Showing papers on "UMTS frequency bands published in 2009"

LTE for UMTS - OFDMA and SC-FDMA Based Radio Access

Abstract: From the editors of the highly successful WCDMA for UMTS, this new book gives a complete and up-to-date overview of Long Term Evolution (LTE) in a systematic and clear manner. It starts with an in-depth explanation of the background and standardization process before moving on to examine the system architecture evolution (SAE). The basics of air interface modulation choices are introduced and key subjects such as 3GPP LTE physical layer and protocol solutions are described. Mobility aspects and radio resource management together with radio and end-to-end performance are assessed. The voice solution and voice capacity in LTE are also illustrated. Finally, the main differences between LTE TDD and FDD modes are examined and HSPA evolution in 3GPP Releases 7 and 8 is described. LTE for UMTS is one of the first books to provide a comprehensive guide to the standards and technologies of LTE. Key features of the book include: Covers all the key aspects of LTE in a systematic manner Presents full description of 3GPP Release 8 LTE Examines the expected performance of LTE Written by experts actively involved in the 3GPP standards and product development.

Interference management and performance analysis of UMTS/HSPA+ femtocells

Abstract: Femtocells are low-power cellular base stations that operate in licensed spectrum. They are typically deployed indoors to improve coverage and provide excellent user experience, including high data rates. Cellular operators benefit from reduced infrastructure and operational expenses for capacity upgrades and coverage improvements. Femtocells also bring unique challenges, such as unplanned deployment, user installation, restricted access, and interoperability with existing handsets and network infrastructure. Although femtocells may cause some interference to other users in the network, with the use of proper interference management techniques, this can be well controlled. We present interference management techniques for both downlink and uplink of femtocells operating based on 3GPP Release 7 standards (also known as HSPA+). Femtocell carrier selection and femtocell DL Tx power self-calibration are proposed as key interference management methods for downlink. For uplink interference management, adaptive attenuation at the femtocell and limiting the Tx power of the femtocell users are proposed. Different interference models and their analysis are presented. In addition, coverage performance and capacity results are presented to quantify the benefits of femtocells. We demonstrate that in addition to coverage enhancements, significant capacity improvements are achieved on both downlink and uplink when femtocells are deployed in 3G UMTS/HSPA+ networks.

Femtocell access control strategy in UMTS and LTE

Abstract: Femtocells have become an attractive device for operators to offer extended services on their licensed UMTS/LTE spectrum. In this article we focus on the access control strategy - a crucial aspect for operators to give preferential access to femtocells for their subscribers. The general issue of supporting femtocells in pre-Release 8 UMTS networks with pre-Release 8 UE is first outlined in order to help the reader understand the motivation behind some concepts introduced in 3GPP Release 8 to support femtocells. A description of the femtocell access control strategy for UMTS and LTE is then provided based on 3GPP Release 8 specifications. Finally, the issue of LTE physical cell identity confusion associated with inbound handover to femtocells (which is expected to be resolved within the 3GPP Release 9 timeline) is discussed.

Standardization of femtocells in 3GPP2

Abstract: Cellular system operators have identified the critical need for standardization of femtocell devices and their associated interfaces into the operators' core networks as a critical requirement for the success of femtocell products Driven by this demand, the UMTS/UTRAN standards community has been undertaking a large-scale and comprehensive effort to specify such standards for femtocell devices and systems that are based on the UMTS/HSDPA/HSUPA family of radio access technologies This article describes those standardization activities and provides an overview for the femtocell system architecture that has been developed within 3GPP

