A Diagnosis Method for Radio Frequency Channels of Wireless Devices Without Cable Connections

The diagnosis of radio frequency (RF) channels (chains) is crucial in the mass production stage of wireless devices. However, the conventional conducted testing for the RF channel diagnosis is inconvenient for devices with integrated antennas. This work presents a cost-effective and time-efficient over-the-air (OTA) diagnostic approach for performance evaluations of the RF channels in a nondisruptive manner, applicable for wireless devices in time division duplex (TDD) mode. A new unidirectional search method is put forward to reduce the measurement uncertainty. The maximum absolute deviation between the proposed method and conducted testing was only 0.3 dB. Small measurement uncertainties of the whole testing system for the RF output power test and sensitivity test confirm the effectiveness of the proposed methodology.