The total number of mobile subscriptions has been announced to reach 6 billion in the market, of which 4 billion are individual users. The rest of the people on earth are potential subscribers that mainly live in rural areas lacking mobile connectivity today. Many of these users do not have access to electricity and have 6 U.S. dollar per month (USD/month) of average revenue per person.   Referring to the year 2007, the telecommunication industry had a contribution of 0.6 percent of direct global carbon dioxide (CO2) or 0.4 percent of global carbon dioxide equivalent (CO2e). From 2007 to 2009, the number of off-grid radio base stations located in rural areas went up from 350,000 to 500,000. Nearly all of these sites use diesel generators and large amounts of fossil fuels during the operational stage. In addition the grid sites with diesel back-up were about 0.5 million in 2009. The financial and environmental consequences of the life cycle impact of the diesel fuel depleted can be significant. Adaptation of renewable energy has therefore become important for both environmental and economic reasons.   In this master thesis a Life Cycle Assessment of Ericsson’s Managed Rural Coverage (MRC) solution was made. Four main life cycle stages were included: manufacturing, transportation, operation and end-of-life treatment. MRC is an off-grid site solution consisting of electronic communication equipment (radio base station, base station controller, hub, cable) photovoltaic cells, battery, antenna, and constructions part (antenna pole, tower and foundation). This study also includes the satellite connection as well as Ericsson and operator activities in the assessment. The MRC distinguishes itself from the conventional base stations, by its significant decrease of energy consumption in its operational stage as well as the business model around the offering. The assessment in this thesis was carried out in accordance with data retrieved from an Ericsson’s pilot system in Dungunab, Sudan. The ISO 1404X series of LCA standards was followed and Gabi software w used to evaluate the results.   The carbon footprint was found to be 0.3 kg CO2e/subscriber for the pilot setup. These calculations were based on an assumption that each pilot site serviced 1000 users. The maximum number of subscribers can be about 3200, which would decrease the life cycle CO2 emissions per user by 2/3. According to the sensitivity analysis the maximum CO2 emissions for a conservative MRC scenario is less than 1 kg CO2e/subscriber. Although this figure represents a very conservative scenario, the result is low in comparison with an average GSM network which has an approximate carbon footprint of 15 kg CO2e/subscriber. It is important to note that the MRC is not intended to replace all conventional macro RBS sites due to limitations in performance and capabilities, but is rather a complement to conventional macro radio base station sites for applicable scenarios. / <p>Thesis registration number: EGI-2013-024MSC  EKV941</p>

Smart antenna systems are employed to overcome multipath fading, extend range, and increase capacity by using diversity or beamforming techniques in wireless communication systems. Understanding of the smart base antenna performance mechanisms for various environments is important to design cost effective systems and network. This dissertation focuses on the experimental characterization and modeling of the smart base station antenna performance for various propagation environment scenarios. An eight-channel Virginia Tech smart base station antenna testbed was developed to investigate performances of three reverse link diversity methods. The experiment campaign resulted in 245 sets of collected data over 83 measurement sites, which were used to compare the performance of space, polarization, and angle diversity under identical conditions. Measured propagation path loss, envelope correlation coefficients, power imbalances, and mean effective gain (MEG) are characterized as a function of distance between the base station and the mobile terminal to illustrate the diversity performance mechanisms over different propagation environments. The performance of the three base station diversity methods with selection combining (SC), maximal ratio combining (MRC), and equal gain combining (EGC) techniques for both urban and suburban non-line-of-sight (NLOS) environments are presented and summarized using the measured data. Forward-link performance of a twelve-fixed narrow-beam base station antenna system for urban NLOS environments is investigated using the same measured data. A new procedure is introduced to experimentally model the forward-link performance of muitlple-fixed narrow-beam (MFNB) antennas using the measured reverse-link vector channel response. The experimentally calculated lower bound performance result shows that it achieves 2.5 to 2.8 times higher average RF SIR compared to the conventional three-sector base station system for typical urban NLOS multipath fading environment conditions. Also, a new mobile user angle estimation algorithm using the muitlple-fixed narrow-beam antennas for NLOS multipath fading environment conditions is developed and the experiment results are presented. / Ph. D.

