This thesis addresses handoff issues in a WCDMA system with space-time block coded transmit antenna diversity. Soft handoff has traditionally been used in CDMA systems because of its ability to provide an improved link performance due to the inherent macro diversity. Next generation systems will incorporate transmit diversity schemes employing several transmit antennas at the base station. These schemes have been shown to improve downlink transmission performance especially capacity and quality. This research investigates the possibility that the diversity obtained through soft handoff can be compensated for by the diversity obtained in a transmit diversity system with hard handoff. We analyze the system for two performance measures, namely, the probability of bit error and the outage probability, in order to determine whether the improvement in link performance, as a result of transmit diversity in a system with hard handoffs obviates the need for soft handoffs.

<p>This thesis treats the development of wirelessinfrastructure standards resulting from co-operative research,development and standardisation efforts. It strives to identifykey influences on this development process, and toconceptualise the process itself. With this as a basis, it goeson to analyse potential implications for companies in thewireless industry, and for the role of co-operatively developedstandards in this field. The focus of the thesis is on thecreation of standards through development efforts, rather thanthe selection of standards in official forums, or by themarket.</p><p>Two deep empirical studies provide the foundation of thethesis. The first one deals with the development of the DigitalEnhanced Cordless Telecommunications (DECT) standard. DECT isan open, de jure standard that was designed by a number oftelecommunications manufacturers. The standard was formallyapproved by the European Telecommunications Standards Institute(ETSI) in 1992. The second study treats the development ofThird Generation (3G) mobile infrastructure standards, withspecial focus on the radio interface standards such as WidebandCode Division Multiple Access (WCDMA). The development of thefamily of 3G standards today known as International MobileTelecommunications 2000 (IMT-2000) began more than 15 yearsago, and the first version of formally adopted air interfacestandards was released in 2000 by the Third GenerationPartnership Project (3GPP). The research and development goinginto the specification of the standards has involved all majorplayers in the wireless industry.</p><p>The two studies have involved numerous interviews withindustry professionals, academics, regulators, and others. Inaddition, a multitude of technical reports and articles,meeting documents, press releases, etc., have been analysed toprovide good documentation of the development processes. Theempirical studies have also been complemented with extensiveliterature studies into the areas of technical development andstandardisation.</p><p>Apart from two "thick descriptions" of importantdevelopments in the wireless industry, the main result of thethesis is a conceptual framework for how wirelessinfrastructure standards are developed. The frameworkdemonstrates that the development is influenced by thepre-history of the standard in terms of existing systems, aswell as research and development that had been pursued inrelevant fields. Furthermore it shows that preconceptions ofmarket needs and user behaviour are key aspects of the designof the standard. During the development process technologicalcontroversies tend to appear as a manifestation of differentcompetitive intentions among the involved players. In theresolution of these controversies, the stage is set for futurecompetition between suppliers of products adhering to thestandard.</p><p>The pre-history of a standard, as well as the marketpreconceptions, originate in the semi-independent processes oftechnological development, and market diffusion, respectively.When the time frame of the conceptual framework is expanded,generations of standards following upon each other can beidentified. Each new generation incorporates new developments,and improved functionality and performance, but also builds onexisting solutions. The technical standards, such as DECT orWCDMA, act as wasp-like waists between the technologicaldevelopment and the market diffusion processes.