Active Sensor for Microwave Tissue Imaging with Bias-Switched Arrays

Area of Science:

• Microwave Engineering
• Biomedical Imaging
• Sensor Technology

Background:

• Advancements in active arrays are crucial for next-generation microwave tissue imaging.
• Miniaturization of sensor components is essential for achieving high-density arrays.
• Controlling sensor states is key to optimizing performance and dynamic range.

Purpose of the Study:

• To develop and characterize a prototype bias-switched active sensor for microwave tissue imaging.
• To establish the achievable dynamic range of the sensor for improved imaging.
• To assess the sensor's suitability for dense active array configurations.

Main Methods:

• Integration of a printed slot antenna, low-noise amplifier (LNA), and active mixer into a single compact unit.
• Implementation of a bias-switching circuit to simultaneously control the LNA and mixer.
• Experimental measurement of the sensor's dynamic range across different resolution bandwidths.

Main Results:

• The developed sensor is compact, allowing for inter-sensor distances as small as 12 mm.
• The sensor operates over a bandwidth of 3 GHz to 7.5 GHz with a 30 MHz intermediate frequency (IF).
• Experimental results show a dynamic range of 109 dB at 1 kHz and 118 dB at 100 Hz resolution bandwidth.

Conclusions:

• The prototype bias-switched active sensor demonstrates significant potential for microwave tissue imaging arrays.
• The sensor's design enables high dynamic range performance crucial for detailed imaging.
• The compact size and performance characteristics support the development of advanced, high-resolution microwave imaging systems.