A hidden environment model for constructing indoor radio maps

Constructing indoor radio maps plays an important role in many services and applications, such as wireless base station planning. We propose a hybrid approach to constructing indoor radio maps by developing a novel indoor signal propagation model, called the hidden environment model (HEM). The model is hybrid because it combines on-site measurements with a number of different types of calculations. As part of this model, we introduce the idea of an environment factor matrix (EFM). The EFM represents a model of the environmental features that affect radio attenuation. We also develop a lazy sampling algorithm to help generate the EFM. The goal of the lazy sampling algorithm is to balance the number of measurements that need to be taken with our model´s accuracy. The goal is to minimize the measurement workload while maintaining satisfactory accuracy. We evaluate our model by comparing the radio maps calculated from the model to a radio map obtained by exhaustive measurements. The results show that our hidden environment model achieves good accuracy.