Spatially-resolved near-field diagnosis of differential signaling performance for wireless device RFI/EMC applications

摘要

This paper presents a method to spatially diagnose amplitude and phase imbalances of high-frequency/high-speed differential signaling on a wireless device with a high resolution near-field scanning system. The principle of measuring the complex-valued magnetic near fields with vector network analyzer (VNA) is discussed. Then the measured complex-valued magnetic near fields over several differential circuits are used to study the radio-frequency interference (RFI) and electromagnetic compatibility (EMC) issues related to these circuits in a wireless device that is under a working state.