Showing papers on "GSM published in 1999"

Mobile Radio Communications

Abstract: From the Publisher: Mobile radio communications technology has progressed rapidly and it is now capable of the transmission of voice, data and image signals. This new edition explains the latest techniques employed in second and third generation systems. A comprehensive all-in-one mobile communication reference work, Mobile Radio Communications, Second Edition reflects the current state-of-the-art by featuring expanded and updated sections on voice compression techniques, interleaving and channel coding methods, quaternary frequency shift keying, continuous phase modulation methods, Viterbi equalisation and slow frequency hopping as well as extended coverage of the GSM system; and three new chapters on wireless multimedia, third generation systems and on WATM respectively. As in the first edition, this edition continues to cover important topics such as radio propagation, multiple access methods and, on a higher level, cordless telecommunications and teletraffic issues. This book will prove invaluable to mobile communication engineers, designers, researchers and students in the design, operation and research of second and third generation systems and wireless LANs.

EDGE: enhanced data rates for GSM and TDMA/136 evolution

Abstract: Two of the major second-generation standards, GSM and TDMA/136, have built the foundation to offer a common global radio access for data services. Through use of a common physical layer, EDGE, both standards will have the same evolutionary path toward providing third-generation services. EDGE is currently subject to standardization in TIA TR45.3 and ETSI SMG, a process which will be finalized at the end of 1999. Compared to the existing data services in GSM and TDMA/136, EDGE will provide significantly higher user bit rates and spectral efficiency. EDGE can be introduced in these systems in a smooth way, using existing frequency plans of already deployed networks. This article gives the rationale behind the development of the EDGE concept, presents the EDGE technology, and addresses performance by means of system simulations.

GSM phase 2+ general packet radio service GPRS: Architecture, protocols, and air interface

Abstract: The general packet radio service (GPRS) is a new bearer service for GSM that greatly improves and simplifies wireless access to packet data networks, e.g., to the Internet. It applies a packet radio principle to transfer user data packets in an efficient way between mobile stations and external packet data networks. This tutorial gives an introduction to GPRS. The article discusses the system architecture and its basic functionality. It explains the offered services, the session and mobility management, the routing, the GPRS air interface including channel coding, and the GPRS protocol architecture. Finally, an interworking example between GPRS and IP networks is shown.

Location tracking of mobiles in cellular radio networks

Abstract: Some useful services in cellular radio networks and also a class of handover algorithms require knowledge of the present position and velocity of mobiles. This paper deals with a method to track mobiles by on-line monitoring of field strength data of surrounding base stations at successive time points. Such data is available in present global system for mobile communication (GSM) systems each 0.48 s and also in code-division multiple-access (CDMA) systems for transmission control. Because of strong random fluctuations of the signals, appropriate smoothing is the key point of the procedure. We develop a locally linear prediction model of successive positions as a basis for Kalman filtering. This approach turns out to be extremely successful, achieving average mislocations of 70 m in simulated test runs. Further improvement is possible by using external geographical information.

RF architecture for cellular dual-band telephones

Abstract: A dual band RF architecture including a GSM quadrature modulator for modulating an intermediate frequency (IF) wherein the frequency of the modulated IF signal is changed such that one IF is used for the GSM band and another IF is used for the DCS 1800 band. An intermediate frequency (IF) filter with a pass band that covers both the GSM IF and the DCS 1800 IF is connected to the output of the modulator and outputs to a transmit phase lock loop, which translates the IF signal from the IF filter to either a DCS 1800 band radio frequency signal or a GSM band radio frequency signal, depending on the frequency of a local oscillator (LO). The receiver employs a down converter which provides a down converted output signal selected by high side injection for the GSM band an by low side injection for the DCS 1800 band. The down converter outputs to an intermediate frequency (IF) receiver filter centered at 400 MHz designed to pass either the down converted GSM signal or the down converted DCS signal to demodulation circuitry. A single phase lock loop circuit is used to supply, on a single output, the LO signal for down converting either the GSM receive band or the DCS 1800 receive band, as well as the LO for the transmit phase lock loop.

