MIMO over-the-air (OTA) measurements and simulations for network and terminal performance evaluation and prediction are receiving strong interest due to the urgent need to develop test standards for 4G systems. The inclusion of MIMO in LTE terminals is extremely important, yet testing MIMO performance “OTA” has proven to be particularly complex compared to SISO OTA, and developing a test standard is taking considerable time. Unlike SISO OTA which was relatively straightforward, MIMO OTA is highly dependent on the characteristics of the radio channel, and, as such, many different test methods have been proposed which vary widely in their radio characteristics, size, and costs. Major challenges remain in the areas of identifying the optimal channel models and test methods. Particular attention is needed around test system accuracy which has to be bounded in order that a method can differentiate between good and bad MIMO performance. Therefore, we invite investigators to contribute original research articles as well as review articles that will stimulate the continuing efforts to understand MIMO OTA and facilitate the development of industry-wide international test standards. We are particularly interested in articles describing accurate evaluation methods and models, measurement outcomes from advanced test trials, and advances in terminal performance predictions. Potential topics include, but are not limited to:

• The development of strategies to create cost-effective test solutions
• The emulation of complex power delay profiles (PDPs), including dense multipath components (DMCs), polarization and directional properties of the channel using mode-stirred reverberation chambers (MSRCs)
• Hardware efficient emulation of the 3D wave field, polarization properties, and uniform PDP in anechoic chambers (ACs)
• The degree of uncertainty when using ACs and/or MSRCs
• Significant measures for a fair comparison of terminals when using MIMO OTA techniques
• Results of MIMO OTA tests of LTE prototypes
• Role of passive MIMO antenna performance
• Variable reference channel emulation mechanisms using different test scenarios and their combinations thereof

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