Wi-Fi Based Indoor Positioning System Using Hybrid Algorithm

하이브리드 알고리즘을 이용한 Wi-Fi 기반의 실내 측위 시스템

Shin, Geon-Sik;Shin, Yong-Hyeon

  • Received : 2015.11.20
  • Accepted : 2015.12.22
  • Published : 2015.12.30


GPS is the representative positioning technology for providing the location information. This technique has the disadvantage that does not operate in the shadow areas, such as urban or dense forest and the interior. This paper proposes a hybrid indoor positioning algorithm, which estimates a more accurate location of the terminal using strength of the Wi-Fi signal from the indoor AP. To determine the location of the user, we establish the most appropriate path loss model for the measurement environment. by using the RSSI value measured in a variety of environment such as building structure, person, distance, etc. The path loss exponent obtained by the path loss model is changed according to the environment. REKF, PF estimate the position of the terminal by using measured value from the AP with path loss exponent. For more accurate position estimation, we select positioning system by the value of threshold measured by experiments rather than a single positioning system. Experimental results using the proposed hybrid algorithm show that the performance is improved by about 17% than the conventional single positioning method.


GPS;Hybrid;Indoor positioning system;Kalman filter;Particle filter


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Supported by : 서울과학기술대학교