Long Term Evolution (LTE) requires Multiple Input Multiple Output (MIMO) antenna systems. Consequently a new over-the-air (OTA) test methodology need to be created to make proper assessment of LTE devices radiated performance. The antenna specific parameters i.e. total antenna efficiency, gain imbalance and correlation coefficient, are essential for a proper MIMO antenna system design. However it can't be use directly to assess the LTE device system performance, since a multiplicity of other factors are involved, e.g. power amplifier load- pull, low noise amplifier source-pull, self interference noise, baseband algorithm and other factors. Several standard organizations are working towards a consensus over the proper OTA MIMO test method, however so far results of measurement campaigns have ambiguous results not allowing a desirable progress . Initially presented at one of several MIMO OTA standard meetings , the reference antenna was conceived considering the special case of uniform distribution of incoming power. This paper shows an antenna system that will aid standard organizations and research labs adopting anechoic or reverberation chambers to proper investigate OTA radiated performance, ruling out the LTE devices unknown MIMO 2x2 antenna performance.
Ieee Vehicular Technology Conference, 2012, p. 1-5