Reliable Sensor Location for Object Positioning and Surveillance via Trilateration

Indoor Positioning for Smartphones Using Asynchronous Ultrasound Trilateration

Modern smartphones are a great platform for Location Based Services (LBS). While outdoor LBS for smartphones has proven to be very successful, indoor LBS for smartphones has not yet fully developed due to the lack of an accurate positioning technology. In this paper we present an accurate indoor positioning approach for commercial off-the-shelf (COTS) smartphones that uses the innate ability of...

Asynchronous Ultrasonic Trilateration for Indoor Positioning of Mobile Phones

In this paper we discuss how the innate ability of mobile phone speakers to produce ultrasound can be used for accurate indoor positioning. The frequencies in question are in a range between 20 and 22 KHz, which is high enough to be inaudible by humans but still low enough to be generated by today’s mobile phone sound hardware. Our tests indicate that it is possible to generate the given range ...

An efficient approach for trilateration in 3D positioning

Trilateration is a common operation to find the object location using its distances or range measurements to three other known points or stations. Traditionally, this problem has been solved either by algebraic or numerical methods. These methods involve long and complex geometric computations which are usually implemented in software. An approach that avoids this complexity is proposed here. S...

Reliable Motion Detection, Location and Audit in Surveillance Video

The review of video captured by fixed surveillance cameras is a time consuming, tedious, expensive and potentially unreliable human process, but of very high evidentiary value. Two key challenges stand out in such a task; ensuring that all motion events are captured for analysis, and demonstrating that all motion events have been captured so that the evidence survives being challenged in court....

Beyond Trilateration: GPS Positioning Geometry and Analytical Accuracy