Thesis (M. App. Sc.)--Carleton University, 2002. / Includes bibliographical references (p. 106-107). Also available in electronic format on the Internet.

Thesis (M. App. Sc.)--Carleton University, 2004. / Includes bibliographical references (p. 78-80). Also available in electronic format on the Internet.

Thesis (M.App.Sc.) - Carleton University, 2005. / Includes bibliographical references (p. 80-81). Also available in electronic format on the Internet.

Thesis (M.App.Sc.) - Carleton University, 2007. / Includes bibliographical references (p. 81-85). Also available in electronic format on the Internet.

Thesis (Ph. D.)--Brigham Young University. Dept. of Electrical and Computer Engineering, 2007. / Includes bibliographical references (p. 185-197).

Thesis (M.S.)--Brigham Young University. Dept. of Physics and Astronomy, 2008. / Includes bibliographical references (p. 149-157).

Thesis (M.E.)--University of Canterbury, 2006. / Typescript (photocopy). "November 2006." Includes bibliographical references (p. [137]-142). Also available via the World Wide Web.

A multiple-antenna-multiple-equalizer (MAME) system is proposed for overcoming cochannel interference (CCI) in code-division multiple access (CDMA) indoor wireless systems. The main advantage of the MAME system is the enhanced interference suppression capability as compared with many existing approaches. Thus, the use of the MAME system can lead to an increase in the capacity of the CDMA system. In the MAME system, a fractionally-spaced equalizer (FSE) is used to process the signal at each antenna. The number of antennas or the tap spacing of the FSEs is not fixed and inherent flexibility is available to the designer. In particular, CDMA indoor wireless systems are best suited to use the interference suppression capabilities of the MAME system. It is shown that spectral correlation present in user signals is the reason for the interference suppression capability of the MAME system. Moreover, the MAME system is interpreted as a dual-domain diversity combiner. Spatial and bandwidth-domain diversity are used and the relative importance of the diversity domains is discussed. These discussions offer new insights into the interference suppression capabilities of the MAME system and give a clear picture of its workings. Extensive simulation results are presented to illustrate the performance of the MAME system under various conditions. Optimal or minimum mean-squared error (MMSE) results are first presented to illustrate the superior interference suppression performance. The effects of the number of antennas, tap spacing, receive filtering, spectral correlation, diversity domains, and near-far conditions on performance are examined and results obtained support the arguments presented earlier in the thesis. The FSEs in the MAME system are implemented as adaptive filters and the mean-squared- error (MSE) performance is investigated. A quasi-Newton (QN) algorithm is recommended over other adaptive filtering algorithms because of ill-conditioning of the autocorrelation matrix in the MAME system. Simulation results confirm the superior convergence performance of the QN algorithm. Decision-directed equalization is also investigated and bit-error rate (BER) results presented illustrate that the gains in the MMSE performance will most likely translate into gains in BER performance. The BER performance in near-far and birth of interferers conditions illustrate that the MAME system is a promising solution to counter these problems. The thesis concludes with an indoor wireless strategy based on the MAME system which offers the following advantages: 1. More users than the processing gain of the CDMA system can share the same bandwidth. 2. No information about code sequences is needed at the receiver. 3. Simple code sequence allocation schemes can be used at the transmitter. 4. Variable numbers of users can be accommodated. 5. Simple power control and error-correction coding schemes can be used. / Graduate

Orientadores: Aldário Chrestani Bordonalli, Júlio César Rodrigues Fernandes de Oliveira / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-17T21:04:54Z (GMT). No. of bitstreams: 1 Nascimento_VitorValedo_M.pdf: 29215794 bytes, checksum: f49ac3ba86cf6fbafde603d3e6eec99e (MD5) Previous issue date: 2011 / Resumo: As variações de potência de entrada em amplificadores a fibra dopada com érbio induzem alterações em seu perfil de ganho já dependente do comprimento de onda do sinal de entrada. Assim, em redes de multiplexação por divisão em comprimento de onda (WDM - wavelength division multiplexing) reconfiguráveis, a não uniformidade do perfil de ganho pode prejudicar a recepção do sinal tanto por falta quanto por excesso de potência. Neste contexto, este trabalho apresenta uma proposta de equalizador dinâmico para o amplificador a fibra dopada com érbio (EDFA - erbium doped fiber amplifier) com controle automático de ganho que é utilizado em redes ópticas reconfiguráveis. O projeto deste dispositivo baseou-se numa cascata de cinco filtros opto-cerâmicos senoidais que, de acordo com o perfil de ganho de operação do amplificador, adaptava-se para compensar a falta de equalização entre canais. Devido à alta sensibilidade da resposta espectral de filtros opto-cerâmicos com a temperatura, houve a necessidade de se desenvolver também um modelo para a função de transferência dos filtros onde o efeito da temperatura estivesse diretamente incluído em seus algoritmos de controle. Após a introdução deste sistema dinâmico de equalização na saída do EDFA, observou-se, experimentalmente, uma significativa equalização entre canais, melhor que 1 dB, para uma ampla faixa de temperatura de operação do dispositivo e variações extremas na potência de entrada do EDFA / Abstract: Input optical power and gain variations at erbium doped fiber amplifiers induce fluctuations in its gain profile, which already presents a severe wavelength-dependence. In reconfigurable WDM networks this feature can compromise received signal performance due to lack or excess of optical power. Thus, this work suggests a new dynamic gain equalizer approach intended for EDFAs with electronic gain control in reconfigurable optical networks. The device is based on five opto-ceramic sinusoidal filters that dynamically adapt themselves to compensate power channel imbalances caused by EDFAs due to network resetting. Since opto-ceramic filters are extremely temperature sensitive, it was necessary to develop a transfer function model for filter control that directly included this temperature dependence. After placing the dynamic equalizer at an EDFA output, it was experimentally observed significant reduction of the power imbalance, better than 1 dB, for a wide temperature range and extreme EDFA input power oscillation / Mestrado / Telecomunicações e Telemática / Mestre em Engenharia Elétrica

Equalizing is a fundamental processing application in music mastering, where the engineer may adjust the overall frequency balance of the material and make surgical adjustments to narrow regions. There is some previous research made on acclaimed engineers’ usage of equalizers in mastering, however little information is presented on why certain choices are made and how the EQ specifically is incorporated into the workflow. In this qualitative study, six mastering engineers were interviewed to discover the reasoning behind their choices of EQs in music mastering. Also investigated are the opinions and preferences for sonic characteristics of different types of EQs, as well as what important qualities are in EQs for mastering in general. In order to understand some statements made by the mastering engineers regarding the sonic characteristics of analog devices, a literature review in combination with an additional interview with a service technician was made. The literature review aimed to provide some insight on what electronic components and aspects of the general design affects the sonic signature of analog devices the most. The thematic analysis showed that there are some agreement amongst the engineers considering the implementation of EQ with regards to genre and certain tasks. The respondents agreed that tube devices are not to be used for every instance since these are highly coloring devices. Transistor EQs on the other hand are perceived as fairly transparent in comparison, yet still imparting the sonic characteristics of an analog device. For those using a hybrid setup, digital plugins are generally used for surgical application and also, in some cases, for preservation of quality. Although setups may vary between every engineer, this study verifies that the most important factor in the choice of tool is knowing how the devices work.