POSITIONING SYSTEM IN INDOOR ENVIRONMENT USING ULTRASOUND TECHNOLOGY

Indoor navigation (navigation in an indoor environment) presents a new challenge in the field of personal navigation systems. Although there are a lot of options available for creation of a navigation system, only a few of them satisfy the requirements of users in terms of accuracy. Systems based on ultrasound (US) technology provide accurate positioning also in an indoor environment, where other navigation techniques (e.g. GNSS) are not available. Properties of the ultrasound (frequency over 20 kHz) combine several advantages that make it an attractive technology for indoor navigation. Its advantages include low financial cost, slow speed of the signal (about 344 m / s, depending on the temperature), low energy demand, low material absorption, or the accurate determination of the relative position (order of 10(-2)m). This paper presents an ultrasound based indoor positioning system developed at the Department of Surveying, Faculty of Civil Engineering SUT in Bratislava.