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Langaton tiedonsiirtoteknologia on eri muodoissaan olennainen osa nykyaikaista yhteiskuntaa. Langattomuuden tarjoamat edut ovat tuoneet nämä teknologiat myös osaksi teollisuusympäristöä esimerkiksi erilaisten langattomien anturiverkkojen (WSN, wireless sensor network) muodossa. Anturiverkkojen lisäksi langatonta tiedonsiirtoa voi olla mahdollista hyödyntää tarjoamaan helppo pääsy kentältä teollisuuslaitosta ohjaaviin järjestelmiin käyttäen WLAN (Wireless Local Area Network)-tekniikkaa. Tässä työssä on tavoitteena selvittää, kuinka langatonta tiedonsiirtoa voitaisiin hyödyntää huoltovarmuuskriittisessä voimalaitosympäristössä ja minkälaisia vaatimuksia kyseinen ympäristö asettaa tekniikalle. Oleellisimmat vaatimukset liittyvät tiedonsiirron tekniseen toimivuuteen, langattomien järjestelmien tietoturvallisuuteen sekä käytettävyyteen. Työssä perehdytään ensin hieman IEEE 802.11- ja IEEE 802.15.4-standardeihin pohjautuvien verkkojen toimintaan ja selvitetään mitä mahdollisia etuja ja ongelmia langattomat verkot voivat tuoda voimalaitoskäyttöön. Lisäksi esitellään muutamia mahdollisia sovelluksia langattomille verkoille perustuen edellä mainittuihin standardeihin. Työn puitteissa tehdään myös mittauksia voimalaitosympäristössä käyttäen WLAN-laitteita. Näillä mittauksilla on tarkoitus selvittää tiedonsiirron toimivuus haastavassa ympäristössä sekä 2,4GHz- että 5GHz-taajuusalueilla. Mittausten perusteella pyritään selvittämään, onko langaton tiedonsiirto ylipäätään teknisesti hyödynnettävissä voimalaitoksella., Different types of wireless networks are an integral part of life in a modern society. The potential benefits of wireless communication have brought these technologies to the industrial environment for example in the form of wireless sensor networks (WSNs). A WLAN (Wireless Local Area Network)-connection could also be used to provide a wireless connection to industrial control systems from the field. The goal of this thesis is to identify possible uses for wireless networks in a power plant that is part of the nation’s critical infrastructure. The aim is also to identify any special requirements that this environment might pose for the utilization of wireless networks, technical or otherwise. The most important requirements are associated with the technical reliability of wireless data transfer, security and usability. This thesis takes a look at the IEEE 802.11 and IEEE 802.15.4 standards and the possible benefits and problems associated with utilization of wireless networks. Also some possible applications for wireless networks based on these standards are presented. Measurements in the field are also conducted using WLAN-devices on the 2,4GHz and 5GHz-bands. The aim of these measurements is test the functioning of wireless data transfer in a challenging environment and to determine overall feasibility of using wireless networks in a power plant environment.

Recent technological developments in wireless and sensor networks have led to a paradigm shift in interacting with everyday objects, which nurtured the concept of Internet of Things (IoT). However, low-powered nature of IoT devices generally becomes a hindrance that makes them vulnerable to a wide array of attacks. Among these, the emergence of rogue devices is quickly becoming a major security concern. Rogue devices are malicious in nature which typically execute different kinds of cyberattacks by exploiting the weaknesses of access control schemes in IoT environments. Therefore, access control is one of the crucial aspects of an IoT ecosystem that defines an entry point for a device or a user in the network. This paper investigates this issue and presents an access control scheme by integrating an IoT network with blockchain technology, thereby arguing to replace the traditional centralized IoT-server architecture with a decentralized one. The blockchain is used with smart contracts to establish a secure platform for device registration. Due to this reason, the IoT devices are first required to register themselves and access the network via contracts thereafter. Moreover, the contracts host a device registry, the access control list, to grant or deny access to devices. This allows the proposed scheme to authorize registered devices only and block unregistered ones, which facilitates the mitigation of rogue devices. To demonstrate the feasibility and improvements of the proposed scheme, security analysis along with in-depth performance evaluation are conducted, where the obtained results indicate its applicability. A case study is also formulated with a comparative analysis that confirms the superior performance of the proposed scheme for low-powered IoT systems.

