Optimum Weight Parameter of Weight Centroid Method for Indoor Positioning in Environment with Different Path Loss Exponent and Multipath Fading Effect

Abstract

This paper proposes optimum weight parameter of weight centroid method for indoor positioning in environment with different path loss exponent and multipath fading effect. The indoor environment is defined as square with each side 10 m long. There is a transmitter installed in the center of each side. The distance error model is applied to calculate the distances between the location coordinates of user and the location coordinates of transmitters in environment with different path loss exponent and multipath fading. The total 100 location coordinates of user are estimated by using weight centroid method, varying weight parameter in the range of 1 to 10. The optimum weight parameter is defined as the case where mean of distance error of all positions is the least. The optimum weight parameter for environment with different path loss exponent and multipath fading effect is illustrated. The results show that the optimum weight parameter changes slightly with the path loss exponent and tends to change with the standard deviation of the multipath fading effect divided into 3 periods. The first period tends to increase slowly, the second period tends to increase rapidly, and the third period tends to fluctuate up and down. Moreover, the size of the indoor environment has very little impact on the optimum weight parameter. These results make it possible to select optimum weight parameter for case with path loss exponent and standard deviation of multipath fading effect that match or are close to the channel of indoor environment.