A Polarization‐Modulated Information Metasurface for Encryption Wireless Communications

Abstract

Programmable and information metasurfaces have shown great potentials in wireless communications, but there are few reports on encrypted communications. In this paper, a programmable polarization-modulated (PoM) information metasurface is proposed, which can not only customize arbitrarily linearly polarized reflected waves, but also modulate their amplitudes in real time. Based on this feature, a physical-level wireless communication encryption scheme is presented and experimentally demonstrated by introducing a meta-key, which can be encrypted and sent by the programmable PoM information metasurface. To be specific, the key is encoded and concealed into different linear polarization channels, and then modulated and transmitted by the information metasurface at the transmitting end. At the receiving end, the modulated signal can be received and decoded by using a pair of polarization discrimination antennas. A wireless transceiver system is established to verify the feasibility of the scheme. It is shown that, once the meta-key is obtained, the corresponding encrypted target information that has been sent to the user in advance can be recovered.

Non‐Interleaved Four‐Channel Metasurfaces for Simultaneous Printing and Holographic Imaging

“…Metasurfaces, which are composed of 2D subwavelength artificial structures, possess powerful ability in manipulating the amplitude, phase, polarization, and spectrum of electromagnetic (EM) waves from microwave, terahertz to visible light, which have attracted widespread interest in both scientific community and engineering fields. [1][2][3][4][5][6][7][8][9][10][11][12][13][14] Due to their capacity of tailoring EM waves pixel by pixel, metasurfaces have also been extensively employed in the holographic imaging based on phase modulation, which overcomes the shortcomings (such as bulky frame and low efficiency) of conventional holographic displaying techniques. [15,16] Metasurfaces with both amplitude and phase controls provide more powerful ability to modulate the wave fronts, [17][18][19][20][21][22][23] which can recover holographic images with higher fidelity and sharpness.…”

A review of light‐controlled programmable metasurfaces for remote microwave control and hybrid signal processing

“…[67][68][69][70][71] More importantly, because of real-time switching capability, programmable metasurface can realize information processing while manipulating EM fields and waves, giving rise to a new concept of information metasurface. [72][73][74][75][76][77] Information metasurface bridges the physical world and digital world, which provides an efficient platform for controlling wave-information-matter interactions, thus enabling many attractive devices and systems, such as simplified-architecture transmitter, 64,77 real-time imager, 49,78 programmable radar, 75 and so on. [79][80][81][82][83] Electrical control is a popular way to achieve programmable metasurfaces.…”

“…By combining with sensors and artificial intelligence, programmable metasurface can be extended to develop intelligent metasurface with self‐adaptive ability 67‐71 . More importantly, because of real‐time switching capability, programmable metasurface can realize information processing while manipulating EM fields and waves, giving rise to a new concept of information metasurface 72‐77 . Information metasurface bridges the physical world and digital world, which provides an efficient platform for controlling wave‐information‐matter interactions, thus enabling many attractive devices and systems, such as simplified‐architecture transmitter, 64,77 real‐time imager, 49,78 programmable radar, 75 and so on 79‐83 …”

Full Spectral Image Encryption in the Infrared using an Electrically Reconfigurable Metasurface and a Matched Detector

“…To this end, several works have proposed metasurfaces for encoding image-based information on multiple wavelength and polarization channels. [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28] In the visible wavelength range, metasurfaces have been designed to generate holograms [26,29] and to serve as pixelated color displays [30,31] for encoding images. In the infrared (IR), metamaterials with thermally [20,32] and electrically [33] reconfigurable spatial emissivities have been investigated for information encoding.…”