Comparison of a logarithmic and a linear indoor lift car propagation model

In indoor cellular coverage planning, the lift shaft and the associated lift car create one of the most difficult propagation environments. In this paper the radiowave propagation in such an environment was studied and new empirical propagation models were introduced. The new models were adjusted by using multiple linear regression to the results of the measurements performed at 900 MHz and at 1800 MHz. The calculated RMS error for the new logarithmic empty lift car model was 2.15 dB and for its extension with persons in the lift car it was 2.02 dB. The results for the corresponding new linear models were 2.94 dB and 2.56 dB. These results combined with the new information of the lift car attenuation are valuable progressions concerning indoor radio network planning and radiowave propagation knowledge in a lift car.