Cellular connectivity for drones comes with a wide set of challenges as well as opportunities. Communication of cellular-connected drones is influenced by 3-dimensional mobility and line-of-sight channel characteristics which results in higher number of handovers with increasing altitude. Our cell planning simulations in coexistence of aerial and terrestrial users indicate that the severe interference from drones to base stations is a major challenge for uplink communications of terrestrial users. Here, we first present the major challenges in co-existence of terrestrial and drone communications by considering real geographical network data for Stockholm. Then, we derive analytical models for the key performance indicators (KPIs), including communications delay and interference over cellular networks, and formulate the handover and radio resource management (H-RRM) optimization problem. Afterwards, we transform this problem into a machine learning problem, and propose a deep reinforcement learning solution to solve HRRM problem. Finally, using simulation results, we present how the speed and altitude of drones, and the tolerable level of interference, shape the optimal H-RRM policy in the network. Especially, the heat-maps of handover decisions for different altitudes/speeds of drones have been presented, which promote a revision of the legacy handover schemes and boundaries of cells in the sky., QC 20210913

In the past few years, Linux container implementation Docker, which also provides the means to distribute, control, manage and orchestrate the containers, has been increasingly adopted in software development and the cloud. Docker provides an easy way to deploy containers and take the benefits of them, and thus it might be a beneficial software deployment approach for the industrial IoT gateways. However, the applicability of Docker has not been investigated enough in resource-constrained devices, such as the industrial IoT gateways. Thus, the aim of this thesis was to assess if Docker is applicable in industrial IoT gateways. The applicability of Docker was assessed in terms of its security, performance and resource usage, lifecycle management and deployment, and engineering work. Docker was found to increase the potential attack surface, but with appropriate countermeasures and configurations to provide a secure environment. Docker was found to cause non-negligible performance degradation on CPU, disk, and network. Thus, if the application is desired to run at its peak performance, Docker is not the recommendable deployment approach. Docker was found to consume a negligible amount of disk space, but non-negligible amount of memory, thus making it unsuitable for devices with less than 1GB of memory. Docker was found to provide the necessary features needed for lifecycle management and deployment, but its successful adoption might require additional tools that the Docker Community Edition does not provide. However, additional tools can be bought from Docker. Docker was found to increase the required engineering work as additional components have to be configured. However, Docker has made these additional engineering tasks as easy as possible and provides extensive guides on how to perform the tasks in a recommendable way. In conclusion, it was found that Docker is applicable for industrial IoT gateways with certain limitations and that a case by case consideration w, Viime vuosina Linux-konttiteknologian toteutus Docker, joka tarjoaa myös tavan levittää, kontrolloida, hallita ja orkestroida kontteja, on enenevässä määrin otettu käyttöön ohjelmistokehityksessä ja pilvessä. Docker tarjoaa helpon tavan käyttöönottaa kontteja ja hyödyntää niitä, ja sen takia se on mahdollisesti hyödyllinen tapa suorittaa ohjelmistoja teollisen internetin yhdyskäytävissä. Dockeria ei ole kuitenkaan tutkittu riittävästi resurssirajoitteisissa laitteissa, kuten teollisen internetin yhdyskäytävissä. Tästä syystä, tämän diplomityön tarkoituksena oli arvioida, soveltuuko Docker teollisen internetin yhdyskäytäviin. Soveltuvuutta arvioitiin tietoturvan, suorituskyvyn ja resurssien käytön, elinkaaren hallinnan ja käyttöönoton, sekä tarvittavan insinöörityön pohjalta. Dockerin todettiin lisäävän potentiaalista hyökkäysrajapintaa, mutta sopivilla vastatoimenpiteillä ja konfiguraatioilla sen todettiin olevan tietoturvallinen ohjelmistojen suoritusympäristö. Dockerin havaittiin aiheuttavan huomattavaa prosessorin, kiintolevyn ja verkon suorituskyvyn heikkenemistä. Tästä syystä ei ole suositeltavaa käyttää Dockeria ohjelmistojen suoritusympäristönä, jos tavoitellaan maksimaalista suorituskykyä. Dockerin havaittiin käyttävän merkityksettömän määrän tallennustilaa, mutta huomattavan määrän muistia. Tästä syystä Docker ei sovellu laitteille, joissa on alle 1Gt muistia. Dockerin todettiin tarjoavan tarvittavat ominaisuudet elinkaaren hallintaan ja käyttöönottoon. Toisaalta Dockerin onnistuneeseen käyttöön saatetaan tarvita lisätyökaluja, joita Dockerin yhteisöversio ei tarjoa. Näitä työkaluja pystyy kuitenkin ostamaan Dockerilta. Dockerin todettiin lisäävän tarvittavaa insinöörityötä, koska siinä on enemmän komponentteja, jotka pitää konfiguroida. Tarvittavat insinöörityöt on kuitenkin tehty mahdollisimman helpoiksi ja tarjolla on kattavia oppaita siitä, miten asiat tehdään suositeltavalla tavalla. Johtopäätöksenä voidaan todeta, että tietyin rajoittein Docker sovelt

Ambient Backscatter is a communications method for batteryless, carrier-powered radio devices which harvest the needed energy from ambient sources and send their information by backscattering the ambient radio signals. An ambient backscatter device sends data bit by bit by either backscattering or not backscattering the received carrier wave. This work studies the operation of an ambient backscatter communication system consisting of a transmitter, a number of ambient backscatter devices and a receiver by simulating it in MATLAB. This thesis aims to answer the research questions: when it is better to use either passive or active ambient backscatter devices and what factors primarily affect the maximum data rate, communication range and susceptibility to interference of the devices. A definite answer to the research questions could not be given, but the thesis results show that active aBS- devices have potential of reaching the same performance figures as passive ones in terms of achievable range.

