A Novel Indoor Localization Method Based on Received Signal Strength using Discrete Fourier Transform

Received signal strength (RSS) based indoor localization methods have drawn great attention due to its low cost and ease of deployment in recent years. How to predict indoor received signal strength in a certain position is the chief difficulty. Existing two categories of location estimation techniques have respective disadvantages. This paper analyzes the properties of RSS data in the frequency domain with the technique of DFT and shows that the first few Fourier coefficients can be extracted as characteristics of a RSS sequence. According to the Parseval theorem, we present an indoor localization method based on the Euclidean distance of two signal samples using their characteristics in the frequency domain. Experimental results illustrate that with short time signal samples from only three access points, a few coefficients are adequate to provide good locating performance.