Error-Control Coding for Data Networks

Abstract: From the Publisher: This book takes a structured approach to channel-coding, starting with the basic coding concepts and working gradually towards the most sophisticated coding systems. The most popular applications are described throughout the book. These applications include the channel-coding techniques used in mobile communication systems such as: the global system for mobile communications (GSM) and the code-division multiple-access (CDMA) systems, coding schemes for High-Definition TeleVison (HDTV) systems, the Compact Disk (CD), and Digital Video Disk (DVD), as well as the error-control protocols for the datalink layers of networks, and much more.

System and method for informing network of terminal-based positioning method capabilities

Abstract: A telecommunications system and method is disclosed for allowing a cellular network to determine the optimum positioning method, having knowledge of all available network-based and terminal-based positioning methods. This can be accomplished by the Mobile Station (MS) sending to the Mobile Switching Center/Visitor Location Register (MSC/VLR) a list of terminal-based positioning methods that the MS is capable of performing. This list can, in turn, be forwarded to the Mobile Positioning Center (MPC) for determination of the optimum positioning method. For example, in a GSM network, the MS CLASSMARK information, which is sent to the MSC/VLR when the MS registers with the MSC/VLR, can be extended to include the MS's positioning capabilities.

Mobile Radio Communications: Second and Third Generation Cellular and WATM Systems: 2nd

Abstract: This comprehensive all-in-one reference work covers the fundamental physical aspects of mobile communications and explains the latest techniques employed in second and third generation digital cellular mobile radio systems. Mobile radio communications technology has progressed rapidly and it is now capable of the transmission of voice, data and image signals. This new edition reflects the current state-of-the-art by featuring: * Expanded and updated sections on voice compression techniques, interleaving and channel coding methods, quaternary frequency shift keying, continuous phase modulation methods, Viterbi equalisation and slow frequency hopping as well as extended coverage of the GSM system. * Three new chapters on wireless multimedia, third generation systems and on WATM respectively As in the first edition, this latest volume continues to cover important topics such as radio propagation, multiple access methods and, on a higher level, cordless telecommunications and teletraffic issues. This book will prove invaluable to mobile communication engineers, designers, researchers, and students in the design, operation and research of second and third generation systems and wireless LANs.

System and method for interoperable multiple-standard modulation and code selectable Feher's GMSK, enhanced GSM, CSMA, TDMA, OFDM, and third-generation CDMA, W-CDMA and B-CDMA

Abstract: Combined Digital-Analog Signal Processors, Waveforms with Time Constrained Signal (TCS) response and Long Response (LR) filtered Bit Rate Agile (BRA) Modulation-Demodulation (Modem) Format Selectable (MFS) and Code Selectable (CS) system implementations for Interoperable Multiple Standard Enhanced GSM, CSMA, TDMA, OFDM, and third-generation CDMA, W-CDMA and B-CDMA systems and associated methods Systems include Feher's Gaussian Minimum Shift Keying (GMSK or FGMSK) and Feher's Quadrature Phase Shift Keying (FQPSK) systems combined with Adaptive Antenna Arrays (AAA), Pseudo-Error (PE) based Non-Redundant Error Detection (NRED) controlled IF adaptive equalizers, smart antenna and smart diversity systems which have spectral/RF power efficiency and enhanced end-to-end performance

Short message service with improved utilization of available bandwidth

Abstract: Techniques that enable wireless client devices to more efficiently utilize available transmission bandwidth in a wireless network are disclosed. In one embodiment, the techniques operates to include or incorporate return information (data) in an acknowledgement message after an incoming message has been successfully received from a sender. As a result, messages are able to be effectively sent over the wireless network with less overhead. The techniques are particularly suitable for a Global System for Mobile Communications (GSM) network that is capable of bi-directional communications with a short message service center (SMSC).

TCP performance over GPRS

Abstract: GPRS is the new packet-oriented data service for GSM. Soon it will be possible to take advantage of the features provided by GPRS for Internet access like fast connection set-up, volume-based charging and staying on-line for long periods. For non-real-time Internet applications TCP is the applied transport protocol. Often it was suspected that GPRS introduces severe performance degradations for TCP traffic since both apply their own ARQ mechanism. It is well known that layered protocol interactions can have very negative influences. This paper examines with simulations the performance of TCP over GPRS. The behaviour of the protocols is analysed under various conditions. It is shown that both TCP and GPRS are well harmonised.

