Dynamically reconfigurable holographic metasurface aperture for a Mills-Cross monochromatic microwave camera

• Published in: Optics express Vol. 26; no. 5; pp. 5281 - 5291
• Main Authors: Yurduseven, Okan, Marks, Daniel L, Fromenteze, Thomas, Smith, David R
• Format: Journal Article
• Language: English
• Published: United States Optical Society of America - OSA Publishing 05.03.2018
• Subjects: Electromagnetism; Engineering Sciences; Signal and Image processing
• ISSN: 1094-4087; 1094-4087
• DOI: 10.1364/OE.26.005281

We present a reconfigurable, dynamic beam steering holographic metasurface aperture to synthesize a microwave camera at K-band frequencies. The aperture consists of a 1D printed microstrip transmission line with the front surface patterned into an array of slot-shaped subwavelength metamaterial elements (or meta-elements) dynamically tuned between "ON" and "OFF" states using PIN diodes. The proposed aperture synthesizes a desired radiation pattern by converting the waveguide-mode to a free space radiation by means of a binary modulation scheme. This is achieved in a holographic manner; by interacting the waveguide-mode (reference-wave) with the metasurface layer (hologram layer). It is shown by means of full-wave simulations that using the developed metasurface aperture, the radiated wavefronts can be engineered in an all-electronic manner without the need for complex phase-shifting circuits or mechanical scanning apparatus. Using the dynamic beam steering capability of the developed antenna, we synthesize a Mills-Cross composite aperture, forming a single-frequency all-electronic microwave camera.