New Approach of Indoor and Outdoor Localization Systems

Accurate determination of the mobile position constitutes the basis of many new applications. This book provides a detailed account of wireless systems for positioning, signal processing, radio localization techniques (Time Difference Of Arrival), performances evaluation, and localization applications. The first section is dedicated to Satellite systems for positioning like GPS, GNSS. The second section addresses the localization applications using the wireless sensor networks. Some techniques are introduced for localization systems, especially for indoor positioning, such as Ultra Wide Band (UWB), WIFI. The last section is dedicated to Coupled GPS and other sensors. Some results of simulations, implementation and tests are given to help readers grasp the presented techniques. This is an ideal book for students, PhD students, academics and engineers in the field of Communication, localization & Signal Processing, especially in indoor and outdoor localization domains

Target identification theory for synthetic aperture radar images using physics-based signatures

Thesis (Sc.D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1999.Includes bibliographical references (p. 217-221).by Chen-Pang Yeang.Sc.D

Probing quantum devices with radio-frequency reflectometry

Many important phenomena in quantum devices are dynamic, meaning that they cannot be studied using time-averaged measurements alone. Experiments that measure such transient effects are collectively known as fast readout. One of the most useful techniques in fast electrical readout is radio-frequency reflectometry, which can measure changes in impedance (both resistive and reactive) even when their duration is extremely short, down to a microsecond or less. Examples of reflectometry experiments, some of which have been realized and others so far only proposed, include projective measurements of qubits and Majorana devices for quantum computing, real-time measurements of mechanical motion, and detection of non-equilibrium temperature fluctuations. However, all of these experiments must overcome the central challenge of fast readout: the large mismatch between the typical impedance of quantum devices (set by the resistance quantum) and of transmission lines (set by the impedance of free space). Here, we review the physical principles of radio-frequency reflectometry and its close cousins, measurements of radio-frequency transmission and emission. We explain how to optimize the speed and sensitivity of a radio-frequency measurement and how to incorporate new tools, such as superconducting circuit elements and quantum-limited amplifiers into advanced radio-frequency experiments. Our aim is threefold: to introduce the readers to the technique, to review the advances to date, and to motivate new experiments in fast quantum device dynamics. Our intended audience includes experimentalists in the field of quantum electronics who want to implement radio-frequency experiments or improve them, together with physicists in related fields who want to understand how the most important radio-frequency measurements work

The 1992 4th NASA SERC Symposium on VLSI Design

Papers from the fourth annual NASA Symposium on VLSI Design, co-sponsored by the IEEE, are presented. Each year this symposium is organized by the NASA Space Engineering Research Center (SERC) at the University of Idaho and is held in conjunction with a quarterly meeting of the NASA Data System Technology Working Group (DSTWG). One task of the DSTWG is to develop new electronic technologies that will meet next generation electronic data system needs. The symposium provides insights into developments in VLSI and digital systems which can be used to increase data systems performance. The NASA SERC is proud to offer, at its fourth symposium on VLSI design, presentations by an outstanding set of individuals from national laboratories, the electronics industry, and universities. These speakers share insights into next generation advances that will serve as a basis for future VLSI design

Compensation Effect of Quasi-Inverse Filter (QIF) on Frequency Characteristic Distortion in Wideband Systems

High-speed wireless communication systems have attracted much attention in recent years. To achieve a high-speed wireless communication system that utilizes an ultra-wide-frequency band, a broad-band antenna is required. However, it is difficult to abtain an antenna that has uniform characteristics in a broad frequency band. Moreover, propagation characteristics are distorted in a multi-path environment. Thus, the communication quality tends to degrade due to the distortion in the frequency characteristics of the wideband communication system. This paper proposes a quasi-inverse filter(QIF) to improve the compensation effect for the transmitter antenna. Furthermore, we propose a method that employs the newly developed QIF that compensates for frequency characteristic distortion. We evaluate different configurations for the compensation system employing a pre-filter and post-filter in the wideband communication system. The effectiveness of the QIF in the case of severe distortion is verified by computer simulation. The proposed method is applied to a discmonopole antenna as a concrete example of a broadband antenna, and the compensation effect for the antenna is indicated

