Power control for WCDMA

This project tries to introduce itself in the physical implementations that make possible the denominated third generation mobile technology. As well as to know the technology kind that makes possible, for example, a video-call in real time. During this project, the different phases passed from the election of WCDMA like the access method for UMTS will appear. Its coexistence with previous network GSM will be analyzed, where the compatibility between systems has been one of the most important aspects in the development of WCDMA, the involved standardization organisms in the process, as well as the different protocols that make the mobile communications within a network UTRAN possible. Special emphasis during the study of the great contribution that has offered WCDMA with respect to the control of power of the existing signals will be made. The future lines that are considered in the present, and other comment that already are in their last phase of development in the field of the mobile technology. UMTS through WCDMA can be summarized like a revolution of the air interface accompanied by a revolution in the network of their architecture

Laajakaistaisen CDMA solukkoverkon kapasiteetti makrosoluympäristössä

Tämän diplomityön tarkoitus on tutkia kuormitetun laajakaistaiseen koodijakomenetelmään perustuvan makrosoluverkon kapasiteettia. Työn tavoitteena on selvittää simulointien avulla, miten solukkoverkon palvelemien matkaviestinten käyttäjien eri tiedonsiirtonopeudet ja liikkumisnopeudet vaikuttavat järjestelmän kokonaiskapasiteettiin. Tehonsäädön ja samalla taajuudella olevien solujen välisen kanavananvaihdon toiminnallisuuksien ja parametrien vaikutuksia tutkitaan verkon kapasiteetin kannalta Tutkimus alkaa hajaspektriteknologian perusteiden ja UMTS:n (Universal Mobile Telecommunications System) FDD (Frequency Division Duplex) osan esittelyillä. Laajakaistaisen koodijakoon perustuvan verkon kapasiteetin ominaisuudet esitellään. Makrosoluympäristö määritellään ja sen perusominaisuudet esitellään. Laajakaistaista koodijakoon perustuvaa UMTS-järjestelmää mallintava simulointiohjelmisto kuvaillaan ennen tämän diplomityön simulointien ja tulosten esittelyä ja analysointia. Tämän tutkimuksen simuloinnit suoritetaan yksinkertaisessa esikaupunkityyppisessä makrosoluympäristössä. Laajakaistaisen koodijakoon perustuvan järjestelmän kapasiteetti käyttäytyy hyvin dynaamisesti. Kapasiteetti riippuu käyttäjien jakaumasta verkossa, tiedonsiirtonopeuksista, liikkumisnopeudesta, häiriön määrästä ja tehonsäädön ja samalla taajuudella olevien solujen kanavanvaihdon parametrien valinnasta. Puhekäyttäjien lisäys vaikuttaa enemmän suuria tiedonsiirtonopeuksia kuin alhaisia tiedonsiirtonopeuksia käyttävien tilaajien palvelun laatuun. Solujen väliset häiriöt vaikuttavat merkittävästi verkon kapasiteettiin. Alhaiset tehonsäädön virheet eivät vaikuta merkittävästi hitaasti liikkuvien käyttäjien saamaan palvelun laatuun. Samalla taajuudella olevien solujen kanavanvaihdon kynnysarvo tulisi optimoida, jotta voitaisiin saavuttaa verkon suurin mahdollinen kapasiteetti ja minimoida häiriöt

Adaptive Wireless Networking

This paper presents the Adaptive Wireless Networking (AWGN) project. The project aims to develop methods and technologies that can be used to design efficient adaptable and reconfigurable mobile terminals for future wireless communication systems. An overview of the activities in the project is given. Furthermore our vision on adaptivity in wireless communications and suggestions for future activities are presented

