We are considering .a for use in the UK in a wISP.
(5725 to 5850 GHz)
We have already found Mikrotik supports the mandatory DFS in the .a band, but does it support TPC as well??
I can find no reference to this in the manual.
Many thanks..
If you are anything like me billr, you assumed that the UK requirement was for automatic transmit power control. But it's not, you just need to be able to vary the power output within the limits quoted in IR2007. Having said that there is no requirement to ever set the power below 2W! A typical bit of UK legislation really.
The responsible thing to do would be to only use the power you need for shorter links but I would have to be getting a very good level to give up fade margin.
Please share your experiences if you start using the 5.8 GHz band in the UK with MT as there are at least a couple of us that are in the same boat on this forum.
The responsible thing to do would be to only use the power you need for shorter links but I would have to be getting a very good level to give up fade margin.
Please share your experiences if you start using the 5.8 GHz band in the UK with MT as there are at least a couple of us that are in the same boat on this forum.
GJS... THANKS !!
Bill is the name - R is the surname
)
I initially assumed automatic TPC BUT I have re read the (very unclear) document) and come to the same conclusion.
ALL you need is to be able to VARY power output.
Verry simple !!
SO it is actually in 2.8 (you can very power output !!)
So we are well out of the woods. As you say responsible radio practise is to use the lowest power to give a usable link. MANY thanks..
PS will share when we get going. Been using b ang g until now.
Bill is the name - R is the surname
)I initially assumed automatic TPC BUT I have re read the (very unclear) document) and come to the same conclusion.
ALL you need is to be able to VARY power output.
Verry simple !!
SO it is actually in 2.8 (you can very power output !!)
So we are well out of the woods. As you say responsible radio practise is to use the lowest power to give a usable link. MANY thanks..
PS will share when we get going. Been using b ang g until now.
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stephenpatrick
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RE 2.8 GHz no I do NOT think DFS or anything else is needed in this band..
RE 5.8 GHz it IS 2 W eirp
Look on the Ofcom site.
a) 'The Authorisation Regime for Fixed Broadband Services operating in the frequency range 5725 - 5875 MHz (band C)'
b) 'UK Radio Frequency Requirement 2007
Fixed Broadband Services operating in the frequency range 5725 - 5875 MHz'
That's the documents you want.
In b) look at TABLE 2.1, where it specifies DFS and a bit about TPC.
HTH, Bill
RE 5.8 GHz it IS 2 W eirp
Look on the Ofcom site.
a) 'The Authorisation Regime for Fixed Broadband Services operating in the frequency range 5725 - 5875 MHz (band C)'
b) 'UK Radio Frequency Requirement 2007
Fixed Broadband Services operating in the frequency range 5725 - 5875 MHz'
That's the documents you want.
In b) look at TABLE 2.1, where it specifies DFS and a bit about TPC.
HTH, Bill
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stephenpatrick
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2.8 = RouterOS 2.8. I don't think that had DFS, i.e. you can't use it legally in the UK or other parts of EU.
2.4GHz = no you don't need TPC or DFS so RouterOS2.8 is fine.
5.8GHz = yes you need RouterOS 2.9.
2W EIRP, well is this calculation correct?
100mW radio = 20dBm (yes I know most are 65mW or less)
2W EIRP limit = 33 dBm
So any more than 13dB antenna, you exceed the EIRP, right?
Please comment or correct me ...
2.4GHz = no you don't need TPC or DFS so RouterOS2.8 is fine.
5.8GHz = yes you need RouterOS 2.9.
2W EIRP, well is this calculation correct?
100mW radio = 20dBm (yes I know most are 65mW or less)
2W EIRP limit = 33 dBm
So any more than 13dB antenna, you exceed the EIRP, right?
Please comment or correct me ...
Re your 5.8 GHz calculation on the face of it , it is right..
BUT remember:
a) Cable loss (0.3 dB /m or so....)
b) Connector loss (0.1 or 0.2 dB per connector at least ??)
You can easily lose 3-6 dB if you have a long cable run and several connectors - and a poor quality tail connecting to the radio card..
So you CAN have higher powered radios and higher gain antennas and still meet the requirements, provided if anyone asks you can show you calculations. You just have to juggle the radio power and the antenna gain.
BTW V 2.8 HAS DFS - I am looking at it now !!