Execution of real-time software is uncertain on PCs, due to the nature of the design of the PC. The test results of this thesis show that optimizing the real-time Linux kernel parameters is beneficial for the performance of an open source LTE eNB PC software OpenAirInterface. An introduction of the relevant parts of the LTE standard is provided, along with an explanation of Linux task scheduling. This makes testing of performance critical software necessary. Multiple parameters were tested, and the results of the most beneficial ones are introduced in the end of this thesis., Tämä diplomityö keskittyy avoimen lähdekoodin OpenAirInterface ohjelmistoon. Kyseinen ohjelmisto toimii LTE eNB:na tai UE:na ja sitä käytetään tietokoneissa, joissa on Linux pohjainen käyttöjärjestelmä. Ohjelmiston suorituskyky vaihtelee, sillä Linux ei ole reaaliaikainen järjestelmä. Suorituskykyyn vaikuttaa käyttöjärjestelmän ajastuksista vastaava osa. Tämän osan suorituskykyyn voi vaikuttaa sen parametreja muuttamalla. Tämä työ sisältää tiivistettynä LTE-järjestelmien perusteet, miten Linux käyttöjärjestelmässä oleva ohjelmisto toimii, sekä miten ajastuksista vastaavan käyttöjärjestelmän parametrien muutokset vaikuttavat ohjelmistojen suorituskykyyn. Tuloksista nähdään, että parametrien muuttaminen vaikuttaa OpenAirInterface ohjelmiston suorituskykyyn, ja niiden vaikutuksen mittaamisesta ja muuttamisesta on hyötyä sekä OpenAirInterfacen käytössä, että muiden reaaliaikaisten ohjelmistojen käytössä.

The Fifth Generation (5G) Ultra Reliable Low Latency Communication (URLLC) is envisioned to be one of the most promising drivers for many of the emerging use cases, including industrial automation. In this study, a factory scenario with mobile robots connected via a 5G network with two indoor cells is analyzed. The aim of this study is to analyze how URLLC requirements can be met with the aid of multi-Transmission Reception Points (TRxPs), for a scenario, which is interference limited. By means of simulations, it is shown that availability and reliability can be significantly improved by using multi-TRxPs, especially when the network becomes more loaded. In fact, optimized usage of multi-TRxPs can allow the factory to support a higher capacity while still meeting URLLC requirements. The results indicate that the choice of the number of TRxPs, which simultaneously transmit to a UE, and the locations of the TRxPs around the factory, is of high importance. A poor choice could worsen interference and lower reliability. The general conclusion is that it is best to deploy many TRxPs, but have the UE receive data from only one or maximum two at a time. Additionally, the TRxPs should be distributed enough in the factory to be able to properly improve the received signal, but far enough from the TRxPs of the other cell to limit the additional interference caused.

Digitalization caused a considerable increase in the use of industrial automation applications. Industrial automation applications use real-time traffic with strict requirements of connection of tens of devices, high-reliability, determinism, low-latency, and synchronization. The current solutions meeting these requirements are wired technologies. However, there is a need for wireless technologies for mobility,less complexity, and quick deployment. There are many studies on cellular technologies for industrial automation scenarios with strict reliability and latency requirements, but not many developments for wireless communications over unlicensed bands. Wireless Fidelity (Wi-Fi) is a commonly used and preferred technology in factory automation since it is supported by many applications and operates on a license free-band. However, there is still room for improving Wi-Fi systems performance for low-latency and high-reliable communication requirements in industrial automation use cases. There are various limitations in the current Wi-Fi system restraining the deployment for time-critical operations. For meeting the strict timing requirements of low delay and jitter in industrial automation applications, Quality of Service (QoS)in Wi-Fi needs to be improved. In this thesis, a new access category in Medium Access Control (MAC) layer for industrial automation applications is proposed.The performance improvement is analyzed with simulations, and a jitter definition for a Wi-Fi system is studied. Then, a fixed Modulation and Coding (MCS) link adaptation method and bounded delay is implemented for time-critical traffic in the simulation cases to observe performance changes. Finally, it is shown that the new access category with no backoff time can decrease the delay and jitter of time-critical applications. The improvements in Wi-Fi QoS are shown in comparison with the current standard, and additional enhancements about using a fixed modulation and coding scheme and imple

