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3GHz equipment

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AE6XE
AE6XE's picture
3GHz equipment

This is a recent dialog a mesh'er purchasing a Rocket M3 device had with StreakWave:

mesh'er:  Can you tell me the status of that device?
Streakware:   not on the ship yet. ...  they might be  updating the  Rocket m3. Oct 20 it has to fall into the  new regulation. 
mesh'er:  What new regulation?
Streakware:  What I was told  in 2020 those units  will have to shut down if there’s military operation going on.

Anyone know of the FCC references to confirm?   This would be like DFS channels and radio behavior in 5GHZ part 15 device certification.   Military radar is primary in part 97 3GHz allocation.

Joe AE6XE

KE2N
KE2N's picture
3 GHz here

"more than 10 available" on eBay from a seller in Florida.  I bought one a few weeks back.  I still see them there.
 = = 
The usual frequency for the 3GHz navigation radar here is above the top of our band (3.51 GHz).   
I am guessing the only run it during IFR conditions because I did not see it last time I looked.
If you are near their frequency and have LOS when they turn it on, don't worry, you will  be off the air - the front end of these radios will see the signal at some significant offset and be de-sensed..  Ground-mounted installations apparently run megawatt ERP's (microsecond pulses).   

 

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AE6XE
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Maybe only the M365 devices,

Maybe only the M365 devices, not supported by AREDN, are impacted?

The last time I looked at radar pulses like this, it seemed to me that an 802.11n signal wouldn't really notice it.   While the radar 'pulse' has very high power, it is such short duration, that it would only interfere with a symbol in OFDM.   ...and wow would it blow that symbol away with that power.   However, the average power of the radar over say 1 second, is relatively very low power.   The transmitter probably has to wait for the max reach of the radar before transmitting the next pulse, or it would clobber receiving the reflections.  

Forward Error Correction, or packet retry, would occur like any other lost symbol in the protocol for 802.11n.    The radar pulses have to wait for the signal to travel 100, 200 mi, or so, then bounce back.  Probably the radar max distances are classified to detect an incoming threat?    This is a very long time to wait relative to the time of the pulse itself.   The received pulse reflections would be very low power signals at the max distances.  Any nearby 802.11n signals constantly transmitting could interfere.  

K6AH
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Ubiquiti could also be

Ubiquiti could also be incorporating the new Citizen's Broadband service into the new M3 version.

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