</p><p>The thesis shows that wireless infrastructure standards to agreat extent are created through technical development efforts.The processes also involve political, competitive, andregulatory deliberations, but technical content often definesthe form even for these debates. This points to the importanceof considering standards-setting in terms of a developmentprocess rather than as a set of formal decisions made by astandards body. A consequence of this is that companiesdesiring to influence the design of a particular standardshould strive to be in the forefront of research anddevelopment related to that standardisation effort. This is thekey to leading the development of new wireless infrastructurestandards.</p><p><b>Key words:</b>standards, de jure standards,standardisation, standards-development, competition,technological development, wireless communications, wirelessinfrastructures, telecommunications, WCDMA, DECT, IMT-2000,FPLMTS, 3G</p>

Abstract High computational complexity constrains truly exhaustive computer searches for good space-time (ST) coded modulations mostly to low constraint length space-time trellis codes (STTrCs). Such codes are primarily devised to achieve maximum transmit diversity gain. Due to their low memory order, optimization based on the design criterion of secondary importance typically results in rather modest coding gains. As another disadvantage of limited freedom, the different low memory order STTrCs are almost exclusively constructed for either slow or fast fading channels. Therefore in practical applications characterized by extremely variable Doppler frequencies, the codes typically fail to demonstrate desired robustness. On the other hand, the main drawback of eventually increased constraint lengths is the prohibitively large decoding complexity, which may increase exponentially if optimal maximum-likelihood decoding (MLD) is applied at the receiver. Therefore, robust ST coded modulation schemes with large equivalent memory orders structured as to allow sub-optimal, low complexity, iterative decoding are needed. To address the aforementioned issues, this thesis proposes parallel concatenated space-time turbo coded modulation (STTuCM). It is among the earliest multiple-input multiple-output (MIMO) coded modulation designs built on the intersection of ST coding and turbo coding. The systematic procedure for building an equivalent recursive STTrC (Rec-STTrC) based on the trellis diagram of an arbitrary non-recursive STTrC is first introduced. The parallel concatenation of punctured constituent Rec-STTrCs designed upon the non-recursive Tarokh et al. STTrCs (Tarokh-STTrCs) is evaluated under different narrow-band frequency flat block fading channels. Combined with novel transceiver designs, the applications for future wide-band code division multiple access (WCDMA) and orthogonal frequency division multiplexing (OFDM) based broadband radio communication systems are considered. The distance spectrum (DS) interpretation of the STTuCM and union bound (UB) performance analysis over slow and fast fading channels reveal the importance of multiplicities in the ST coding design. The modified design criteria for space-time codes (STCs) are introduced that capture the joint effects of error coefficients and multiplicities in the two dimensional DS of a code. Applied to STTuCM, such DS optimization resulted in a new set of constituent codes (CCs) for improved and robust performance over both slow and fast fading channels. A recursive systematic form with a primitive equivalent feedback polynomial is assumed for CCs to assure good convergence in iterative decoding. To justify such assumptions, the iterative decoding convergence analysis based on the Gaussian approximation of the extrinsic information is performed. The DS interpretation, introduced with respect to an arbitrary defined effective Hamming distance (EHD) and effective product distance (EPD), is applicable to the general class of geometrically non-uniform (GNU) CCs. With no constrains on the implemented information interleaving, the STTuCM constructed from newly designed CCs achieves full spatial diversity over quasi-static fading channels, the condition commonly identified as the most restrictive for robust performance over a variety of Doppler spreads. Finally, the impact of bit-wise and symbol-wise information interleaving on the performance of STTuCM is studied.

