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The ionosphere is a region on the Earth's upper atmosphere which extends between 50 km to 1000 km from the ground. It is a layer that consists gases which are ionized by solar radiation. Solar radiation and incident angle of the Sun is important to understand how the Ionosphere affects the radio waves. Total Electron Content (TEC) is one of the important parameters that characterizes Ionosphere and...
Uncorrelated samples of GPS carrier phase can be measured at a high rate in a tracking loop or via open-loop tracking. The high-rate carrier phase estimates from both approaches are expected to be equivalent to each other. However, the practical implementation of the tracking loop could cause a small difference in the measurement, which may become substantial when there is residual or transient error...
Phasor Measurement Units (PMUs) provide time synchronized electrical measurements at many nodes across the power grid. This wide area time synchronization is made possible via GPS time transfer. Unfortunately, the GPS civilian signal is weak and vulnerable to signal interferences such as jamming and meaconing. As such, the GPS-based time synchronization of PMUs may be a potential point of entry for...
We devise a centralized node localization algorithm, which relies on linearization and employs the orthogonal matching pursuit algorithm at its core, albeit with modifications and additional steps in order to address the localisation problem. The main feature of the algorithm is that it can determine the position of more than one simultaneously transmitting unknown nodes. This renders it generic and...
Many Vehicular Ad Hoc Networks (VANETs) applications require the vehicle's location information to be available at anytime and anywhere within the network. Vehicle-to-vehicle (V2V) communication allows the exchange of mobility data, which includes position, speed and heading information, that can be used for location estimation. However, if the exchanged mobility data contains invalid or wrong information,...
Recommending points of interests (POIs) is drawing more attention to meet the growing demand for tours. A POI's quality (sightseeing value) estimation is one of the important challenges. In contrast to conventional studies of ranking POIs based on user behavior analysis, in this paper, we propose methods of quality estimation by analyzing geosocial images. Our approach estimates the sightseeing value...
The accuracy estimation of positioning system operation for autonomous underwater vehicle (AUV) based on using of single hydro acoustic beacon transported by autonomous surface vehicle (ASV) is discussed. The accuracy research is performed for two navigation algorithms which used information about distance to a single mobile beacon and data from the AUV onboard reckoning system. The first algorithm...
This paper presents a technology for three real time applications of prime importance such as post disaster infrastructure-damage assessment using GPS, estimation of building strength and building movement. GPS sensor nodes installed on building roof-top, provides with relative position information from both pre- and post-earthquake periods & are superimposed on GIS. The changes are used for damage...
Many passengers have expressed frustration in waiting for public bus endlessly without knowing the estimated arrival time. In many developing countries, requiring bus operators to invest in the installation of a GPS unit on every bus in order to track the bus location and subsequently predicting the bus arrival time can be costly. This paper proposes passenger-assisted sharing of bus location to provide...
Extended Kalman filter (EKF) solution for attitude and heading estimation was proposed with code phase GPS measurements aiding the micro electro mechanical systems (MEMS) Inertial Measurement Unit (IMU). The estimation was carried out assuming GPS update rates of 1, 4, 5 and 10 Hz while the IMU update rate was assumed to be 40 Hz. GPS outage durations of 20 s and 15 s were considered for a total simulation...
Wrist-worn wearable fitness devices, such as FitBit and Apple Watch, have become popular in recent years. Runners can use the GPS embedded in these wearable devices to log the route taken during their exercise, providing vital feedback on pace and distance traveled. Unfortunately, continuous polling for GPS data results in a significant adverse impact on device battery life, e.g., many flagship wearables...
One major challenge of relying on Dedicated Short Range Communication (DSRC)-equipped vehicles for high precision cooperative localization is related to the high computational complexity and heavy communication loads of exhaustively considering links to all neighbors regardless of their quality. This paper addresses the problem of selecting the best subset of links to spatial neighbors, considering...
This paper focuses on performance enhancement for stand-alone Global Navigation Satellite System (GNSS) positioning. To speed up the realization of satellite position, a novel technique is proposed for GNSS satellite orbit fast fitting, which contributes to the acquisition of GNSS satellite signal deeply. The ephemeris orbit model is imminent by different fitting algorithms and polynomial interpolation...
Localisation in wireless sensor network is the process of determining the geographical location of the sensor nodes. Conventional localization is space oriented which uses GPS (Global Positioning System) signal to obtain the location information of the nodes. But the GPS signals fail to work in indoor environments, the reason for which it becomes mandatory to opt for terrestrial localisation. The...
Localization as a fundamental issue has a challenge in wireless sensor networks (WSNs). Many approaches have been proposed to solve the inaccurate node localization. Among range-free algorithms, DV-Hop (Distance Vector-hop) is a well-known localization algorithm that utilizes of hop-distance estimation to locate sensor nodes. This has lead positioning accuracy is limited. In this paper, an improved...
The multi-path phenomenon is one of the main causes of error in Direction Of Arrival Estimation systems which are located in a complex environment. The received signal in this environment consists of Line Of Sight (LOS) and multi-path components which are delayed versions of the LOS signal with the amplitude and the phase depending on the path length. In order to eliminate the multi-path signal, it...
A person's routine incorporates the frequent and regular behaviour patterns over a time scale, e.g. daily routine. In this work we present a method for unsupervised discovery of a single person's daily routine within an indoor environment using a static depth sensor. Routine is modelled using top down and bottom up hierarchies, formed from location and silhouette spatio-temporal information. We employ...
This paper presents a method for estimating the orientation and position of an unmanned aerial vehicle (UAV), through processing information provided by a RGB-D sensor and an inertial measurement unit (IMU) in order to inspect predefined points in an indoor environment. A fusion filter is implemented to correct the existing drift position and orientation errors on a commercial AR.Drone quadrotor model...
With growing road traffic, it becomes essential to predict the travel time of road travelers well ahead of their travel to avoid traffic mismanagement. Vehicular Adhoc Network (VANET) infrastructure is an ideal solution for such requirements. VANET uses Road Side Units (RSU) that remain as the primary and critical source to predict the traffic in any road. This paper proposes an Optimized RSU based...
In which way may an application switch instantly and reliably between an indoor and an outdoor positioning provider as a user enters and exits buildings? In this work we present a robust switching algorithm, utilizing the dynamic accuracy estimation of each position provider as a reliability indication. Our algorithm offers a fast automatic switch between the indoor and the outdoor provider, in a...
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