The Contribution of Distributed Scattering in Radio Channels to Channel Capacity: Estimation and Modeling

A widely used radio channel model approximates the radio channel impulse response by a superposition of a finite number of propagation paths. Using the concentrated propagation paths model only, 30-100% of the variance in the measurement data can be explained, depending on the scenario. Therefore, it has been proposed to extend the data model by an additional component describing the distributed scattering of the radio channel. The model for the DMC is parameterized by three parameters, a base delay, the coherence bandwidth or delay-spread, and the attenuation factor of the dense multipath component. It is shown in this paper that the distributed scattering contributes significantly to the capacity of the MIMO-wideband radio channel. In fact it can be observed in channel sounding measurements that the distributed scattering can contribute more to the channel capacity than the concentrated propagation paths, depending on the scenario.