On the modeling of WCDMA system performance with propagation data

The aim of this study was to develop calculation methods for estimating the most important system level performance characteristics of the WCDMA radio network (i.e. network capacity and coverage) in the presence of interference from various sources. The calculation methods described in this work enable the fast design of radio systems with a reasonable degree of accuracy, where different system parameters, propagation conditions and networks as well as frequency scenarios can be easily tested. The work also includes the development and verification of a propagation model for a microcellular environment. Traditionally, system level performance figures have been retrieved using system simulations where the radio network has been modeled as accurately as possible. This has included base stations and mobile stations, propagation models, traffic models and mobility models. Various radio resource management (RRM) algorithms, such as power controls and handovers have also been modeled. However, these system simulations are very complex and time consuming and typically the models are difficult to modify. The idea behind this work is to use the main statistical parameters retrieved from accurate, case specific propagation models and to use these statistics as input for the developed analytical radio network models. When used as output from these analytical models we are able to obtain the performance measures of the network. The specific application area for the developed methods is the evaluation of the effect of the interference from the adjacent frequency channels. Adjacent channel interference decreases the efficiency of the usage of the electromagnetic spectrum i.e. the spectral efficiency. The aim of a radio system design is to ensure that the reduction in the spectral efficiency is as low as possible. This interference may originate from the same or a different radio system and from the same or another operator's network. The strength of this interference is dependent on the system parameters and the network layout. The standard questions regarding adjacent system interference between different operators' network are what guard band is needed between the radio carriers in order to maintain the quality of the network or what are the main mobile and network parameters, such as adjacent channel emission levels or adjacent channel selectivity, required in order to achieve satisfactory network performance. With the developed method proposed here it is possible to answer these questions with reasonable accuracy. One important aspect of network performance is the radio wave propagation environment for which the radio systems are designed. This thesis presents methods evaluating radio wave propagation, especially for cases where the base station antenna is below the rooftops, i.e. in the case of microcellular network environments. The developed microcellular propagation model has been developed for network planning purposes and it has been verified using numerous field propagation measurements. The model can be used in cases where the mobile station is located either indoors or outdoors.reviewe

Indoor Radio Measurement and Planning for UMTS/HSPDA with Antennas

Over the last decade, mobile communication networks have evolved tremendously with a key focus on providing high speed data services in addition to voice. The third generation of mobile networks in the form of Universal Mobile Telecommunications System (UMTS) is already offering revolutionary mobile broadband experience to its users by deploying High Speed Downlink Packet Access (HSDPA) as its packet-data technology. With data speeds up to 14.4 Mbps and ubiquitous mobility, HSDPA is anticipated to become a preferred broadband access medium for end-users via mobile phones, laptops etc. While majority of these end-users are located indoors most of the time, approximately 70-80% of the HSDPA traffic is estimated to originate from inside buildings. Thus for network operators, indoor coverage has become a necessity for technical and business reasons. Macro-cellular (outdoor) to indoor coverage is a natural inexpensive way of providing network coverage inside the buildings. However, it does not guarantee sufficient link quality required for optimal HSDPA operation. On the contrary, deploying a dedicated indoor system may be far too expensive from an operator\u27s point of view. In this thesis, the concept is laid for the understanding of indoor radio wave propagation in a campus building environment which could be used to plan and improve outdoor-to-indoor UMTS/HSDPA radio propagation performance. It will be shown that indoor range performance depends not only on the transmit power of an indoor antenna, but also on the product\u27s response to multipath and obstructions in the environment along the radio propagation path. An extensive measurement campaign will be executed in different indoor environments analogous to easy, medium and hard radio conditions. The effects of walls, ceilings, doors and other obstacles on measurement results would be observed. Chapter one gives a brief introduction to the evolution of UMTS and HSDPA. It goes on to talk about radio wave propagation and some important properties of antennas which must be considered when choosing an antenna for indoor radio propagation. The challenges of in-building network coverage and also the objectives of this thesis are also mentioned in this chapter. The evolution and standardization, network architecture, radio features and most importantly, the radio resource management features of UMTS/HSDPA are given in chapter two. In this chapter, the reason why Wideband Code Division Multiple Access (WCDMA) was specified and selected for 3G (UMTS) systems would be seen. The architecture of the radio access network, interfaces with the radio access network between base stations and radio network controllers (RNC), and the interface between the radio access network and the core network are also described in this chapter. The main features of HSDPA are mentioned at the end of the chapter. In chapter three the principles of the WCDMA air interface, including spreading, Rake reception, signal fading, power control and handovers are introduced. The different types and characteristics of the propagation environments and how they influence radio wave propagation are mentioned. UMTS transport, logical and physical channels are also mentioned, highlighting their significance and relationship in and with the network. Radio network planning for UMTS is discussed in chapter four. The outdoor planning process which includes dimensioning, detailed planning, optimization and monitoring is outlined. Indoor radio planning with distributed antenna systems (DAS), which is the idea and motivation behind this thesis work, is also discussed. The various antennas considered and the antenna that was selected for this thesis experiment was discussed in chapter five. The antenna radiation pattern, directivity, gain and input impedance were the properties of the antenna that were taken into consideration. The importance of the choice of the antenna for any particular type of indoor environment is also mentioned. In chapter six, the design and fabrication of the monopole antennas used for the experimental measurement is mentioned. The procedure for measurement and the equipment used are also discussed. The results gotten from the experiment are finally analyzed and discussed. In this chapter the effect of walls, floors, doors, ceilings and other obstacles on radio wave propagation will be seen. Finally, chapter seven concludes this thesis work and gives some directions for future work

