Reconfigurable antennas and distributed bit loading for MIMO ad-hoc networks

In this work we evaluate the performance impact of reconfigurable antennas in a Multiple-Input Multiple-Output ad-hoc network where the links are allowed to transmit at the same time and interfere with each other. To achieve this goal, we have used two Reconfigurable Circular Patch Antennas (RCPA) to take channel measurements in a 3-link topology. To quantify the performance, instead of using Shannon capacity, we restrict the links to use an integer number of bits per transmission, with constraints on an application-imposed BER, as well as total available power per link. As the focus of this paper is on ad-hoc networks, we present iterative algorithms that achieve antenna configuration selection as well as bit and power loading in a distributed manner. By using an integer number of bits as well as SINR-based BER constraints, we aim to provide a realistic evaluation of the performance impact of reconfigurable antennas in a MIMO ad-hoc network.