An efficient IF architecture for dual-mode GSM/W-CDMA receiver of a software radio

Abstract: Software radios have been widely studied as a solution to support multiple air interface standards in future wireless communications. In this paper, we present an efficient IF processing architecture for a dual-mode GSM/W-CDMA terminal based on the concept of software radio. Simplified digital mixer, high decimation rate filter and fractional frequency conversion techniques are adopted in this architecture to make it compatible with both GSM and W-CDMA. Simulation results show the performance of the architecture is suitable.

Apparatus and methods for imaging written information with a mobile telephone set

Abstract: The systems and methods described herein provide communication systems that allow for the transmission of voice and data over a wireless network. To that end, the systems described herein include a mobile wireless communication system, such as a GSM telephone, and a pen input device capable of collecting information about an image written on a writing surface and capable of transmitting that information into the wireless communication device.

Developing Adaptive Applications: The MOST Experience

Abstract: Future computer environments will include mobile computers which will either be disconnected, weakly inter-connected by low speed wireless networks such as GSM, or fully inter-connected by high speed networks ranging from Ethernet to ATM. Such environments place unique demands on systems, requiring software to dynamically adapt to rapid and significant uctuations in communications quality-of-service (QoS). This paper reviews existing adaptation techniques and describes an experiment in developing an adaptive mobile application and associated distributed systems platform. The experiences gained during this experiment are presented and analysed to provide a basis for the engineering of future adaptive systems.

Medium access control layer for packetized wireless systems

Abstract: An arrangement where, in addition to the control channels that are used to set up sessions, there is a logically and physically separate and independent set of control channels that can be used as session control channels. Illustratively, the physical GSM frame arrangement that employs 8 logical slots is used, with one slot both in the uplink and downlink dedicated to these separate control channels. In the downlink, such a control channel provides channel grant information, requests to make and transmit power measurements, poll mobile units, etc. In the uplink, such a control channel can be used to request access to a traffic channel, to report on power measurements, to request special hand-off handling, to respond to polling, etc. Because the uplink session control channel does not need to carry a significant amount of information, the GSM slot can be divided into minislots, with each minislot constituting a session control channel for a group of mobile units.

Enhanced privacy and authentication for the global system for mobile communications

Abstract: The Global System for Mobile Communications (GSM) is widely recognized as the modern digital mobile network architecture. Increasing market demands point toward the relevancy of security-related issues in communications. The security requirements of mobile communications for the mobile users include: (1) the authentication of the mobile user and Visitor Location Register/Home Location Register; (2) the data confidentiality between mobile station and Visitor Location Register, and the data confidentiality between Visitor Location Register and Visitor Location Register/Home Location Register (VLR/HLR); (3) the location privacy of mobile user. However, GSM does not provide enough security functions to meet these requirements. We propose three improved methods to enhance the security, to reduce the storage space, to eliminate the sensitive information stored in VLR, and consequently to improve the performance of the system. Proposed methods include an improved authentication protocol for the mobile station, a data confidentiality protocol, and a location privacy protocol. The merit of the proposed methods is to improve but not to alter the existing architecture of the system. Furthermore, this study also performs computational and capacity analyses to evaluate the original GSM system and proposed approaches on a comparative basis.

Advanced wcdma radio network simulator

Abstract: If only good coverage is required in GSM networks, high frequency reuse factors can be used. In that case the network capacity is directly determined by the number of available time slots, and no advanced radio control algorithms are needed. If high capacity is required and fractional loading is used in GSM networks, advanced radio resource management algorithms are required. Sophisticated network simulators are needed for algorithm development in GSM base station systems. Also, finding out the capacity for accurate network planning is difficult without radio network simulators. In UMTS the need for an advanced radio network simulator will further increase because of new services, higher bit rates, multiplexing of services, and because of the possible asymmetric capacity requirement between uplink and downlink. Additionally, the UTRA WCDMA air interface is more dynamic than the GSM air interface, and therefore, optimised radio resource management algorithms need to be developed to fully exploit the WCDMA capabilities. The algorithm development for highly loaded dynamic networks is not possible without accurate modelling in computer simulations. In this paper the modelling principles of a WCDMA radio network simulator are presented.

