2.4GHz ISM band radio frequency signal indoor propagation

Indoor environment is from the point of the wireless communication an extremely hostile environment. Despite this fact, wireless sensor network applications in the indoor environment are very common. Having signal propagation in a real environment, without considering interferences from other sources, we meet (not only indoors) four basic phenomenons - path-loss, reflection, diffraction and scattering. Each of these effects impact on the spread of the signal and contributes to attenuation and distortion at the receiver side. Detailed description of the electromagnetic wave propagation can theoretically obtain the solution of Maxwell´s equations. However, this is too demanding and for practical cases unusable. In practice, to describe the signal propagation, the approximate models are used, which are often based on experimental results. This contribution includes case study on indoor radio frequency signal propagation at 2.4GHz ISM Band with related math, supported by implementation of the propagation models and experimental results.