The impact of Internet of Things on business, society, manufacturing, industries and supply chain is significant. Modern technologies enable us to monitor and control things in new ways and in real-time. In addition, connecting appliances to work together has become easier than before. Although, development has only begun in the world of IoT as current implementations cover only fraction of the smart solutions visioned by future researchers. Consuming data produced by sensors connected to the Internet creates an opportunity to implement various kinds of solutions. In general, use cases consist of same kind of software components. Similarity of components forms a question: Could a general concept be designed and used as a basis to kickstart development of IoT application? This thesis proposes a general concept to advise IoT related software development and introduces a design and implementation steps of an example IoT-solution. Estimating business value of an IoT-solution might require piloting. Hence, agile software development aims to reduce cost of experimenting in the field of IoT. Furthermore, utilizing a template might also help to organize work load on any project. We begin this thesis with a background study on history of IoT, protocols and standards. Applications and trends are also discussed. Relevant communication, authentication and database technologies are reviewed. Concept components are identified by conducting case study on previous implementations and resulted concept applied to structure a system architecture, which includes a traditional REST API endpoints and modern socket connection to support real-time data streaming. Example implementation is developed using Node.js to produce software modules and test the designed concept., Esineiden internetin (eng. Internet of Things, IoT) vaikutus liike-elämään, yhteiskuntaan, valmistamiseen, teollisuuteen ja toimitusketjuun on merkittävä. Nykyteknologian ansiosta voimme seurata ja hallita asioita uudella tavalla, reaaliajassa sekä eri laitteiden yhteiskäyttö on helpottunut huomattavasti. Olemassa olevat älykkäät ratkaisut eivät kuitenkaan kata kuin murto-osan tulevaisuuden tutkijoiden visioimista sovelluksista, joten IoT-ratkaisujen kehitys on vasta alkuvaiheessa. Sensorien tuottaman datan käyttö internetin yli luo mahdollisuuden monille eri käyttötarkoituksille. Ratkaisut koostuvat usein samankaltaisista komponenteista. Tämä herättääkin kysymyksen: olisiko mahdollista suunnitella yleinen konsepti, jota voitaisiin käyttää alustana monille eri IoT-ratkaisuille. Tässä diplomityössä esitetään yleinen konsepti, jota voidaan käyttää IoT-ohjelmistokehityksen apuna. Työ sisältää myös esimerkki-IoT -ratkaisun suunnittelun ja toteutuksen vaiheet. Usein IoT-ratkaisujen luoman hyödyn ja liiketoiminnallisen arvon arviointi vaatii pilotointia. Pyrkimyksenä onkin ketterä ja kustannustehokas ohjelmistokehitys. Tätä voidaan edesauttaa valmiilla komponenteilla ja ohjelmisto-rungolla, jolloin resurssisuunnittelukin on helpompaa. Diplomityö alkaa taustatutkimuksesta, joka kattaa IoT:n historian, protokollat ja standardit sekä sovellukset ja trendit. Tarkastelussa käydään läpi myös tähän liittyvät yleisimmät kommunikaatio-, autentikointi- ja tietokantateknologiat. Konseptin komponentit tunnistetaan aiempien toteutusten osalta tapaustutkimusmetodin keinoin. Tunnistettujen komponenttien perusteella suunnitellaan järjestelmäarkkitehtuuri, joka sisältää perinteisen REST-käsitteen mukaiset ohjelmistorajapinnat sekä modernin tavan välittää tietoa reaaliajassa. Arkkitehtuurin pohjalta kehitetyn Node.js-pohjaisen ohjelmiston tarkoitus on luoda uudelleenkäytettävät komponentit sekä testata suunnitellun konseptin käyttöä.

Global Satellite Navigation System (GNSS) receivers use the time signals broadcast by the satellites for computing position fix and the time offset from the highly accurate satellite clocks. The receiver calculates the range between the receiver and the satellite using time of arrival (TOA) method and applies the principle of trilateration to calculate the position fix and time offset after acquiring the information from at least 4 different satellites. In this thesis work, benefits of using dual feed antenna to improve the timing accuracy of the receiver clock in urban canyons and indoor environments are analyzed. Dual feed antenna is capable of processing information from Line of Sight (LOS) signals received directly from the satellites as well as the reflected signals from the surfaces such as metallic objects, building edges and so on. These signals are fed separately to two different receivers, which compute the position and receiver clock offset, respectively. The computed time offset from both the receivers are compared and analyzed in different location environments with weak or insufficient GNSS signal strengths. Additionally, the benefits of providing assisted GNSS (AGNSS) data to GNSS receivers to reduce the time to first fix (TTFF) in such locations are analyzed. The use of assist data allows the receiver to obtain the necessary satellite information alternatively without having to download those information from the GNSS signals. This reduces receiver’s time to make position fix significantly in challenging locations with insufficient and weak signal strengths. The TTFF with and without the use of AGNSS data are compared.

