Chateau LTE12 antenna gain

RouterOS Wireless Networking
1

Hi,

Chateau’s product specs tells us the following gain: see https://mikrotik.com/product/chateau_lte12

  • 2.4ghz → 3dbi
  • 5ghz → 4dbi

export - wireless section

/interface wireless
set [ find default-name=wlan1 ] band=2ghz-g/n channel-width=20/40mhz-XX country=austria disabled=no distance=indoors \
    frequency=auto installation=indoor mode=ap-bridge ssid=jupiter wireless-protocol=802.11
set [ find default-name=wlan2 ] band=5ghz-a/n/ac channel-width=20/40/80mhz-XXXX country=austria disabled=no distance=\
    indoors frequency=auto installation=indoor mode=ap-bridge ssid=jupiter wireless-protocol=802.11

Trying to set the antenna-gain on wlan2 to 4 is rejected:

[if@jupiter] /interface/wireless> set antenna-gain=4 wlan2
failure: minimal antenna-gain for this country is 6

/interface/wireless/monitor says, that wlan2 selected channel 5180/20-Ceee/ac/P(17dBm)

According to country-info 23dbm is possible for that channel:

[if@jupiter] /interface/wireless/info> country-info 
country: austria
  ranges: 2402-2482/b,g,gn20,gn40(20dBm)
          2417-2457/g-turbo(20dBm)
          5170-5250/a,an20,an40,ac20,ac40,ac80,ac160,ac80+80(23dBm)/passive,indoor
          5170-5330/a,an20,an40,ac20,ac40,ac80,ac160,ac80+80(20dBm)/dfs,passive,indoor
          5250-5330/a,an20,an40,ac20,ac40,ac80,ac160,ac80+80(20dBm)/dfs,passive,indoor
          5490-5710/a,an20,an40,ac20,ac40,ac80,ac160,ac80+80(27dBm)/dfs,passive
          5190-5310/a-turbo(20dBm)/dfs
          5180-5300/a-turbo(20dBm)/dfs
          5520-5680/a-turbo(27dBm)/dfs,passive
          5510-5670/a-turbo(27dBm)/dfs,passive
          902-927/b,g,g-turbo,gn20,gn40(30dBm)

Do I miss or misunderstood antenna-gain? And why I am not allowed to set an antenna-gain lower than 6?

2

Max is 23dBm on your country.
23dBm / 2 chain = Max 20dBm for chain (yes 20, is logaritmic)
You can not set antenna gain on values minors than the true gain hardcoded on software,
or values can cause you can transmit at more allowed power for your country.
On site are 4, but on brochure 5,5 , if software can not permit lower than 6, probably the brochure is correct.
The radio can transmit at 20 - 6 = 14 per chain, 14+14 = 17dbm, the sum of two chain.

3

That's one thing I do not understand.

As far I understood: when the hardware antenna-gain is 4dbi - it should be able to transmit at 23 (max allowed) - 4 (antenna gain) = 19dbm transmit-power. Not 17dbm. Or isn't it that easy?

4

If both antenna (if gain is 0) transmit at 23, the sum is 26…

Do not mix total with single chain… you have two antennas with two time the gain of 6

When ATPC on the device is unavailable, must transmit less than 3dB from the max allowed (only valid for 5GHz)

Also on Austria I can’t use my CB because is an International vesion, and if is set correctly to Austria laws,
Austria do not permit multi-selection device to be used…
Only special version exclusively for that country…

5

Makes sense.

For the 2ghz band it is allowed 20dbm. Here the easy calculation 20 - 3 = 17 works out. According to datasheet 2 chains too.

[if@jupiter] /interface/wireless> monitor 
numbers: wlan1
                 status: running-ap
                channel: 2452/20-Ce/gn(17dBm)
      wireless-protocol: 802.11
            noise-floor: -101dBm
         overall-tx-ccq: 84%
     registered-clients: 7
  authenticated-clients: 7
            wmm-enabled: yes
      current-tx-powers: 1Mbps:0(0/0),2Mbps:0(0/0),5.5Mbps:0(0/0),11Mbps:0(0/0),6Mbps:0(0/0),9Mbps:0(0/0),12Mbps:0(0/0),18Mbps:0(0/0),24Mbps:0(0/0),36Mbps:0(0/0),48Mbps:0(0/0),54Mbps:0(0/0),HT20-0:0(0/0),HT20-1:0(0/0),HT20-2:0(0/0),HT20-3:0(0/0),
                         HT20-4:0(0/0),HT20-5:0(0/0),HT20-6:0(0/0),HT20-7:0(0/0),HT40-0:0(0/0),HT40-1:0(0/0),HT40-2:0(0/0),HT40-3:0(0/0),HT40-4:0(0/0),HT40-5:0(0/0),HT40-6:0(0/0),HT40-7:0(0/0)
    notify-external-fdb: no
6

20 / 2 chain = 17dBm for chain (as reported) = 14dBm TX power + 3dBi antenna gain (for each chain)

On 2,4GHz ATPC rule are not applied
(Automatic Transmit Power Control)

7

Still I do not understand, why it is not allowed to set “antenna-gain” to 4 on wlan2?