In the early 90s¡¦, the government of the Republic of China, Taiwan (ROC) declared the end of martial law. Taiwanese society has moved toward multi-dimensional development, which includes the greater liberal awareness of the public, as well as gradually forming various but unique social cultures. Among these cultural changes is the right to public dispute. In the past two decades, several public disputes have occurred; from the dispute against environmental pollution by the petrochemical industry, including the Chinese Petroleum Corporation, followed by the establishment of a Du Pont chemical factory, the rejection of garbage disposal plant & incinerator building, the anti-construction of nuclear power plants & the Mei Nong reservoir. To attract more customers and to pre¡Vdominate the potential market, competitors in the telecommunication industry have implemented strategies to build excess mobile base station to enhance the quality of the signal reception. From recent scientific research, there is no clear evidence to prove that electromagnetic wave signals from mobile telecommunications have any direct impact on human health. In the Year 2000, the Executive Environmental Department in Taiwan has officially announced that electromagnetic wave signals from mobile telecommunications were not a source of pollutants. However, the objection of anti-establishing mobile base station has gradually become one of the leading issues of public dispute. The dispute approaches have tended to be radical and irrational, which has lead to strong violence. In the mean time, the government and the telecommunication industry are not able to respond to and resolve the current situation. These issues not only threaten the ability for the mobile telecommunication industry to survive, but cost an incredible amount of the social resource which it is also a great concern for the similar conditions in future society. The research motivations were developed by considering the special cultural backgrounds mentioned above. The literature review includes the following research areas: conflict management; the crises interventional communication; negotiating skills; legislation process study; and the theory of outsourcing study. Furthermore, surveys on professional groups were completed to seek expertise and feedback to help resolve public radical situations. Interviews were also conducted on some key radical and irrational people to increase the public awareness about the severity of disputes. In this study, the author also investigates reasons behind public disputes and what the public has experienced and learned. To summarize, the findings of this study: 1. In the current stage, the managerial approach only resolves a radical situation as it happens; a long term and systematic methodology is still unavailable and yet to be developed. Even though the short term resolution allows authorities to accumulate precious experiences in managing public pressure, the current methodology can not effectively prevent and avoid public disputes occurrence. 2. The fundamental idea from authorities is still in favor of ¡§technical educations¡¨ which permits technicians to take major responsibilities in implementing the idea of ¡§technical skill demonstrations¡¨ to communicate and lead the agenda. However, the outcomes do not appear to be effective to those irrational and radical disputes. 3. Political power interventions mean the government is unable to provide a stable environment for industrial developments. There are politicians¡¦ interventions from different parties; public threatens and violence might also be the reasons that cause immobilized feedbacks from the government. Based on the investigation on the pros and cons of disputes on excess mobile base station and possible dispute modes, long term and short term solutions were developed. The solutions include: 1. Possible long term solutions: (1) Develop long term strategic plans, which enable the prevention of future dispute. The practical plans include media operations, professional propaganda planning, management for united industrial unions on public disputes and offers of technical and general product propagandas to the public. (2) Organizational structure justifications, traditional conceptual changes in public disputes and formations of special negotiation teams: the authority should initiate with its negotiation process based on public opinions rather than listed contents with technical issues. Professional teams should have the ability to implement the law, the public relationship and technology to the public. (3) A liberal and a specific budget support for individual projects. (4) Mobile base station embellishments and joint venture with the industrial union. (5) Provide outsourcing to professionalism. (6) Seeking for political assistances: Through democratic operations, the government should maximize its ability in public authority monitoring and the law execution. This also ensures and protects legal welfares for the mobile telecommunication industry. 2. Possible short term solutions: (1) General strategies in station selection issues. (2) New tactics formations. (3) Training professional negotiators. (4) Holding regular conferences, exchanging ideas which draw upon useful opinions, and editing ¡§Irrational mobile base station dispute management¡¨ reference handbook. (5) Educate the public to understand and obey the law. Using the law to protect and maintain basic rights for the mobile telecommunication industry. The final discussions conclude with some proposed solutions to manage public disputes. The future research recommendations to the mobile telecommunication industry, the professional team, and the governmental organizations are also included. The aim is to establish a rational and peaceful future society and provide a stable business environment for the mobile telecommunication industry.

International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / This paper discusses the design and implementation of the base station telemetry data processing system for the unmanned helicopter. The system designed is composed of code synchronizer, decoding and frame synchronizer as well as PCI bus interface. The functions of the system are implemented with very large integrated circuits and a standard PCI inserted card that is compact and easy to install. The result of flight performance tests shows that the system is reliable and can satisfy the requirements of telemetry system for unmanned helicopters.