The telecommunication industry is accelerating towards a Cloud-native All-IT infrastructure with flat architecture, to meet the requirements in the era of the fifth generation (5G) of mobile communication systems. Various hardware-based network functions are to be virtualized, operated by software, and distributed into Cloud resources as Virtual Network Functions (VNF). However, this transformation brings additional technical challenges. Performance unpredictability of VNFs can be considered as one of the most critical among all, and it is mainly due to the shared resources pooling feature of Cloud Computing. The virtualization layer, in between the Virtual Machines (VM) and host machine, tries to implement some fairness in scheduling the shared resources but there might be delays in availability of resources, which will degrade the performance of any waiting VMs. Continuous monitoring of the resources utilized by the VMs is thus essential in ensuring their individual performances and the performance of any constituted VNF(s). Monitoring the CPU resource utilization can be considered as most important since the other resources are not directly impacted by the virtualization layer. A VNF’s total CPU utilization is the sum of the total CPU utilized by each VM that constitutes it. For every CPU utilized by a VM, the virtualization layer needs to support and schedule that usage and by doing so, utilizes some CPU itself which needs to be accounted to the VM. Since the virtualization layer resides in the host machine, monitoring and accounting for the CPU utilized by the virtualization layer on behalf of any VM would require privileged access to the host machine which is usually not granted by most Cloud service providers; making it impossible to calculate any VM’s total CPU utilization. This thesis’s study presents a solution to determine a VNF’s total CPU utilization without the need for any privileged access to the host machine. Applications running inside a VNF have s

We present a generic approximation of the packet error rate (PER) function of uncoded schemes in the AWGN channel using extreme value theory (EVT). The PER function can assume both the exponential and the Gaussian Q-function bit error rate (BER) forms. The EVT approach leads us to a best closed-form approximation, in terms of accuracy and computational efficiency, of the average PER in block-fading channels. The numerical analysis shows that the approximation holds tight for any value of SNR and packet length whereas the earlier studies approximate the average PER only at asymptotic SNRs and packet lengths.

The software testing process is one of the most important phases during software development to check that the developed software product meets its specified specifications/requirements. This is especially true for the software products used in the health-industry. Supported browsers can also be documented into the requirements. Thus browser compatibility testing needs to be considered, especially while performing testing on web-based software products. Browser compatibility testing is performed to test the software product with different kinds of combinations, including browser types and their different versions. This ensures that developed web-based products are working properly with these different combinations during the software development process before releasing to market. The problem with browser compatibility testing is that it is not easy to perform tests on all possible and supported browser combinations manually, without using any tools. The goal of this study is to evaluate available browser compatibility tools and use the chosen tool during the software development process to get rapid feedback about the developed product, by performing browser compatibility test cases automatically. Test cases need to be automated to get the benefits of the tools. The results of the study after the evaluation and usage of the selected tool was comprehensive enough to fix the problems during the software development process.

Coordinated MultiPoint leverages coordination between different nodes in the network to jointly processing signals, increasing the transmission quality. Nevertheless, the tight requirements that Coordinated MultiPoint imposes over the backhaul claim for a holistic redefinition of the cellular networks architecture. Cloud Radio Access Network emerges as a candidate for such redefinition, enabling the implementation of advanced coordination schemes like Coordinated MultiPoint. Very few field trials of Coordianted MultiPoint have been carried out, even less making use of a Cloud Radio Access Network architecture and none of them in an indoor environment. As indoor scenarios are increasingly playing an important role in cellular networks, a field trial of Coordinated MultiPoint in such an environment is of the utmost importance. This Master`s Thesis aims at the evaluation of the downlink throughput enhancement that the implementation of Coordinated MultiPoint Joint Transmission brings to the users of a Cloud Radio Access Network based indoor cellular network, under different Modulations and Coding Schemes. A Long Term Evolution cellular network is deployed over a Cloud Radio Access Network architecture by means of a Software Defined Radio platform. A baseline scenario featuring no coordination between nodes and another scenario implementing Coordinated MultiPoint Joint Transmission are deployed in order to be compared in terms of downlink throughput. The obtained results show that, for the vast majority of Modulation and Coding Schemes applied when Coordinated MultiPoint Joint Transmission is enabled, the downlink throughput of cell edge users is improved, as opposed to cell centre users whose throughput gets negatively affected.