Television broadcast from space systems: Technology, costs

Broadcast satellite systems are described. The technologies which are unique to both high power broadcast satellites and small TV receive-only earth terminals are also described. A cost assessment of both space and earth segments is included and appendices present both a computer model for satellite cost and the pertinent reported experience with the Japanese BSE

Low-THz Automotive 3D Imaging Radar

This thesis lays out initial investigations into the 3D imaging capabilities of low-THz radar for automotive applications. This includes a discussion of the state of the art of automotive sensors, and the need for a robust, high-resolution imaging system to compliment and address the short-comings of these sensors. The unique capabilities of low-THz radar may prove to be well-suited to meet these needs, but they require 3D imaging algorithms which can exploit these capabilities effectively. One such unique feature is the extremely wide signal bandwidth, which yields a fine range resolution. This is a feature of low-THz radar which has not been discussed or properly investigated before, particularly in the context of generating the 3D position of an object from range information. The progress and experimental verification of these algorithms with a prototype multi-receiver 300GHz radar throughout this project are described; progressing from simple position estimation to highly detailed 3D radar imaging. The system is tested in a variety of different scenarios which a vehicle must be able to navigate, and the 3D imaging radar is compared with current automotive demonstrators experimentally

A forecast of space technology, 1980 - 2000

The future of space technology in the United States during the period 1980-2000 was presented, in relation to its overall role within the space program. Conclusions were drawn and certain critical areas were identified. Three different methods to support this work were discussed: (1) by industry, largely without NASA or other government support, (2) partially by industry, but requiring a fraction of NASA or similar government support, (3) currently unique to space requirements and therefore relying almost totally on NASA support. The proposed work was divided into the following areas: (1) management of information (acquisition, transfer, processing, storing) (2) management of energy (earth-to-orbit operations, space power and propulsion), (3) management of matter (animate, inanimate, transfer, storage), (4) basic scientific resources for technological advancement (cryogenics, superconductivity, microstructures, coherent radiation and integrated optics technology)

Implementation of a X-mode multichannel edge density profile reflectometer for the new ICRH antenna on ASDEX Upgrade

Ion cyclotron resonance heating (ICRH) is one of the main heating mechanisms for nuclear fusion plas- mas. However, studying the effects of ICRH operation, such as power coupling efficiency and convective transport, requires the measurement of the local edge plasma density profiles. Two new three-strap an- tennas were designed to reduce tungsten impurity release during operation, and installed on ASDEX Upgrade. One of these ICRH antennas embedded ten pairs of small microwave pyramidal horn anten- nas. In this thesis, a new multichannel X-mode microwave reflectometry diagnostic was developed to use these embedded antennas to simultaneously measure the edge electron density profiles in front of the bottom, middle and top regions of the radiating surface of the ICRH antenna. Microwave reflectome- try is a radar technique that measures the round trip delay of probing waves that are reflected at specific cutoff layers, depending on the probing wave frequency, plasma density and local magnetic field. This diagnostic uses a coherent heterodyne quadrature detection architecture and probes the plasma in the range 40-68 GHz to measure plasma edge electron densities up to 2×1019 m-3, with magnetic fields between 1.85 T and 2.7 T, and a repetition interval as low as 25 μs. This work details the implementa- tion and commissioning of the diagnostic, including the calibration of the microwave hardware and the analysis of the raw reflectometry measurements. We study the automatic initialization of the X-mode upper cutoff measurement, which is the main source of error in X-mode density profile reconstruction. Two first fringe estimation algorithms were developed: one based on amplitude and spectral information and another using a neural network model to recognize the first fringe location from spectrogram data. Kalman filters are used to improve radial measurement uncertainty to less than 1 cm. To validate the diagnostic, we compared the density profile measurements with other electron density diagnostics on ASDEX Upgrade, and observed typical plasma phenomena like the L-H transition and ELM activity. The experimental density profile results were used to corroborate ICRH power coupling simulations under different gas puffing conditions and to observe poloidal convective transport during ICRH operation