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Rapid advances in the area of digital systems is an enabler for ubiquitous computing making devices smaller and smarter and paving the way for an interconnected digital world. The most influential digital technology that has changed the lives of so many people and made the interconnected world a possibility is undoubtedly the development of wireless cellular communications. In the early stages of...
One of the major challenges in indoor positioning systems is the severe multipath environment, leading to undetected direct path (UDP) conditions and large positioning errors. This paper provides the results of measurements and modeling of the effect of bandwidth, path detection threshold and UDP occurrence on multipath parameters in a typical office scenario with various classes of receiver locations,...
A ray optics based statistical multipath channel model has been developed to describe the indoor multipath propagation including the important parameters such as path gain, time-of-arrival, angle-of-arrival and number of multipath components. Development of such a model is crucial for performance evaluation of indoor positioning systems. Based on a comprehensive ray-tracing database obtained on the...
Analysis of the persistency and birth/death of multipath components of the channel impulse response is essential for performance evaluation of indoor geolocation algorithms using indirect paths for ranging. The use of indirect paths via multipath diversity is particularly important for situations where the direct path gets blocked. In this letter, we propose a statistical model for the spatial behavior...
Indoor positioning systems employing high bandwidth (up to ultra-wideband) time-of-arrival methods have attracted a lot of attention recently owing to their potential for precise localization and tracking of personnel or assets inside buildings where the GPS systems fail to operate. However, these systems suffer heavily due to severe multipath in indoor areas, leading to large positioning errors since...
Ultra-wideband (UWB) indoor positioning systems based on time of arrival (TOA) techniques are considered to be the high precision alternatives to those employing received signal strength (RSS) or angle of arrival (AOA) due to their superior time-domain resolution. However, the performance of such systems may easily be degraded by the blockage of the direct path (DP) and occurrence undetected direct...
The performance of ultra-wideband (UWB) indoor positioning systems based on time of arrival (TOA) techniques is generally affected by the density of reference points (RPs), as well as undetected direct path (UDP) conditions. For a fixed number of reference points (RPs), the performance of some indoor positioning algorithms tends to degrade as the size of the area is increased, i.e. the RP density...
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