Position Location Techniques and Applications

Abstract: This book is the definitive guide to the techniques and applications of position location, covering both terrestrial and satellite systems. It gives all the techniques, theoretical models and algorithms that an engineer needs to improve their current location schemes and to develop future location algorithms and systems. Comprehensive coverage is given to system design trade-offs, complexity issues, and the design of efficient positioning algorithms, enabling the creation of high-performance location positioning systems. Traditional methods are also re-examined in the context of the challenges posed by reconfigurable and multi-hop networks. Applications discussed include wireless networks (WiFi, ZigBee, UMTS and DVB networks), cognitive radio and sensor and multi-hop networks. . Contains a complete guide to models, techniques and applications of position location. Includes applications to wireless networks (WiFi, ZigBee, DVB networks), cognitive radio, sensor networks and reconfigurable and multi-hop networks, demonstrating the relevance of location positioning to these 'hot' areas in research and development. Covers system design trade-offs, and the design of efficient positioning algorithms enables the creation of future location positioning systems. Provides a theoretical underpinning for understanding current position location algorithms, giving researchers a foundation to develop future algorithms

Digital cellular telecommunications system (Phase 2+); Universal Mobile Telecommunications System (UMTS); LTE;

Abstract: The present document may be made available in more than one electronic version or in print. In any case of existing or perceived difference in contents between such versions, the reference version is the Portable Document Format (PDF). In case of dispute, the reference shall be the printing on ETSI printers of the PDF version kept on a specific network drive within ETSI Secretariat. No part may be reproduced except as authorized by written permission. The copyright and the foregoing restriction extend to reproduction in all media.

Content caching in the radio access network (ran)

Abstract: A system and method to intercept traffic at standard interface points as defined by Cellular/Wireless networks (GSM/GPRS, 3G/UMTS/HSDPA/HSUPA, CDMA, WIMAX, LTE), emulate the respective protocols on either side of the interception point, extract user/application payloads within the intercepted packets, perform optimizations, and re-encapsulate with the same protocol, and deliver the content transparently is disclosed. The optimizations include but are not limited to Content Caching, prediction & pre-fetching of frequently used content, performance of content-aware transport optimizations (TCP, UDP, RTP etc.) for reducing back-haul bandwidth, and improvement of user experience. An additional embodiment of the current invention includes injecting opportunistic content (location based, profile based or advertisement content) based on the information derived while monitoring control plane protocols.

A rhombic patch monopole antenna with modified minkowski fractal geometry for umts, wlan, and mobile wimax application

Abstract: This paper presents a rhombic patch monopole antenna applied with a technique of fractal geometry. The antenna has multiband operation in which the generator model, which is an initial model to create a fractal rhombic patch monopole, is inserted at each center side of a rhombic patch monopole antenna. Especially, a modified ground plane has been employed to improve input impedance bandwidth and high frequency radiation performance. The proposed antenna is designed and implemented to effectively support personal communication system (PCS 1.85–1.99 GHz), universal mobile telecommunication system (UMTS 1.92–2.17GHz), wireless local area network (WLAN), which usually operate in the 2.4 GHz (2.4–2.484 GHz) and 5.2/5.8 GHz (5.15–5.35 GHz/5.725–5.825GHz) bands, mobile worldwide interoperability for microwave access (Mobile WiMAX), and WiMAX, which operate in the 2.3/2.5 GHz (2.305– 2.360 GHz/2.5–2.69 GHz) and 5.5 GHz (5.25–5.85 GHz) bands. The radiation patterns of the proposed antennas are similar to an omnidirectional radiation pattern. The properties of the antenna such as return losses, radiation patterns and gain are determined via numerical simulation and measurement. Corresponding author: C. Mahatthanajatuphat (cmp@kmutnb.ac.th). 58 Mahatthanajatuphat et al.

Energy-efficient management of UMTS access networks

Abstract: The increasing concern about the energy consumption of telecommunication networks is driving operators to manage their equipments so as to optimize energy utilization without sacrificing the user experience. In this paper, we focus on UMTS access networks, since access devices are the main energy consumers in UMTS networks. We propose a novel approach for the energy-aware management of UMTS access networks, consisting in a dynamic network planning, that, based on the instantaneous traffic intensity, reduces the number of active access devices when they are underutilized (typically at night). When some access devices are switched off, radio coverage and service provisioning are taken care of by the devices that remain active, possibly with some small increase in the emitted power, so as to guarantee that service is available over the whole area, with the desired quality.

