device for visitors but also for institutions that are involved in tourism and cultural heritage management. In fact, the use of mobile applications it can produce a real time data exchange between geographical position of users and system that receives data. The research shows the opportunity to use GPS and QR code, integrated in a single smartphone application, with GIS software. In the current step of the research only the interaction with GPS and GIS has been tested on the case study of Turin – Milan. Further development of research could be realized to test the real integration of QR code with other systems, developing an application that supports QR code and GPS, and installing a barcode or other interactive devices such as NFC (Near Field Communication) on each relevant cultural places. It is evident that different actors, such as tourists, cultural heritage institutions and employers, have to be involved in this process, in order to have a deeper understanding of the problem, also integrating bottom up and top down contributions.

CPW-FED slot antenna for personal mobile communication service (PCS) and bluetooth applications

A novel design of dual band CPW-fed slot for personal communication service (PCS) and Bluetooth applications is presented in this article.The proposed antenna is designed to operate at 1.8 GHz, 2.4 GHz, and it is fabricated on the FR4 substrate. In this structure, by cutting a pair of G-shaped slits in the ground plane we can gave a new resonance at lower frequencies for PCS in handy terminal, which operating at 1.77∼1.88 GHz band, also by embedding a pair of E-shaped slits at radiating stub, the presented antenna can be created and achieves good dual-band operation. The measured impedance bandwidth for l0 dB return loss is from 1.73 to 1.84 GHz and 2.33 to 2.45 GHz, covering the 1.8/2.4 GHz for PCS/Bluetooth applications. Simulated and experimental results obtained for this antenna show that the proposed slot antenna has a good antenna gains and radiation behavior within the 1.8/2.4 GHz frequencies. The designed antenna has a small size of 30 × 30 × 0.8 mm3. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:734–737, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27432

Simulation of Charge Transfer Process in a 2DEG-CCD

This paper describes the modeling and simulation charge transfer process of a 2DEG charge coupled device. We have introduced a new approach to calculate the scattering rate of two-dimensional electron gas in the transport channel of a 2DEG-CCD. This technique was applied to the investigation of the charge transfer process with ensemble Monte Carlo method. I. I NTRODUCTION Charge Coupled Devices made on silicon have found wide application in imaging and signal processing. These applications have a low-speed operations but, the CCDs for microwave frequency are not suitable. Hetero-junction CCDs, have been demonstrated to have many advantages over earlier silicon and GaAs structures because of their higher low-field mobility and saturation velocity. The operation of these structures are limited only by the saturation velocity of the carriers which results in an upper frequency limit of approximately 40GHz. Microwave frequency filters such as , transversal filtering, correlation, and variable delay line could be accomplished by the CCDs based on this technology. These filters would find many uses in microwave frequency applications such as personal mobile communication devices and in the communication systems (1)-(5). In this work, charge transfer process of a 2DEG-CCD by ensemble Monte Carlo method is simulated. In the simulation we used a simplified structure that reported in (6) with difference that a cermet film is used to encapsulate the inter-electrode gaps. The cermet film results in a monotonic variation of the surface potential between the electrodes at all clock frequencies (7). As a consequence, energy troughs which would otherwise be produced in the active layer under the inter-electrode gaps are removed. This eliminates the possible performance degradation caused by the retention of passing signal charges, thus effectively increasing the charge transfer efficiency (CTE) of the device. This structure also eliminate the need of submicron (<0.5gm) inter-electrode gaps(8). Since the surface potential between the electrodes vary linear calculating the scattering in all mesh point is very complex. Therefore, a simple approximation to this problem is more convenient. Thus we propose a new approach to simulating the charge transfer in the CCD that will be described in the section III. In the following, first, charge transfer is simulated for GaAs channel material system and then effect of choice of material system upon speed of charge transfer is discussed. It was observed that transit speed will be