This thesis treats the development of wirelessinfrastructure standards resulting from co-operative research,development and standardisation efforts. It strives to identifykey influences on this development process, and toconceptualise the process itself. With this as a basis, it goeson to analyse potential implications for companies in thewireless industry, and for the role of co-operatively developedstandards in this field. The focus of the thesis is on thecreation of standards through development efforts, rather thanthe selection of standards in official forums, or by themarket. Two deep empirical studies provide the foundation of thethesis. The first one deals with the development of the DigitalEnhanced Cordless Telecommunications (DECT) standard. DECT isan open, de jure standard that was designed by a number oftelecommunications manufacturers. The standard was formallyapproved by the European Telecommunications Standards Institute(ETSI) in 1992. The second study treats the development ofThird Generation (3G) mobile infrastructure standards, withspecial focus on the radio interface standards such as WidebandCode Division Multiple Access (WCDMA). The development of thefamily of 3G standards today known as International MobileTelecommunications 2000 (IMT-2000) began more than 15 yearsago, and the first version of formally adopted air interfacestandards was released in 2000 by the Third GenerationPartnership Project (3GPP). The research and development goinginto the specification of the standards has involved all majorplayers in the wireless industry. The two studies have involved numerous interviews withindustry professionals, academics, regulators, and others. Inaddition, a multitude of technical reports and articles,meeting documents, press releases, etc., have been analysed toprovide good documentation of the development processes. Theempirical studies have also been complemented with extensiveliterature studies into the areas of technical development andstandardisation. Apart from two "thick descriptions" of importantdevelopments in the wireless industry, the main result of thethesis is a conceptual framework for how wirelessinfrastructure standards are developed. The frameworkdemonstrates that the development is influenced by thepre-history of the standard in terms of existing systems, aswell as research and development that had been pursued inrelevant fields. Furthermore it shows that preconceptions ofmarket needs and user behaviour are key aspects of the designof the standard. During the development process technologicalcontroversies tend to appear as a manifestation of differentcompetitive intentions among the involved players. In theresolution of these controversies, the stage is set for futurecompetition between suppliers of products adhering to thestandard. The pre-history of a standard, as well as the marketpreconceptions, originate in the semi-independent processes oftechnological development, and market diffusion, respectively.When the time frame of the conceptual framework is expanded,generations of standards following upon each other can beidentified. Each new generation incorporates new developments,and improved functionality and performance, but also builds onexisting solutions. The technical standards, such as DECT orWCDMA, act as wasp-like waists between the technologicaldevelopment and the market diffusion processes. The thesis shows that wireless infrastructure standards to agreat extent are created through technical development efforts.The processes also involve political, competitive, andregulatory deliberations, but technical content often definesthe form even for these debates. This points to the importanceof considering standards-setting in terms of a developmentprocess rather than as a set of formal decisions made by astandards body. A consequence of this is that companiesdesiring to influence the design of a particular standardshould strive to be in the forefront of research anddevelopment related to that standardisation effort. This is thekey to leading the development of new wireless infrastructurestandards. Key words:standards, de jure standards,standardisation, standards-development, competition,technological development, wireless communications, wirelessinfrastructures, telecommunications, WCDMA, DECT, IMT-2000,FPLMTS, 3G / <p>NR 20140805</p>

User modeling enables in the computation of the traffic density in a cellular network, which can be used to optimize the placement of base stations and radio network controllers as well as to analyze the performance of resource management algorithms towards meeting the final goal: the calculation and maximization of network capacity and throughput for different data rate services. An analytical model is presented for approximating the user distributions in multi-cell third generation wideband code division multiple access (WCDMA) networks using 2-dimensional Gaussian distributions by determining the means and the standard deviations of the distributions for every cell. This model allows for the calculation of the inter-cell interference and the reverse-link capacity of the network. An analytical model for optimizing capacity in multi-cell WCDMA networks is presented. Capacity is optimized for different spreading factors and for perfect and imperfect power control. Numerical results show that the SIR threshold for the received signals is decreased by 0.5 to 1.5 dB due to the imperfect power control. The results also show that the determined parameters of the 2-dimensional Gaussian model match well with traditional methods for modeling user distribution. A call admission control algorithm is designed that maximizes the throughput in multi-cell WCDMA networks. Numerical results are presented for different spreading factors and for several mobility scenarios. Our methods of optimizing capacity and throughput are computationally efficient, accurate, and can be implemented in large WCDMA networks.

