Human-Body Shadowing Modeling for Indoor Quasi-static MIMO Channels

In recent years, MIMO communication systems such as IMT-Advanced and LTE have been put into practical use. Since MIMO transmission has an advantage in use in the indoor multipath-rich environment, the accurate indoor MIMO channel model is necessary for evaluating the systems. In indoor Quasi-static environment, it is known that the channel state changes dynamically due to the human-body shadowing effect even if the receiver and the transmitter are fixed. We have proposed the estimation method of human-body shadowing of each cluster for MIMO channel modeling. In our proposal, firstly the propagation parameter distributions of clusters are estimated from the data measured in static condition using SAGE and K-Power-Means algorithm. Next, the human-body shadowing of each cluster is estimated from the Beamformer resultant power variations of cluster that are calculated from the data measured in quasi-static condition. We carried out the 3.35GHz measurements in the cafeteria during lunch time. As a result, we showed that shadowing level was from 5dB to 15dB at busy time of cafeteria. In addition, we also showed that the mean decrease and variance of resultant power is almost in the proportional relation.