Marin Stoytchev

Communication in a disordered world

Rather than decreasing efficiency, scattering can actually increase the information transfer rate for cell phones and other wireless microwave communication devices. Mesoscopic physics helps explain how.

Statistics of the MIMO radio channel in indoor environments

This paper presents a statistical study of the multiple-input multiple-output (MIMO) radio channel in indoor environments in relation to the capacity of multi-antenna wireless systems. Indoor measurements of the transmission matrix, H, at 2.45 GHz are performed using a 16/spl times/16 multi-antenna system in the case of line-of-sight (LOS) and in the case when it is completely obstructed (off-axis). This allows us to study the statistics of the capacity of systems with a large number of antennas N for both Rician and Rayleigh fading channels. In addition, we examine the statistics of the eigenvalues of the transmission matrix, which provide subtle details about the MIMO channel in the case of LOS and off-axis that could be of significant importance for practical applications. Relevant theoretical simulations are performed, which show good agreement with the results obtained from measurements.

Beyond 3G: Metamaterials application to the air interface

We have presented the first metamaterial MIMO antenna array implemented in a commercially available 802.1 In wireless LAN access point. Despite the extremely small size of the metamaterial array, its performance equals that of the much larger conventional antenna solution. The metamaterial antenna array utilized existing PCB fabrication technology and was readily integrated into the access point.