No abstract

No abstract

Abstract-The beamspace domain of parasitic antenna arrays is explored in this paper, providing the aerial degrees of freedom available for use in Multiple Input-Multiple Output (MIMO) systems. The beamspace representation allows for the design of an alternative MIMO architecture based on single radio-frequency (RF) chains, and facilitates the inclusion of MIMO transceivers in devices with strict size limitations. A three dimensional orthogonal expansion is performed on the beamspace domain providing the basis patterns used for mapping of the transmitted symbols and for sampling at the receiver. The expansion is based on the Gram-Schmidt orthonormalization procedure and can be generalized for any parasitic antenna array. The multiplexing capability of ESPAR antennas is presented as a means for supporting future performance demanding communication systems. Performance evaluation results are illustrated in detail.

No abstract

Significant research effort has been drawn over the last few years to reduce the hardware complexity and size of Multiple Input -Multiple Output (MIMO) systems and to push this promising technology even to lightweight and small portable devices. Among other architectures, single-fed MIMO systems with compact parasitic arrays are a possible candidate toward this goal. To facilitate the study and design of parasitic arrays for MIMO applications, this paper presents an alternative signal model considering the currents at the ports of the transmitting array as the input to the system. Based on this model, a novel parasitic array is designed that is able to multiplex 16-QAM signals with the aid of a single radio-frequency (RF) source. The proposed signal model can also be useful for the evaluation of large parasitic arrays in massive MIMO regime, with significantly reduce hardware burden.