Today represents vibration analysis an inseparable part of the product design, especially aeronautical components, machine tools etc. One of the vibration analysis methods is the so-called modal analysis, which determines the modal parameters of the researched structure. This paper deals with a comparison of two commonly used approaches, namely „Single Input Multiple Output“ (SIMO) and „Multiple Input Multiple Output“ analysis (MIMO). A MIMO procedure of measurement is developed and discussed. Both analyses are executed by the same conditions on the milling machine based on parallel kinematics in order to objective comparison. The results show that the choice of the so-called reference points is very important. In case both references are appropriately selected, the MIMO analysis gives better results that the SIMO one.

Today represents vibration analysis an inseparable part of the product design, especially aeronautical components, machine tools etc. One of the vibration analysis methods is the so-called modal analysis, which determines the modal parameters of the researched structure. This paper deals with a comparison of two commonly used approaches, namely „Single Input Multiple Output“ (SIMO) and „Multiple Input Multiple Output“ analysis (MIMO). A MIMO procedure of measurement is developed and discussed. Both analyses are executed by the same conditions on the milling machine based on parallel kinematics in order to objective comparison. The results show that the choice of the so-called refer-ence points is very important. In case both references are appropriately selected, the MIMO analysis gives better results that the SIMO one.

<p>In this thesis, noncoherent cooperative amplify-and-forward (AF) half-duplex relay systems and wireless communication systems equipped with a single transmitter antenna and multiple receiver antennas (SIMO) are considered, in which perfect channel information is unavailable at the destination end. For the AF half-duplex relay systems, the use of the least square error (LSE) receiver is proposed for detection. By using perturbation theory on the eigenvalues, an asymptotic formula of pairwise error probability for the LSE detector is derived. The result shows that the full diversity gain function mimics coherent cooperative AF half-duplex relay systems, whereas the coding gain function mimics noncoherent multi-inputs multi-outputs (MIMO) systems.</p> <p>In order to design full diversity noncoherent signals for both systems, a novel concept called a uniquely factorable constellation (UFC) is proposed in this thesis. It is proved that such a UFC design guarantees the unique blind identification of channel coefficients and transmitted signals in a noise-free case for the SIMO channel by only processing two received signals, as well as full diversity with the noncoherent maximum likelihood (ML) receiver in a noisy case. By using the Lagrange's four-square theorem, an algorithm is developed to efficiently and effectively design various sizes of energy-efficient unitary UFCs to optimize the coding gain. In addition, a closed-form optimal energy scale is found to maximize the coding gain for the unitary training scheme based on the commonly-used quadrature amplitude modulation (QAM) constellations.</p> / Master of Applied Science (MASc)

While using iron castings behind temperature of 500 oC namely at cyclic heat straining, degradation of structure and breaching iron castings. For this purpose introduce cast iron with content of Si and Mo. Focusing on improvement of SiMo51 for increased high-temmperature corrosion-and fatigue life in exhaust-gas temperatures up to 800 oC. Thesis set up survey types alloys, properties, and way of casting production.

Master of Science / Department of Electrical and Computer Engineering / Balasubramaniam Natarajan / Recently, user-cooperative MIMO (multi-input multi-output) systems have been generating significant interest due to their capacity/performance gains over SISO (single-input single-output) systems. In cooperative MIMO architectures, individual nodes with single antennas collaborate with each other to act as a MIMO unit. As a result, the individual node complexity associated with traditional MIMO implementations is alleviated. This feature is especially beneficial in sensor networks and cellular systems where individual node energy, size and cost are important constraints. Additionally, cooperative MIMO schemes provide all the benefits of traditional MIMO systems. In this work, we classify the cooperative MIMO systems into three different categories equivalent to classical MIMO, MISO and SIMO systems. For the three protocols, we quantify and compare the energy efficiency of Amplify-and-Forward (AF) and Decode-and-Forward (DF) schemes on a basic three node cooperative network. Total energy is calculated considering circuit energy as well as transmission energy. For AF and DF schemes, we set a target Symbol Error Probability (SEP) and evaluate the minimum transmission energy for achieving the target SEP. In this process,we first derive an approximation for SEP at high SNR. Then, we formulate the transmission energy calculation as an optimization problem subject to the target SEP and present the theoretical solution. The result is used to compare the total energy consumption of AF and DF for the three protocols. This is unlike most of the prior efforts that primarily focus on optimum allocation of limited total power to maximize the some peformance criterion. Since any wireless systems in order to operate have a set performance criterion, we intend to minimize the resources that is capable of achieving that.

This thesis report presents background knowledge about cognitive radio network (CRN) and investigates performance of underlay cognitive radio networks based on an adaptive power allocation policy of secondary transmitter (SU-Tx). In particular, it has been assumed that SU-Tx and primary user transmitter (PU-Tx) are equipped with a single antenna, while the corresponding receivers are equipped with multiple antennas. Additionally, SU-Tx operates under the joint constraint of its peak transmission power and outage constraint of the primary network. The probability density function (PDF) and cumulative density function (CDF) of the signal to interference and noise ratio (SINR) of SU over Rayleigh fading channel are derived. Using these two functions, a closed-form expression for the outage probability and an approximate expression for ergodic capacity of the considered system are obtained. Matlab simulation results are provided to validate the correctness of the analyses. The results show that simulation and analytical results closely match. The results show that the performance of SU increases as power of PU increases, but behaves the opposite after SU-Tx reaches its peak transmission power. Furthermore, the results reveal that as the number of antennas at the receivers (both SU and PU receivers) increases, the performance of the SU network increases. / maarig2000@gmail.com, marshed18@hotmail.com

