Field programmable gate array based multiple input multiple output transmitter

MIMO is an advanced antenna technology compared to Single Input Single output (SISO), Multiple Input Single Output (MISO), and Single Input Multiple Output (SIMO) and is used to obtain high data rate in the system. Multiple-Input Multiple-Output (MIMO) systems have at least two transmitting antennas, each generating unique signals. However some applications may require three, four, or more transmitting devices to achieve the desired system performance. This thesis describes a comparison between different approaches like the microcontroller, ASICs and the FPGA available in the market for baseband signal generation. It also describes the design of a scalable MIMO transmitter, based on field programmable gate array (FPGA) technology that was selected among the processors due to its capability to provide reconfigurable hardware and software. Each module of the MIMO transmitter contains a FPGA, and associated digital-to-analog converters, I/Q modulators, and RF amplifiers needed to power one of the MIMO transmitters. The system is designed to handle up to a 10 Mbps data rate, and transmit signals in the unlicensed 2.4 GHz ISM band --Abstract, page iii

Dissertation review on a new control perspective on phase locked loops

The technique of phase-locked loop (PLL), an essential means for online frequency detection of incoming signal, which is widely used in our modern day communication system. PLL is traditionally viewed as a non-linear feedback control loop that will automatically locks the adjustable frequency of a local oscillator in reference to the incoming signal. However, the classic PLL technique has reviewed its first sign of weakness, limited convergence performance and complex in structure implementation. To overcome these weaknesses and to improve its current performance, the final outcome of the project is to bring about a better developed idea in frequency estimation compared with the present PLL technique.A new approach known as adaptive observer method, which allowed direct estimation on frequency of an incoming signal, was recently proposed in the control literature. The underlying principle of this project is to investigate the possible use of adaptive observer method for detecting frequencies directly from any sinusoidal signals, and as well as to improve its ability in terms of better performance. Both classic PLL technique and adaptive observer method are compared through several aspects, for instance theoretical study and software simulation. However, due to adaptive observer method is significantly over-performed the PLL technique at the stage of simulation

Noise Weighting in the Design of {\Delta}{\Sigma} Modulators (with a Psychoacoustic Coder as an Example)

A design flow for {\Delta}{\Sigma} modulators is illustrated, allowing quantization noise to be shaped according to an arbitrary weighting profile. Being based on FIR NTFs, possibly with high order, the flow is best suited for digital architectures. The work builds on a recent proposal where the modulator is matched to the reconstruction filter, showing that this type of optimization can benefit a wide range of applications where noise (including in-band noise) is known to have a different impact at different frequencies. The design of a multiband modulator, a modulator avoiding DC noise, and an audio modulator capable of distributing quantization artifacts according to a psychoacoustic model are discussed as examples. A software toolbox is provided as a general design aid and to replicate the proposed results.Comment: 5 pages, 18 figures, journal. Code accompanying the paper is available at http://pydsm.googlecode.co

50-250MHZ ?S DLL for Clock Synchronization

Ph.DDOCTOR OF PHILOSOPH

Borman Expressway Point-to-Point Wireless Modem

The Federal Highway Administration has a nationwide allocation of five frequency pairs in the 220-222 MHz Narrowband Radio Services band which are intended for application in Intelligent Transportation Systems. These frequencies are available for use by state DOTs (subject to FHWA approval) and provide an attractive solution for certain low to medium bit rate data communications applications. However, given the limited bandwidth available in these channels, very efficient modems will be required to make maximum beneficial use of this resource. The goal of this project was to design, field test, and deploy a digital radio which uses the 220-222 MHz spectral allocation and is suitable for stationary point-to-point data communications applications. The target application for this project was the control (pan, tilt, and zoom) of a video camera located at the interchange of I-65 and the Borman Expressway. The wireless link extends from the camera location to the traffic operations center (approximately 1.5 miles). There were three main tasks needed to produce a deployable modem: 1) interface circuitry was required between the 220 MHz modem and the camera control keypad and the camera pan/tilt/zoom receiver, 2) the fabrication of a compact and rugged transmitter was required, and 3) the fabrication of a compact and rugged receiver was required. The receiver size constraints were more exacting than those of the transmitter as the receiver is deployed in a roadside cabinet, while the transmitter is deployed in the traffic management center. The work plan was divided into a set of twelve tasks. The 220 MHz modem can serve INDOT as a general purpose link for low to medium rate data communications in a wide variety of applications. The most significant issue outstanding with regard to widespread implementation of the technology is the mass production cost and the availability of a reliable source of production versions of the device. Efforts are continuing at both Purdue and Ohio State toward further simplifications aimed at complexity reduction in the receiver. As topics for further study, the following should be considered: 1) a detailed cost/benefit analysis should be made comparing the 220 MHz technology to other alternative technologies, and 2) a preliminary design study of interoperability issues should be performed for the 220 MHz technology in transportation applications

