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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
AE6XE's picture
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
K6AH's picture
Ubiquiti could also be

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

K0OP
ARRL article from 2018

Greetings, first time posting on the forum.  We had a club meeting tonight (Red River Radio Amateurs, rrra.org) and we have the funding and location for adding to our existing 3 backbones of AREDN.  The backbone uses the rocket m3's.  Someone brought up the fact that the rocket as it's been in the past will no longer be available.  I haven't checked with Streakwave or any other vendor about availability.  We're tying to decide if we still go with the rocket or seek some non-AREDN way to haul the data at the backbone locations?  I did find this article from the ARRL...  http://www.arrl.org/news/ntia-targets-portion-of-3-4-ghz-band-for-potential-wireless-broadband-use
We'd like to know what other groups are doing or going to do.  Perhaps the possible unavailability of the rocket and the fact that 3Ghz spectrum potentially not usuable, is still too new.

Steve - K0OP

nc8q
nc8q's picture
fact.: There is a proposal in-process.

It may already be common knowledge, but...
Here is a link to a letter released by the
United States Department of Commerce,
National Telecommunications and Information Administration
dated August 01, 2019,
regarding the spectrum 3150-3550 MHz:
https://www.ntia.gov/other-publication/2019/review-current-frequency-ass...

Regarding Appendix B,
How do I obtain a Serial Assignment Number in the Government Master File
from the Frequency Assignment Subcommittee,
so that I can file the existence and usage of my 3.4 GHz devices?
:-|

Chuck

K5DLQ
K5DLQ's picture
I think @k6ah just ordered

I think @k6ah just ordered 3Ghz gear and received it already.  It's still available.

K6AH
K6AH's picture
3GHz Gear

I recently (past 3 weeks) ordered 3 ea. 3 GHz Rockets.  A quick check of eBay returns several vendors offering new devices.  I suspect Ubiquiti will eventually obsolete these in favor of gear for the new Citizen's Band at 3.9 GHz and above.  If this happens we will either code support fo them, or encourage a migration to 5 GHz.  We could also explore adding a transverter to 5 GHz devices (which is actually what the current 3 GHz devices are).

K6CCC
K6CCC's picture
What about antennas?

I have seen several sources of 3GHz radios, but nothing for antennas.  You have a source?
 

ke6bxt
ke6bxt's picture
https://www.ebay.com/itm
K6CCC
K6CCC's picture
Thanks Don

Two (all he had) purchased.

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