Influence Analysis of Charging on mm-Wave OTA Testing

OTA testing becomes mandatory for performance evaluation of wireless devices in 5G era, especially for millimeter wave (mm -Wave) use cases, which causes a dramatic increase in overall test time comparing with that of Sub- 6 GHz ones. Accordingly, due to its battery depletion, it is impossible to complete the entire OTA testing of the DUT without recharging, cooling, and repositioning, which could further extend the test duration to an unacceptable level. To solve this problem, enabling an external charging cable during the mm-Wave OTA testing is a potential solution, which however has not been approved in industry yet. This paper evaluates the potential impact of the external charging cable on measured OTA Tx performance of the mm-Wave DUTs across different operation bands. Based on the comparison campaign, it can be found that the measured performance variation over different UEs as well as frequency bands could be considered very small, which therefore suggests that the external charging cable should be permitted in 5 G mm-Wave OTA testing.