Adaptive Beamforming and Adaptive Modulation-Assisted Network Performance of Multiuser Detection-Aided FDD and TDD CDMA Systems

The network performance of a frequency division duplex and time division duplex (TDD) code division multiple access (CDMA)-based system is investigated using system parameters similar to those of the Universal Mobile Telecommunication System. The new call blocking and call dropping probabilities, the probability of low-quality access, and the required average transmit power are quantified both with and without adaptive antenna arrays (AAAs), as well as when subjected to shadow fading. In some of the scenarios investigated, the system’s user capacity is doubled with the advent of adaptive antennas. The employment of adaptive modulation techniques in conjunction with AAAs resulted in further significant network capacity gains. This is particularly so in the context of TDD CDMA, where the system’s capacity becomes poor without adaptive antennas and adaptive modulation owing to the high base station (BS) to BS interference inflicted as a consequence of potentially using all time slots in both the uplink and downlink of the emerging wireless Internet. Index Terms—Adaptive beamforming, adaptive modulation, code division multiple access (CDMA) systems, Universal Mobile Telecommunication System Terrestrial Radio Access (UTRA), wireless network performance

Adaptive channel estimation in WCDMA STTD systems

The receiver performance with the use of a space time transmit diversity (STTD) scheme is more susceptible to the accuracy of channel estimate than that without the use of the STTD scheme since the despreading signals suffer from the effect of crosstalk and the transmit power is equally divided into multiple transmit antennas. As a result, the efficiency of channel estimation in the WCDMA STTD system becomes an important issue more than that in the non-STTD system. In this paper, an adaptive channel estimator (ACE) is designed to mitigate the performance degradation due to inaccurate channel estimation. Numerical results show that the performance improvement significantly increases with the use of the proposed ACE, particularly when the channel condition becomes worse

