Design and realization of decimation filter for 24 bit Σ-Δ A/D converter

近十几年来，随着微电子技术的快速发展和计算机技术在集成电路中的应用，集成电路已发展到超大规模甚至是单片系统集成阶段，大大促进了数字技术的发展。数字技术具有速度快、精度高、抗干扰能力强等优点而得到广泛的应用，越来越多的电子设备已经从采用模拟电路实现而大范围地向数字化转变。随着数字化进程的深入，作为连接模拟和数字世界桥梁的模数转换器也同样成为研究热点，其中高位的Σ-Δ型A/D转换器作为高精度信号处理中的重要接口部件，由于其转换精度高而使它们在当今高精度信号处理领域中倍受青睐。因此本论文以实现性能良好的高位Σ-Δ型A/D转换器芯片为目标，设计和实现一款24位Σ-Δ型A/D转换器的关键部分——数字抽取...With the rapid development of microelectronic technology and the aid of computer technology in IC design and development, the scale and complexity of integrated circuits have been increasing exponentially over the past few decades. Due to its flexibility, high resolution, strong anti-interference and fast increasing processing power, more and more applications are using digital circuits and digita...学位：工学硕士院系专业：物理与机电工程学院物理学系_微电子学与固体电子学学号：2005130168

The FIELDS Instrument Suite for Solar Probe Plus: Measuring the Coronal Plasma and Magnetic Field, Plasma Waves and Turbulence, and Radio Signatures of Solar Transients.

NASA's Solar Probe Plus (SPP) mission will make the first in situ measurements of the solar corona and the birthplace of the solar wind. The FIELDS instrument suite on SPP will make direct measurements of electric and magnetic fields, the properties of in situ plasma waves, electron density and temperature profiles, and interplanetary radio emissions, amongst other things. Here, we describe the scientific objectives targeted by the SPP/FIELDS instrument, the instrument design itself, and the instrument concept of operations and planned data products

UML as a system level design methodology with application to software radio

Master'sMASTER OF SCIENC

The FIELDS Instrument Suite for Solar Probe Plus

NASA's Solar Probe Plus (SPP) mission will make the first in situ measurements of the solar corona and the birthplace of the solar wind. The FIELDS instrument suite on SPP will make direct measurements of electric and magnetic fields, the properties of in situ plasma waves, electron density and temperature profiles, and interplanetary radio emissions, amongst other things. Here, we describe the scientific objectives targeted by the SPP/FIELDS instrument, the instrument design itself, and the instrument concept of operations and planned data products

The Plasma Wave Experiment (PWE) on board the Arase (ERG) satellite

The Exploration of energization and Radiation in Geospace (ERG) project aims to study acceleration and loss mechanisms of relativistic electrons around the Earth. The Arase (ERG) satellite was launched on December 20, 2016, to explore in the heart of the Earth’s radiation belt. In the present paper, we introduce the specifications of the Plasma Wave Experiment (PWE) on board the Arase satellite. In the inner magnetosphere, plasma waves, such as the whistler-mode chorus, electromagnetic ion cyclotron wave, and magnetosonic wave, are expected to interact with particles over a wide energy range and contribute to high-energy particle loss and/or acceleration processes. Thermal plasma density is another key parameter because it controls the dispersion relation of plasma waves, which affects wave–particle interaction conditions and wave propagation characteristics. The DC electric field also plays an important role in controlling the global dynamics of the inner magnetosphere. The PWE, which consists of an orthogonal electric field sensor (WPT; wire probe antenna), a triaxial magnetic sensor (MSC; magnetic search coil), and receivers named electric field detector (EFD), waveform capture and onboard frequency analyzer (WFC/OFA), and high-frequency analyzer (HFA), was developed to measure the DC electric field and plasma waves in the inner magnetosphere. Using these sensors and receivers, the PWE covers a wide frequency range from DC to 10 MHz for electric fields and from a few Hz to 100 kHz for magnetic fields. We produce continuous ELF/VLF/HF range wave spectra and ELF range waveforms for 24 h each day. We also produce spectral matrices as continuous data for wave direction finding. In addition, we intermittently produce two types of waveform burst data, “chorus burst” and “EMIC burst.” We also input raw waveform data into the software-type wave–particle interaction analyzer (S-WPIA), which derives direct correlation between waves and particles. Finally, we introduce our PWE observation strategy and provide some initial results

Processamento eficiente de arranjos de microfones modulados em densidade de pulso

