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Cost Optimized Radio-over-Fiber SystemDamas, Jacqueline 06 February 2024 (has links)
The demand of smaller and portable electronic devices has contributed to the realisation of compact embedded systems using PCB miniaturization techniques. The commercial market is faced with competition of handheld users’ devices in medical, communication and automotive industries which are smaller and lighter electronic devices. The possibilities of higher degree of integration in planar technology using cost effective electronic components has lead to different art of design and fabrication of compact units. In this work, a central station and a base station front-end with small form factor have been realized using commercial components on PCBs. These electronic compacts units were integrated in the IF-over-Fiber system architecture.
The IF-over-Fiber architecture comprised of miniaturized electronic components for quadrature modulation and upconversion. The central station supports multi-Gbps data rate modulation formats in order to increase the spectral efficiency of the transmitted information. Multilevel modulation formats are considered spectrally efficient and can double the transmission capacity by transmitting more information in the amplitude, phase, polarization or a combination of all. The BS front-end comprises of the 60 GHz upconverter and a 60 GHz planar 2×2 microstrip antenna. The 10 GHz IF carrier allows an optical transmission with higher spectral efficiency in optical domain, as well as it is less susceptible to dispersion induced power fading inherent in optical fiber. Characterization of the designed central station and base station front-end through measurements are presented and discussed. The IF-over-Fiber system analysis is made for the 2 Gbps QPSK transmission with respect to error vector magnitude (EVM), eye and constellation diagrams.
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Performance Modelling and Analysis of Handover and Call Admission Control Algorithm for Next Generation Wireless NetworksSha, Sha January 2011 (has links)
The next generation wireless system (NGWS) has been conceived as a ubiquitous wireless environment. It integrates existing heterogeneous access networks, as well as future networks, and will offer high speed data, real-time applications (e.g. Voice over IP, videoconference ) and real-time multimedia (e.g. real-time audio and video) support with a certain Quality of Service (QoS) level to mobile users. It is required that the mobile nodes have the capability of selecting services that are offered by each provider and determining the best path through the various networks.
Efficient radio resource management (RRM) is one of the key issues required to support global roaming of the mobile users among different network architectures of the NGWS and a precise call admission control (CAC) scheme satisfies the requirements of high network utilization, cost reduction, minimum handover latency and high-level QoS of all the connections.
This thesis is going to describe an adaptive class-based CAC algorithm, which is expected to prioritize the arriving channel resource requests, based on user¿s classification and channel allocation policy. The proposed CAC algorithm couples with Fuzzy Logic (FL) and Pre-emptive Resume (PR) theories to manage and improve the performance of the integrated wireless network system. The novel algorithm is assessed using a mathematical analytic method to measure the performance by evaluating the handover dropping probability and the system utilization.
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Achieving The Optimal Diversity-Multiplexing Gain Tradeoff For MIMO Channels With And Without FeedbackPawar, Sameer A 06 1900 (has links) (PDF)
No description available.
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Systém řízení osvětlení využívající bezdrátovou komunikační síť / Lighting control system using a wireless communication networkLevek, Vladimír January 2011 (has links)
The aim of this thesis is to create and describe the wireless system for lighting control. A part of the work is the creation of modules for switching lighting and the creation of their operating programs. The first chapter briefly describes the way how the lighting control works and contains general requirements for the intelligent home. Further, there is a description of IQRF system, which serves as a wireless platform for the system. Next part of the thesis describes individual modules in terms of hardware and software. One part of the work covers the description of the transmission protocol. The attachment includes a listing of all operating programs for this wireless control system.
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