Position Localization for Non Ultra-wideband Devices

The high-frequency, broad-spectrum properties of the UWB (ultra-wide bandwidth) communications protocol enable very accurate, e.g., millimeter-level, spatial and directional localization of devices. The high-precision localization ability of UWB enables fine-grained interactions with devices, e.g., the ability to send commands to specific devices when multiple devices are present in a space. This disclosure describes techniques to bootstrap precise positioning on non-UWB devices, such that UWB-style, fine-grained interactions are enabled even on non-UWB devices. The techniques leverage the presence of two or more UWB-enabled devices, e.g., one on a stationary device and another on a wearable device (or other non-stationary device), to precisely locate non-UWB devices

Prague's Emission Fourier Transform Microwave Spectrometer - Design and Preliminary Results

The design, performance and operation of the high resolution microwave spectrometer are described. The spectrometer is based on the Fabry-Perot resonator supplemented by a pulsed supersonic nozzle for adiabatic cooling of the sample. The spectrometer’s high sensitivity and resolution are demonstrated by several examples

FlexTDOA : Robust and Scalable Time-Difference of Arrival Localization Using Ultra-Wideband Devices

In this paper, we propose FlexTDOA, an indoor localization method using ultra-wideband (UWB) radios, and we demonstrate its performance in a functional system. Our method uses time-difference of arrival (TDOA) localization so that the user device remains passive and is able to compute its location simply by listening to the communication between the fixed anchors, ensuring the scalability of the system. The anchors communicate using a custom and flexible time-division multiple-access (TDMA) scheme in which time is divided in slots. In each time slot, one anchor interrogates one or more anchors which respond in the same slot. The anchors do not need to have their clocks synchronized. We implemented FlexTDOA on in-house designed hardware using a commercial UWB module. We evaluate the localization accuracy of FlexTDOA with different system parameters such as the number of responses, the order of responses, and the number of anchors. We simulate and evaluate the effect of the physical speed of the tag on the choice of optimum system parameters. We also compare FlexTDOA against the classic TDOA approach and range-based localization in a deployment of ten anchors and one tag, both with and without obstructions. Results show that FlexTDOA achieves the highest localization accuracy in most of the scenarios, with up to 38% reduction in the localization error compared to the classic approach.Peer reviewe

Model of broadband metamaterial for microwaves

In this work are presented, results of computer model operation of the structure executed from triangular elements with openings in the center. Results of mathematical calculation of amplitude and phase distribution of an electric field with use of CST Microwave studio are given. Also, calculation of the equivalent index of refraction when passing a plane wave through this structure is given

Ultra Wideband Preliminaries

Non

Elliptic and Hyperbolic Dielectric Lens Antennas in mm-Waves

Dielectric lenses can substantially improve antenna parameters, especially the planarity of radiated waves and the antenna gain. The paper deals with their application in millimeter-wave band. The main goal concerns the introduction of characteristics and differences between the most commonly used types of dielectric lens antennas, i.e. elliptic and hyperbolic. Their particular features as well as behavior of radiating systems incorporating the lenses are investigated. Specific features of these lenses are discussed for both, near-field and farfield based on simulation and measurement results

Evaluation of Ultra-Wideband Position Localization for an Indoor Office Environment

Recently, significant improvements have been made in the area of indoor wireless position estimation. Issues of high power consumption and poor accuracy have stifled business and research initiatives to implement this technology to increase efficiency, save money, and obtain critical information. Investigation was done to determine if Decawave’s DWM1001 technology is capable of tracking workers within an office environment to desk level accuracy for both a static (immobile) and dynamic (mobile) tag. Evaluation was conducted under sparse and dense deployment conditions of anchors. Sparse deployments held 1 anchor per 30 meters squared. Dense deployments held 1 anchor per 15 meters squared. It is concluded that the position of an immobile node can be determined to desk-level accuracy (+/- 20cm) using Decawave’s Ultra-Wideband wireless position estimation. However, in the case of a tag in motion, a more dense system architecture is needed to achieve desk level accuracy. Due to the robustness of ultra-wideband radio waves and a sleep schedule of tag nodes, it is clear that Decawave DWM1001 technology provides many advantages for managing the trade-offs between power, accuracy, and range. Finally, the technology needs improvement in acquiring and interfacing with the position data to be fully capable of tracking a large amount of office workers

An improved indoor positioning based on crowd-sensing data fusion and particle filter

Due to the lack of global positioning system (GPS) signals in some enclosed areas, indoor localization has recently gained significant importance for academics. However, indoor localization has a number of challenges and defects, including accuracy, cost, coverage, and ease of use. This paper explores the integration between the inertial measurement unit (IMU) and Wi-Fi-based received signal strength indicator (RSSI) measurements, demonstrating their combined potential for robust indoor localization. IMUs excel at capturing precise short-term motion dynamics, offering insights into an object’s acceleration and orientation. Conversely, RSSI measurements serve as valuable indicators for relative positioning within indoor environments. By fusing data from these sources, our approach compensates for the inherent weaknesses of each sensor type. To achieve accurate indoor positioning, we employ techniques such as sensor fusion, Wi-Fi fingerprinting, and dead reckoning. Wi-Fi fingerprinting allows us to create a database that maps RSSI measurements to specific locations, while dead reckoning helps mitigate drift and inaccuracies. By combining these methods, we estimate a device’s position with increased precision. Through experimental evaluation, we assess the performance and efficiency of our integrated approach, comparing the estimated path or new location with a predefined reference path. The findings emphasise a significant improvement in accuracy, with the integration of crowd-sensing, particle filtering, and magnetic fingerprinting techniques resulting in a notable increase from 80.49% to 96.32% accuracy

Dish Washer: a Software Tool for RFI Mitigation in Single-dish Radio Astronomical Observations

Radio Frequency Interference is one of the most pressing problems in cm-wavelength world-wide radio astronomy, in particular for single-dish telescope observations. Due to both the increasing abundance of man-made interfering signals and the improved performance of the telescope instrumentation, the impact of RFI at the Italian radio telescope sites is now a major concern, thus strategies for its mitigation are to be applied. Dish Washer is a new software tool for the detection and flagging of RFI in signals collected by single-dish radio telescopes. It implements both interactive flagging and some level of automatic detection of RFI through dedicated algorithms. Its first public release is foreseen as free software under the GNU General Public License