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  • If I understand correctly, is the application of this to quickly switch the direction of sending/receiving? Are there any other applications?
    by d4ng
  • How difficult it is to get a perfect beam in practice? Can one manufacture a flat rotman lense like that to introduce sinc phase shifts - this should yield a well behaved very directed beam? What are the practical challenges in doing so?
    by bbminner
  • Rotmans are elegant, but these days you can get full-duplex all digital phased arrays for cheap: https://www.crowdsupply.com/scale-rf/quadrf#
    by go_artemis
  • Hey if anyone else is wondering what the heck this thing actually does, there's a beautiful visualization made by Lukas Henkel on his LinkedIn: https://www.linkedin.com/posts/lukas-henkel-ovt_simulation-e...
    by summarybot
  • Suppose this is connected to a multiple-output RF transmitter (amplifier), what are the advantages/applications of shifting the phases of the signals passively with a Rotman Lens versus shifting the phases of the signals prior to feeding them to the transmitter (i.e. in the generator)? is the main purpose to compensate for different antennae geometry without having to change the signal generator? I guess things are very different when you can't commute everything into your SDR algorithms.
    by RossBencina
  • I wonder if you could do this with sea walls and gates and make beamformeable surf breaks.
    by totetsu
  • You can do something similar in 3D with Luneberg lenses, as used on the AN/SPG-59[1]. A truly wild piece of engineering, as is the following SCANFAR system if you're into that sort of thing. I can only assume someone in the top brass had a skim of Arthur C Clarke's Superiority and forwarded it straight on to engineering with a big green approved stamp.

    1. https://secwww.jhuapl.edu/techdigest/content/techdigest/pdf/...

    by Skwid
  • R.F Turner is a pretty nice example of nominative determinism. Parents up and named him "radio frequency dial", so of course he works in antenna technology
    by amarant

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