Harmonic suppression in dual band mobile phones

Abstract: To effectively suppress harmonics in a dual band mobile phone with a power amplifier (10) outputting transmitting signals for different frequency bands (GSM; PCS, DCS) via a single output as described a power amplifier output circuit in which harmonics are filtered through impedance transformation of a turn-off impedance of a transmitter/receiver change over unit (36, 38). Hereby the desired filtering of harmonics may be achieved without almost no additional expenditure.

The adaptive multi-rate speech coder

Abstract: In this paper, we describe the adaptive multi-rate (AMR) speech coder currently under standardization for GSM systems as part of the AMR speech service. The coder is a multi-rate ACELP coder with 8 modes operating at bit-rates from 12.2 kbit/s down to 4.75 kbit/s. The coder modes are integrated in a common structure where the bit-rate scalability is realized mainly by altering the quantization schemes for the different parameters. The coder provides seamless switching on 20 ms frame boundaries. The quality when used on GSM channels is significantly higher than for existing services.

An adaptive radio link protocol with enhanced data rates for GSM evolution

Abstract: In this article we address the problem of link adaptation in a wireless data system. Link adaptation is necessary in order to match the data rate to time-varying channel and interference conditions. We present a robust radio link protocol (RLP) based on the concept of incremental redundancy (IR). Here, redundant data, for the purpose of error correction, is transmitted only when previously transmitted packets of information are received and acknowledged to be in error. The redundant packet is combined with the previously received (errored) information packets in order to facilitate error correction decoding. If there is a decoding failure, more redundancy is transmitted. It is shown here that an RLP built using the IR concept is more robust and has better throughput than link adaptation schemes using explicit channel measurements such as instantaneous or average signal-to-noise or signal-to-interference ratio. We study the performance of an implementation of a IR-based RLP for EDGE (enhanced data services for GSM evolution) data and demonstrate its superior throughput and robustness properties. The penalty paid for increased robustness and higher throughput is additional receiver memory and higher delay. IR based RLP has already been standardized for IS-136+ packet data and is being actively considered for EDGE standardization.

Mobile internet access

Abstract: A method of enabling roaming of a mobile internet-access host (9) from a local area network (3) to a GSM network (6), each network having a home agent (HA) for routing internet datagrams between networks. The method comprises deregistering the mobile terminal (9) from said local area network (3) and registering it with the GSM network (6) and allocating to the mobile host (9) a new internet address in the GSM network (6). An internet security key is sent via the GSM Short Message Service from the local area network's home agent (HA) to the mobile terminal (9). The new internet address is transmitted, together with authentication data generated using the security key, via the internet (5) to the local area network's home agent (HA) which registers that address as a care-of-address for the mobile host (9).

Principles and applications of GSM

Abstract: From the Publisher: GSM and its derivatives have become the world's #1 wireless technology, enabling users to roam across most of Europe, the Middle East, North Africa, East Asia, and even much of the U.S. - all with one number and one bill. Principles & Applications of GSM is the first complete technical guide to this remarkable technology. Vijay K. Garg and Joseph E. Wilkes begin by introducing basic principles that apply to any wireless technology. Next, they present GSM in depth, covering everything you need to know to design and implement a GSM system.

Multimedia messaging service for GPRS and UMTS

Abstract: Mobile telecommunications networks will evolve to a great extent in the future. They will offer higher data rates and provide new services for nomadic users. The development of packet switched data bearers for 3/sup rd/ generation wireless networks will enable support for multimedia applications as well. Multimedia can be divided into real-time and non-real-time services. In this paper we concentrate on a new non-real-time multimedia service called multimedia messaging service (MMS). Multimedia messaging service allows mobile subscribers to exchange arbitrary types of information in a store-and-forward manner. Multimedia messages may consist of text, images, audio or video clips, or any combination of these. A new network element called multimedia messaging service center is needed for storing and forwarding the messages. We describe in more detail what we mean by multimedia messaging service. We also analyze the different architectural options for supporting multimedia messaging within UMTS (Universal Mobile Telecommunications System) and GPRS (General Packet Radio Service for GSM) networks.

