This thesis studies advanced error control schemes using turbo-like codes, turbo-like coded modulations, turbo hybrid-ARQ (Automatic Repeat reQuest) schemes, and rate compatible puncturing techniques for reliable and adaptive commercial and tactical spread-spectrum communications, especially for code-division multiple access (CDMA) cellular systems and direct-sequence (DS) and frequency-hopping (FH) anti-jam systems. Furthermore, we utilize both the maximum-likelihood (ML) bounding techniques and convergence analysis to design and analyze various turbo-like coding schemes that show different behaviors in error performance from conventional trellis coding schemes. In the area of DS-CPM, we propose a DS concatenated coded CPM system for pulse-noise jamming channels and an anti-jam iterative receiver utilizing jammer state information. We also design a mixed concatenated CPM system that mixes CPM schemes with different convergence characteristics. In addition, we present the ML bound and convergence analysis for the jamming channel. In the area of FH-CPM, we propose anti-jam serially concatenated slow FH-CPM systems, whose phase is continuous during each hop interval, along with coherent and non-coherent iterative receivers. We also propose an iterative jamming estimation technique for the iterative receiver. In the area of multi-h CPM, we propose a power- and bandwidth-efficient serially concatenated multi-h CPM along with an appropriate iterative receiver structure. Serially concatenated multi-h CPM is shown to outperform single-h CPM. To design adaptive and versatile error control schemes using turbo-like codes for packet-data networks, we propose turbo hybrid-ARQ (HARQ) and rate compatible puncturing techniques for retransmission. In the area of turbo hybrid-ARQ, we propose a Type-I turbo HARQ scheme using a concatenated RS-turbo code and a packet combining technique for W-CDMA system to improve the performance of error and decoding latency. The W-CDMA system including the fast power control and coherent Rake receiver with a channel estimation technique for multipath fading channels is considered. Finally, in the area of rate compatible punctured turbo-like codes, we propose rate compatible punctured turbo (RCPT) codes and rate compatible punctured serially concatenated convolutional (RCPS) codes along with their puncturing methods. In addition, we propose Type-II RCPT-HARQ and RCPS-HARQ schemes to perform an efficient incremental redundancy retransmission.

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The main goal of this thesis is to create a continuous phase modulated radio system with a recursive least square equalizer. The two tested channel models are typical urban and rural area. The result of the performance of this radio system is displayed in Matlab plots as the bit error rate. Three error rates are displayed; with error correction, without error correction and the rate of received incorrect message bursts. Conclusions are also drawn of the performance of the radio system in kbit/sec of bandwidth when the different channel models are used. The performance is also divided into how the equalizer handles inter symbol interference or a fading channel without inter symbol interference. / I detta examensarbete har ett fasmodulerat radiosystem simulerats, fokusering ligger på kanalutjämnare som är av typen recursive least square (RLS). RLS utjämnaren har testats med två olika gsm kanalmodeler, dels typical urban som simulerar radioförbindelser i stadsmiljö den andra modellen är rural area där sändare och mottagare kan se varandra. Tre olika resultat presenteras; med felrättande koder, utan felrättande koder och mängden icke korrekta datapaket. Slutsatser dras om radiosystemets bandbredd när de olika kanalmodellerna används vid olika brusmängd. Även utjämnarens förmåga att hantera inter-symbol interference och fading utvärderas också.

This thesis is a study of harmonized continuous phase modulation (H-CPM) coupled with receive diversity as applied to mobile radio communication applications. H-CPM is the modulation technique specified by the American Public Safety Communication Official Project 25 (APCO P25) Phase 2 standards, which is focused on public safety applications. Practical implementation of an H-CPM maximum likelihood sequence estimator (MLSE) receiver requires complex reduction techniques to ensure a cost effective form. In addition, it must be able to handle a fast fading environment, which is often encountered in public safety applications. Here, the reduction of receiver complexity and the combating of fast fading situations are investigated via MATLAB simulation. By using tilted phase and frequency pulse truncation techniques, the complexity of an H-CPM MLSE receiver is successfully reduced. In particular, the original 384-state receiver is first reduced to a 192-state receiver through the use of tilted phase. Then it is further reduced to 48-states and finally to 12-states by applying frequency pulse truncation. Simulation, assuming static channels, shows that the bit error rate (BER) performance of a 12-state receiver is essentially identical to that of a 384-state receiver, despite a 97% reduction in computational complexity. To take into account the effects of fading, channel gain estimation via persurvivor processing (PSP) is incorporated into the reduced complexity MLSE receiver. Using a weighted-sum approach to the PSP gain estimates, it was found that at Doppler shifts of 5 Hz, 40 Hz and 80 Hz, the receiver performance was comparable to that obtainable by rival techniques. To further reduce the effect of fading, receive diversity combining was investigated, where a three-antenna diversity scheme is applied to the reduced state PSP-based MLSE receiver. Three different combining techniques, namely selective combining (SC), equal gain combining (EGC) and maximum ratio combining (MRC) were compared. It was found via simulation that the best performance is achieved using MRC, with as much as 14dB improvement achieved by applying triple diversity MRC.