Custom Integrated Circuits

Contains reports on ten research projects.Analog Devices, Inc.IBM CorporationNational Science Foundation/Defense Advanced Research Projects Agency Grant MIP 88-14612Analog Devices Career Development Assistant ProfessorshipU.S. Navy - Office of Naval Research Contract N0014-87-K-0825AT&TDigital Equipment CorporationNational Science Foundation Grant MIP 88-5876

34th Midwest Symposium on Circuits and Systems-Final Program

Organized by the Naval Postgraduate School Monterey California. Cosponsored by the IEEE Circuits and Systems Society. Symposium Organizing Committee: General Chairman-Sherif Michael, Technical Program-Roberto Cristi, Publications-Michael Soderstrand, Special Sessions- Charles W. Therrien, Publicity: Jeffrey Burl, Finance: Ralph Hippenstiel, and Local Arrangements: Barbara Cristi

LISA Metrology System - Final Report

Gravitational Waves will open an entirely new window to the Universe, different from all other astronomy in that the gravitational waves will tell us about large-scale mass motions even in regions and at distances totally obscured to electromagnetic radiation. The most interesting sources are at low frequencies (mHz to Hz) inaccessible on ground due to seismic and other unavoidable disturbances. For these sources observation from space is the only option, and has been studied in detail for more than 20 years as the LISA concept. Consequently, The Gravitational Universe has been chosen as science theme for the L3 mission in ESA's Cosmic Vision program. The primary measurement in LISA and derived concepts is the observation of tiny (picometer) pathlength fluctuations between remote spacecraft using heterodyne laser interferometry. The interference of two laser beams, with MHz frequency difference, produces a MHz beat note that is converted to a photocurrent by a photodiode on the optical bench. The gravitational wave signal is encoded in the phase of this beat note. The next, and crucial, step is therefore to measure that phase with µcycle resolution in the presence of noise and other signals. This measurement is the purpose of the LISA metrology system and the subject of this report

Power Management ICs for Internet of Things, Energy Harvesting and Biomedical Devices

This dissertation focuses on the power management unit (PMU) and integrated circuits (ICs) for the internet of things (IoT), energy harvesting and biomedical devices. Three monolithic power harvesting methods are studied for different challenges of smart nodes of IoT networks. Firstly, we propose that an impedance tuning approach is implemented with a capacitor value modulation to eliminate the quiescent power consumption. Secondly, we develop a hill-climbing MPPT mechanism that reuses and processes the information of the hysteresis controller in the time-domain and is free of power hungry analog circuits. Furthermore, the typical power-performance tradeoff of the hysteresis controller is solved by a self-triggered one-shot mechanism. Thus, the output regulation achieves high-performance and yet low-power operations as low as 12 µW. Thirdly, we introduce a reconfigurable charge pump to provide the hybrid conversion ratios (CRs) as 1⅓× up to 8× for minimizing the charge redistribution loss. The reconfigurable feature also dynamically tunes to maximum power point tracking (MPPT) with the frequency modulation, resulting in a two-dimensional MPPT. Therefore, the voltage conversion efficiency (VCE) and the power conversion efficiency (PCE) are enhanced and flattened across a wide harvesting range as 0.45 to 3 V. In a conclusion, we successfully develop an energy harvesting method for the IoT smart nodes with lower cost, smaller size, higher conversion efficiency, and better applicability. For the biomedical devices, this dissertation presents a novel cost-effective automatic resonance tracking method with maximum power transfer (MPT) for piezoelectric transducers (PT). The proposed tracking method is based on a band-pass filter (BPF) oscillator, exploiting the PT’s intrinsic resonance point through a sensing bridge. It guarantees automatic resonance tracking and maximum electrical power converted into mechanical motion regardless of process variations and environmental interferences. Thus, the proposed BPF oscillator-based scheme was designed for an ultrasonic vessel sealing and dissecting (UVSD) system. The sealing and dissecting functions were verified experimentally in chicken tissue and glycerin. Furthermore, a combined sensing scheme circuit allows multiple surgical tissue debulking, vessel sealer and dissector (VSD) technologies to operate from the same sensing scheme board. Its advantage is that a single driver controller could be used for both systems simplifying the complexity and design cost. In a conclusion, we successfully develop an ultrasonic scalpel to replace the other electrosurgical counterparts and the conventional scalpels with lower cost and better functionality