Telecommunications network operators are shifting from circuit switched backhaul technologies into packet switched networks to save costs with increasing traffic loads. Frequency synchronization was inherently provided by the circuit switched network, but has to be provided by other means in packet switched networks. One solution is Precision Time Protocol (PTP), defined in IEEE standard 1588, which can be used to create a master-slave synchronization strategy to a network. Synchronization quality is an essential factor when using any synchronization technology. Packet synchronization quality requirements in different situations are defined in ITU-T recommendation G.8261. The objective of this thesis is to create test automation for ITU-T recommendation G.8261 Appendix VI performance test cases 12 through 17 for Precision Time Protocol. Hypothesis is that this automation will make testing more effective than if testing was done manually, allowing testing of more products in a smaller time frame. Automated test system was planned and implemented with various measurement and impairment devices, and testing software to utilize them and to generate results. As a result, PTP synchronization quality testing efficiency was increased by over 20% while reducing the possibility for human errors., Verkko-operaattorit vaihtavat matkapuhelinverkoissa käyttämiään tekniikoita piirikytkentäisistä pakettikytkentäisiin säästääkseen kustannuksia kasvavien liikennemäärien kanssa. Piirikytkentäisissä verkoissa taajuussynkronointi leviää verkkoteknologian myötä automaattisesti koko verkkoon, mutta pakettikytkentäisissä verkoissa se täytyy tuottaa muilla tavoin. Yksi ratkaisu ongelmaan on Precision Time Protocol (PTP), joka on määritelty IEEE standardissa 1588, ja jolla voidaan luoda verkkoon isäntä–renki -synkronointistrategia. Synkronoinnin laatu on keskeinen tekijä kaikissa synkronointiteknologioissa. Pakettisynkronoinnin laatuvaatimuksia eri tapauksissa on määritelty ITU-T suosituksessa G.8261. Tämän diplomityön tavoitteena on luoda testausautomaatio ITU-T suosituksen G.8261 liitteen VI suorituskykytesteille 12–17 käyttäen PTP:tä. Hypoteesina on, että automaation avulla testauksesta tulee tehokkaampaa, kuin jos samat testit suoritettaisiin manuaalisesti. Näin entistä useammat tuotteet saataisiin testattua entistä lyhyemmässä ajassa. Automatisoitu testausjärjestelmä suunniteltiin ja toteutettiin käyttäen valikoimaa erilaisia mittauslaitteita ja verkkoemulaattoreita, sekä näiden laitteiden hallintaan kehitettyä testausohjelmistoa. Lopputuloksena PTP-synkronointitestauksen nopeus parani yli 20 prosenttia ja inhimillisten virheiden mahdollisuus väheni.

Wireless technology in our daily lives is giving a way to more and more inter connected devices. More increasingly innovative applications are being developed for daily usage ranging from simple sensing devices to autonomous robots. With all these extra additions, the burden on wireless technologies such as WLAN and 3G/4G/LTE is leading to the development of new network architectures and protocols. Teleoperation of remote devices are finding their way into common places using those technologies. In this thesis work a teleoperation software was developed to use wireless serial devices to control a remote robot over the network and perform autonomous tasks under the supervision of an operator. The robot is an indoor wheeled mobile robot and operator’s device is a computer, both running on Windows OS. This system is similar to a Wireless Sensor Networks with actuators and sensors being on the robot device while the control brain is on a remote computer. The full system has several components like graphics for robot parameters, settings for communications, modes of operations for operator and robot’s own localization and safety tasks. Field tests validated the full functionality of the system but in four out of nine trials failure of wireless devices caused complete system paralysis. An autonomous trajectory following operation was implemented to study the effects of packet loss in communication, it was found that control was reliable even with 26 percent drop. With a linear driving test it was also observed that robot’s free moving wheel was causing an orientation error adding an extra 0.06 degree when moving backwards. A continuous transmission of data packets in the network ensures reliability in the system, this is very important from operator’s perspective.