In my understanding I just tell the device: “here, I have a 4dbi antenna”

The device says: “Thanks for informing me. Now I can lower/adjust TX-power to meet country regulation”

8

Because a maximum TX power is set for your country,
if is leaved possible decrease the antenna gain with a false value,
you can transmit more power than allowed,
but the antenna still has the real gain.

9

The post by @rextended above is not correct. This post together with this post by Normis tell everything about how actual Tx power takes into account different constraints (from wireless chip capability to country regulations).
Which means that ability to set certain antenna gain has nothing to do with country regulations.

And, BTW, the figure for 5GHz WiFi antenna gain @OP wrote (4dBi) is not correct according to information from product brochure for Chateau LTE12 … the correct value is 5.5 dBi and since UI does not allow setting antenna-gain to non-integer values, one has to enter 6dBi. Value 4dBi is valid for LTE antenna and LTE antenna has nothing to do with 5GHz WiFI antenna.

One thing, not explained in Normis’ post: Tx power (both setting and reading) on older chips (pre-ac) were about total power (for all Tx chains). On newer (ac and newer) Tx power is per chain, hence one has to do some maths depending on number of chains (add 3dB for dual-chains, add 5dB for tripple cains, 6dB for quadruple chains, etc). Country regulations are about total transmitted power which is sum of Tx powers of all transmitters active at any given time.

10

Your post above is not correct. :smiley:
Instead to say that, explain where and why, so I correct myself.
Only idiots think they have nothing more to learn.

The user read the official website here:
https://mikrotik.com/product/chateau_lte12
and not the brochure.
Is a MikroTik error.

I too was convinced that the antenna had that gain,
it’s not that I start to disassemble the products and go to the laboratory to measure if what is written is true…
I trust what is written on the site…

11

Your answer

Because on your country is set that max TX power.

relates to question in a post above yours

Still I do not understand, why it is not allowed to set “antenna-gain” to 4 on wlan2?

So this is the reason I think your answer is not correct.


And instead of reasoning why it’s wrong I gave two reference posts (by @Normis, who is Mikrotik employee and should know how Mikrotik devices do the calculations better than us, users). If you really want to understand why your answer is wrong, go and read the posts I linked.

Yes, I agree that error on product page is most probably the cause of OP’s problems.

12

I hope not misunderstand what you consider wrong, I modified the post:

Because a maximum TX power is set for your country,
if is leaved possible decrease the antenna gain with a false value,
you can transmit more power than allowed,
but the antenna still has the real gain.

13

I hate your habit of changing your own posts after some other user tells you it’s not correct. In long run you’re making users telling your posts are wrong look idiots because later readers won’t see what was wrong.

And, please, tell me which part of my post #9 above is not correct. If you’re making me an idiot you should at least provide some arguments for that. I argumented by claim your preceeding post was not correct in quite some details.

14

But if something is written wrong, I have to change it,
so as not to mislead those who read it later,
especially where it is marked as solved…

Strange that, instead of being happy that I accept your advice, you complain.

15

It’s about MikroTik error on write somethihg on website, (than is readed first than brochure) and other on brochure
You simply haven’t checked what OP’s link says first, but you think the only document that was read was the brochure
Wireless 2.4 GHz Max data rate 300 Mbit/s
Wireless 2.4 GHz number of chains 2
Wireless 2.4 GHz standards 802.11b/g/n
Antenna gain dBi for 2.4 GHz 3
Wireless 2.4 GHz chip model IPQ-4019
Wireless 2.4 GHz generation Wi-Fi 4
Wireless 5 GHz Max data rate 867 Mbit/s
Wireless 5 GHz number of chains 2
Wireless 5 GHz standards 802.11a/n/ac
Antenna gain dBi for 5 GHz 4Wireless 5 GHz chip model IPQ-4019
Wireless 5 GHz generation Wi-Fi 5

16

Your post above is not correct. > :smiley: >

Which part of my post is not correct? I even found the correct value for the 5GHz antenna gain (even though it’s burried inside product brochure). So you can’t claim my post is not correct, you can claim (and complain to MT) that their informations are not correct. And I never went into the source of OP’s numbers, I just provided link to source of correct value.

