An optimization model for the indoor access point placement problem with different types of obstacles

Choosing the ideal spot to set up an Access Point (AP) in a given plant is no simple task. This paper proposes a mathematical model and computational solution to the following problem: given the plant of an indoor environment, a number of reception points and properly characterized obstacles, locate where the access point should be installed, so as to minimize the propagation losses within the environment and ensure a minimum signal level in all receivers. The model proposed differs from others in the literature by treating each obstacle individually and taking into account the material from which it is made. The proposed design minimizes the sum of the attenuations of the signal generated by the AP as the signal traverses the fewest possible obstacles whose attenuation is large (e.g., concrete walls and metal cabinets). To validate the proposed model simulations were performed in an indoor environment with a certain distribution of obstacles of different kinds. The experiments show that the location of the access point varies significantly in the environment according to the materials composing the obstacles. In the most critical case, with obstacles made of concrete, the optimization algorithm could find no location for the AP so that all receptors received a minimum signal level to establish a connection.