ENHANCEMENT OF QUALITY OF SERVICE PARAMETERS IN WIMAX MOBILE NETWORKS

Next generation mobile networks are expected to provide seamless personal mobile communication and QoS. Since the demands for high speed Internet access as well as multimedia service had increased for last mile broadband access, the Scheduling is one of the most important components of BWA systems that affect system QoS provided to users. Priority queuing gives better throughput than the existing scheme. The IEEE 802.16 standard is a rapidly developing technology for broadband wireless access system. It supports QoS and has very high transmission rate. WiMAX is a standard wireless technology which is used to improve internet access and the multimedia services at very high speed to the end user. The purpose of QoS is to provide a definitive connection to the users who are intrested to connect to the WiMAX tower. In this study we propose a scheme to improve the QoS in the WiMAX system by increasing the throughput and decreasing the jitter. This study is based on the use of two scheduling algorithms to calculate the data in the MAC layer in order to provide maximum throughput. Moreover we propose a scheme to calculate the jitter between the various mobile users. The scheme performance is investigated through simulation. Priority Queuing gives better throughput compared to the Random Early Detection. Also jitter is minimized in priority queuing.

Streaming media service based on fuzzy similarity in wireless mobile networks

Owing to the recent development in mobile network technologies, users may enjoy streaming media services anytime, anywhere using personal mobile communication devices. Wireless mobile streaming media services, however, have such problems as delay, congestion, and crosstalk due to narrow network bandwidth and limited resources. These problems degrade not only Quality of Service (QoS), but also responsiveness and reliability of the streaming media service. To solve this problem, this paper proposes a Fuzzy Similarity-Based Transcoding Proxy (FSTP) mechanism. The proposed FSTP mechanism analyzes the fuzzy similarity of partitioned segment versions of media objects to construct a Fuzzy Similarity-Based Transcoding Graph (FSTG). The constructed FSTG determines transcoding for the partitioned media object segment versions. The determined transcoding improves Delay Saving Ratios (DSR), Cache Hit Precision Ratio (CHPR), and Cache Hit Recall Ratio (CHRR). Therefore, the more relevant media object segment versions, determined by the fuzzy similarity, are transcoded and cached first to reduce the start delay time and network traffic. The proposed mechanism is simulated to evaluate various performance parameters. The simulation results show that the proposed mechanism achieves improved performance in DSR, CHPR, and CHRR compared with those of other existing mechanisms.

A compact dual-band RF front-end and board design for vehicular platforms

Modern vehicular platforms include several wireless systems that provide navigation, entertainment and road side assistance, among other services. These systems operate at different frequency bands and thus careful system-level design should be followed to minimise the interference between them. In this study, we present a compact dual-band RF front-end module for global positioning system (GPS) operating in the L1-band (1574.42–1576.42 MHz) and satellite digital audio radio system (SDARS) operating in the S-band (2320–2345 MHz). The module provides more than 26 dB of measured gain in both bands and low noise figure values of 0.9 and 1.2 dB in SDARS and GPS bands, respectively. The front-end has interference suppression capability from the advanced mobile phone system and personal communication service cellular bands. The module is designed on a low-cost FR-4 substrate material and occupies a small size of 62 × 29 × 1.3 mm3. It dissipates 235 mW in the SDARS section and 100 mW in the GPS section. Three prototypes have been built to verify a repeatable performance.

DETECTING USER GESTURES WITH A PERSONAL MOBILE COMMUNICATION DEVICE

System and methods for recognizing user gestures by processing audio from a microphone in a personal mobile communication device (PMCD) are disclosed. One such method includes sensing audio using a microphone in the PMCD and detecting a user gesture from audio sensed by the microphone. One such system includes a microphone, memory for storing instructions, and a processor configured by the instructions to sense audio using the microphone and detecting user gestures from audio sensed by the microphone. Also disclosed is a computer-readable medium storing a computer program for use in a personal mobile communication device. The program comprises instructions to: sense audio using a microphone in the personal mobile communication device; record the audio sensed by the microphone; process the recorded audio to extract a feature; classify the feature of the recorded audio; and identify one of a plurality of user gesture types based on the classified feature.