BUT remember:
a) Cable loss (0.3 dB /m or so....)
b) Connector loss (0.1 or 0.2 dB per connector at least ??)
You can easily lose 3-6 dB if you have a long cable run and several connectors - and a poor quality tail connecting to the radio card..
So you CAN have higher powered radios and higher gain antennas and still meet the requirements, provided if anyone asks you can show you calculations. You just have to juggle the radio power and the antenna gain.
BTW V 2.8 HAS DFS - I am looking at it now !!
Gents,
Your EIRP calculations are correct. What I have found though, is that if you are doing PTMP and planning to use an Omni at your AP, the gain of the antenna becomes the limiting factor. e.g.
20dBm from radio + 10dBi antenna - 1dB feeder losses
Same applies to receive sensitivity with this antenna gain. That is why I am getting the Ubiquiti SR-5 card (23dBm o/p plus good sensitivity) and plan to use this in the AP with CM9s and 19dBi panels in the CPE.
That's the plan anyway...
Just waiting for some RB500s to arrive now to start experimenting.
Your EIRP calculations are correct. What I have found though, is that if you are doing PTMP and planning to use an Omni at your AP, the gain of the antenna becomes the limiting factor. e.g.
20dBm from radio + 10dBi antenna - 1dB feeder losses
Same applies to receive sensitivity with this antenna gain. That is why I am getting the Ubiquiti SR-5 card (23dBm o/p plus good sensitivity) and plan to use this in the AP with CM9s and 19dBi panels in the CPE.
That's the plan anyway...
Just waiting for some RB500s to arrive now to start experimenting.
SLIGHTLY off topic.
With my heart in my mouth, I have upgraded to 2.9rc2.
IT WORKS !!
It takes quite a while to sort itself out so you have to be patient, but as far as I can see none of my rules have been lost or corrupted..
THE RADIO bit - has been CONSIDERABLY upgraded.
The DFS is (still) there, there is an option for setting Country (regulatory domain), TPC is explicitly included, etc ...
The point I am making is, provided this is stable, as far as I can see - this will do **everything** and more for 5.8 GHz in the UK.
Cheers all.
With my heart in my mouth, I have upgraded to 2.9rc2.
IT WORKS !!
It takes quite a while to sort itself out so you have to be patient, but as far as I can see none of my rules have been lost or corrupted..
THE RADIO bit - has been CONSIDERABLY upgraded.
The DFS is (still) there, there is an option for setting Country (regulatory domain), TPC is explicitly included, etc ...
The point I am making is, provided this is stable, as far as I can see - this will do **everything** and more for 5.8 GHz in the UK.
Cheers all.
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stephenpatrick
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Hi, what a great "UK thread" we're generating ...
Another UK question, is "Turbo mode" legal ? (uses channel bonding)
i.e. does OFCOM stipulate what channel widths are allowed in the 5.8GHz band ?
Also relevant elsewhere in Europe, I heard it's not allowed in at least one country.
Regarding "Country setting", I wonder if that's taken from wireless access points (indoor use), which use the 5.3GHz band in the UK I believe.
Regards
Another UK question, is "Turbo mode" legal ? (uses channel bonding)
i.e. does OFCOM stipulate what channel widths are allowed in the 5.8GHz band ?
Also relevant elsewhere in Europe, I heard it's not allowed in at least one country.
Regarding "Country setting", I wonder if that's taken from wireless access points (indoor use), which use the 5.3GHz band in the UK I believe.
Regards
Yes, I believe if you select UK country you will get 5.3 ISM, license free but 200mW and nomadic use only. The whole attraction of band C for me is to be in a band where you cannot walk in to PC World and come out interfering with me.
Regarding channel bonding and Bill's comment on getting the UK channels, IR2007 only has a 'suggested' channel plan so it is not neccesary to hit any particular frequency nor is there a limit on channel width i.e. bonding, though the latter is my assumption only.
By the way, there is also a 'notch' of dissallowed spectrum in the middle of the band which is currently allocated to road transport telemetry. This allocation is being reviewed by Ofcom at the end of this year when they will hopefully release it which will give us another two 20MHz channels. Lets make sure we all lobby Ofcom nearer the time for release of the spectrum.
Cheers.