And BTW your (changed) post is still technically incorrect.
It’s been explained that devices with non-detachable WiFi antennae have their gain burned in ROM so that user can not set it lower. And that’s true for any country set (for regulatory reasons), even if it’s “no-country-set”. So the real reason is that it is not possible to set antenna gain to lower than what it really is and that user was mislead by MT information about real antenna gain value.

FYI: I was considering not to start this discussion (because I knew we’d have a lengthy one) and the only reason to start writing in this thread was the fact that @OP chose your (incorrect) answer as solution. I believe OP could change his mind and select another post as solution.

17

:cry:

18

First to clear things up for users that burry out this topic later:
ksnip_20210730-141858.png
vs
ksnip_20210730-142040.png
This topic would not exist, if I was aware of that 5.5dbi thing.

19

Correct, and also this:

I do not have one Chateau for test, but this are my Audience.
I can change antenna gain with lower value (or higher, not matter).
[rextended@AP Matrix] > /sys rou pri
routerboard: yes
board-name: Audience
model: RBD25G-5HPacQD2HPnD
serial-number: BBQCRX59A5D4
firmware-type: ipq4000
factory-firmware: 6.45.4
current-firmware: 6.47.9
upgrade-firmware: 6.47.9
[rextended@AP Matrix] > /int wire info
[rextended@AP Matrix] /interface wireless info> hw-info wlan1
ranges: 2312-2732/5/b,g,gn20,gn40
2484-2484/5/b,g,gn20,gn40
tx-chains: 0,1
rx-chains: 0,1
extra-info: pciinfo:0x0, cid:0, gain:4

[rextended@AP Matrix] /interface wireless info> hw-info wlan2
ranges: 5180-5320/5/a,an20,an40,ac20,ac40,ac80
tx-chains: 0,1
rx-chains: 0,1
extra-info: pciinfo:0x0, cid:1, gain:5

[rextended@AP Matrix] /interface wireless info> hw-info wlan3
ranges: 5500-5825/5/a,an20,an40,ac20,ac40,ac80,ac160,ac80-80
tx-chains: 0,1,2,3
rx-chains: 0,1,2,3
extra-info: pciinfo:0x0, cid:0, gain:4

[rextended@AP Matrix] /interface wireless info> country-info italy
ranges: 2402-2482/b,g,gn20,gn40(20dBm)
2417-2457/g-turbo(20dBm)
5170-5250/a,an20,an40,ac20,ac40,ac80,ac160,ac80+80(23dBm)/passive,indoor
5170-5330/a,an20,an40,ac20,ac40,ac80,ac160,ac80+80(20dBm)/dfs,passive,indoor
5250-5330/a,an20,an40,ac20,ac40,ac80,ac160,ac80+80(20dBm)/dfs,passive,indoor
5490-5710/a,an20,an40,ac20,ac40,ac80,ac160,ac80+80(27dBm)/dfs,passive
5190-5310/a-turbo(20dBm)/dfs
5180-5300/a-turbo(20dBm)/dfs
5520-5680/a-turbo(27dBm)/dfs,passive
5510-5670/a-turbo(27dBm)/dfs,passive
902-927/b,g,g-turbo,gn20,gn40(30dBm)

[rextended@AP Matrix] > /int wire
[rextended@AP Matrix] /interface wireless>:put [get wlan1 antenna-gain]
4
[rextended@AP Matrix] /interface wireless>:put [get wlan2 antenna-gain]
5
[rextended@AP Matrix] /interface wireless>:put [get wlan3 antenna-gain]
4
[rextended@AP Matrix] /interface wireless> set [find] antenna-gain=1
[rextended@AP Matrix] /interface wireless>:put [get wlan1 antenna-gain]
1
[rextended@AP Matrix] /interface wireless>:put [get wlan2 antenna-gain]
1
[rextended@AP Matrix] /interface wireless>:put [get wlan3 antenna-gain]
1
[rextended@AP Matrix] /interface wireless> set [find] antenna-gain=4
[rextended@AP Matrix] /interface wireless> set wlan2 antenna-gain=5
[rextended@AP Matrix] /interface wireless>:put [get wlan1 antenna-gain]
4
[rextended@AP Matrix] /interface wireless>:put [get wlan2 antenna-gain]
5
[rextended@AP Matrix] /interface wireless>:put [get wlan3 antenna-gain]
4
[rextended@AP Matrix] /interface wireless>

20

I even found the correct value for the 5GHz antenna gain (even though it’s burried inside product brochure).

Two different sources from Mikrotik. One PDF, one product page. 1:1. And who decides what value is the correct one? My trust in product-specs from a product-page are way more solid than into ROS v7 beta. It could have been a bug - resulting in lower TX-power than it would be allowed.