This thesis is concerned with the energy efficiency of cellular networks. It studies the dominant power consumer in future cellular networks, the Long Term Evolution (LTE) radio Base Station (BS), and proposes mechanisms that enhance the BS energy efficiency by reducing its power consumption under target rate constraints. These mechanisms trade spare capacity for power saving. First, the thesis describes how much power individual components of a BS consume and what parameters affect this consumption based on third party experimental data. These individual models are joined into a component power model for an entire BS. The component model is an essential step in analysis but is too complex for many applications. It is therefore abstracted into a much simpler parameterized model to reduce its complexity. The parameterized model is further simplified into an affine model which can be applied in power minimization. Second, Power Control (PC) and Discontinuous Transmission (DTX) are identified as promising power-saving Radio Resource Management (RRM) mechanisms and applied to multi-user downlink transmission. PC reduces the power consumption of the Power Amplifier (PA) and is found to be most effective at high traffic loads. DTX mostly reduces the power consumption of the Baseband (BB) unit while interrupting transmission and is better applied in low traffic loads. Joint optimization of these two techniques is found to enable additional power-saving at medium traffic loads and to be a convex problem which can be solved efficiently. The convex problem is extended to provide a comprehensive power-saving Orthogonal Frequency Division Multiple Access (OFDMA) frame resource scheduler. The proposed scheduler is shown to reduce power consumption by 25-40% in computer simulations, depending on the traffic load. Finally, the thesis investigates the influence of interference on power consumption in a network of multiple power-saving BSs. It discusses three popular alternative distributed uncoordinated methods which align DTX mode between neighbouring BSs. To address drawbacks of these three, a fourth memory-based DTX alignment method is proposed. It decreases power consumption by up to 40% and retransmission probability by around 20%, depending on the traffic load.

This thesis presents a feasibility study on unobtrusive localization of GSM en- abled cellphones using a Fake Base Station (FBS). An FBS is a radio transceiver that emulates the behaviour of a legitimate GSM Base Station (BS) to fool unal- tered cellphones to connect with it. This feasibility study investigates how an FBS can be utilized to estimate positions of connected cellphones in an area of interest. We present a proof of concept system that consists of a mobile FBS that measures the Time Of Arrival (TOA) and Received Signal Strength (RSS) to a cell- phone. The positions of the mobile FBS are determined with GPS. We employ calibration-free localization algorithms as we assume unknown environments and unknown hardware. Our experiments in an outdoor 180x100 m2 Line-Of- Sight (LOS) environment show that our calibration-free localization algorithms provide an average localization error less than 10 meters, which is sufficient for most applications of interest. In addition, our experiments show that RSS-based localization outperforms TOA-based localization when the average distance be- tween the FBS and cellphone is roughly 50 meters. Our experiments show that TOA-based localization outperforms RSS-based localization when the average dis- tance increases to roughly 75 meters. This research is part of the Smart Savannah project in which a wide range of different surveillance systems are developed to protect rhinos from poachers. We envision that our localization system can be used to detect and localize these poachers in an unobtrusive way. In addition, we envision that our localization sys- tem can be used in Search And Rescue (SAR) operations to estimate the positions of cellphones of missing persons. / Detta examensarbete undersöker möjligheten att lokalisera mobiltelefoner med GSM teknologi genom att använda en Falsk Basstation (FBS). En FBS är en radio transceiver som emulerar beteendet hos en legitim GSM basstation för att lura omodifierade mobiltelefoner att ansluta till den. Undersökningen tar reda på hur en FBS kan användas för att estimera positionerna av anslutna mobiltelefoner inom ett målområde. För att undersöka detta har ett Proof-Of-Concept-system ta- gits fram. Systemet består av en mobil FBS som som mäter propageringstid (TOA) och mottagen signalstyrka (RSS). FBS:ens positioner bestäms med GPS. Systemet använder kalibreringsfria algoritmer för lokalisering, då vi antar att miljön och mobiltelefonernas hårdvara är okänd. Tester av systemet har utförts utomhus i ett 180x100 m2 Line-Of-Sight-område. Dessa tester visar att lokaliseringsalgorit- merna ger ett genomsnittligt fel på mindre än 10 meter. Detta anses vara till- räckligt för de flesta tillämpningar av intresse. Utöver detta visar även testerna att RSS-baserad lokalisering ger bättre resultat än TOA-baserad lokalisering när medelavståndet mellan FBS och mobiltelefon är omkring 50 meter. TOA-baserad lokalisering ger däremot ett bättre resultat än RSS-baserad lokalisering när me- delavståndet ökar till omkring 75 meter. Denna undersökning är en del av Smart Savannah projektet som innefattar flera olika övervakningssystem, utvecklade för att skydda noshörningar från tjuv- skyttar. Målet med vårt lokaliseringssystem är att det ska kunna användas för att upptäcka och lokalisera tjuvskyttar utan deras vetskap. Vi tror även att lokalise- ringssystemet kan användas vid eftersökning- och räddnings-operationer för att lokalisera försvunna personers mobiltelefoner. / Project Ngulia

