A stochastic radio channel model (SRCM) for broadband indoor mobile systems operating at 5.2 and 17 GHz has been derived within the ACTS project AC085 Magic WAND. The SRCM accurately describes the dispersive nature of real radio channels in time, frequency, direction, and polarization. These effects are important for the design and performance evaluation of advanced receiver structures that exploit the inherent channel diversity, e.g., by means of adaptive antennas. The wideband SRCM takes into account all relevant propagation effects observed in real indoor environments. For example, it includes large-scale fluctuations such as transitions where waves are emerging and vanishing as well as the delay drift of the waves. In the paper, the modeling approach adopted for the SRCM is described and illustrated by simulation results. I Introduction A profound knowledge of the radio channel characteristics is a prerequisite for the development of efficient wireless transmission systems. Many ..