Over-the-Air Testing for Carrier Aggregation Enabled MIMO Terminals Using Radiated Two-Stage Method

Multiple-input multiple-output (MIMO) over-the-air (OTA) testing of wireless devices has become increasingly attractive in radiated performance evaluation. As one of the OTA testing methods, the radiated two-stage (RTS) method achieves flexible channel models with low-system cost. However, the existing MIMO OTA testing using RTS method is valid only for single carrier frequency application. This paper applies the RTS method to multiple carrier frequency applications [carrier aggregation (CA)]. Two setups are presented to discuss system cost and calibration time. To validate the RTS OTA testing for CA, the transfer matrices from the OTA antenna ports to device under test antenna ports in three types of RF shielded enclosure are investigated. The results demonstrate that the applied RTS method for CA works better in anechoic chambers. One calibration matrix might need to be adopted for each component carrier when the frequency separation of component carriers is large.