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Cell Towers Can Double as Cheap Radar Systems for Ports and Harbors (2014)

(spectrum.ieee.org)
137 points transpute | 2 comments | 29 Jun 25 21:48 UTC | HN request time: 0.451s | source
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transpute ◴[29 Jun 25 23:52 UTC] No.44417727[source]▶
More coverage of RF sensing, including laptops/phones with radios+NPU to sense their human:

2025, "Espargos: ESP32-based WiFi sensing array", 30 comments, https://news.ycombinator.com/item?id=43079023

2024, "How Wi-Fi sensing became usable to track people's movements", https://www.technologyreview.com/2024/02/27/1088154/wifi-sen...

2023, "What Is mmWave Radar?: Everything You Need to Know About FMCW", 30 comments, https://news.ycombinator.com/item?id=35312351

2022, "mmWave radar, you won't see it coming", 180 comments, https://news.ycombinator.com/item?id=30172647

2021, "The next big Wi-Fi standard is for sensing, not communication", 200 comments, https://news.ycombinator.com/item?id=29901587

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Animats ◴[30 Jun 25 03:37 UTC] No.44419092[source]▶
Right. The longer range versions of multistatic radar are used to detect stealth aircraft.[1][2] All that careful stealth geometry to minimize direct reflections doesn't help much when the emitters and receivers are in different locations.

[1] https://www.presstv.ir/Detail/2024/11/18/737423/guardians-of...

[2] https://www.yiminzhang.com/pdf/radar13_passive.pdf

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Grayskull ◴[30 Jun 25 09:10 UTC] No.44421093[source]▶
Well, you don't even need a radar. Tamara sensor could detect B-2, when it had it's onboard radar on.

https://en.wikipedia.org/wiki/Tamara_passive_sensor

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1. rcxdude ◴[30 Jun 25 12:20 UTC] No.44422369[source]▶
stealth does in general go out the window when you turn on your radar. It's much like dressing in black and then running around with a flashlight at night. (and yes, there are equivalents to the various forms of night vision here, with associated tradeoffs)
replies(1): >>44423144 #
2. engineer_22 ◴[30 Jun 25 13:39 UTC] No.44423144[source]▶
Nah, there is much secret about radar