3D Reflectometer Design for Embedded RF Vector Measurement

A novel 3D 4-port non-directional reflectometer for measuring complex reflection coefficients is proposed. The proposed reflectometer features two optimized non-directional sniffers positioned below a transmission line with buried lines to carry the sniffed signals to power detectors in LTCC technology. Vertical transitions from the buried lines to surface microstrip lines are designed and optimized. 3D electromagnetic field simulations are used to optimize the proposed design. A prototype of the proposed reflectometer is fabricated and used to measure 45 different complex loads. The obtained results show excellent agreement with VNA measurements showing errors below 0.3 dB for amplitude and below 3° for phase.