Esta dissertação descreve o desenvolvimento de um sistema de planejamento e controle gerencial que utiliza a metodologia PERT/CPM. O objetivo do trabalho foi a criação de um sistema de planejamento voltado ao pequeno e médio usuário que permitisse grande interação deste com o problema. São descritas todas as fases do projeto, desde as análises iniciais do problema e proposta de alternativas para o modelo de representação, até a descrição da implementação. A implementação foi realizada em um computador do tipo APLLE II dando especial atenção ao projeto do diálogo usuário-sistema. / This work describes the development of a planning, management and control system based on the PERT/CPM methodology. The goal was to develop an interactive planning system to be used by the small and middle user. All the project phases are describe, from the problem analysis and alternatives of model representation up to the description of the implementation. The implementation was made in a Apple II computer emphasizing the project of the user - system language.

Esta dissertação descreve o desenvolvimento de um sistema de planejamento e controle gerencial que utiliza a metodologia PERT/CPM. O objetivo do trabalho foi a criação de um sistema de planejamento voltado ao pequeno e médio usuário que permitisse grande interação deste com o problema. São descritas todas as fases do projeto, desde as análises iniciais do problema e proposta de alternativas para o modelo de representação, até a descrição da implementação. A implementação foi realizada em um computador do tipo APLLE II dando especial atenção ao projeto do diálogo usuário-sistema. / This work describes the development of a planning, management and control system based on the PERT/CPM methodology. The goal was to develop an interactive planning system to be used by the small and middle user. All the project phases are describe, from the problem analysis and alternatives of model representation up to the description of the implementation. The implementation was made in a Apple II computer emphasizing the project of the user - system language.

Esta dissertação descreve o desenvolvimento de um sistema de planejamento e controle gerencial que utiliza a metodologia PERT/CPM. O objetivo do trabalho foi a criação de um sistema de planejamento voltado ao pequeno e médio usuário que permitisse grande interação deste com o problema. São descritas todas as fases do projeto, desde as análises iniciais do problema e proposta de alternativas para o modelo de representação, até a descrição da implementação. A implementação foi realizada em um computador do tipo APLLE II dando especial atenção ao projeto do diálogo usuário-sistema. / This work describes the development of a planning, management and control system based on the PERT/CPM methodology. The goal was to develop an interactive planning system to be used by the small and middle user. All the project phases are describe, from the problem analysis and alternatives of model representation up to the description of the implementation. The implementation was made in a Apple II computer emphasizing the project of the user - system language.

In modern wireless communication systems, such as satellite communications and wireless networks, the need for higher data rates without the need for additional transmit power has made Continuous Phase Modulation (CPM) one of the most attractive modulation schemes in band limited channels. However, as the data rates keep increasing, the spectral width of the CPM signal increases beyond the channel bandwidth and performance becomes constrained by the intersymbol interference (ISI) that results from band-limiting filters. We propose two approaches to the problem of equalization of band-limited CPM signals. First, our efforts are focused on shortening the channel impulse response so that we can use a low complexity MLSE equalizer. We implement the channel truncation structure by Falconer and Magee and adapt it to work with CPM signals. This structure uses a, a more derivable, pre-filter to shape the overall response of the channel, so that its impulse response is of shorter duration. Simulation results show that near-MLSE performance can be obtained while dramatically reducing MLSE equalizer complexity. In our second approach, we focus on eliminating the group-delay variations inside the channel passband using an FIR pre-filter. We assume the channel to be time-invariant and provide a method to design an FIR filter so that -when convolved with the band limiting filter - it results in more constant group-delay over the filter passband. Results show that eliminating the group-delay variations in the band limiting filter passband reduce the amount of ISI and improve bit error rate performance. / Master of Science

