NR ARFCN calculation

5G NR
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1

Is this NR ARFCN correct for 3500-3600 MHz Spectrum for SA.

Screenshot_20221028-140508_Network Signal Guru~2
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2

As shows your App from screenshot and any “ARFCN Calculator Online” on the internet, this NR-ARFCN 634080 is equal to 3511.2 MHz frequency that is in range 3500 - 3600 MHz. Everything is correct from this point of view. Nevertheless I can’t confirm that this NR-ARFCN should be used in your network, because I don’t know what NR-ARFCNs your operator is using

3

They hold 3500-3600MHz spectrum from what I’ve seen on LTE center frequency should be ARFCN for example 3550MHz for 3500-3600 but they’re using 3511

4

634080 ia the SSB ARFCN not the NR-ARFCN
The tool does not show the NR-ARFCN

5

NR ARFCN is 634050

Screenshot_20221029-160320_Network Signal Guru
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6

What does 8 ports mean?
Csi-rs?

7

Actually there are two types of NR-ARFCN that are using in practice for 5G.

  1. SSB NR-ARFCN that shows central frequency of SSB (Synchronization Signal Block)
  2. NR-ARFCN (or Absolute NR-ARFCN) that shows central frequency of bandwidth (this is 3550 in your example)

In 5G SSB is not located in the center of channel bandwidth, it has some offset. It’s location is nearer to bandwidth edge. Your tool from screenshot is showing exactly SSB NR-ARFCN and it’s absolutely normal that it’s position is not in the center of bandwidth

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8

No, idk why it’s showing 8 Ports but it’s 32TRx 2nd Gen Nokia Massive Mimo

9

For Ericsson it seems to show 32 ports properly

10

But the NR ARFCN is 634050 (3510.8MHz) it should be around 3550MHz right?

11

Right! Unfortunately, I have no answer why does it shows 3510.8MHz :smile:
UPD: The answer is: it’s not in 3500 - 3600 MHz range

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12

Well they hold 3500-3600 only in my region but I read somewhere that SA ARFCN cannot be center frequency

13

@RK21
This is not accurate.
First of all, NR-ARFCN is same whether it is SA or NSA
Second, if the center frequency of 3.5GHz bandwidth is divisible by 30 KHz then it is the NR-ARFCN, otherwise the next closed possible ARFCN is used

In your case, the center frequency is 3550 MHz is not divisible by 30 KHz so it cannot be NR-ARFCN and the NR-ARFCN is at 3550.02 MHz which is 636668

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14

If that’s the case it should be causing interference to other operator as they’re holding 3400-3500

15

With NR-ARFCN at 3550.02MHz and BW of 100 MHz, the 3GPP min gaurd bands are neing met and no interference is expected

Please refer to 3GPP 38.101-1 for the difference between N_REF nad SS_REF