Regarding channel bonding and Bill's comment on getting the UK channels, IR2007 only has a 'suggested' channel plan so it is not neccesary to hit any particular frequency nor is there a limit on channel width i.e. bonding, though the latter is my assumption only.
By the way, there is also a 'notch' of dissallowed spectrum in the middle of the band which is currently allocated to road transport telemetry. This allocation is being reviewed by Ofcom at the end of this year when they will hopefully release it which will give us another two 20MHz channels. Lets make sure we all lobby Ofcom nearer the time for release of the spectrum.
Cheers.
IR 2007 is not the most **transparent** of documents..
I think you are right about frequencies and channels - in annex A there is an Informative table (I actually work in standards .... and informative means NOT mandatory - for information) - showing example channel plans - for 5, 10 and 20 MHz.... It shows example channel centre frequencies.
It's all very confusing. I get the impresion OFCOM are not that clear themselves)
Re channel width I think the limit is 100 mW/MHz ie (guess !!) 5 MHz channel = 500 mW total power over 5 MHz. So provided the limit of 100 mW/MHz is achieved I would assume channel bonding is ok..
Cheers !
PS GJS - WHERE ARE YOU getting the super cards from please !!?? The Ubiquiti ones. They look wonderful !! The SR5 cards, I have been looking a them for several weeks.. http://www.ubiquiti-networks.com/sr5/index.htm
400 mW !! Now shipping it says..
I think you are right about frequencies and channels - in annex A there is an Informative table (I actually work in standards .... and informative means NOT mandatory - for information) - showing example channel plans - for 5, 10 and 20 MHz.... It shows example channel centre frequencies.
It's all very confusing. I get the impresion OFCOM are not that clear themselves
)Re channel width I think the limit is 100 mW/MHz ie (guess !!) 5 MHz channel = 500 mW total power over 5 MHz. So provided the limit of 100 mW/MHz is achieved I would assume channel bonding is ok..
Cheers !
PS GJS - WHERE ARE YOU getting the super cards from please !!?? The Ubiquiti ones. They look wonderful !! The SR5 cards, I have been looking a them for several weeks.. http://www.ubiquiti-networks.com/sr5/index.htm
400 mW !! Now shipping it says..
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stephenpatrick
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Well that's potentially great news if we can use Turbo mode in the UK. Well worth checking.
I note Othogon annouced a ">300Mbps" radio which again presumably gobbles up the entire 5.8 spectrum to achieve it - wonder if they get type approval -
Ubiquity and any other cards, related to our "EIRP discussion above", note that the power droops at high modulation rates - the 400mW is at the slowest speed - so that's bad news for omni antennas but better news for P2P links, less chance of exceeding EIRP with a 23dBi flat plate and 54Mbps OFDM running. Same's true of CM9's and similar 65mW radios - you don't get anywhere near that power in high speed modes.
Regards
I note Othogon annouced a ">300Mbps" radio which again presumably gobbles up the entire 5.8 spectrum to achieve it - wonder if they get type approval -
Ubiquity and any other cards, related to our "EIRP discussion above", note that the power droops at high modulation rates - the 400mW is at the slowest speed - so that's bad news for omni antennas but better news for P2P links, less chance of exceeding EIRP with a 23dBi flat plate and 54Mbps OFDM running. Same's true of CM9's and similar 65mW radios - you don't get anywhere near that power in high speed modes.
Regards
Stephen - You're quite right in that in a practical scenario you won't be seeing 400mW from the card. What I have done though is a link budget with an 11dBi omni on an AP and 19dBi panel on the CPE. Putting CM9 figures into the CPE and SR-5 figures into the AP the link was quite nicely balanced. I think I used the numbers for 24Mbps which I would think would comfortably give 10Mbps of real throughput without using turbo mode.
When the hardware arrives I'm going to set up a temporary link with these antennas and CM9 cards then swap for the SR-5 at the AP end and see what difference it makes to RSSI at both ends.
Bill - Drop me an email at guy dot smith at zen dot co dot uk regarding SR-5 card sourcing.
When the hardware arrives I'm going to set up a temporary link with these antennas and CM9 cards then swap for the SR-5 at the AP end and see what difference it makes to RSSI at both ends.
Bill - Drop me an email at guy dot smith at zen dot co dot uk regarding SR-5 card sourcing.