Gsm and umts : the creation of global mobile communication

Abstract: From the Publisher: GSM (Global System for Mobile communication) provides a service to more than 500 million users throughout 168 countries worldwide. It is the world market leader serving 69 % of all mobile digital users and is currently evolving into UMTS (Universal Mobile Telecommunication System). By describing the critical decisions and the phases of the development this key text explains how the GSM initiative became a success in Europe and how it evolved to the global mobile communication system. Initially the strategy and technical specifications were agreed for Europe and the subsequent evolution to a global solution was achieved by incorporating all non-European requirements and by inviting all committed parties worldwide to participate. The process started in 1982 and the first GSM networks went into commercial service in 1992. The first UMTS networks are expected in 2002 and the fourth generation discussions have begun. *Presents a complete technical history of the development of GSM and the early evolution to UMTS *Clarifies the creation of the initial GSM second generation system in CEPT GSM, the evolution to a generation 2.5 system in ETSI SMG and the evolution to the Third Generation (UMTS) in ETSI SMG and 3GPP *Covers all of the services and system features together with the working methods and organisational aspects GSM and UMTS provides an interesting and informative read and will appeal to everyone involved in the mobile communications market needing to know how GSM and UMTS technologies evolved. The accompanying CD-ROM provides nearly 500 reference documents including reports of all standardisation plenary meetings, strategy documents, keydecisions, the GSM Memorandum of Understanding and the report of the UMTS Task Force.

Handover between macrocell and femtocell for UMTS based networks

Abstract: The femtocell networks that use home base station and existing xDSL or other cable line as backhaul connectivity can fulfill the upcoming demand of high data rate for wireless communication system as well as can extend the coverage area. Hence the modified handover procedure for existing networks is needed to support the macrocell/femtocell integrated network. Some modifications of existing network and protocol architecture for the integration of femtocell networks with the existing UMTS based macrocell networks are essential. These modifications change the signal flow for handover procedures due to different 2-tier cell (macrocell and femtocell) environment. The measurement of signal-to-interference ratio parameter should be considered for handover between macrocell and femtocell. A frequent and unnecessary handover is another problem for hierarchical network environment that must be optimized to improve the performance of macrocell/femtocell integrated network. In this paper, firstly we propose the concentrator based and without concentrator based femtocell network architecture. Then we present the signal flow with appropriate parameters for the handover between 3GPP UMTS based macrocell and femtocell networks. A scheme for unnecessary handoff minimization is also presented in this paper. We simulate the proposed handover optimization scheme to validate the performance.

Compact PIFA for Mobile Terminals Supporting Multiple Cellular and Non-Cellular Standards

Abstract: A novel multiband planar inverted-F antenna (PIFA) covering ten frequency bands has been proposed for personal wireless communications terminals. The design is based on the combination of various techniques that are used for designing multiband/broadband antennas. We used a shorted parasitic patch efficiently coupled to the driven patch, a quarter-wave resonator connected to the feed strip in parallel with the main patch, and four slits in the main radiator to excite various current modes in the antenna structure. The antenna is designed within a volume of 4.0 times 2.0 times 0.8 cm3 and it can be used to serve the following wireless communication systems: Global System for Mobile Communications (GSM-900), Digital Communications System (DCS), Personal Communication Service (PCS), Universal Mobile Telecommunications System (UMTS), WiBro at 2.35 GHz, Bluetooth, Satellite-Digital Multimedia Broadcasting (SDM-B) at 2.65 GHz, WiMAX at 3.5 GHz, and the two bands (5.15-5.35 GHz and 5.725-5.875 GHz) for the wireless Local Area Network (WLAN) standards. A prototype antenna was fabricated and tested for input reflection coefficient and radiation performances. The measured and simulated results have been presented and discussed. Important geometrical parameters determining the multiband performances of the antenna have been explained in the paper.

