A study on the implementation of a 3-dimensional positioning system on indoor environments

In this paper, we implemented a three dimensional positioning system with consideration of indoor wireless channel. A commercial modules are used for mobile and fixed node which is a product of German company Nanotron Co. Chirp spread spreading is adopted as modulation scheme to improve the ranging resolution and the module satisfies the IEEE standard 802.15.4a. The distance computation is based on received signal strength(RSS) levels and trilateration method. A testbed was set up to measure and compare the positioning estimation error of the used algorithm. The experiments results showed that the accuracy of location estimation was satisfied with the proposed method as much as 1m distance error in a wireless environment in an office building. We also propose a novel equation for distance estimation of three dimensional ranging system.