A novel wideband dynamic directional indoor channel model based on a Markov process

This document is made available in accordance with publisher policies. Please cite only the published version using the reference above. Full terms of use are available

Polar Environmental Monitoring

The present and projected benefits of the polar regions were reviewed and then translated into information needs in order to support the array of polar activities anticipated. These needs included measurement sensitivities for polar environmental data (ice/snow, atmosphere, and ocean data for integrated support) and the processing and delivery requirements which determine the effectiveness of environmental services. An assessment was made of how well electromagnetic signals can be converted into polar environmental information. The array of sensor developments in process or proposed were also evaluated as to the spectral diversity, aperture sizes, and swathing capabilities available to provide these measurements from spacecraft, aircraft, or in situ platforms. Global coverage and local coverage densification options were studied in terms of alternative spacecraft trajectories and aircraft flight paths

Meteorological satellites

An overview is presented of the meteorological satellite programs that have been evolving from 1958 to the present, and plans for the future meteorological and environmental satellite systems that are scheduled to be placed into service in the early 1980's are reviewed. The development of the TIROS family of weather satellites, including TIROS, ESSA, ITOS/NOAA, and the present TIROS-N (the third generation operational system) is summarized. The contribution of the Nimbus and ATS technology satellites to the development of the operational-orbiting and geostationary satellites is discussed. Included are descriptions of both the TIROS-N and the DMSP payloads currently under development to assure a continued and orderly growth of these systems into the 1980's

SWEPT-TIME DELAY CROS S -CORRELATION RADAR AT 2 4 / 2 8 GHZ

Radar applications can be found today in many sectors of the industry and the number of implemented systems will keep increasing over time. Detecting and measuring the distance of an object with more accuracy and reliability becomes a complex task as possible interference sources are increasingly being deployed. Frequency-Modulated Continuous-Wave (FMCW) radars, simple and commonly used in the automotive industry, for example, suffer significantly from neighbouring FMCW radars, as they can corrupt each other’s results and produce false positives or limit their ability to detect weaker reflections. This project aims at the improvement of an existing radio channel sounder, as well as transitioning the system into a radar topology for target identification. The modular radar architecture allows the integration of different Radio Frequency (RF) stages present in the research group. The radar implements the Swept-Time Delay Cross-Correlation (STDCC) technique of Pseudo-Noise (PN) sequences, where amplitude and Doppler information can be extracted from multipath components, characterising the radio channel obstacles. The radar parameters can be easily adjusted on-the-fly to the environment being measured. A new RF front-end was developed at 28 GHz using X-MWblocks from X-Microwave, a modular designing and prototyping system for RF products. The baseband sequence generation has been implemented into an all-digital Field-Programmable Gate Array (FPGA) based system and tested in a controlled environment against a Commercial off-the-shelf (COTS) FMCW radar

A Study of DAS delays and their Impact on the Wireless Channels with Application to Indoor Localization

This research evaluates the Distributed Antenna Systems (DAS) introduced delays and their effects on the indoor channel in simulcast situations where the effect of delays is most prevalent. Different simulcast cases that form the basic building blocks are analyzed to form an understanding of the problem. Two case studies of important indoor environments are presented. Importance of improving ray tracing simulations to include propagation and DAS delays is highlighted. The paper also introduces a DAS element representation and delay mapping model and explores techniques of engineering DAS delays to optimize location estimation by ranging and RF fingerprinting to achieve E911 mandated accuracy. A brief description is introduced for a Software Defined Radio (SDR) implementation of a Correlation Channel Sounder and the possible application of channel sounding for indoor DAS. The paper suggests procedures to produce a full DAS delay profile and ways to optimize it for location estimation

Uncertainty Analysis Methodology for Measurements of Dynamic Millimeter-Wave Channels

Quantification of uncertainties in the results of channel sounding measurements is important for their interpretation and further usage. In this paper, a novel uncertainty analysis methodology to quantify uncertainties of condensed parameters in measurements of dynamic millimeter-wave channels is presented. The bandwidth limitation and multipath threshold are identified as important impairments. Therefore, the methodology provides three uncertainty metrics for condensed parameters, namely a standard uncertainty to quantify the impact of random variations; a bias due to the multipath threshold; and a total bias including the impact of the bandwidth limitation. These uncertainty metrics are highly channel dependent. Therefore, the proposed methodology creates reference channels, which are representative of corresponding measured channels. Hardware and processing impairments are included in the analysis via a Monte Carlo simulation. This results in a general methodology that can quantify uncertainties in both static and dynamic channel measurements of any wideband channel sounder. The methodology is implemented, verified and demonstrated for the TU/e channel sounder, which exemplifies how it can be used. The proposed methodology can improve the analysis, interpretation and reporting of channel measurement results.</p

Technology needs assessment of an atmospheric observation system for tropospheric research missions, part 1

The technology advancements needed to implement the atmospheric observation satellite systems for air quality research were identified. Tropospheric measurements are considered. The measurements and sensors are based on a model of knowledge objectives in atmospheric science. A set of potential missions and attendant spacecraft and sensors is postulated. The results show that the predominant technology needs will be in passive and active sensors for accurate and frequent global measurements of trace gas concentration profiles