ESP8266 Community Forum

- Sat Jun 17, 2017 9:57 am #67274 Yeah, there's so much else I need to be getting on with, but these little radar sensors are weirdly addictive.

I tried using 2 at the same time triggering different interrupts, about 4m apart, to see if It was possible to get stereo directional clues for triggers.

Always seemed to give the same result, and wasn't totally sure of which sensor was running the show - so I disconnected the output of the nearest sensor to its gpio... and it still caused triggered alerts via the remaining sensor (which was shielded by metal from the trigger source).

It seems that just by being powered up it's still emitting a doppler shifted microwave signal that the other connected sensor was interacting with to cause an alert ... almost like quantum entanglement!

Scrambled my brain for a while... but makes me wonder if it's feasible to set up an interactive radar field or 'fog' to cover a wider area... that's what I mean about weirdly addictive.

Where to get modules?

https://www.banggood.com/custlink/KvGGhGF4wG

- Sat Jun 17, 2017 10:31 am #67277 That's awesome mate, does the parabolic dish not make the beam very narrow at the 40 meter range?

This could be greatly improved, I have built microwave links over 20 miles, the dish you are using is for 10 Ghz X-band. Making a dish for the 3 Ghz band would extend the range massively. Love the idea

Dans

- Sat Jun 17, 2017 11:14 am #67279 The old sat dish is not active of course, simply being used as a reflective parabola, so even a metal dustbin lid would probably do a similar job.

Beam distance and width ought to be adjustable by mounting the radar sensor closer or farther from the parabola focal point - I just wacked it on the external LNB cover with 3 bits of insulation tape, which was far from optimal.

A future experiment might be to try mounting 2 sensers together at right-angles to each other to see if that makes things better or worse.

At 40m the beam is about 1m to 2m wide, which makes it handy as a single-ended wider beam-break equivalent, or perhaps mounted high enough to be beamed down on a target door or vehicle etc without being triggered by anything closer and lower.

If a target was converged by 2 beams from different directions it could offer pinpointed spot trigger zone capability.

Where to get modules?

https://www.banggood.com/custlink/KvGGhGF4wG

- Sun Jun 18, 2017 1:16 pm #67321 @Electroguard

Many thanks for sharing the results of you very interesting experiments with the Radar Detector.

I find the long distance tests quite impressive, but I'm interested to know how the Detector would behave on short distance.

More specific, I wonder if the detector would function as a reliable rain-detector.

Do you think the detector will trigger if you splash a few drops of water on the lid of the waterproof box?

Can I interest you in performing such a test?

Anyhow, thanks for the inspiration!