Public Safety Licensed 4.9 GHz Max EIRP

I was wondering if anyone out there could provide some clarification on the max EIRP limits for the Public Safety Licensed 4.9 GHz spectrum?

High power maximum conducted output power (dBm) = 33

(2) “High power devices are also limited to a peak power spectral density of 21 dBm per one MHz. High power devices using channel bandwidths other than those listed above are permitted; however, they are limited to peak power spectral density of 21 dBm/MHz. If transmitting antennas of directional gain greater than 9 dBi are used, both the maximum conducted output power and the peak power spectral densityshould be reduced by the amount in decibels that the directional gain of the antenna exceeds 9 dBi. However, high power point-to-point and point-to-multipoint operations (both fixed and temporary-fixed rapid deployment) may employ transmitting antennas with directional gain up to 26 dBi without any corresponding reduction in the maximum conducted output power or spectral density. Corresponding reduction in the maximum conducted output power and peakpower spectral density should be the amount in decibels that the directional gain of the antenna exceeds 26 dBi”.

Using a 20 MHz wide channel (max for this spectrum) it looks like from what I am reading you can go up to an EIRP of 59 dBm.

Any feedback on this would be greatly appreciated.

I found this site in my own research about 4.9: http://urgentcomm.com/rebanding/radio_introduction_ghz

they have this table:
image

Which was corroborated by Colorado’s (My home state!) own study:
http://ntiaotiant2.ntia.doc.gov/top/docs/eval/pdf/086004010e.pdf (page D14)

My guess is that Mimosa’s equipment is certified for the Low power device (FCC Mask L) because that portion of the licensing is most similar to 802.11. The FCC Mask M devices have pretty stringent isolation requirements. Mimosa’s own paperwork says it will only do 20 MHz in the 4.9. I would be willing to bet that you are limited to 20 dBm transmit power with a 9 dBm antenna and corresponding decreases with higher antenna gains.

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Thank you for the response. I also read through the same info you cited. I guess what I really need to determine is what FCC Mask the Mimosa equipment falls under, which would make things pretty clear at that point.

Hi @Ethan,

I did some research and found that Mimosa equipment should be under FCC Mask M. The following data is what I used to determine that:

Edit: Corrected PTMP and PTP info for clarification.

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Thank you for the information. Much appreciated.

You’re very welcome.

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I know this is pretty old topic. When choosing the public safety band, what do you need to do when initially configuring the radio? These are replacing some older Alvarion PTP links for Fire and rescue.

Let me know. I don’t have the radios in hand yet. Just wanted my ducks in row before getting them in hand.

Thanks all,

No problem, when you go to unlock your radios, you need to have United States Licensed as an option.

To do that you have to go into your account on Mimosa Cloud then go to Account Settings by clicking on your Name Character Thingy then scroll all the way down to Add Country. Then add “United States Licensed” (Though it could have been combined with “United States” we did ours before Mimosa changed up their system. I don’t see United States Licensed as an option, but maybe it is only there if you don’t have it already…)

So I have United States, but I don’t believe I have United States with “operate Licensed”.

When I go to try and add United States and check “operate under licensed” it states I already have USA and won’t allow me to add it.

Do I need to delete it? If so, how do I do that?

I have added US Licensed to your account. Could you check and make sure it’s available please?

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Hi Nathaniel,

Once you have logged into you account, go to the “Manage” page.

In the upper right hand corner drop down where it shows your name, or whatever you have named you networks, open the drop down and click on “Network Settings”

On the right hand side of this page it should have the “Countries” section ( you will probably already have United States). You should see a “+ Add County Code to Network” button underneath that. Click that and then scroll down and find “United States Licensed” and you should be able to select it. Then you should be able to proceed with adding your address and so forth to complete the set up.

Nathaniel Lyon via Mimosa Community mimosa@discoursemail.com 1/29/2019 11:19 AM >>>


Nathaniel

    January 29

So I have United States, but I don’t believe I have United States with “operate Licensed”.

When I go to try and add United States and check “operate under licensed” it states I already have USA and won’t allow me to add it.

Do I need to delete it? If so, how do I do that?

I think an Admin added it for me. LOL. I logged in this AM and it was there with a California address (not where we are located) and some other stuff I wouldn’t have put in.

Thanks whoever fixed that for me!

Ya, I think it’s changed since when we setup our account. It seems that you need to contact Mimosa to get that changed…

I have to be honest, we don’t run much Mimosa gear. We tried several years ago with a PTP link. The link lasted 1 day and it died. :frowning:

Today, can you take a CPE and put it into router mode? I know the last time I was in the Gui I don’t think that was possible.

Nope, all CPE are smart Layer 2 bridges. No routing is made available in the GUI. The only product that has routing is the G2. From what I understand it’s pretty basic as far as that goes.

Though to be honest, I prefer it that way, it’s less flexible, but I think that is what has bitten a lot of other companies in the bum. Too many features trying to do too many things. We have never trusted any of our CPE radios to do much beyond Layer 2 bridging just because they really don’t have much horsepower.