Multiple-Input Multiple-Output (MIMO) communication using multiple antennas has received significant attention in recent years, both in the academia and industry, as they offer additional spatial dimensions for high-rate and reliable communication, without expending valuable bandwidth. However, exploiting these promised benefits of MIMO systems critically depends on fast and accurate acquisition of Channel State Information (CSI) at the Receiver (CSIR) and the Transmitter (CSIT). In Time Division Duplex (TDD) MIMO systems, where the forward channel and the reverse channel are the same, it is possible to exploit this reciprocity to reduce the overhead involved in acquiring CSI, both in terms of training duration and power. Further, many popular and efficient transmission schemes such as beam forming, spatial multiplexing over dominant channel modes, etc. do not require full CSI at the transmitter. In such cases, it is possible to reduce the Reverse Channel Training (RCT) overhead by only learning the part of the channel that is required for data transmission at the transmitter. In this thesis, we propose and analyze several novel channel-dependent RCT schemes for MIMO systems and analyze their performance in terms of (a) the mean-square error in the channel estimate, (b) lower bounds on the capacity, and (c) the diversity-multiplexing gain tradeoff. We show that the proposed training schemes offer significant performance improvement relative to conventional channel-agnostic RCT schemes. The main take-home messages from this thesis are as follows: • Exploiting CSI while designing the RCT sequence improves the performance. • The training sequence should be designed so as to convey only the part of the CSI required for data transmission by the transmitter. • Power-controlled RCT, when feasible, significantly outperforms fixed power RCT.

Submitted by Marta Toyoda (1144061@mackenzie.br) on 2018-02-06T23:04:35Z No. of bitstreams: 2 RICARDO SERIACOPI RABAÇA.pdf: 12578451 bytes, checksum: 9aa6f50946d5c917a7ea4e5b6841ef6f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Paola Damato (repositorio@mackenzie.br) on 2018-04-03T12:57:50Z (GMT) No. of bitstreams: 2 RICARDO SERIACOPI RABAÇA.pdf: 12578451 bytes, checksum: 9aa6f50946d5c917a7ea4e5b6841ef6f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-04-03T12:57:50Z (GMT). No. of bitstreams: 2 RICARDO SERIACOPI RABAÇA.pdf: 12578451 bytes, checksum: 9aa6f50946d5c917a7ea4e5b6841ef6f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-08-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Fundo Mackenzie de Pesquisa / This project presents the history, basic information and advantages of using Software De ned Radio (SDR), diversity, layer division multiplexing (LDM) technique and the latest digital TV standards in a digital communication system. These subjects have been relevant in the scienti c community, making the project attractive in terms of the possibility of discoveries and optimizations. After that, the implementation of a digital communication system using these technologies is proposed. This implementation was performed by means of GRC simulation software and the use of C++ and Python programming languages. Therefore, it was necessary to test the steps of coding, modulation and digital transmission / reception. Finally, tests were performed with systems that use diversity, for example, Single-Input Single-Output (SISO), as well as setting Single-Input Multiple-Output (SIMO), using the settings 1x 2, 1x3 and 1x4, in order to compare possible advantages in spectrum utilization, data rate and system robustness to interference. / O presente projeto apresenta o histórico, as informações básicas e as vantagens da utilização do rádio definido por software, do inglês Software Defined Radio (SDR), da diversidade, da técnica de multiplexacão por divisão em camadas, do inglês Layered Division Multiplexing (LDM) e dos mais modernos padrões de TV digital em um sistema de comunicação digital. Estes temas vêm repercutindo de forma relevante na comunidade científica, tornando o projeto atrativo em termos de possibilidade de descobertas e otimização. Posteriormente, a implementação de um sistema de comunicação digital unindo estas tecnologias _e proposta. Esta implementação foi realizada por meio do software de simulação GNU Radio Companion (GRC) e do uso das linguagens de programação C++ e Python. Para tanto, foi necessário testar as etapas de codificação, modulação e a transmissão/recepção digital. Finalmente, foram realizados testes com sistemas que utilizam diversidade, como, por exemplo, os métodos com uma entrada e uma saída, do inglês Single-Input Single-Output (SISO), além do método com uma entrada e múltiplas saídas, do inglês Single-Input Multiple-Output (SIMO), com as configurações 1x2, 1x3 e 1x4, com o intuito de comparar possíveis vantagens no aproveitamento do espectro, na taxa de dados e na robustez do sistema à interferências.

No description available.

The interest in the development of wireless high-speed data services is in response to the strong market demand for high-speed wireless Internet access. Current standards aim at delivering a peak data rate greater than 2Mbps on the forward link. Since data services and voice services are fundamentally different, new concepts were introduced in the design of the forward data channel. In addition, methods of evaluating the performance of a cellular CDMA system have to be revisited. This thesis proposes a method which can be used to find the forward link peak and average data rates, throughput and coverage of a cellular CDMA system which is capable of delivering high-speed wireless data. A summary of changes in design philosophy and recent advances in technologies which enable high-speed wireless data delivery are presented. The proposed method takes into account major aspects commonly found in the forward data channel and applies the generalized Shannon capacity formula for multi-element antenna (MEA) systems. The analysis focuses on the physical layer and is flexible enough to be adapted to various propagation environments, antenna configurations, multicode allocations, user distributions and cell site configurations. Sample numerical results for various multicode allocations are shown using a system model with two-tier interfering cells with one transmit antenna and two receive antennas operating under a frequency selective slow fading channel with propagation environment described by the Recommendation ITU-R M. 1225 indoor office, outdoor to indoor and pedestrian and vehicular test environments. Different transmit / receive antenna configurations and multicode allocations and their impact on the average data rate is also explored.