Performance Evaluation of High Sensitivity GNSS Techniques in Indoor, Urban and Space Environments (original) (raw)

Multi-GNSS Dynamic High Precision Positioning in Urban Environment

Proceedings of the 30th International Technical Meeting of The Satellite Division of the Institute of Navigation (ION GNSS+ 2017), 2017

received his M.S. degree in Industrial Systems Engineering, from the Universidad Carlos III de Madrid, Spain, in 2014. He is currently working as a Radio Navigation Engineer at the European Space Agency and employed by Universitat Autònoma de Barcelona. He is working on the performance assessment of Real Time Precise Point Positioning (PPP) for mobile user with Professional (Dual-Frequency) and Mass-Market (Single-Frequency) Receivers using single and multi-GNSS constellations. In addition he is working with performance analysis tools in order to characterize the future GNSS scenario, especially in urban environments but also in rural-open sky. José V. Perello Gisbert received his M.S. degree in Telecommunications Engineering from the Universidad Politécnica de Valencia, Spain, in 2002. He is currently working in the European Space Agency (ESTEC, the Netherlands) as Galileo Evolutions system performance engineer. Previously he worked for Galileo performance characterization (using GNSS receivers) during In Orbit Validation (IOV), experimentation phase and satellites in orbit testing. He is also managing GNSS R&D activities. Since 2005 he has been supporting the Galileo project. J.A. Garcia-Molina is a Radio Navigation Engineer at the European Space Agency (Noordwijk, the Netherlands), where he leads several R&D activities on GNSS receiver technology and ground and space applications. His main research interests include signal processing, estimation theory, GNSS receivers and signals, and cloud positioning applications.

Analysis of the Accuracy of Indoor GNSS Measurements and Positioning Solution

High sensitivity GNSS receivers tracking weak signals have been developed for indoor applications and to operate in urban canyons. They allow to track GNSS satellites when the signal is strongly attenuated by structures, walls and buildings. The increase in sensitivity and the fact that it is not possible to know a priori the conditions of the received signal (affected by strong multipath) makes unsafe to use the available observations without error models and a preliminary integrity check on the data. In these difficult conditions, signals may be strongly attenuated and reflected by one or more structures surrounding the receiver. When operating indoor or in urban canyon conditions the signal is strongly affected by multiple reflections generated by the surroundings. The received signal is distorted by many reflected components. Direct signals may be weaker than reflected/diffracted ones or may not be usable at all. A processing strategy optimized for indoor conditions is necessary...

Assessment of GNSS signal acquisition sensitivities for indoor and urban scenarios

2010 IEEE 21st International Symposium on Personal, Indoor and Mobile Radio Communications Workshops, 2010

Signals of Galileo and modernized GPS will provide a new possibility in the next five years that will enable to overcome current limitations in indoor/urban environments. With modernization of GPS L1C, L2C, L5 and full deployment of Galileo, E1b, c, E5a, b, E6 signals will be available. It is therefore of major interest to assess new capabilities of the incoming GNSS signals and their potential for the location based and emergency services in GNSS enabled mobile phone or PDA. In this paper, the acquisition performance of the available GPS and Galileo signals are evaluated related to the receiver sensitivity and the computational complexity within different scenarios. By using a weighting evaluation, we show that GPS L5 pilot signal gives the optimum performance among available signals.

Noise Analysis of High Sensitivity GNSS-Receivers for Direct Geo-Referencing of Multi-Sensor Systems

International Association of Geodesy (IAG) Commission 4 (Positioning and Application) Symposium, 2016

