Charged units. Charge rate. Taxation information including tax rate and type. Discount rate when applicable. Local currency and exchange rates. Details about allocated PDP context. User data volumes. User connection time. This may be needed in case the call or session transfer from the home to the visited network is subject to specific fees.
Reference documents about charging 3GPP technical specifications:. Because of the reduced size, supporting all applications on a single device may be too limiting to the end-user, for the following reasons:. Limited end-user experience caused by the poor audio quality or reduced display size.
Limited storage capability. Limited battery life: supporting all features like radio transmission as well as colour display or headset powering is very consuming. All of this may quickly drain the batteries of a small device. For these reasons, it may be of some interest to dissociate the provision of the service itself and the modem side of the service this modem part relates to the pure data-transmission part of the terminal, including the ability to support high bit rate transmission and seamless mobility over a radio interface.
To answer this need, the standard has defined a flexible architecture for terminal realization. The model, shown in Figure 2. In addition, the UE also integrates the user subscriber module also known as the SIM card , further described into the next section. Evolved UMTS Overview 63 The MT module contains all the functions related to the radio interface and wireless network access and data transmission in general.
Therefore, it supports the following features:. Transmission and reception of data and signalling over the radio interface. Authentication and registration to the UMTS network. Session control. Support of radio mobility functions, such as the handover. The TE is the part the end-user has access to, as it supports all the functions related to user applications and interfaces. It contains the following features:. Control of application-related hardware functions, such as speaker, microphones, video cameras, displays, etc.
Support of user applications and services, such as email client, Web-browsing client, instant-messaging client, etc. The physical interface between the TE and the MT is not defined by the standard. Reference documents about the terminal interfaces 3GPP specifications:. The interest is to limit complexity for both terminal vendors which can then choose which subset of the standard they will implement as well as the degree of performance and network manufacturers which can limit the list of possible terminal implementations and therefore reduce the effort in development and inter-operability testing.
Similarly, the standard defines classes of E-UTRAN terminal, defined by a combination of reception and transmission bandwidth. As a consequence, some user- specific information needs to be stored on the terminal side, such as subscriber identity and security credential, to allow the subscriber to authenticate to the network.
All those terms are often described as equivalent. Strictly speaking, the UICC only refers to the circuit card, its physical components, as well as the set of software and protocol for data exchange with an external device which is common to all UICC cards. In addition, the UICC can support any other kind of application forbanking,ticketing oraccesscontrol,e.
Theavailabilityof a valid UICC card is a pre-requisite for a terminal to register to the network and activate a service. However, thestandard tolerates oneexception:theemergency call. In the emergency situation,the network shall be able to accept calls to emergency numbers such as for North America or in Europe initiated by terminals not containing any UICC or an invalid UICC.
The rest of this section provides some details about the hardware and software side of the UICC. The main reference documents are:. However, the introduction of high-speed smart-card alternative technologies — like the MMC Multimedia Card or the SD Secure Digital card — able to cope with high-quality picture or video clip-based applications, makes the UICC slow data transfer rate a real limitation. This modified version of the well known USB Universal Serial Bus specification has been specially designed for short-distance communication between chips and is actually a minor adaptation of the technology used on personal computers.
The adaptations refer to, for example, the interface voltage supply, which is no longer limited to 3. From a Table 2. However, they also specify how information is transmitted to and from the UICC as well as the file system to use in order to store and retrieve data on the UICC card.
This is a very important aspect of the subscriber module. Each file contains one or several pieces of information and can be read individually by the user terminal. There are three sorts of files:. MF Master File is the entry point of the data structure. EF Elementary File is a set of bytes which actually represent the data stored.
DF Dedicated File which allows functional grouping of files. A UICC card can contain quite a large number of files. At the root of the tree, the UICC contains key general files, such as:. EFPL Preferred Language , which defines the preferred language to be used on the terminal user interface. The DFTelecom directory is also located at the top of the tree. DFPhonebook, which is a sub-structure containing the user-defined phone book.
For information, the following briefly describe the purpose of the EF present in the figure:. EFKeys contains the 3G ciphering and integrity keys. The additions to the existing data tree will be limited to the additions specific to EPS networks, such as the specific security key and algorithms.
More details about EPS security aspects are provided in Chapter 5. From the multiplicity of logical nodes in the architecture result many interfaces. Due to the difficulty in showing everything in a single picture, Table 2.
In CDMA, each transmission channel behaves as an interferer for the other channels. The consequence is that transmission power tuning is a key point to preserve CDMA system capacity.