Orientador: Bruno Sanches MasieroDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de ComputaçãoResumo: Atualmente, os microfones digitais modulados por densidade de pulso (PDM) são amplamente utilizados em aplicações comerciais, já que esta é uma maneira eficiente de transmitir informação de áudio para processadores digitais em dispositivos móveis. No entanto, como o estado-da-arte em algoritmos de processamento digital de arranjos assume que todos os sinais recebidos dos microfones estão em uma representação em banda-base, estes microfones digitais requerem custosos filtros de decimação de alta ordem para converter o fluxo PDM para a modulação por código de pulso (PCM) em banda base. Assim, a implementação destes algoritmos em sistemas embarcados, onde os recursos de processamento são críticos, ou em circuitos integrados (VLSI), onde a energia consumida e área também são críticas, pode se tornar muito dispendiosa devido ao uso de dezenas de filtros de decimação para converter os sinais de PDM para PCM. Essa dissertação explora e propõe métodos eficientes em recursos para a implementação de arranjo de microfones. Com esse intuito, primeiro explora os atuais métodos de design de filtros de decimação e, baseado neles, propõe um algoritmo para fazer o seu design otimizando área e consumo de potência. Também são discutidas as vantagens e desvantagens de se realizar o processamento de arranjo de microfones diretamente nos sinais PDM ao invés dos sinais em PCM. Finalmente propõe um método eficiente para implementação de arranjos de microfones baseado em filtros maximamente planos (MAXFLAT). Como resultado, um novo método para o design de filtros de decimação que optimiza o número de somas por segundo é proposto, assim como demonstra-se que que um filtro espacial implementado no domínio PDM precisa de menos recursos que outras implementação no domínio do tempo. Conclui-se, portanto, que a implementação baseada em filtros MAXFLAT tem um melhor compromiso entre requisitos de armazenamento e poder de computação que o estado-da-arte e os métodos no domínio do PDMAbstract: Nowadays, pulse-density modulated (PDM) digital microphones are widely used on commercial applications as they have become a popular way to deliver audio to digital processors on mobile applications. However, as state-of-the-art array processing algorithms assume that all microphone signals are available in pulse-code modulated (PCM) representation, these digital microphones require costly high-order decimation filters to translate PDM bitstreams to baseband multi-bit PCM signals. In that manner, the implementation of microphone array algorithms in embedded systems, where processing resources are critical, or in very large-scale integration (VLSI) circuits, where power and area are critical, may become very expensive because of the use of the tens of decimation filters required to convert PDM bitstreams into PCM signals. This thesis explores and proposes resource-efficient methods to implement microphone array beamforming. For this purpose, it first reviews the state-of-the-art decimation filter design methods and proposes an algorithm to design decimation filters optimizing area and power consumption. Then it discusses the trade-offs of doing the beamforming calculations at the PDM bitstreams instead of PCM signals and proposes an architecture to implement beamformers without decimation filters. Finally it proposes an efficient approach to implement beamformers based on maximally flat (MAXFLAT) filters. As a result, a new generalized method to design decimation filters optimizing the number of addition per second is proposed, and it is shown that a beamformer implemented in PDM domain requires less resources for its implementation in time domain than other methods. It is concluded that the proposed MAXFLAT-based approach has better storage versus computation efficiency than state-of-the-art and PDM domain implementation approachesMestradoTelecomunicações e TelemáticaMestre em Engenharia Elétric

Digital Transmitter I/Q Calibration: Algorithms and Real-Time Prototype Implementation

Nowadays, the direct-conversion and the low-IF transceiver principles are seen as the most promising architectures for future flexible radios. Both architectures employ complex I/Q mixing for up- and downconversion. Consequently, the performance of the transceiver architectures can be seriously deteriorated by the phenomenon called I/Q imbalance. I/Q imbalance stems from relative amplitude and phase mismatch between the I- and Q-branches of the transceiver, thus resulting in self-interference or adjacent channel interference. This thesis addresses details of the real-time prototype implementation of the transmitter unit realizing a widely-linear least-squares-based I/Q imbalance estimation algorithm and a corresponding pre-distortion structure as previously proposed by Anttila et al. First transceiver architectures and radio transmitter principles are discussed with special emphasis on I/Q imbalance related aspects. Thereafter, the imbalance estimation principle itself is reviewed and a recursive version of it is derived. Then the implementation platform and software are introduced. After that, implementation details are discussed and implementation-related practical issues are addressed. Finally, simulation results and comprehensive RF measurement results from the real-time prototype implementation are presented. The work done in this thesis realizes a real-time prototype implementation of the WL-LS I/Q imbalance estimation algorithm and corresponding pre-distortion structure. In addition, the implementation is shown to give consistent results with Matlab simulations and it can operate on general purpose processors. /Kir10Nykyaikana suoramuunnos- ja matalavälitaajuuslähetin-vastaanotin periaatteet nähdään lupaavimpina arkkitehtuureina tulevaisuuden joustaville radioille. Molemmat arkkitehtuurit käyttävät taajuusmuunnoksissa kompleksista I/Q taajuus-sekoitusta. Tästä johtuen mainittujen lähetin-vastaanotinarkkitehtuurien suorituskykyä huonontaa ilmiö nimeltä I/Q epätasapaino, mikä johtuu suhteellisesta amplitudi ja vaihe epäsovituksesta modulaattorin I- ja Q-haarojen välillä. Tämän vuoksi signaaliin muodostuu itseishäiriötä tai viereisen kanavan häiriötä heikentäen radiotaajuisen signaalin puhtautta. Tässä diplomityössä esitellään reaaliaikaisen lähetin-vastaanotinprototyypin toteutus, jossa on käytössä Lauri Anttilan aiemmin julkaisema laajasti lineaariseen pienimmän neliösumman menetelmään perustuva I/Q epätasapainon estimointi algoritmi ja siihen liittyvä esivääristysrakenne. Aluksi esitellään lähetin-vastaanotinarkkitehtuurit ja niihin liittyvät pääperiaatteet painottaen I/Q epätasapainoon liittyviä asioita. Tämän jälkeen johdetaan I/Q epätasapainon estimointiin käytettävän algoritmin rekursiivinen versio ja esitellään toteutukseen käytettävä kehitysalusta ohjelmistoineen. Tämän jälkeen käydään läpi toteutuksen yksityiskohdat ja siihen liittyvät käytännön ilmiöt. Lopuksi esitellään simulaatiotulokset ja kokonaisvaltaiset radiotaajuusmittaukset reaali-aikaisesta prototyyppitoteutuksesta. Diplomityöprojektin tuloksena on radiolähettimen reaali-aikainen prototyyppi toteutus, jossa on käytössä laajasti lineaariseen pienimpään neliösummaan perustuva I/Q epäsovituksen estimointi ja vähentämis algoritmi. Implementaatio tuottaa yhdenmukaisia tuloksia Matlab simulaatioiden kanssa ja pystyy toimimaan yleiskäyttöisen suorittimen laskentateholla