RADIOFREQUENCY AND MICROWAVE RADIATION HEALTH EFFECTS AND OCCUPATIONAL EXPOSURE

In the recent years, there have been considerable discussion and concern about the possible hazards of RF/MW radiation. More recently, the growth and development in personal mobile communications have focused attention on the frequencies associated with this technology. A number of studies have examined the health effects of RF/MW electromagnetic fields (EMFs), originating from occupational exposure, hobbies, or residence near the radio or television transmitters. Particularly controversial are the biophysical mechanisms by which these RF fields may affect biological systems. General health effects reviews explore possible carcinogenic, reproductive and neurological effects. Health effects by exposure source have been observed in radar traffic devices, wireless communications with cellular phones, radio transmission, and magnetic resonance imaging (MRI). Several epidemiological surveys have suggested associations with non-specific complaints such as headache, tiredness, sleep disturbance, loss of memory, and dizziness. These findings, which echo reports of illness associated with other types of radiofrequency (RF) radiation, relate not only to the use of mobile phones, but also to residence near the mobile phone base stations and other settings involving occupational exposure. The biological effects suggest that some precautions are necessary, and preventive approaches are highly recommended. Further researches are required to give more information about the effects of microwave radiation on our health, especially in occupational setting and professionally exposed workers.

FPGA implementation of elliptic curve cryptography engine for personal communication systems

Elliptic Curve Cryptography (ECC), which allows smaller key length as compared to conventional public key cryptosystems, has become a very attractive choice in wireless mobile communication technology and personal communication systems. Any cryptosystem requires a very quick computation in very short time to get an optimal efficiency. One of the options could be to implement the overall cryptosystem into FPGA to reduce the execution time dramatically to pledge the efficiency. In this research, the ECC encryption engine has been implemented in Field Programmable Gate Arrays (FPGA) for two different key sizes, which are 131 bits and 163 bits. The cryptosystem, which has been implemented on Altera’s EPF10K200SBC600-1, has taken 5945 and 6913 logic cells out of 9984 for the key sizes of 131 bits and 163 bits respectively with an operating frequency 43 MHz, and performs point multiplication operation in 11.3 ms and 14.9 ms for 131 bits and 163 bits implementation respectively. In terms of speed, the cryptosystem implemented on FPGA is 8 times faster than the software implementation of the same system. Key words: Encryption, DES, 3DES, FPGA, synthesis, hardware.

AN EFFICIENT PACKET SCHEDULING ALGORITHM FOR 4G IP-BASED MOBILE NETWORKS

Next generation mobile networks are expected to provide seamless personal mobile communication and quality of service (QoS). Lossless handoff is a key issue for providing the QoS. This paper presents 4G node B Architecture, a two-layer downlink queuing model and proposes a scheduling mechanism for providing lossless handoff and QoS in mobile networks, which exploit IP as a transport technology for transferring datagrams between base stations and the high-speed downlink packet access (HSDPA) at the radio layer. In order to reduce handoff packet dropping rate at the radio layer and packet forwarding rate at the IP layer and to provide high system performance, new scheduling algorithms are performed at both IP and radio layer, which exploit handoff priority scheduling principles and take into account buffer occupancy and channel conditions. Performance results obtained by computer simulation show that, by exploiting the downlink queuing model and scheduling algorithms, the system is able to provide low handoff packet dropping rate, low packet forwarding rate, and high downlink throughput.

Green radio: Energy efficiency in wireless networks

Rarely have technical innovations changed everyday life as fast and profoundly as the massive use of personal mobile communications. In the past two decades mobile wireless services grew from niche market applications to globally available components of daily life: The first GSM phone call took place in 1991 in Finland and only 15 years later there were over two billion GSM users. Today there are already more than 4 billion mobile phone subscribers in the world, more than half the population of the planet, and there are expected to be more than 1.2 billion mobile broadband subscribers by 2012. For the first time in history, worldwide mobile data traffic exceeded voice traffic in December 2009, a point which had already been reached in WCDMA networks in 2007.