This becomes critical at cell edge or in poor coverage areas, where maintaining the radio link transmission quality is often a synonym to increased transmission power. This is where soft handover helps, allowing the information to be transmitted on different links — called the active set — and adding transmission diversity gain.
As illustrated in Figure 2. Information is then recombined from the received radio links, either on the network or on the terminal side, for the sake of transmitted power and associated interference.
However, soft handover does not apply to HSDPA data transmission, which makes use of a physical shared channel. This is also a consequence of the fact that uplink and downlink soft handover was actually defined as a RNC level feature. Supports control and mobility procedures for non-3GPP access technologies. Supports user and bearer information exchange for inter-system mobility in idle or active state.
Supports user plane data transfer for inter-system mobility. Supports bearer management and user plane data tunnelling between the two gateways. Based on GTP. Supports the procedures for user subscription data retrieval and location update. Based on Diameter. It supports packet and user plane transfer between the two gateways for the roaming cases.
This interface is a variant of S7 for the roaming cases. S10 Between the MME nodes. This interface is used in case of inter-MME mobility or relocation to exchange session and user contexts between nodes.
Supports bearer management e. X2 Between eNodeBs. Supports mobility and user plane tunnelling features. Based on the same user plane protocol as S1. Used to provide service dynamic information to the PCRF. Based on the FTP protocol.
Supports charging information transfer to the CDF. The cost for having an Iur interface is not negligible from an operational perspective. When an operator mixes equipments from different manufacturers in the access network, or decides to upgrade parts of it, lots of care has to be taken on interoperability between the RNC nodes being connected through the Iur. In addition, the Iur requires the operator to pay for supporting the inter-RNC connectivity and the traffic sent over the Iur.
In any case, even if Iur is not needed in most of the soft handover cases because all the cells involved in the active set are controlled by the same RNC , there is still the cost of multiple Iub link transmission to be supported between the SRNC and all the BTS.
The side effects of the Iur interface have, however, to be mitigated by the fact that a RNC can control a large number of cells, so that the Iur is actually only needed at the edge of the RNC area.
The actual figure depends, of course, on the implementation and physical capacity of each RNC, as well as the traffic load. In any case, it is usually admitted that a RNC can control several hundreds of cells. CDMA macro-diversity therefore has significant impacts in terms network architectural definition and network operation.
Soft handover is no longer needed or required, which is a significant change in terms of overall access network definition and operation. More details about X2 usage are provided in Chapter 5. In principle, this would not be a problem by itself, except for some specific radio mobility cases, which the CDMA radio interface is not able to work out without some additions.
When moving around cells of the same frequency, the terminal CDMA receiver can quite easily monitor them — build its own list of best cell, so that the active set is managed at best, thanks to the soft handover mechanism. However, problems arise in the case of multi-frequency or multi-access technol- ogy deployment, as is more and more the case in countries where cellular communications have reached maturity. When continuously receiving radio frames, the CDMA terminal has no time to switch its receiver to another frequency, and monitor neighbouring cells, e.
There may be multiple solutions to this issue. The most obvious one would be to build multiple receiver terminals, which is a very costly and power-consuming option. Another solution brought by the 3GPP standard was to change the CDMA radio frame structure in order to artificially create some holes so that the terminal has time to perform other frequency of even radio-system monitoring.
Spreading Factor reduction: in this method, the same amount of data is sent in half the time thanks to the use of a reduced SF code.
The decrease in spreading gain is then compensated by increased power during the time the code is used. Higher Layer Scheduling: this method is only suitable for non-real time communi- cations, as it relies on the MAC data scheduler to limit data transmission at some specific time. There is no ideal method, and both of them have drawbacks. The Spreading Factor reduction method requires more transmission power and creates more interference when the compressed mode is active, which has some impact on network capacity.
The second method only results in a slight increase in radio transmission latency, but it is not applicable to circuit services like voice. This leaves the possibility for an E-UTRAN terminal to monitor neighboring beacons, frequencies and systems when it is not required to receive or transmit data on the radio interface.
Regarding DSCH, it was actually never developed and deployed as a commercial solution because of its high degree of complexity and the lack of real performance improvement. Thanks to new modulation scheme and fast HARQ packet repetition scheme, the radio performances were significantly better than before. However, HSDPA still relies on an associated dedicated channel used in downlink for power control commands. A dedicated physical channel is also present in uplink to carry HARQ indications and channel quality information.