Handover location accuracy for travel time estimation in GSM and UMTS

Abstract: Field measurements from the GSM and UMTS networks are analysed in a road traffic information context. The measurements indicate a potentially large improvement using UMTS signalling data compared with GSM regarding handover location accuracy. These improvements can be used to generate real-time traffic information with higher quality and extend the geographic usage area for cellular-based travel time estimation systems. The results confirm previous reports indicating that the technology has a large potential in GSM and also show that the potential might be even larger and more flexible using UMTS. Assuming that non-vehicle terminals can be filtered out, that vehicles are tracked to the correct route and that handovers can be predicted correctly, a conclusion from the experiments is that the handover location accuracy in both GSM and UMTS will be sufficient to estimate useful travel times, also in urban environments. In a real system, these tasks are typically very challenging, especially in an urban environment. Further, it is reasonably established that the location error will be minor for the data obtained from UMTS.

Energy-aware network selection using traffic estimation

Abstract: This paper proposes an energy-aware handoff algorithm based on energy consumption measurements of UMTS and 802.11 WLAN networks on an Android mobile phone. The handoff algorithm uses estimation of application traffic size to find the minimum energy cost alternative by comparing the cost of using UMTS with the cost of performing an opportunistic downward vertical handoff to a WLAN and using WLAN for the transfer and the eventual upward vertical handoff back to UMTS. Our experiments show that the energy cost of UMTS is nearly equal to WLAN as a function of transfer time, but for bulk transfers, transferring a byte of data over UMTS can be over a hundred times more expensive than over WLAN. Further, we discovered that the energy cost of the vertical handoff is quite high, comparable to downloading 0.12-0.67 MB of data over UMTS. To calculate the energy cost of data transfers before they take place, we propose and evaluate a distributed traffic estimation mechanism. The mechanism can predict how much data will be transferred due to a user action (i.e. clicking of an URL link). We provide initial results on the accuracy of the mechanism. Finally, we perform a numerical analysis on the the performance of the handoff algorithm and show that it can reduce the energy consumption significantly when compared with simple policies.

Performance and modeling of lte h-arq

Abstract: The 3rd Generation Partnership Project (3GPP)’s Release’8 Long Term Evolution (LTE) defines the next step of 3G technology. LTE offers significant improvements over previous technologies such as UMTS/HSPA. Higher downlink and uplink speeds, lower latency and simpler network architecture are among the new features that are provided. One of the central features that provides transmission robustness is hybridARQ, which in LTE provides physical layer retransmission using incremental redundancy and soft combining. In this paper we propose a low-complexity model based on AWGN link level simulations that is capable of reliably predicting the BLER improvement due to the use of incremental redundancy H-ARQ in LTE.

Deployment options for femtocells and their impact on existing macrocellular networks

Abstract: Femtocells can enable in-home cell phone coverage and provide access to high speed wireless broadband services where the usual macrocell system can only provide degraded service indoors or provide no coverage at all. In this paper, different frequency deployment and access strategies for femtocells are explored, and their impact on the performance of both the femtocells and existing macrocellular networks is investigated. Options such as shared, partially shared, and separate carrier deployments with private and public access are discussed. For shared carrier operation, the impact on the coverage, blocking probabilities, and capacity is investigated based on scenario data from real deployments using the Alcatel-Lucent Ocelot® coverage engine, which includes sophisticated models for various wireless technologies including the Universal Mobile Telecommunications System (UMTS) and high speed downlink packet access (HSDPA). It is shown that co-channel operation of femto- and macrocells is feasible without causing coverage problems due to the increased interference when public access is allowed. For private access, co-channel operation results in dead zones and reduced coverage probability for proximate mobile terminals with no access to those femtocells. This problem can be resolved by using partially shared carriers with a “clean” macrocell carrier for affected mobile devices, or a separate carrier deployment.

