MIMO 2×2 reference antennas concept

Long Term Evolution (LTE) adopt multi-antenna mechanisms to increase coverage and physical layer capacity, therefore Multiple Impute Multiple Output (MIMO) antenna systems are required on LTE systems. Besides the antenna system figure of merit (FoM), i.e. absolute system gain, gain imbalance, correlation coefficient the MIMO system performance is defined by radiated data throughput. Different standard bodies are working towards test methodologies to proper emulate the radio propagation environment therefore determining MIMO performance. This task had become very complex based on several implementation details pertinent of each test methodology. This paper will introduce the concept of MIMO 2×2 reference antenna for the special case of uniform incoming power distribution. Hereby part of measurement uncertainty is eliminated through the adoption of a set of MIMO 2×2 antennas with known FoM, and controllable performance.