In practice, all three transmission schemes Figure 2. For circuit-based services requiring constant delay and bandwidth, transmission on DCH will still be applicable until HSDPA allows cost-efficient guaranteed bit rate solution. Although this puts more constraints on the radio scheduler in the sense that the system needs to ensure that all data flows are transmitted with the requested Quality of Service , there is only one unique solution for user data transmission which is a major simplification for network design and operation.
It is no more needed to partition radio interface physical resources in different and competing sets of shared or dedicated channels. The demand for higher data rate. The expectations of additional 3G spectrum allocations. The competition with unlicensed technologies like WiMAX. Therefore, the objectives of the system will roughly be:. Increased cell edge bits rate. Reduced latency: reduce the latency between RRC states change — from idle to active state — and for transmission over the network radio access less than 5 ms.
Scaleable bandwidth. Reduced operation cost. Acceptable system and terminal complexity, cost and power consumption. Compatibility with previous releases and with other systems. For most international experts, members of standardization bodies, it is granted now that these two technologies will be added to the technological E-UTRAN puzzle whose original 3G system is the very first foundation.
They present indeed some advantages with respect to 2G CDMA in terms of flexibility of resources allocation for packet transmissions and data rate increase for a given complexity. We will describe in a first part the main principles of these technologies and their variants before focusing in a second part on the E-UTRAN technologies as such. This technology came back in the s for the application to multipath channels.
These multi-carrier modulations became practically interesting, since a completely nu- merical structure of a modulator was highlighted based on Fast Fourier Transform FFT.
In addition, this technology is used in the broadband wireless packet access of radio called WiMAX. The OFDM technology is thus a well known technique which consists of multiplexing on frequency subcarriers some information to be transmitted on a channel of communication. Moreover, the subcarriers are orthogonal between them, owing to the fact that the minimal duration of information carried by each subcarrier is the reverse of the value of the band of modulation of the subcarrier Nyquist criterion.
Figure 3. A signal carrying information must be transmitted by a transmitter, to be received and interpreted by a receiver. The information carried by this signal includes a succession of binary characters.
Let Xn indicate a quantity of information in series to be transmitted for the n-user. Initially, a module transforms this flow series into several N parallel flows Xn,0, Xn,1. On a purely illustrative basis, each one of these parallel flows can consist of a succession of binary characters of duration equal to Tu.
This OFDM symbol represents a set of binary data coded on frequencies separated by the modulation band as indicated above. This modulation band obviously depends on the modulation chosen to create on each subcarrier a modulated symbol — we represent a classical QAM Quadrature Amplitude Modulation in Figure 3.
The OFDM symbol Sm is then transmitted by the transmitter on a channel of communica- tion which can be a radio channel, for example. From the reception side, the receiver, while listening to the channel, receives a symbol Sm corresponding then to the transmitted symbol OFDM Sm, putting aside disturbances, intro- duced by the channel or external interferences. The pulse shaping filters of Figure 3.
Indeed, when the communication channel on which the signal is transmitted includes multipaths, as it is generally the case for an urban radio channel, jamming replicas of the signal can be received at the receiver with respective delays corresponding to the various paths.
It thus results in a certain overlapping between portions of signal relative to successive OFDM symbols, likely to make more difficult the estimate of information transmitted and thus to degrade the quality of the reception. The guard time interval consists of increasing the duration of each useful symbol OFDM, by duplicating at the end of the symbol certain binary characters placed at the beginning of this symbol, or conversely.
Obviously, this part of redundant information can be a prefix, i. The receiver then benefits from the duplication of certain binary characters to improve the estimate of the useful information of each symbol.
This operation contributes to transform the convolution of the signal by the channel response into a cyclic convolution property of the circulating matrix , making easy the demodulation of the symbol transmitted on each subcarrier. Mathematically, the basic idea of OFDM thus consists of dividing the band available into N sub-bands and transmitting in each one of them to an N times weaker rate than that which would be used in the total band.
Subcarriers must be as close as possible, while preserving the orthogonality. We will see that the equalization then becomes extremely simple. For instance, assuming f0 is the bandwidth subcarrier,! The signal s t can be sampled at the frequency 2. To sum up: Advantages of OFDM for mobile radio The advantages of the modulation OFDM essentially come from its performance in comparison with the simplicity of realization of the associated receiver, which incorporates only one device intended for carrying out the FFT of the received signal followed by a simplified equalizer correcting on each subcarrier the resulting flat fading one constant complex gain per subcarrier.
