The Global Positioning System (GPS) is unreliable in dense urban areas, known as canyons, which have tall buildings or narrow streets. This because the block signals from many of satellites. Combining GPS with other Navigation Satellite Systems (GNSS) significantly increases availability direct line-of-sight signals. Modelling used to demonstrate that, although this will enable accurate positioning along direction street, accuracy cross-street be poor unobstructed satellite travel rather...

This second edition of Dr. Grove's book (the original was published in 2008) could arguably be considered a new work. At just under 1,000 pages (including the 11 appendices on DVD), is 80% longer than original. Frankly, word "book" hardly seems adequate, considering wide range topics covered. "Mini-encyclopedia" more appropriate. The hardcover portion comprises 18 chapters, and DVD includes aforementioned plus 20 fully worked examples, 125 problems or exercises (with answers), MATLAB...

Multiple global navigation satellite system (GNSS) constellations can dramatically improve the signal availability in dense urban environments. However, accuracy remains a challenge because buildings block, reflect and diffract signals. This paper investigates three different techniques for mitigating impact of non-line-of-sight (NLOS) reception multipath interference on position without using additional hardware, testing them data collected at multiple sites central London. Aiding solution...

Positioning using the Global System (GPS) is unreliable in dense urban areas with tall buildings and/or narrow streets, known as ‘urban canyons’. This because block, reflect or diffract signals from many of satellites. paper investigates use 3-Dimensional (3-D) building models to predict satellite visibility. To Navigation Satellite (GNSS) performance 3-D models, a simulation has been developed. A few optimized methods improve efficiency for real-time purposes were implemented. Diffraction...

Global Navigation Satellite System (GNSS) shadow matching is a new positioning technique that determines position by comparing the measured signal availability and strength with predictions made using three-dimensional (3D) city model. It complements conventional GNSS can significantly improve cross-street accuracy in dense urban environments. This paper describes how has been adapted to work on an Android smartphone presents first comprehensive performance assessment of matching. Using GPS...

Global navigation satellite system (GNSS) positioning is widely used in land vehicle and pedestrian systems. Nevertheless, urban canyons GNSS remains inaccurate due to building blockages reflections, especially the cross-street direction. Shadow matching a new technique, recently proposed for improving accuracy using 3D model of nearby buildings. This paper presents number advances shadow-matching algorithm. First, algorithm has been developed, interpolating between top-scoring candidate...

This tutorial provides an introduction to navigation using inertial sensors, explaining the underlying principles. Topics covered include accelerometer and gyroscope technology their characteristics, strapdown navigation, attitude determination, integration alignment, zero updates, motion constraints, pedestrian dead reckoning step detection, fault detection.

This paper introduces a weighted context-based step length estimation algorithm for pedestrian dead reckoning. Six contexts are considered: stationary, walking, walking sideways, climbing and descending stairs, running. Instead of computing the based on single context, lengths computed different by context probabilities. provides more robust performance when is uncertain. The proposed part reckoning system which includes procedures detection classification. detects time boundaries using...

The signals available for navigation depend on the environment. To operate reliably in a wide range of different environments, system is required to adopt techniques based environmental contexts. In this paper, an context detection framework proposed, building foundation adaptive system. Different land environments are categorized into indoor, urban, and open-sky how Global Navigation Satellite System (GNSS) positioning performs these environments. Indoor outdoor first detected availability...

Abstract The accuracy of conventional global navigation satellite systems (GNSS) positioning in dense urban areas is severely degraded due to blockage and reflection the signals by surrounding buildings. By using 3D mapping buildings aid GNSS positioning, can be substantially improved. However, performance must balanced against computational load. Here, a likelihood-based 3D-mapping-aided (3DMA) ranging algorithm demonstrated that enables predicted non-line-of-sight (NLOS) contribute...

<h3>Summary</h3> The performance of different filtering algorithms combined with 3D mapping-aided (3DMA) techniques is investigated in this paper. Several single- and multi-epoch were implemented then tested on static pedestrian navigation data collected the City London using a u-blox EVK M8T GNSS receiver vehicle Canary Wharf, London, by trial van Racelogic Labsat 3 front-end. results show that has greater impact mobile positioning than positioning, while 3DMA brings more significant...

A core problem relating to indoor positioning is a lack of prior knowledge the environment. To date, most WiFi–RTT research assumes access points in an This paper provides solution this by using simultaneous localisation and mapping (SLAM) algorithm, pedestrian dead reckoning, which uses inertial sensors smartphone. SLAM algorithm has only been researched one instance at time writing; aims expand exploration problem, particularly relation use outlier detection motion models. For trials, were...

The phase transition in the relaxor ferroelectric lead scandium tantalate, Pb(Sc0.5Ta0.5)O3, is investigated both ordered and partly disordered (Sc, Ta disorder) modifications through technique of hard-mode Raman spectroscopy. vibrational modes for para phase, are assigned to different representations respective groups (Fm3m (Z=2), R3m Pm3m (Z=1) (Z=1)) using usual group-theoretical methods. temperature evolution strong band at 61cm-1 (hard mode) from 102 K 873 K, transitions, namely ferro...

The next generation of navigation and positioning systems must provide greater accuracy reliability in a range challenging environments to meet the needs variety mission-critical applications. No single technology is robust enough these requirements on its own, so multisensor solution required. Although many new methods have been developed recent years, little has done bring them together into robust, reliable, cost-effective integrated system. To achieve this, four key challenges be met:...