A Review of Microstrip Patch Antenna-Based Passive Sensors

Area of Science:

• Electromagnetics and Applied Physics
• Sensor Technology

Background:

• Antennas are crucial for passive sensing, with their operating principles and structural designs dictating performance.
• Understanding material electrical properties (conductivity, loss tangent, resistivity) is key to antenna-based sensing mechanisms.

Purpose of the Study:

• To provide a comprehensive overview of existing antenna-based passive sensing techniques.
• To discuss the fundamental sensing mechanisms, key parameters, and factors affecting sensing performance.
• To explore advancements in millimeter-wave and resonator antenna sensors.

Main Methods:

• Review of antenna operating principles and structural designs.
• Analysis of material electrical properties' effects on sensing.
• Discussion of key parameters like operating frequency and impedance.
• Examination of reflected wave characteristic alterations for sensing.

Main Results:

• Passive sensing via antennas is achieved by modifying reflected wave characteristics (frequency, return loss, phase, signal strength).
• Material properties significantly impact antenna sensing capabilities.
• Millimeter-wave and resonator sensors show increasing relevance and advancements.

Conclusions:

• Antenna-based passive sensing offers diverse techniques with varying advantages and drawbacks.
• Further improvements in passive antenna sensing performance are achievable through optimized designs and material selection.
• Addressing current challenges and exploring future directions are essential for advancing the field.