This thesis concentrates on the UMTS cellular network and the possibilities of its monitoring. There are several methods of monitoring the UMTS. The technique used in this project is based on monitoring through a cellular terminal. The theoretical part is devoted to the description of the UMTS system and the WCDMA technique. The practical part then deals with the method of UMTS monitoring through a cellular terminal and describes in detail individual screens of the FTD (Field Test Display) program, the Netmonitor functions and their parameters. The next part of this thesis analyses the RRC messages, which were recorded during the realization of services (video calls, calls, data transfers) in the UMTS network. The last chapters of the thesis are briefly dealing with software and hardware servicing of cellular terminals. The attachment then offers two lab tasks, in which the students get acquainted with the UMTS network structure and the behaviour of the cellular terminal in this network.

With high date rates using Enhanced Uplink (EUL), a conventional signal to interference ratio (SIR) based power control algorithm may lead to a power rush due to self interference or incompatible SIR target [2]. Time division (TD) scheduling in Wideband Code Division Multiplex Access (WCDMA) is considered to be a key feature in achieving high user data rates. Unfortunately, power oscillation/peak is observed in time division multiplexing (TDM) at the transition between active and inactive transmission time intervals [1]. Therefore there is a need to revisit power control algorithms for different time division scheduling scenarios. The objective of power control in the context of this study is to minimize the required rise over thermal noise (RoT) for a given data rate, subject to the constraint that the physical layer control channel quality is sufficient (assuming that the dedicated physical control channel (DPCCH) SIR should not go below 3dB with a probability of at most 5%). Another goal is to minimize the local oscillation in power (power peaks) that may occur, for example due to transitions between active and inactive transmission time intervals. The considered hybrid power control schemes are: (1) non-parametric Generalized rake receiver SIR (GSIR) Inner Loop Power Control (ILPC) during active transmission time intervals + Received Signal Code Power (RSCP) ILPC during inactive transmission time intervals and (2) RSCP ILPC during active transmission time intervals + GSIR ILPC during inactive transmission time intervals. Both schemes are compared with pure GSIR and pure RSCP ILPC. Link level simulations with multiple users connected to a single cell show that: The power peak problem is obviously observed in GSIR + GSIR transmit power control (TPC), but in general it performs well in all time division scenarios studied. GSIR outperforms other TPC methods in terms of RoT, especially in the TU channel model. This is because it is good in combating instantaneously changed fading and accurately estimates SIR. Among all TPC methods presented, GSIR + GSIR TPC is best in maintaining the quality of the DPCCH channel. No power rush is observed when using GSIR + GSIR TPC. RSCP + RSCP eliminates the power peak problem and outperforms other TPC methods presented under the 3GPP Pedestrial A (pedA) 3km/h channel in terms of RoT. However, in general it is worse in maintaining the control channel’s quality than GSIR + GSIR TPC. GSIR + RSCP ILPC eliminates the power peak problem and out-performs GSIR power control in the scenario of 2 and 4 TDM high data rate (HDR) UE and 2 TDM HDR UE coexistence with 4 Code DivisionMultiplex (CDM) LDR UE, in the pedA 3km/h channel, in terms of RoT. However, the control channel quality is not maintained as well during inactive transmission time intervals. It is not recommended to use RSCP + GSIR TPC since it performs worst among these TPC methods for most of the cases in terms of RoT, even though it