Hi, apparently my previous post (http://forum.mikrotik.com/viewtopic.php?f=7&t=98137) was a bit to extensive.
We suffer from a neighbor with high power antennas destroying our network in the 2,4GHz spectrum.
We asked the authorities to assist us in proving that they are sending way beyond legal boundaries. In Denmark, we are obliged to stay below 100mW transmitting power in the 2,4GHz band.
The signal from our "neighbor" is used by a WISP to provide 4-8km access to clients using Ubiquity equipment. My common sense tell me immediately that this is simply not possible in the 2,4GHz band as 100mW would not allow access beyond max a few hundred meters.
To complicate things, they try to hide the signal by using "in between channel frequencies" and by using non 802.11 protocols.
We discovered the interference immediately when the system was started, our upload went from fantastic to almost non-existent. We even got them to turn off the signal for a short period of time and this immediately solved the problem - until the system was powered on again.
Luckily for us, the Mikrotik Routerboards come with a nice build-in spectrum analyzer that helped us "see the noise" - thanks guys!
The antennas are located 500m away but still we see a -40 to -20 dBm signal using a MT SXT (500m away).
The "specialist" from the authority came with an expensive spectral analyzer and measured -62dBm in that distance and calculated that that was within legal boundaries.
We then asked him to measure on 2 of our MT Groove 2,4 GHz with a 6dB antenna attached and adjusted for this (TX power reduced as described in all MT documentation). He concluded that we could easily turn up the power as it was VERY low.
I then turned the power up to max and removed the damping for the 6dB antenna - in my calculations, this would give me a 1W x 6dB = 4W e.i.r.p.
He concluded that we were just below legal boundary and that we could send even stronger - at least double, maybe a bit more.
I know by experience that this would allow me access on a SXT from 4-6km distance with a fine bandwidth.
I do not know where to turn.
Either Mikrotik is "dead wrong" about the effect from the radio in the Groove (spec's state 1W - according to the "measurements" it should be more like 25mW at max power (I know this is not true) - or the way the authorities measure is simply wrong.
I am dealing with the highest authority in Denmark that is very close to "blue stamping" illegal use of the ISM band here with 10W effect and I am not "educated" enough in radio technology to point him to the documentation that proves that he is dead wrong. Anyone? Please? links to official documentation on how to measure the e.i.r.p correctly?
As I recall it, it should be measured as "radiated effect on a well defined surface in a very short distance" - But then again, I may be utterly wrong!
Even though it could seem attractive to be able to use the 2,4GHz for long distance links "legally", it would ruin the future for our net of 20 masts giving free access for more that 1.000 people on our camping site just to give access to a few customers on "the noise generator" - I dare not think of the consequences when this become commonly known. It would mean that anyone could set up 10W e.i.r.p transmitters in the ISM band "legally" all over the cities. This would potentially destroy any and all access to the 2,4GHz band in Denmark.
Also a solid investment in a lot of fine MT wireless equipment would be wasted. Masts are interconnected by 5GHz MIMO Sextants carrying 300/300mbps without problems and the site is fed with a 1/1Gbps fiber. However the "last meter" may only gain as low as 100kbps upload because of the intruder.
We need help to prove the "expert" wrong.
Thanks in advance.
/Nisse