Cloud Radio Access Network (C-RAN) development is one branch of fifth generation (5G) mobile network research. In C-RAN, most processing related to network operation is moved from the base stations to data center servers, thus providing flexibility and cost savings. The Aalto Radio Framework (ARF) software implements part of the Long Term Evolution (LTE) specification. It includes a partial implementation of a base station that implements the air interface. In LTE, a base station uses the S1 interface to communicate with the network core. The control plane of this S1 interface uses the S1 Application Protocol (S1AP). In this work, the S1AP is fully implemented as an independent module, which is then integrated into the ARF software. The S1AP is specified using Abstract Syntax Notation One (ASN.1). To implement a protocol specified with ASN.1, an ASN.1 compiler is used to generate encoder and decoder code from the abstract syntax. In this work, the open source asn1c compiler was used. However, the asn1c compiler does not support ASN.1 information object classes. This causes an incompatibility between asn1c and the S1AP abstract syntax, and workarounds had to be developed. This involved modifying part of the S1AP abstract syntax without altering the original meaning, and writing scripts to generate code from asn1c incompatible parts of the resulting abstract syntax. An (API) was also developed to provide a much easier to use interface to use S1AP without requiring knowledge of ASN.1. Use of this API was integrated into ARF to enable and facilitate further development into the S1 interface logic., Radioverkon pilvitoteutuksen tutkimus on osa viidennen sukupolven mobiiliverkkojen tutkimusta. Radioverkon pilvitoteutuksessa suurin osa tukiasemien verkon toimintaan liittyvästä prosessoinnista pyritään siirtämään datakeskuksiin. Näin saavutetaan joustavuutta verkon toteutukseen ja kustannukset laskevat. Aalto Radio Framework (ARF) on ohjelmisto, joka toteuttaa osan LTE verkon toiminnasta. Se sisältää osittaisen toteutuksen tukiasemasta joka toteuttaa radio rajapinnan. LTE verkossa tukiasema keskustelee verkon ytimen kanssa S1 rajapinnan avulla. Tämän rajapinnan kontrollitaso käyttää S1AP protokollaa. Tässä diplomityössä toteutetaan kyseinen protokolla kokonaisuudessaan ja integroidaan se osaksi ARF ohjelmistoa. S1AP protokolla on määritelty Abstract Syntax Notation One (ASN.1) notaation avulla. ASN.1:n avulla määritelty protokolla voidaan toteuttaa ASN.1 kääntäjän avustuksella. ASN.1 kääntäjä muuntaa abstraktin notaation ohjelmakoodiksi, joka koodaa ja dekoodaa protokollan viestejä. Tässä diplomityössä on käytetty avoimen lähdekoodin ASN.1 kääntäjää nimeltä asn1c. Asn1c ei kuitenkaan täysin tue ASN.1:n informaatio luokka konseptia. Tämä aiheuttaa yhteensopimattomuuden S1AP:n abstraktin syntaksin ja asn1c kääntäjän välille. Tämän ongelman ratkaisemiseksi S1AP:n abstraktia syntaksia on muokattu asn1c yhteensopivampaan muotoon siten, ettei syntaksin alkuperäinen merkitys kuitenkaan muutu. Lisäksi on toteutettu skriptejä jotka jäsentävät osan tästä abstraktista syntaksista ja tuottavat ohjelmakoodia sen perusteella. Lisäksi tässä työssä toteutettiin uusi ohjelmisto rajapinta, joka tarjoaa helppokäyttöisen käyttöliittymän S1AP:n käyttämiseen. Tämä rajapinta ei myöskään vaadi ASN.1:n tuntemusta. Lopuksi S1AP toteutus integroitiin ARF ohjelmistoon, joka mahdollistaa ja helpottaa S1 rajapinnan toiminnallisen logiikan jatkokehitystä.

In Long Term Evolution (LTE) uplink transmission, a User Equipment (UE) must be time-synchronized before normal data transmission. So that a Physical Random Access Channel (PRACH) becomes a crucial factor for LTE access scheme since it is the base on which the Random Access Channel (RACH) is implemented. In this project, a PRACH module for TD-LTE base station system using software defined radio has been implemented. The System follows the release 8 of LTE-UMTS specifications. During the development, a scenario with simple uplink transmission between one UE and one eNodeB has be considered. The UE is able to generate one PRACH sequence and its baseband signal at a time. In the other hand, The eNodeB is able to generate the 64 PRACH sequences available per LTE-cell, process the baseband signal received from the UE and detect the PRACH sequence transmitted in approximately 1ms., En Long Term Evolution (LTE), en la transmisión en enlace ascendiente, un equipo de usuario (UE) debe estar sincronizado en tiempo antes de la transmisión normal de datos. Por consiguiente, un Physical Random Access Channel (PRACH) se convierte en un factor crucial para el esquema de acceso LTE ya que es la base sobre la que se implementa el Random Access Channel (RACH). En este proyecto, se ha implementado el módulo PRACH para una estación base TD-LTE utilizando radio definida por software. El sistema sigue las especificaciones del LTE-UMTS, version 8. Durante el desarrollo, se ha considerado un escenario en el que tenemos una simple transmisión en enlace ascendiente entre un UE y un eNodeB. El UE es capaz de generar solo un PRACH sequence y su baseband signal cada vez. El eNodeB por el otro lado es capaz de generar los 64 PRACH sequences disponibles para cada LTE-cell, procesar el baseband signal recibido y encontrar en aproximadamente 1 ms el PRACH sequence transmitido., En Long term Evolution, en la transmissió en enllaç ascendent, un equip d'usuari (UE) ha d'estar sincronitzat en temps abans de la transmissió normal de dades. Per conseqüent, un Physical Random Access Channel (PRACH) es torna un factor crucial per a l'esquema d'access LTE ja que es la base sobre la que s' implementa el Random Access Channel (RACH). En aquest project, s'ha implementat el mòdul PRACH per a una estació base TD-LTE utilitzant ràdio definida per software. El sistema segueix les especificacions del LTE-UMTS, versió 8. Durant el desenvolupament, s'ha considerat un escenari en el que tenim una simple transmissió en enllaç ascendent entre un UE y un eNodeB. UE és capaç de generar només un PRACH sequence i el seu baseband signal cada cop. L'eNodeB per la seva part es capaç de generar els 64 PRACH sequences disponibles per a cada LTE-cell, processar el baseband signal rebut i trobar en aproximadament 1 ms el PRACH sequence transmès.

