Performance of different theoretical small antennas in isotropic 3-D and horizontal 2-D multipath environments with application to OTA testing

TLDR: In this paper, a comparison of theoretical results of simulating such tests in rich isotropic 3D and horizontal 2D environments is presented in terms of Mean Effective Gains (MEG) or rather Mean Effective Directivities (MED) and apparent diversity gains.

Abstract: There is a need for new measurement methods that can emulate multipath environments for Over-The-Air (OTA) testing of devices with small antennas and in particular when the communication system can generate dynamically changing multiple channels through the multipath by means of multiport antennas, i.e. having MIMO capability (Multiple Input Multiple Output). The reverberation chamber has during the last ten years been developed into an accurate method for such testing [1], representing an isotropic three-dimensional (3-D) environment with a uniform distribution of incoming waves over the unit sphere. Lately it has been proposed to instead perform such tests in a horizontal two-dimensional (2-D) environment realized by antennas located in a ring around the DUT. This paper will present a comparison of theoretical results of simulating such tests in rich isotropic 3-D and horizontal 2-D environments. The results are presented in terms of Mean Effective Gains (MEG) [2] or rather Mean Effective Directivities (MED) [1], and apparent diversity gains [3], obtained by using a multipath simulator based on the receive antenna equivalent circuit in [4] and the theory in [5].