Topics in integrated circuits for communications [Series Editorial

Over the past several years, mobile personal communication devices have converged to a few popular platforms including the smart phone, personal media player, and personal navigation device. More recently, a miniature laptop known as a netbook has also become increasingly widespread. Common in all these devices is the incorporation of multiple communication functions such as personal navigation, personal area networking, local area networking, wireless personal area networking, TV reception, and mobile cellular networking. Moreover, many of these functions are provided via different communications standards; for example, the Global Positioning System (GPS) for personal navigation, IEEE 802.11a/g/n (otherwise known as Wi-Fi) for wireless local area networking, and Bluetooth and IEEE 802.15.4 (ZigBee) for wireless personal area networking. In the case of TV broadcasting, standards are well established but extremely fragmented. A short list of digital TV broadcast standards includes DVB-H, DVB-T, ISDB-T, T-DMB, CMMB, and MediaFLO. Cellular standards likewise are still fragmented based on GSM/EDGE and WCDMA/UMTS although the cellular industry is working diligently toward a consolidated fourth-generation system based on Third Generation Partnership Project (3GPP) Long Term Evolution (LTE).

Supporting and Enhancing Undergraduate Learning with m-learning tools

New undergraduate students face a variety of challenges associated with making the transition to higher education (HE), including the removal of structures provided by the regulations and syllabus in schools and colleges, and family support. Academic demands, expositive teaching approaches, reduced interaction or personal contact with tutors, and a requirement for independent study can result in a difficult first semester for some students. The latest generation of undergraduates live and have grown up in a highly connected world which, it is claimed, causes them to develop fundamentally different ways of thinking and information processing from their predecessors. For example, today's students are thought of as inhabiting a complex array of communication networks mediated by an evolving ecology of mobile and non-mobile devices. The 'niche' occupied by the mobile phone is of particular interest owing to its prevalence across the student population and the growing functionality that they support.It is claimed that mobile learning (m-learning) opportunities can offer alternative or complementary modes of learning that more closely match these students' preferences Many pilot or demonstrator (proof of concept) m-learning projects have illuminated the potential for mobile devices to support learning and change in HE approaches. Typically these might involve the use of high specification devices running specialist software packages and/or focus on using mobile devices as part of highly student centred learning experiences located remote from more traditional learning contexts. Few studies have explored how to harness existing infrastructures of personal mobile devices or the protocols of social communication for academic purposes. Furthermore, little is known about how mobile mediated communication might compliment more traditional learning and teaching contexts (e.g. lectures, seminars and more recently and increasingly, Virtual Learning Environments (VLEs)). This paper seeks to add knowledge in these areas by reporting and reflecting on a case study which investigates how the academic and personal development of first year students (n=81) on an undergraduate sports education degree can be supported and enhanced by m-learning. Drawing on Moore's theory of transactional distance we aimed to reduced the 'distance' between tutor and students and students and the course content. More specifically, by structuring inter-session study time using group learning activities we sought to establish learning networks that more effectively support the student experience on a core unit of study. In addition, we sought to harness the communication cultures and skills of these 'digital native'students, using mobile phones and SMS. We review findings from a student survey about the extent of mobile phone ownership, the capability of the devices, the range of contracts, and student views about the potential use of their phones as tools for learning. The survey informed the initial design of a set of group learning activities giving structure to out-of-session study while facilitating greater connectivity between the students and their course, and between the students and the tutor. Asynchronous tools (forums and wikis) in the VLE were used in concert with mobile communication, managed through a bulk texting service. We report on the outcomes of our formative and summative evaluations which yielded both qualitative and quantitative data from a variety of sources: focus groups, an online discussion forum, student questionnaire, access statistics from the Moodle VLE and bulktexting service, and the tutor's reflective journal. We discuss our early findings linked to the outcomes of our evaluation, specifically three key issues: how texting can support student time management; how the SMS communication can extend the tutor's voice; and to what extent we were successful in appropriating students' personal mobile communication infrastructures. Finally we discuss how this study addresses some of the challenges associated with the perceived increase in transactional distance caused by physical, cognitive and digital remoteness between students and their teachers.

