Random Time-Space Coding Metasurfaces for Spatial Control of the Temporal Statistics of Electromagnetic Fields

Area of Science:

• Metasurface technology
• Electromagnetic field control
• Statistical physics

Background:

• Conventional digital coding metasurfaces generate deterministic electromagnetic (EM) responses.
• Controlling random EM fields requires achieving target temporal statistical properties.
• Existing methods lack control over spatial distributions of statistical properties like mean and variance.

Purpose of the Study:

• To propose a novel framework for controlling the spatial distribution of temporal statistical properties of EM fields.
• To utilize random time-space coding metasurfaces (RTCM) for probabilistic EM field structuring.
• To enable simultaneous direct transmission and jamming capabilities.

Main Methods:

• Development of a statistical model for RTCM within a probability space.
• Establishing the relationship between random code distributions (marginal and pairwise joint) and EM field statistics (mean and variance).
• Generating time-varying random EM fields using sampling codes constrained by target statistical distributions.

Main Results:

• Demonstrated that spatial mean and variance distributions of EM fields are governed by the statistical properties of the random codes.
• Successfully generated time-varying random EM fields with desired spatial mean and variance distributions.
• Showcased the capability for simultaneous direct transmission and jamming through spatial mean and variance peaks.

Conclusions:

• The proposed framework extends metasurface applications into the probability domain, shifting from deterministic to probabilistic control.
• This research opens new avenues for communication systems, information security, and electromagnetic countermeasures.
• RTCM offers a powerful new paradigm for advanced EM field manipulation.