Urban indoor signal level characterization in the Medium Wave band

This paper presents an analysis of urban indoor signal strength reception in the Medium Wave band. Measurements were carried out in the cities of Bilbao and Vitoria (Spain) at six frequencies: 639 kHz, 990 kHz and 1305 kHz for Bilbao, and 612 kHz, 1197 kHz and 1602 kHz for Vitoria. Results show that mean building penetration losses depend on reference streets´ width and environment type, and that generally decrease with frequency and with floor level, although generally losses in first floor are higher than losses in main floor. Averaging values of locations in first three enclosed floors of every building at once, building penetration losses decrease from 6 dB to 1 dB from 612 kHz to 1602 kHz, using a logarithmic approximation. High spatial standard deviations are obtained for building penetration losses in every case so values have been refined grouping buildings as a function of the street´s width at the illuminated façade and the environment type, differentiating a very dense urban environment with generally narrow streets like Bilbao from Vitoria, where there are generally wider streets and less density of buildings. High values in standard deviation remain but lower than averaging every building at once.