Made available in DSpace on 2016-08-10T10:40:19Z (GMT). No. of bitstreams: 1 KARINE GOMES BEZERRA DE ALCANTARA.pdf: 5389542 bytes, checksum: dc9ede65ba065fe001b67486f091d942 (MD5) Previous issue date: 2012-09-13 / Despite the construction sector being one of the largest sectors in the economy, it has its own specific characteristics with abundant movement of financial resources and absorption of labor. Even though its importance, it has major flaws regarding the planning process for residential development. There are few techniques that assist in production schedule aimed at producing vertical and horizontal sequential works.The CPM method, by utilizing heuristic rules of programming, enables the manager to view constructive scenarios. This technique associated with the concept of resource leveling remedies common problems of construction delays and excessive use of resources for project execution. Also, line of balance, a technique used in this study, displays the flaws and gaps in production, reducing the idleness of labor and the leveling of the rate of production. The objective of this study is to compare planning techniques of vertical sequential works, in order to get better performance based on the reduction of time and resource optimization. This study developed analysis and demonstrations of the effectiveness of tactical and operational planning of four enterprises with particular characteristics and differentiated from each other in order to test and process the data obtained by the work scenarios of executive managers, showing the best alternative of execution for the type of enterprise studied. Therefore it is concluded that the proposed techniques are easy to use, have specific performance, feature complementary graphical visualizations and proven to be very effective in making decisions. Both associated techniques generate excellent results for works of a repetitive nature. / O setor da construção, apesar de ser um dos maiores setores da economia, tem características próprias em especial pela grande movimentação de recursos financeiros e absorção de mão de obra. Apesar de sua importância, apresenta grandes falhas quanto ao processo de planejamento de empreendimentos residenciais. Existem poucas técnicas que auxiliem na programação de produção direcionados a obras verticais e horizontais seriadas. O método CPM, por utilizar regras heurísticas de programação, possibilita ao gestor a visualização do cenário construtivo. Essa técnica, associada ao conceito de nivelamento de recursos permite sanar problemas comuns de atrasos de obras e uso excessivo de recursos para a execução de projetos. A linha de balanço, técnica também empregada, permite visualizar as falhas e folgas de produção, reduzindo a ociosidade de mão de obra e o nivelamento do ritmo de produção. O objetivo deste trabalho é comparar técnicas de planejamento de obras horizontais seriadas, para a obtenção do melhor desempenho produtivo com base na redução de tempos e otimização de recursos. Neste estudo, foram desenvolvidas análises e demonstrações da eficácia do planejamento tático e operacional de quatro empreendimentos com características particulares e diferenciadas entre si, visando a comparação e o tratamento dos dados obtidos pelos cenários executivos dos gestores das obras, demonstrando assim a melhor alternativa de execução para a tipologia do empreendimento de estudo. Conclui-se que as técnicas propostas são de fácil aplicação, possuem desempenhos específicos, possuem visualizações gráficas complementares e mostraram-se muito eficazes no processo de tomada de decisões, gerando excelentes resultados para obras de natureza repetitivas.

Continuous phase modulation~(CPM) is a non-linear, constant-envelope modulation scheme with memory, known for its bandwidth and power efficiency. Multi-h CPM uses multiple modulation indices in successive symbol intervals to improve the error performance as compared to single-h CPM~(basic CPM that utilizes only a single modulation index). One of the major applications of multi-h CPM is in aeronautical telemetry systems. Modern aeronautical devices host an increasing number of sensors, which can transmit flight testing data to the ground station. However, this excess data transfer increases the intersymbol interference, and thus channel equalization is required at the receiver. The objective of our research is to propose low-complexity frqeuency-domain equalization~(FDE) techniques for multi-h CPM waveforms. For a modulation scheme with memory, such as CPM, the cyclic constraint on the FDE block necessitates the use of an extra segment of symbols, called intrafix or tail segment. We have used very simple geometric arguments to derive upper and lower bounds on the length of the intrafix in terms of the parameters of the modulation scheme and the Frobenius number. It is concluded that the length of the intrafix for multi-h CPM schemes is typically shorter than those required for single-h modulation schemes. We propose two receiver architectures; one uses a matched filter front end, while the other utilizes a fractional sampling front end. Various simplifications are proposed for each architecture, and the trade-off between receiver complexity and performance is analyzed and verified through detailed simulation studies.