The orthogonality between subcarriers allows a huge spectral efficiency. No intra-cell interference cancellation system is required. Moreover the OFDM has other advantages, with respect to the good filling of the spectrum or flexible allowance of the frequencies. No one can today easily predict the evolutions allowed by the regulatory bodies dealing with the frequency spectrum in all the countries of the world. If the United States seems technology agnostic when compared to the rest of the world, it remains that certain military applications or television broadcasters occupy many portions of spectrum and do not intend to be dislodged that easily.
However, it is particularly important to find some bands not too high in frequencies, to offer a reasonable range in cellular telephony for reasonable cost. It is one of the interests of the OFDM to be able to fill the small holes within a spectrum already partly allocated, while placing here and there the adequate number of subcarriers. Moreover, the final Fourier Transform can then be replaced by several Fourier Transform with less complexity granted the convexity of the log function [complexity of a fast transform of Fourier is in N.
N, but n. In case a feedback on the quality of the channel is available on the downlink, a base station can allocate to a user the better data rate on the better subcarriers in the signal-to- noise ratio sense, optimizing in mean the data rate for all users. Si Figure 3. It resists well to multipaths, allows a high spectral efficiency, especially with its MIMO compatibility, and a reduced complexity of implementation. In OFDM systems, there are several processes of multiple accesses which can be used to distinguish the users.
One of the simplest consists of choosing for a user given a unique law of choice of subcarrier frequencies. More precisely, each user is characterized by the choice of a set resource chosen in the frequency—time plane. The traffic multiplexing is performed by allocating to each user a pattern of frequency—time slots, depending on its data rate.
From a frequency point of view, according to the choice of mapping of symbols on subcarriers, the subcarriers allocated to one joint can be joint or separated. From a frequency diversity point of view, the separated scheme is obviously better. The scheme on the left provides much more diversity than the second one. Common control channels bring classically some information on the network, the cell, etc. Pilot symbols are useful to perform the identification of the channel response.
Thanks to these known symbols, channel response can be interpolated both in time and frequency and simply equalized, as we will see in the following paragraph. It has been shown from a frequency and time channel sounding perspective that a good way of arranging these pilot symbols is to place them so that they form some diagonals in the time— frequency space.
H can be diagonalized and its eigenvectors is the FFT of the pattern. In this technique, like in classical CDMA, some spreading codes are used to multiplex the different users on a code-per-code basis before distributing the resulting summation on the OFDM subcarriers. This way of arranging the multiple access schemes is mentioned here in this section as it is a scheme that many actors of telecommunications, especially in Japan, advocated for in a fourth-generation context.
Eventually, this leads to a unified representation of these processes of modulation or transformation of the signal in order to bring the two worlds closer. For demonstration, we introduce a complex vector X n.
Ts ]T containing a whole of N independent symbols of communications. These symbols must be transmitted in the same Ts time interval from a basic station or an access node to some terminals. N for which each column represents a particular sequence of spreading.
Ts symbol. The vectors S n. Thanks to the insertion of a prefix for the OFDM or even for the CDMA and to its suppression in the receiver, the impulse response of the channel is finished and the receiver can only consider the symbols resulting from the vector X n.
N matrix. Ts is a white noise of power spectrum density N0 such that E N n. In the gap time [n. Z estimate and X. WH represents the Hermitian transform of the W matrix. Therefore, an accurate frequency drift estimator is often necessary in OFDM receivers. Correct performance of admission control algorithms and load balancing ones depends on the current expression of the load of the system.
Contrary to the CDMA system, the OFDMA system load is not a direct function of the intra and inter-cell interferences, but a function of time—frequency—space resource assignments and power resource assignments. The power control, for instance, was of primary importance in WCDMA to mitigate the near—far effect deriving from the presence of the intra-cell interference, whereas in OFDM systems, like the E-UTRAN system, the users of a same cell are as orthogonal as possible with each other; thus, the only interference present is from the other cells intercell.
Though, still important, the role of the power control is reduced, compared to CDMA, to adapting the power to path loss and shadow fading fluctuations and reducing other cell interference.
Adaptations of parameters are the set of the assigned downlink subcarriers, coding, modulation, HARQ schemes including the spatial coding schemes and transmission power values. Examines UMTS and the testing of UMTS devices which are huge areas in the testing process Provides essential information on processes and techniques for mobile phone testing Operation of the UMTS standard is described from a test point of view Focuses on most important areas of the 3rd-Generation Partnership Project 3GPP standard from a test perspective Offers advice on products, services and resources that aid the testing process.
