Integrated sensing and communication based on space-time-coding metasurfaces(www.nature.com)
39 pointsby westurner5 days ago3 comments
  • mikewarot5 hours ago
    This seems like a wild work around to retrofit a non-MIMO system into the modern era with beamforming chips a-plenty. While it's interesting to consider using an AI to detect and steer the beam using the harmonics of the received signal, it's important to bear in mind these will be about 20 dB down from the fundamental received frequency.

    It would be far more reliable to employ a phased array transceiver which can do multiple concurrent beamforming operations. This would allow the use of the antenna for multiple connections on the fundamental frequency.

    If it's truly for a single channel/single user, it would be simpler to simply time-multiplex a search for reflections by random sampling, or perhaps even gradient descent.

  • westurner5 days ago
    ScholarlyArticle: "Integrated sensing and communication based on space-time-coding metasurfaces" (2025) https://www.nature.com/articles/s41467-025-57137-6

    NewsArticle: "Space-time-coding metasurface could transform wireless networks with dual-functionality for 6G era" https://techxplore.com/news/2025-03-space-coding-metasurface...

  • cr125ridera day ago
    So this is a sort of wireless amplifier?
    • RossBencinaa day ago
      I think it's more like an active antennae/analog signal processing structure that can tightly control spatial radiation properties (direction, amplitude, phase). Think beamforming, but with a continuous micro-structured surface rather than discrete antennae. In this case, the "antennae" is not only a planar object with sub-wavelength microstructure, but may also include circuit elements that can dynamically alter the surface properties. At least that's what I got from skimming the first three paragraphs. Sounds very interesting.
      • exe34a day ago
        I love this sort of thing, it reminds me of Neal Asher's polity enemies who often have devices being grown on their surface where powerful laser beams or other weapons emerge.