Due to its cost and power performance, Zigbee is widely used and can be applied to railway systems. This paper deals with the performance of a Zigbee (IEEE.802.15.4) RF signal, according to several criteria; this analysis is based on an experimental approach and specially on power measurements in an anechoic chamber taken into account reflection on metal wall effects on wave propagation. As a first step, the experiments are realized on a laboratory reduced scale railways system which is also described in the paper. The signal strength is measured at several distances and analyzed according to the modulation and the polarization of antennas. Then, Zigbee modules are integrated into the wagons of the laboratory platform. The impact of the metallic walls of the wagons is analyzed and evaluated by an experimental approach and validated with a theoretical model This analysis can then be used as a first approach to optimize communication between ZigBee modules put into two wagons with metallic walls. © 2015 IEEE.