Performance analysis of multi-antenna and multi-user methods for 3G and beyond

Performance of cellular networks has become an issue with forecasted growing public demand for medium and high data rate services. Motivated by these expectations multi-antenna techniques such as transmit diversity (TD), channel-aware scheduling and multiple-input multiple-output (MIMO) transceivers have received a lot of enthusiasm within wireless communications community. We first focus on closed-loop (CL) TD and introduce extended mode 1 and 2 (e-mode 1 and 2) algorithms that are designed based on universal terrestrial radio access (UTRA) frequency division duplex (FDD) CL mode 1 and 2. We derive analytical performance results for e-mode 1 and 2 in terms of signal to noise ratio (SNR) gain, link capacity and bit error probability (BEP). We also consider the effect of feedback errors to the performance of closed-loop system. In the analysis of channel-aware scheduling we focus on on-off scheduling (OOS) where user's feedback consists of only a single bit. Performance results in both downlink and uplink clearly indicate that most of the achievable gain from channel-aware scheduling can be obtained with very scarce channel state information (CSI). Results also show that the design of feedback channel is of great importance because feedback errors may seriously degrade the system performance. The third topic of the thesis concentrates on MIMO techniques that can be implemented in UTRA FDD uplink without major revisions to the current air interface. We show that the UTRA FDD uplink coverage and capacity performance can be boosted by single-input multiple-output (SIMO) and MIMO transceivers. The information MIMO employing parallel multiplexing instead of transmit diversity shows its potential when extremely high user data rates are needed.Solukkoverkkojen suorituskyky on noussut tärkeään rooliin nopeiden datapalveluiden kasvuennusteiden myötä. Näiden kasvuodotusten perusteella moniantennitekniikat kuten lähetysdiversiteetti, kanavan huomioon ottava lähetyksen aikataulutus sekä useaa samanaikaista datavirtaa tukevat lähetinvastaanotinmenetelmät ovat saaneet osakseen paljon kiinnostusta langattoman tietoliikenteen tutkijayhteisössä. Tutkimuksessa keskitytään aluksi suljettua säätöä käyttäviin lähetysdiversiteettimenetelmiin, missä yhteydessä esitellään laajennetut moodien 1 ja 2 algoritmit, jotka on aiemmin kehitetty kolmannen sukupolven WCDMA järjestelmän suljetun säädön moodien 1 ja 2 pohjalta. Laajennetuille moodien 1 ja 2 algoritmeille johdetaan analyyttisiä suorituskykytuloksia käyttäen mittarina signaali-kohinasuhteen parannusta, linkin kapasiteettia sekä bittivirheiden todennäköisyyttä. Myös säätövirheiden vaikutusta järjestelmän suorituskykyyn tarkastellaan. Lähetyksen aikataulutuksen analyysi painottuu kytkettyyn aikataulutukseen, missä käyttäjän säätöinformaatio sisältyy yhteen bittiin. Sekä ylä- että alalinkin suorituskykytulokset osoittavat selvästi, että suurin osa mahdollisesta parannuksesta voidaan saavuttaa hyvin karkeaan kanavatilan informaatioon perustuen. Tulokset osoittavat myös, että säätökanavan suunnittelu on tärkeää, koska säätövirheet voivat vakavasti heikentää järjestelmän suorituskykyä. Kolmannessa aihealueessa keskitytään moniantennitekniikoihin, jotka voidaan toteuttaa WCDMA järjestelmän ylälinkissä ilman perustavanlaatuisia muutoksia nykyiseen ilmarajapintaan. Tutkimuksessa osoitetaan, että ylälinkin peittoa ja kapasiteettia voidaan parantaa tutkituilla moniantennitekniikoilla olipa lähettimessä yksi tai useampia antenneja. Menetelmä, jossa informaatio jaetaan useisiin rinnakkaisiin datavirtoihin sen sijaan että käytettäisiin vain yhtä datavirtaa, osoittautuu erityisen lupaavaksi kun tarvitaan hyvin nopeita tiedonsiirtoyhteyksiä.reviewe

Power control for WCDMA

This project tries to introduce itself in the physical implementations that make possible the denominated third generation mobile technology. As well as to know the technology kind that makes possible, for example, a video-call in real time. During this project, the different phases passed from the election of WCDMA like the access method for UMTS will appear. Its coexistence with previous network GSM will be analyzed, where the compatibility between systems has been one of the most important aspects in the development of WCDMA, the involved standardization organisms in the process, as well as the different protocols that make the mobile communications within a network UTRAN possible. Special emphasis during the study of the great contribution that has offered WCDMA with respect to the control of power of the existing signals will be made. The future lines that are considered in the present, and other comment that already are in their last phase of development in the field of the mobile technology. UMTS through WCDMA can be summarized like a revolution of the air interface accompanied by a revolution in the network of their architecture