This book is an ideal text for engineers and managers who are either directly involved in the process of testing UMTS mobiles, or who are looking for an understanding of what is involved in testing. Professionals involved in the development of UMTS mobiles, integration and verification, conformance testing, operator acceptance testing, manufacturing and servicing will find this book indispensable.
The 19 revised full papers presented together with three invited contributions were carefully reviewed and selected from 53 submissions. Networkelement instability, network element and multi-vendorinteroperability, configuration and network planning faults arejust a few of the challenges affecting performance andprofitability that need to be addressed.
This book is an invaluableguide to resolving such problems. It will also be an invaluable resource forpostgraduates on telecommunications courses, especially those witha focus on signal analysis.
The tools and techniques discussed apply to conformance testing, interoperability testing, performance testing, Internet protocols and applications, and multimedia and distributed systems in general.
In total, 39 research papers were submitted for consideration, and after full refereeing by international referees, 27 papers from authors in 11 countries were accepted for publication. The symposium brought together 60 active international researchers and telecommunications engineers to discuss the important questions as to whether there is a convergence of all communications, including real-time communications, over the Internet Protocol IP , and whether existing IP technology is capable of supporting this convergence, or whether it requires further development of that technology.
The papers selected to appear in this volume make an important and timely contribution to this debate. Specific symposium paper sessions were held to present and discuss ernerging research on the topics of converged networking, real-time communications over IP, quality of service, routing and metrics, ernerging issues in mobile networks, differentiated services, and wireless networking. This book has been designed to guide the students of the Bachelor's in Telecommunications Technology Engineering towards a clear understanding of how to use the laboratory tools, and show them how to analyze and understand the collected measurements.
In this context, the book first introduces and describes how to use the professional measurement tools employed in the laboratory activities of the mobile communications course at UMH. These tools are commonly used by cellular radio engineers to monitor in real-time the performance of cellular networks through drive tests.
The book is unique in that it systematically compares how a. Designing Software for the Mobile Context. Roman Longoria The goal of this book is to provide a useful and timely guide to the practitioner who designs or develops mobile applications. The contributors to this book are leaders in the user interface UI community actively working in mobile platform technol ogy and mobile application design. Thus, this. UMTS Signaling.
Written specifically for readers with no prior knowledge of computing, electronics, or logic design. A full list of references, and a set of exercises are also provided at the end of the book to test comprehension and strengthen understanding of the material.
The evolution of mobile communication standards presents numerouschallenges in mobile handset design. Designers must continue toturn out handsets that maintain high device performance and airinterface compatibility, while at the same time shrink powerconsumption, form factors, and costs.
Mobile Handset Design is uniquely written to equipprofessionals and students with a complete understanding of how amobile phone works, and teaches the skills to design the latestmobile handsets. He presents all problems associated withmobile wireless channels and recommends corresponding designsolutions to overcome those issues.
Mobile RF front-end, digitalbaseband design techniques, and associated trade-offs are alsocovered. Das also discusses the productization aspects and reviewsnew research developments for different mobile phone systems overgenerations. Teaches basic working principles of legacy and 4G mobilesystems Vividly illustrates and explains all key components and theanatomy of mobile phones Explains all hardware and software blocks, from principle topractice to product Discusses key design attributes such as low power consumptionand slim form factors Moves through all topics in a systematic fashion for easycomprehension Presentation files with lecture notes available for instructoruse This book is essential for practicing software, hardware and RFdesign engineers and product managers working to create innovate,competitive handsets.
Mobile Handset Design is also idealfor fresh graduates or experienced engineers who are new to themobile industry, and is well-suited for industry veterans as ahandy reference.
This book is the first of its kind, compiling information on the Long-Term Evolution LTE standards, which are enhanced to address new mobility-related challenges in Heterogeneous Networks HetNets. It identifies the related challenges and discusses solutions and the simulation methodology for modeling HetNet mobility — cutting-edge information that was previously accessible only in the form of 3GPP specifications and documents, and research papers.
The book reviews the current LTE mobility framework and discusses some of the changes for enhancing mobility management in HetNets. HetNets are intended to provide very high spectral efficiency while ensuring seamless coverage by deploying low-power nodes within the umbrella macrocell network. While mobility management in homogeneous networks is well understood, LTE standards are being enhanced to address the HetNet-specific mobility management challenges emerging.
The book addresses these aspects in a succinct and understandable form, offering a valuable resource for researchers and professionals working in the area of HetNet mobility and a ready reference guide for practicing engineers and researchers. The main content is based upon the release 6 version of the 3GPP specifications. Changes since the release 99 version are described while some of the new features from the release 7 version are introduced.
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