is the second best in maintaining the control channel quality. The power peak is visible when using RSCP + GSIR TPC. To maintain the control channel’s quality, a minimum SIR condition is always used on top of all proposed TPC methods. However, when there are several connected TDM HDR UEs in the cell, results indicates that it is challenging to meet the quality requirement on the control channels. So it may become necessary to limit the number of connected terminals in a cell in a time division scenario. / Med den höga datahastighet som Enhanced Uplink (EUL) medger kan en konventionell algoritm för effektkontroll baserad på signal to interference ratio (SIR) leda till effekthöjning beroende på självinterferens eller felaktigt SIR mål. Time division (TD) schedulering vid Wideband Code Division Multiple Access (WCDMA) anses vara en nyckelfunktion för att uppnå höga datahastigheter. I övergången mellan aktiv och inaktiv transmissionstidsintervall vid time division multiplexing (TDM) har effektoscillering/effektpeak observerats. Detta gör det nödvändigt att se över algoritmerna för effektkontroll vid olika scenarion av TD schedulering. Målet med effektkontrollen i denna studie är att minimera rise over thermal noise (RoT) för en given datahastighet givet begränsningen att kvaliteten på physical layer control channel är tillräcklig (beaktande att dedicated physical control channel (DPCCH) SIR inte understiger 3dB med en sannolikhet på som mest 5%). Ett annat mål är att minimera den lokala effektoscillationen (effektpeakar) som kan inträffa till exempel vid övergång mellan aktiv och inaktiv transmissionstidsintervall. De undersökta hybrida metoderna för effektkontroll är: (1) icke-parametrisk Generalized rake receiver SIR (GSIR) Inner Loop Power Control (ILPC) vid aktiv transmissionstidsintervall + Received Signal Code Power (RSCP) ILPC vid inaktiv transmissionstidsintervall och (2) RSCP ILPC under aktiv transmissionstidsintervall + GSIR ILPC under inaktiv transmissiontidsintervall. Båda metoderna jämförs med ren GSIR och ren RSCP ILPC. Länk nivå simulering med flera användare anslutna till en enda cell visar att: Problemet med effektpeakar observeras tydligt vid GSIR + GSIR transmit power control (TPC) men generellt sett presterar den bra i alla studerade TD scenarion. GSIR presterar bättre än andra TPC metoder beträffande RoT, speciellt i TU kanal modellen. Detta beror på att metoden är bra på att motverka momentant förändrad fading och med god precision estimerar SIR. Bland alla presenterade TPC metoder är GSIR + GSIR TPC den bästa på att behålla en god kvalitet på DPCCH kanalen. Ingen effekthöjning har observerats vid GSIR + GSIR TPC. RSCP + RSCP eliminerar problemet med effektpeakar och presterar bättre än andra TPC metoder presenterade under 3GPPs Pedestrial A (pedA) 3km/h kanal beträffande RoT. Dock är metoden generellt sett sämre på att behålla kontrollkanalens kvalitet än GSIR + GSIR TPC. GSIR + GSIR ILPC eliminerar problemet med effektpeakar och presterar bättre än GSIR power control i ett scenario med 2 och 4 TDM high data rate (HDR) UE och 2 TDM HDR UE tillsammans med 4 Code Division Multiplex (CDM) LDR UE i pedA 3km/h kanalen beträffande RoT. Dock kan inte kvaliteten på kontrollkanalen behållas i detta fall heller under inaktiv transmissionstidsintervall. Det är inte rekommenderat att använda RSCP + GSIR TPC eftersom den presterar sämst av alla TPC metoder beträffande RoT i de allra flesta fall. Till dess fördel är att den är den näst bästa på att behålla kvaliteten på kontrollkanalen. Effektpeakar har observerats när RSCP + GSIR TPC använts. För att behålla kontrollkanalens kvalitet används alltid en minimum SIR nivå ovanpå alla föreslagna TPC metoder. När det finns flera anslutna TDM HDR UEs i cellen indikerar resultaten att det är en utmaning att behålla kvalitetskraven på kontrollkanalen. På grund av detta kan det bli nödvändigt att begränsa antalet anslutna terminaler i en cell i ett TD scenario.