Low data rate wireless networks can be deployed for physical intrusion detection and localization purposes. The intrusion of a physical object (or human) will disrupt the radio frequency magnetic field, and can be detected by observing the change of radio attenuation. This gives the basis for the radio tomographic imaging technology which has been recently developed for passively monitoring and tracking objects. Due to noise and the lack of knowledge about the number and the sizes of intruding objects, multi-object intrusion detection and localization is a challenging issue. This article proposes an extended VB-GMM (i.e. variational Bayesian Gaussian mixture model) algorithm in treating this problem. The extended VBGMM algorithm applies a Gaussian mixture model to model the changed radio attenuation in a monitored field due to the intrusion of an unknown number of objects, and uses a modified version of the variational Bayesian approach for model estimation. Real world data from both outdoor and indoor experiments (using the radio tomographic imaging technology) have been used to verify the high accuracy and the robustness of the proposed multi-object localization algorithm.

This thesis proposes a Bluetooth Low Energy (BLE) based payment solution for public transportation. The thesis first reviews some of the ‘Mobile payment solutions´. Traditionally, these services have revolved around technologies like Barcodes, Quick Response (QR) codes, Short Messaging Services (SMS) etc. However, with the advent of smartphones equipped with Bluetooth controllers and security chips, a number of innovative payment services are being studied. Furthermore, this thesis also presents the necessary background to understand the BLE technology. Based on BLE technology, BLE based ticketing protocols are presented. An emphasis on Public transport agency is made. To accomplish the task of designing these protocols, Generic Attribute Profile (GATT) system is extensively studied. GATT defines the concepts of services and profiles into the BLE architecture. Profiles like alert notification, proximity and blood pressure are already defined in the BLE specification. Any new profiles created will be put on top of GATT and are known as Custom Profiles. There are Bluetooth controllers manufactured by Nordic semiconductor which is used as reference in designing these protocols. However complete implementation of the system is not performed in this work. A model with necessary protocols is only presented here. This work can also be implemented on various Bluetooth manufacturing controllers.

In today’s internet oriented world, the growth in mobile or cellular data traffic is enormous and the trend is going to continue for years to come. From past few years, the uplink data traffic has been of much importance because of the rise in social networking, video-conferencing, web-browsing etc. Therefore, uplink cell capacity and user experience are the major factors that the operators need to focus on. In uplink, users are not orthogonal to each other. Therefore, it results in interference when multiple users transmit simultaneously. That means to say, in uplink, shared resource is the amount of interference within the cell. Power control is a very important aspect in uplink to control the transmission power of UE’s and thus the resulting interference. In High Speed Uplink Packet Access (HSUPA), a feature called ‘Dynamic Block error rate target selection’ is introduced to control the uplink interference. This feature distinguishes the users into different traffic types based on their bit rate, frame rate and block error rate. Depending on the traffic types, different ideal BLER (Block error rate) targets are used to calculate the power with which the UE has to transmit in the next transmission period so as to introduce minimum interference. This thesis is focused on studying the ‘Dynamic BLER’ feature and then implementing different outer loop power control algorithms related to the feature. Simulations are done for various scenarios (low traffic, moderate traffic, high traffic) within the cell and the gain achieved in terms of cell throughput from this feature is verified through results for all the scenarios.

Full contact sports are inherently dangerous as they involve tough collisions between players. Wireless and sensing technologies have the potential to reduce the risk of severe injuries in athletes by alarming the harshness of each collision between players to a medical team that can deal with this issue instantly, instead of allowing this hit to develop to a serious injury. Ice-Hockey is used as the basis of the experiment in this Master Thesis, since it is the highest contributor to brain injuries in sports and a source of devastating chest injuries. In order to achieve the goal of proposing and evaluating a sport safety system that can monitor and alarm the collisions between players to a medical team, several important questions were put to define the road-map of the research. Initially, a survey on the state-of-the-art sport safety systems has been made. The result of this survey shows that there is only one commercially available system: Head Impact Telemetry (HIT). Then, based on the study of HIT and its related products, several justified system requirements have been listed. Add to that, the applicable wireless and sensing technologies were benchmarked against the developed system requirements. This benchmarking resulted in selecting accelerometers and Bluetooth Low Energy (BLE) for the proposed system. In addition, a theoretical evaluation was made to the proposed system to find the Bit Error Rate (BER), Packet Error Rate (PER), average packet transmissions, average packet delay and packet loss percentage in AWGN, Rayleigh and Rician channels. The system evaluation results show that the proposed system with limited transmissions performs better than the system with infinite transmission attempts in both cases: no interfering users and one interfering user, over the stated channels. The limited transmission attempts system gives lower packet delay and less number of packet re-transmissions. However, this limited transmission attempts system introduces packe