Personal Digital Assistant‐based, Internet‐enabled Remote Communication System for a Wearable Pneumatic Biventricular Assist Device

Currently, personal mobile communication devices have become quite common, and the applications of such devices have expanded quickly. Remote communication systems might be employed for the telemonitoring of patients or the operating status of their medical devices. In this article, we describe the development of a mobile-based artificial heart telemanagement system for use in a wearable extracorporeal pneumatic biventricular assist device, which is capable of telemonitoring and telecontrolling the operating status of the ventricular assist device from any site. The system developed herein utilized small mobile phones for the client device and adopted a standard transmission control protocol/Internet protocol communication protocol for the purposes of telecommunication. The results of in vitro and animal experiments showed that the telemanagement system developed herein operated in accordance with the desired parameters.

Downlink queuing model and packet scheduling for providing lossless handoff and QoS in AG mobile networks

Next generation mobile networks are expected to provide seamless personal mobile communication and quality-of-service (QoS) guaranteed IP-based multimedia services. Providing seamless communication in mobile networks means that the networks have to be able to provide not only fast but also lossless handoff. This paper presents a two-layer downlink queuing model and a scheduling mechanism for providing lossless handoff and QoS in mobile networks, which exploit IP as a transport technology for transferring datagrams between base stations and the high-speed downlink packet access (HSDPA) at the radio layer. In order to reduce handoff packet dropping rate at the radio layer and packet forwarding rate at the IP layer and provide high system performance, e.g., downlink throughput, scheduling algorithms are performed at both IP and radio layers, which exploit handoff priority scheduling principles and take into account buffer occupancy and channel conditions. Performance results obtained by computer simulation show that, by exploiting the downlink queuing model and scheduling algorithms, the system is able to provide low handoff packet dropping rate, low packet forwarding rate, and high downlink throughput.

The stimulus factors and consumers' relevance treatment of Multimedia Messaging Services

Mobile technology and personal communication have grown significantly over the last few years. As an enhancement from Short Messaging Service (SMS) and Enhanced Messaging Service (EMS), Multimedia Messaging Service (MMS) provides rich content for mobile messaging Person-to-Person (P2P). This paper presents a study aimed at understanding the consumers' relevance treatment towards the usage of MMS and to determine the circumstance by which consumers would accept the usage of MMS. The result of this study also showed that there is a significant difference between the consumers' intention to use MMS in the Asia and Oceania regions.

Adaptive coding and modulation scheme for satellite-UMTS TDD systems based on a photogrammetric channel estimation method

The conventional wireless communication systems are designed to overcome the worst-case channel, using the huge amount of redundant bits to assure communications performance and quality of services. Those systems cannot achieve the optimum spectrum and power efficiency. This paper presents an adaptive coding and modulation scheme used in the user terminals of the third-generation satellite communication system. A three-state photogrammetric channel estimation method is introduced for tracing the variations of large-scale environments. The mobile user terminal dynamically switches the suitable coding and modulation schemes according to the result of photogrammetric channel estimator in order to maximize the power efficiency and data throughput. The real measurement data were used to validate our proposed method. The results show that the proposed method not only reduces the system complexity, but also mitigates the power control requirements and increases the data throughput for the land mobile satellite personal communication systems. Copyright © 2006 John Wiley & Sons, Ltd.

Mobile communications - an overview

This article focuses on voice communications using mobile (cell) phones over mobile/cellular networks. The advances in processors, memory, signal processing, communication technologies, and several related techniques, personal mobile communications has witnessed tremendous growth. A typical mobile communication network consists of: mobile devices, BS, mobile switching centers, gateway mobile switching center. Cell phones communicate wirelessly with BSs. Base stations communicate with MSCs on fiber-optic cables or microwave links. Some of the extensions are also made in the cell phone, MMS, JPEG format, MPEG format, graphics, and animation.