Reconfigurable MIMO: Design and performance analysis

Reconfigurable multiple antenna systems (MR-MIMO) are MIMO systems that consist of smart antenna elements whose radiation pattern, frequency band and polarization properties can be changed. With an MR-MIMO antenna system, both element factor, F(φ, θ), and array factor, A(φ, θ)) of the antenna can be modified to achieve a desired antenna radiation pattern F(φ, θ) × A(φ, θ). In this paper, we investigate a pixelantenna based MR-MIMO system that can create a finite number of different antenna radiation patterns, and design transmit and receive algorithms that can perform precoding and antenna mode selection at the same time. Since each mode of an MR-MIMO antenna may result in a different matrix channel realization, we also study channel estimation methods and look into to the impact of channel estimation overhead on the performance gains of MR-MIMO system. Methods that can jointly design antenna mod selection and precoder matrix is also introduced and their performance is analyzed via simulations. Results indicate that significant SNR gains can be achieved with MR-MIMO antennas compared to the traditional MIMO antennas.