Theory and Practice of RRC State Transitions in UMTS Networks

Abstract: GPP has been enhancing UMTS networks by issu- ing new standard releases recurrently. However, the RRC state transition model has remained rather unchanged through sev- eral releases, namely, Rel. 99, Rel. 05 and Rel. 06. We review RRC state transitions and study them in practice using our nov- el 3G Transition Triggering Tool (3G3T), focusing on the net- work configuration parameters that prompt these transitions. We employ 3G3T in a landmark measurement study involving four UMTS networks in three countries and validate our find- ings using a state-of-the art proprietary measurement tool. Our results show that 3G3T is able to discover RRC configuration parameters without operator involvement or cooperation. We observe significant differences in UMTS network configura- tions, which directly impact end-user data service performance. We find that, in practice, the behavior of public UMTS net- works cannot be solely described based on the theoretical con- structs found in the literature, and that tools such as 3G3T are necessary in order to obtain a complete picture. The results pre- sented in this paper aim to assist simulationists in developing better models for UMTS networks. Moreover, we expect that operators can use 3G3T to configure their networks more effi- ciently. Finally, our methods and algorithms should be of great interest to application developers for mobile broadband net- works based on 3GPP standards.

Interworked WiMAX-3G cellular data networks: An architecture for mobility management and performance evaluation

Abstract: This paper proposes an architecture for interworking heterogeneous all-IP networks with an in-depth analysis of its performance. The novelty of this framework is that it freely enables any 3G cellular technology, such as the Universal Mobile Telecommunications System (UMTS) or the CDMA 2000 system, to interwork with a given broadband wireless access (BWA) system, such as the Worldwide interoperability for microwave access (WiMAX) network or the wireless local area network (WLAN) via a common signaling plane. As a universal coupling mediator for real-time session negotiation and management between these dissimilar networks, the IP multimedia subsystem (IMS) has been exploited. The analytical evaluation investigates the behavior of handoff delay, transient packet loss, jitter, and signaling cost during a vertical handoff for the given framework. Finally, an OPNET based simulation platform has been introduced for the verification of the analytical model and results.

Wavelet-Based Compression With ROI Coding Support for Mobile Access to DICOM Images Over Heterogeneous Radio Networks

Abstract: Most of the commercial medical image viewers do not provide scalability in image compression and/or region of interest (ROI) encoding/decoding. Furthermore, these viewers do not take into consideration the special requirements and needs of a heterogeneous radio setting that is constituted by different access technologies [e.g., general packet radio services (GPRS)/ universal mobile telecommunications system (UMTS), wireless local area network (WLAN), and digital video broadcasting (DVB-H)]. This paper discusses a medical application that contains a viewer for digital imaging and communications in medicine (DICOM) images as a core module. The proposed application enables scalable wavelet-based compression, retrieval, and decompression of DICOM medical images and also supports ROI coding/decoding. Furthermore, the presented application is appropriate for use by mobile devices activating in heterogeneous radio settings. In this context, performance issues regarding the usage of the proposed application in the case of a prototype heterogeneous system setup are also discussed.

Filter bank based multi-mode multiple access scheme for wireless uplink

Abstract: This paper investigates the potential of filter bank (FB) processing in the context of uplink multi-user access. First, a FB based scheme, conceptually similar to the single carrier frequency division multiple access (SC-FDMA) developed by 3GPP for uplink in the Long Term Evolution of UMTS, is analyzed. Specifically, a method for synthesizing spectrally well-localized uplink waveforms with low peak-to-average power ratio, using FB based multicarrier (FBMC) modulation in combination with FB spreading, is introduced. Secondly, the superior frequency selectivity of the FB approach, when combined with frequency sampling -designed subchannel/subband processing, is found to enable flexible and bandwidth efficient multi-mode uplink transmission with relaxed constraints on inter-user timing synchronization. The proposed concept allows different mobile terminals to operate in the reverse link simultaneously in multicarrier, SC-FDMA, or conventional single carrier mode according to attributes such as the required transmission power.

Method of transmitting power headroom reporting in wireless communication system

Abstract: Disclosed is related to a method of effectively transmitting a power headroom report (PHR) from the terminal to the base station in an evolved universal mobile telecommunications system (E-UMTS) evolved from universal mobile telecommunications system (UMTS) or a long term evolution (LTE) system, and more particularly, to a method of providing the power headroom report after determinations of whether the power headroom reporting is triggered and whether allocated uplink resource(s) accommodate a medium access control (MAC) control element.