Wireless sensor networks consist of many small sensor nodes with sensing, computation, and wireless communications capabilities. Recently, there have been numerous research results in the power consumption for routing protocol. Routing protocols in WSNs might difference depending on the application and network architecture. This paper focuses on reducing the power consumption for routing protocol of wireless sensor networks too. We present a routing protocol called ACRP. sensor nodes will organize many clusters voluntarily. Cluster heads will distribute time slot to the sensor nodes in the same cluster and sensor nodes will transmit data to cluster head in it¡¦s time slot. After the data had been aggregated by cluster heads, they will send the aggregated data to base station through the routing path that had been established. In addition, in order to lengthen the living time of wireless sensor network, the base station will periodically adjust the amount of sensor nodes in all clusters according to the cluster information.

Novel designs of three-dimensional patch antennas for beamdwidth enhancement and broadband peration have been proposed in this dissertation. For the beamwidth enhancement, the patch antenna with an inverted V-shaped patch has been proposed, and the antenna¡¦s radiation beamwidths have been broadened. Another beamwidth enhancement design using a three-dimensional square ground structure has also been demonstrated, and the 3-dB beamwidth of the CP radiation can reach more than 110¢X. In addition to the designs of beamwidth enhancement, the broadband patch antennas with a V-shaped patch, a W-shaped ground plane and a short probe-pin have been proposed. These novel structures can have significantly reduced probe-pin length and obtain a good impedance matching over a wide frequency range. Finally, a 1 ¡Ñ 2 broadband patch antenna array, suitable for base-station antenna applications for mobile communications systems, has also been studied.

Η διπλωματική εργασία περιγράφει την δομή του δικτύου GSM,DCS,UMTS, την διαδικασία δρομολόγησης μίας κλήσης, τα βήματα σχεδιασμού και την περιαγωγή. Επίσης περιλαμβάνει τον σχεδιασμό τριών σταθμών, δύο σε αστικές περιοχές, έναν στην περιοχή της Αθήνας και έναν στην περιοχή των Πατρών και έναν σε αγροτική περιοχή, και συγκεκριμένα στην περιοχή Βρύναινα Μαγνησίας. / --

abstract: This thesis is a study of Bandwidth limitation of basestation power amplifier and its Doherty application. Fundamentally, bandwidth of a power amplifier (PA) is limited by both its input and output prematch networks and its Doherty architecture, specifically the impedance inverter between the main and auxiliary amplifier. In this study, only the output prematch network and the Doherty architecture follows are being investigated. A new proposed impedance inverter in the Doherty architecture exhibits an extended bandwidth compared to traditional quarterwave line. Base on the loadline analysis, output impedance of the power amplifier can be represented by a loadline resistor and an output shunt capacitor. Base on this simple model, the maximum allowed bandwidth of the output impedance of the power amplifier can be estimated using the Bode-Fano method. However, since power amplifier is in fact nonlinear, harmonic balance simulation is used to loadpull the device across a broad range of frequencies. Base on the simulated large signal impedance at maximum power, the prematch circuitry can be designed. On a system level, the prematch power amplifier is used in Doherty amplifier. Two different prematch circuitries, T- section and shunt L methods are investigated along with their comparison in the Doherty architecture at both back off power and peak power condition. The last section of the thesis will be incorporating the proposed impedance inverter structure between the main and auxiliary amplifiers. The simulated results showed the shunt L prematch topology has the least impedance dispersion across frequency. Along with the new impedance inverter structure, the 65% efficiency bandwidth improves by 50% compared to the original impedance inverter structure at back off power level. / Dissertation/Thesis / Masters Thesis Electrical Engineering 2014