Portable Real-Time Microwave Camera at 24 GHz


This paper presents a microwave camera built upon a two-dimensional array of switchable slot antennas. The camera borrows from modulated scattering techniques to improve isolation among the array elements. The camera was designed to measure vector electric field distribution, be compact, portable, battery operated, possess high dynamic range, and be capable of producing real-time images at video frame-rate. This imaging system utilizes PIN diode-loaded resonant elliptical slot antennas as its array elements integrated in a simple and relatively low-loss waveguide network thus reducing the complexity, cost and size of the array. The sensitivity and dynamic range of this system is improved by utilizing a custom-designed heterodyne receiver and matched filter for demodulation. The performance of the multiplexing scheme, noise-floor and dynamic range of the receivers are presented as well. Sources of errors such as mutual-coupling and array response dispersion are also investigated. Finally, utilizing this imaging system for various applications such as 2-D electric field mapping, and nondestructive testing is demonstrated.


Electrical and Computer Engineering

Keywords and Phrases

Electric Field Mapping; Microwave Camera; Nondestructive Testing; Real-Time Imaging; Switchable Slot Antenna; 2-D Electric Field; Array Elements; Array Response; Dynamic Range; Electric Field Distributions; Frame-Rate; Heterodyne Receivers; High Dynamic Range; Low-Loss Waveguides; Modulated Scattering Techniques; Multiplexing Schemes; Two-Dimensional Arrays; Antenna Arrays; Semiconductor Diodes

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Document Type

Article - Journal

Document Version


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© 2012 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

01 Feb 2012