Blocking Probability Calculation for Cellular Systems with WCDMA Radio Interface Servicing PCT1 and PCT2 Multirate Traffic

Abstract: This article proposes a method that can calculate the blocking probability of multi-service cellular systems with Wideband Code Division Multiple Access radio interface The method considers a finite and an infinite source population and takes into account the interdependency of calls service processes in neighboring cells and in both the uplink and the downlink directions The basis of the proposed method is the fixed-point methodology A comparison of the results of analytical calculations to those of simulations confirms the accuracy of the proposed method The proposed scheme can realize cost-effective radio resource management in 3G mobile networks and can be easily applied to network capacity calculations

A New Printed Antenna for Multiband Wireless Applications

Abstract: This study presents a new design of a printed antenna with simply shaped radiator element for multi-operating bands of the wireless communication systems. With a simple design configuration and slot form on a printed circuit board, the proposed antenna can be used in multiband wireless operations, covering the GSM (880-960 MHz), DCS (1710-1880 MHz), PCS (1850-1990 MHz), UMTS (1920-2170 MHz), 2.4-GHz WLAN (2400-2484 MHz), Mobile-WiMAX (IEEE 802.16e in the Taiwan: 2500-2690 MHz) and 5-GHz WLAN (5150-5350/ 5725-5825 MHz) bands. Several properties of the proposed printed antenna in multiband operation, such as impedance bandwidth, radiation pattern and measured gain are numerically and experimentally investigated.

Usability Issues in Mobile-Wireless Information Systems

Abstract: Introduction The evolution of technology in the fields of handheld devices like cellular phones, personal digital assistants (PDA) and smart-phones and in the field of wireless communications increased the development of mobile-wireless information systems, which can be used ubiquitously. Mobile-wireless information systems can create benefits for organizations; such as productivity enhancement, processes and procedures flexibility, customer services improvement and information accuracy for decision makers, which together emphasize competitive strategy, lower operation costs, and improved processes (Lau, 2006; Lee, 2003; Lovell, 1995). But, on the other hand, they face new kinds of problems: narrow bands, small devices, tiny screens and diversity of users and devices. These problems threaten the quality of such systems (Terho, 2002), including the usability quality characteristic, which is one of the characteristics that compose the multi-dimension concept of information systems' quality. Research on quality of information systems has been focused on traditional (Kan, 2002) and internet information systems (Calero, Ruiz, & Piattini, 2004; Covella & Olsina, 2006). The special mobile-wireless information systems characteristics require a different quality definition. In order to define the level of quality of a mobile-wireless information system, there is a need to measure, among others, the usability characteristic. This paper introduces the various definitions of usability and presents new metrics, defined according to Gafni's methodology (2008), to measure the usability of mobile-wireless information systems. The metrics were defined and empirically validated. Mobile-Wireless Information Systems Schiller (2000) describes two mobility dimensions: user mobility which allows connection to the system from different geographical sites and device mobility which enables mobility of both user and system. This research focuses on mobile-wireless information systems, allowing the users to be connected any time at any place, using handheld devices such as PDAs or cellular phones connected via a wireless network. There are two classifications of mobile-wireless applications: horizontal and vertical (Stafford & Gillenson, 2003). Horizontal applications are general, adaptable to a wide range of users and organizations, e.g.: e-mail, browsers, and file transfer applications. Vertical applications are specific to a type of users or organizations, for example: financial applications, such as money transfer, stock exchange and information inquiry; marketing and advertising applications according to the actual user position, i.e., pushing coupons to stores and information about sales nearby; emergency applications to check real-time information from government and medical databases and utility companies applications used by technicians and meter readers. There were unsuccessful attempts to develop mobile-wireless information systems at the beginning of the millennium, since technology, devices and infrastructures were immature (Sult & Lee, 2003). This situation changed during 2003, and analysts agreed that this kind of systems will grow and their market share will expand (Lau, 2006; Lee, 2003). The major reasons are emergence of third generation wireless networks (Universal Mobile Telecommunications System [UMTS], Code division multiple access [CDMA2000 1x] and General Packet Radio Service [GPRS]), their coverage expansion and development of smart mobile devices. There are several advantages of using these systems in the place and time of the event occurrence, in particular, productivity enhancement, resource allocation flexibility, competitive advantages, service improvements and information accuracy (Malladi & Agrawal, 2002). Usability--A Measurable Quality Characteristic Measuring creates a quantitative description which allows behavior comprehension and enables selection of tools and techniques to control and improve processes, products and resources. …

