Novel Applications of MIMO Antenna System for Active Suppression of Electromagnetic Fields

Active suppression of noise and vibrations is a well established field of research with many applications in acoustic and mechanical industries. In this report we test some of these active control methods combined with MIMO antenna system in order to assess their validity and performance when applied to electromagnetic fields. The application that we evaluated is a model of a mobile phone equipped with one ordinary transmitting antenna and a number of actuator-antennas which purpose is to cancel out the electromagnetic field at a specific volume in space (e.g. at the human head) while maintaining a predefined level of the overall output power of the system. This power control is achieved through the use of a quadratic constraint on the active control algorithm. In addition, we will also investigate the impact of MIMO antenna parameters and carrier frequency on the performance of the system. Simulation results show the promise of using the adaptive control algorithms and MIMO system to attenuate the electromagnetic field power density