A 77-GHz Six-Port Sensor for Accurate Near-Field Displacement and Doppler Measurements

Area of Science:

• * Millimeter-wave integrated circuits
• * Radio frequency (RF) sensing technology
• * Interferometry

Background:

• * Continuous-wave (CW) radar sensors are crucial for various applications.
• * Six-port interferometer technology offers a cost-effective and accurate sensing solution.
• * Existing designs require further optimization for performance and integration.

Purpose of the Study:

• * To propose and validate a novel continuous-wave (CW) radar sensor design.
• * To demonstrate the feasibility of a millimetre-wave six-port interferometer for sensing.
• * To achieve high accuracy in distance and Doppler frequency measurements at a reasonable cost.

Main Methods:

• * Design and fabrication of a millimetre-wave six-port interferometer sensor prototype at 77 GHz.
• * Integration of transmitter, receiver antenna, six-port interferometer, and power detectors on a single die.
• * Experimental assessment using calibrated tuning forks for performance evaluation.

Main Results:

• * Successful fabrication and measurement of a complete sensor prototype.
• * Demonstrated high accuracy in distance and Doppler frequency measurements.
• * Achieved accurate phase measurements, highlighting the potential of six-port technology.

Conclusions:

• * The proposed six-port interferometer sensor is a promising candidate for CW radar sensing.
• * Advances in six-port technology offer improved performance, compactness, and robustness.
• * This technology is expected to significantly contribute to human tracking and industrial sensors.