3G/HSPA Performance in Live Networks from the End User Perspective

Abstract: Operators around the world are improving their 3G/UMTS networks by introducing HSPA (High Speed Packet Access) that includes both, enhanced uplink and downlink. The HSPA is expected to finally provide the mobile broadband access that is able to compete with the fixed connections in performance regarding popular applications such as web browsing, VoIP, and video. However, it has remained unclear how well the live networks fulfill the promises of performance. We contribute in filling this void by providing measurements in live 3G/HSPA networks. We compare TCP and UDP goodput performance in basic WCDMA, HSDPA-only, and HSPA. Moreover, one-way delay and jitter measurement results are presented in a stationary as well as in a mobile scenario. The results show that the enhanced network outperforms clearly its predecessor by offering considerably higher data rates, lower delay, and lower jitter. Also, because of the HARQ (Hybrid Automatic Repeat request), there are notably less delay spikes observed with HSPA than with WCDMA. However, the drive tests show that handovers result in high jitter and interruptions to the communications, which causes, e.g., decreased VoIP call quality. The uplink enhancement (HSUPA) improves the TCP performance beyond the HSDPA-only access, but it is still behind that of the fixed connections. In addition, the properties of the channel allocation mechanism still considerably deteriorate the data rates seen by the user. Nevertheless, the HSPA is an enabler for true mobile broadband internet access.

Pareto Optimal Design of Dual-Band Base Station Antenna Arrays Using Multi-Objective Particle Swarm Optimization With Fitness Sharing

Abstract: The design of dual-band base station antennas under constraints for mobile communications is addressed in this paper. Given the antenna geometry, the method of moments (MoM) is used to compute the antenna characteristics. Two distinct multi-objective evolutionary algorithms are applied in order to find the Pareto front of the feasible solutions that satisfy the design constraints. In the present work, the Multi-Objective Particle Swarm Optimization with fitness sharing (MOPSO-fs) is compared with the Nondominated Sorting Genetic Algorithm-II (NSGA-II) in order to optimize the antenna geometry. Two design cases are presented. The first case is a five-element array operating in GSM1800/UMTS frequency bands. The second base station antenna array consists of six elements operating in UMTS/WLAN (2.4 GHz) frequency bands.

Radio Wave Propagation in Arched Cross Section Tunnels - Simulations and Measurements

Abstract: For several years, wireless communication systems have been developed for train to infrastructure communication needs related to railway or mass transit applications. The systems should be able to operate in specific environments, such as tunnels. In this context, specific radio planning tools have to be developed to optimize system deployment. Realistic tunnels geometries are generally of rectangular cross section or arch-shaped. Furthermore, they are mostly curved. In order to calculate electromagnetic wave propagation in such tunnels, specific models have to be developed. Several works have dealt with retransmission of GSM or UMTS. Few theoretical or experimental works have focused on 2.4 GHz or 5.8 GHz bands. In this paper, we propose an approach to model radio wave propagation in these frequency bands in straight arch-shaped tunnels using tessellation in multi-facets. The model is based on a Ray Tracing tool using the image method. The work reported in this paper shows the propagation loss variations according to the shape of tunnels. A parametric study on the facets size to model the cross section is conducted. The influence of tunnel dimensions and signal frequency is examined. Finally, some measurement results in a straight arch-shaped tunnel are presented and analyzed in terms of slow and fast fading.