Secure communication mechanisms for GSM networks

Abstract: With the advance of wireless communications technology, mobile communications has become more convenient than ever. However, because of the openness of wireless communications, the protection of the privacy between communicating parties is becoming a very important issue. We focus on the security of the Global System for Mobile communication (GSM) networks. A secure communication architecture for the GSM network is proposed. In the proposed architecture, we use public-key cryptography for user authentication and stream cipher for message encryption and decryption. An authentication protocol and a key generation method are presented in conjunction with the proposed architecture. Cryptanalysis and operational analysis show that the authentication protocol is secure and efficient. Simulation results indicate that the key generation method can always produce key strings of evenly distributed 0s and 1s and with infinite period.

Remote monitoring system using the GSM network

Abstract: The remote monitoring system comprises a signal emitter (10) providing a signal, means for detecting the signal (12), means for transmitting the signal (16) via a global specification for mobile telephones (GSM) network, and remote means (18, 20) for receiving for the transmitted signal. The signal emitter may be a PIR or other intruder or fire sensor. Alternatively, the signal emitter may be a meter reading module, eg using a radio camera, which transmits the meter reading to a remote station. In another arrangement the GSM network may be used to transmit a control signal, eg to the heating system of a building.

Method for positioning gsm mobile stations

Abstract: The present invention provides a method for positioning GSM mobile stations. Positioning information for a Mobile Station (102) is requested by a Base Station Subsystem (117) from Location Determination Equipment (113). The location Determination Equipment (113) return signal measurements relating to the Mobile Station (102) to the Base Station Subsystem (117). The Base Station Subsystem (117) requests a location calculation from a Mobile Positioning Register (111). The Mobile Positioning Register (111) computes the position of the mobile station (102) based at least in part upon the signal measurements. The position of the Mobile Station (102) is then returned to the Base Station Subsystem (117).

A Generalized Space Mapping Tableau Approach to Device Modeling

Abstract: A novel, comprehensive framework to engineering device modeling called Generalized Space Mapping (GSM) is introduced The accuracy of available empirical models of microwave devices can be significantly enhanced by exploiting GSM We present three fundamental illustrations: a basic Space Mapping Super Model (SMSM), a basic Frequency-Space Mapping Super Model (FSMSM) and Multiple Space Mapping (MSM) The new concept is verified on several device modeling problems, typically utilizing very few full-wave EM simulations, yielding remarkable improvement in accuracy

Signalling method and conversion device for telecommunications networks

Abstract: A signalling method and conversion device for telecommunications networks, for example mobile networks such as GSM or UMTS networks, wherein at least certain subscribers can register in their home network, or in a telecommunications network having a roaming agreement with the operator of their home network, using a first subscriber identification from the number area of their home operator, certain of these subscribers being assigned a second subscriber identification from the number area of a partner network operator with which these subscribers can register in a visited network with which operator their home network operator does not have a roaming agreement, the signalling traffic concerning subscribers who have been registered in such a visited network with a second subscriber identification number being conducted to the partner network, being filtered there, and being rerouted to their home network, and signalling traffic concerning such subscribers received in said partner network from said home network being rerouted to this said visited network.

Method and a device for use in a virtual environment

Abstract: Information about avatar characteristics for a user are stored in a removable memory card ( 115 ), for example in a SIM card for the GSM system. The information regarding the avatar can then be moved from one access terminal to another. A virtual world, which the avatar is designed to enter, can then be accessed from many different access terminals by means of inserting the SIM card and entering a personal identity number (PIN) code. Thus by adding such a memory function to a removable memory card (e.g. a SIM card or a Smart card), besides of making it possible to access a virtual world from different access terminals, also makes it possible to use avatars in new applications, such as in a GSM phone or another mobile phone or terminal.

System performance evaluation of mobile positioning methods

Abstract: This paper presents a simulation methodology for evaluating the performance of location techniques for cellular systems. The simulation tool developed enables quantification of the final system performance for various choices of components such as measurement techniques, channel models and position computation methods. Positioning performance of a GSM and IS-136 cellular system is shown for a specific choice of measurements and algorithms in various radio environments. The variation in performance with the choices of system parameters such as number of measurements made per position computation is shown.