It has long been recognized that in multi-cell WCDMA networks the admission of a new session into the system can have undesirable impact on the neighboring cells. Although admission control algorithms that take into account such multi-cell impact have been studied in the past, little attention has been paid to multi-cell admission and rate control algorithms when traffic is elastic. In this thesis, we propose a model for multi-cell multi-service WCDMA networks to study the impact of multi-cell admission and rate control algorithms on key performance measures such as the class-wise blocking and outage probabilities, block error rates, and the noise rise violation probabilities. By means of simulation we compare the performance of load based multi-cell algorithms with that of a single cell algorithm. We find that with multi-cell based algorithms the system capacity and performance (in terms of the above mentioned measures) are (in some cases significantly) better in homogeneous load scenarios as well as in the heterogeneous ’hotspot’ and ’hotaround’ scenarios. / Det har länge varit känt att i multi-cellulära WCDMA nät så kan insläppandet av en ny användarei systemet ha en icke önskvärd effekt på intilliggande celler. Fastän insläppskontrollalgoritmer (AC)som tar hänsyn till sådana multi-cellulära effekter har studerats tidigare, så har endast begränsaduppmärksamhet ägnatsåt multi-cellulär insläpps- och bittaktskontrollalgoritmer när trafiken är elastisk.I detta arbete föreslår vi en modell för WCDMA-nät med multipla celler och multipla tjänster ochsom är applicerbar för studier av av hur multi-cellulär insläpps- och bittaktskontroll inverkar påviktiga prestandamått som klassvisa spärr- och utslagningssannolikheter, blockfelssannolikheter, ochsannolikheten för överträdande av tillåten interferensnivå. Med simuleringar jämför vi prestanda förlastbaserade multi-cellalgoritmer med prestanda för singel-cellalgoritmer. Vi har funnit att med multicellalgoritmerså är systemskapacitetet och prestanda (i termer av tidigare nämnda mått) i några fallbetydligt bättre i homogena lastscenarier, samt i heterogena lastscenarier av typerna ’hotspot’ och’hotround’.

Universal Mobile Telecommunications Systems (UMTS) is the preferred third generation (3G) communication standard for mobile communications and will provide worldwide coverage, a convenient software technology and very high data rate. The high data rate, especially, requires the use of bandwidth-efficient modulation schemes such as Quadrature Phase Shift Keying (QPSK). But modulation schemes such as QPSK need, in turn, a very linear power from the output of the transmitter power amplifier in order to meet the spectral requirements. A linear power amplifier, traditionally, has very low energy efficiency. Poor energy efficiency directly affects operational costs and causes thermal heating issues in base station transmitters. Thus the power amplifier designer is forced to trade-off between linearity and efficiency. As a result of this trade-off a Class-AB power amplifier is most often used in QPSK based systems. Class-AB power amplifiers provide acceptable linearity at efficiency values around 45-50% typically. This compromise is not a satisfactory solution but is inevitable while using traditional power amplifier design techniques. This thesis details the use of a Class-F amplifier with carefully chosen bias points and harmonic traps to overcome this problem. Class-F amplifiers are usually considered as very high efficiency (80% or more power-added efficiency) amplifiers where the high efficiency is obtained through the use of harmonic traps (L-C filters or quarter-wavelength transmission lines), which provide suitable terminations (either open or short) for the harmonics generated. By doing this, a square wave drain voltage and a peaked half-sinusoidal drain current out-of-phase by 180 are produced. Since only a drain voltage or a drain current exists at any given time, the power dissipation is ideally zero resulting in 100% theoretical efficiency. These very high efficiency values are usually associated with poor linearity. However the linearity can be improved to meet the design standards but compromising on efficiency. Even after this is done, efficiencies are usually 10 to 15% greater than a traditional Class AB power amplifier with similar linearity performance. Thus efficiency can be improved without affecting linearity by the use of Class-F power amplifiers. In order to verify this theory, a Class-AB and a Class-F power amplifier are designed using Motorola's high voltage laterally diffused metal oxide semiconductor (LDMOS) transistor. The choice of bias points and the design of the harmonic traps are very critical for the Class-F performance and hence were designed after careful consideration. The designs were simulated on Agilent's Advanced Design System (ADS) and the simulated results were compared for three different power levels namely, the peak power, 3 dB below peak power and 6 dB below peak power. At all of these power levels it was noted that the Class-F and Class-AB power amplifiers have very similar linearity performance whereas the Class-F power amplifiers show about 10% improvement in efficiency in comparison to the Class-AB power amplifiers. / Master of Science

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