Stationary terrestrial laser scanning (TLS) provides a 3D point cloud in a local sensor-defined coordinate system. The transformation parameters of such point clouds to a global coordinate system are generally obtained by pre-surveyed control points with known geodetic datum. To improve this procedure, a direct geo-referencing method of a multi-sensor system with 3D position sensors has been developed at the Geodetic Institute Hannover. The current approach uses two small scaled and light weighted, high sensitivity GNSS-receivers of type Ublox EVK-M8T and Ashtech L1 antennas as 3D position sensors. These sensor types are used to reduce weight and equipment costs. They are mounted with a mutual distance (baseline) of 1 m on top of the laser scanner that rotates about its vertical axis. The analysis of the trajectories of the 3D GNSS-points and the estimation of the transformation parameters are based on a recursive filter approach in form of an extended Kalman Filter (EKF). With the EKF algorithm optimal results can only be provided, if the system noise is normally distributed with known variance covariance matrix and without correlations over time. That means the model requires white noise. Unfortunately, this assumption is not sufficient in our processing approach due to the stochastically time-correlated state vector. Former studies revealed that the analysis of short kinematic time series (15 minutes) yields to insufficiencies regarding, e. g. the determination of the auto-correlation. Therefore, long-term static time series (up to 7 days) of four identical high sensitivity GNSS-receivers were acquired on a zero baseline approach. The reference antenna and receiver of the Institut für Erdmessung (IfE) are used as benchmark to evaluate and study proper parameters for the EKF parameter estimation and the direct geo-referencing parameters, respectively. This contribution presents the noise analysis of the impact and the determination of statistical quality measures for improving the EFK parameter estimation. We will critically discuss results of our benchmark test of high sensitivity GNSS-receivers of type Ublox EVK-M8T. The noise analysis is based on a zero baseline approach. Important key parameters are e.g. the carrier phase stability and the overall acceptable noise level. The Allan deviation helps to characterize the process noise for long time series with respect to short time series, as they are used in typically MSS approaches for direct geo-referencing. In addition, first results of kinematic experiments are presented and critically compared to the static derived solutions by their individual uncertainty budget.

Monitoring system using low cost GNSS sensors: first experiments and performance evaluation

2017

This work aims to assess the possibility to use a low cost GNSS instrumentation for structural monitoring purposes. Under the assumption that about one centimeter can be the magnitude of the displacements that we aim to detect, several instrumentations were compared at different baseline distances. All the tests have been performed considering one week of observations. Different observing session time spans have been considered, ranging from 1 hour to 24 hours. Tests demonstrate that by using a single frequency receiver is not possible to achieve the requested precision for baselines longer than a km, at least if observing sessions shorter than 6 hours are needed. Nevertheless, for a baseline within a hundred meters is possible to achieve effective precisions by using a couple of low cost stations also for observing sessions of one hour. The only configuration which does not respect such performances is the one using the default "patch" antennas that we discourage for prec...

Feasibility of Consumer Grade GNSS Receivers for the Integration in Multi-Sensor-Systems

Sensors, 2020

Various GNSS applications require low-cost, small-scale, lightweight and power-saving GNSS devices and require high precision in terms of low noise for carrier phase and code observations. Applications vary from navigation approaches to positioning in geo-monitoring units up to integration in multi-sensor-systems. For highest precision, only GNSS receivers are suitable that provide access to raw data such as carrier phase, code ranges, Doppler and signal strength. A system integration is only possible if the overall noise level is known and quantified at the level of the original observations. A benchmark analysis based on a zero baseline is proposed to quantify the stochastic properties. The performance of the consumer grade GNSS receiver is determined and evaluated against geodetic GNSS receivers to better understand the utilization of consumer grade receivers. Results indicate high similarity to the geodetic receiver, even though technical limitations are present. Various stochas...

Spaceborne GNSS-Receiving System Performance Prediction and Validatio

Spaceborne high-end geodetic-type dual-frequency Global Navigation Satellite System (GNSS) receivers have become an enabling technology for contemporary earth observation missions in Low-Earth Orbits (LEO). Such receivers deliver measurements for space vehicle Precise Orbit Determination (POD) with position accuracy of a few centimeters to geo-locate the measurements taken by other sensors. Roughly speaking, the more precise an earth-observation instrument, the more accurate its position must be determined in order to be able to produce accurate measurement maps. In addition, real-time positioning, accurate within tens of meters - a byproduct of POD-receivers - performed for internal purposes, readily supports the Attitude and Orbit Control Subsystem (AOCS) of the host Spacecraft (S/C). While the notion of recurrence and off-the-shelf availability is reflected in customer price and delivery schedule expectations, POD-receivers are typically procured according to mission specificatio...

Experimental Validation of a High Precision GNSS System for Monitoring of Civil Infrastructures

Sustainability

In recent years, Global Navigation Satellite System (GNSS) technologies, which take full advantage of both real-time kinematic (RTK) and precise point positioning (PPP), managed to reach centimeter-level positioning accuracy with ambiguity resolution (AR) quick convergence techniques. One great advantage over traditional structural health monitoring (SHM) systems is that GNSS technologies will be functional in disaster management situations, when terrestrial communication links become unavailable. In this study, a multi-GNSS system, based on GPS and Galileo constellations and exploiting advanced RTK and PPP-AR technologies with update rate of 100 Hz is tested on two benchmark structures as an SHM system. The first case study served as a baseline to outline the methodology: first, a setup phase of the instrumentation, then a signal processing phase and last, the validation of the results. The methodology was then applied to a real-case scenario, in which the GNSS was tested on a road...