sunshineh wrote

But unfortunately also with this settings I only get a max. Speed of 7.2Mbps instead of 15Mbps with the old TP-Link Wireless AP WA5210G and the hypergain backfire antenna from l-com (Allnet).

What says the built-in speed test if you test pure wireless speed between the two WBS?

A)But how can I buy it if 24dBi, because it is not allowed in Germany? Or is it possible to reduce the power to 20dBi by your software in the WBS210?

Kaufen kannst immer alles. Use a cable such as the TL-ANT24EC5S, which has an attenuation of 4.5dBm, and set the antenna gain to 20dBi. Two of them would be needed for two connectors of the antenna/WBS.

B)The antenna size of 65cm is very big, so can you recommend a smaller external MIMO antenna with about 25cm?

Can't recommend some other, since I use TP-Link antennas only and the 2424MD is already half the size of the 2424B and 2415MS, which I use with WBS. ;)

C)Is the material of the dish/bowl metal? ...so that no radiation/emission (2.4GHz) goes back into the building where it is mounted on the wall. The radiation should only go away from the building.

Should be metal, otherwise you couldn't get such a directionality this antenna has ...

D)What influence does this electromagnetic field / radiation from the antenna has on people?

No idea. I only know that radiation from the sun, which is higher than that of a distant WiFi antenna, makes people completely freak out on sunny days such as today, especially if they drive a car. :D

Seriously, if you really care about radiation, see: http://forum.tp-link.com/showthread.php?90185-Why-is-it-impossible-to-reduce-the-transmit-power-of-the-router-TP-LINK-TL-WR741ND&p=190265&viewfull=1#post190265

sunshineh wrote

Now i called the TP-Link Support , and they told me that for my purpose "variant 3" would be the best choice:

Yes, CPE510 would certainly fit, too. How did you measure the 2.9km?

WHAT IS YOUR OPINION IF YOU SEE THIS PICTURE OF THE DISTANCE OF 2.9km????? Side A is where the photograph stands and side B is where the little red dot is placed.

Good line of sight, which is most important.

AND PLEASE GIVE US A SERIOUS ANSWER TO THE FOLLOWING QUESTIONs
...also compared 2,4GHz to 5GHz and a WBS210 (with external antenna) or a CPE210 (with internal antenna)

WBS510: up to 15km with sector antenna, up to 50km with dish antenna (both overkill for this distance).
WBS210: up to 5km with sector antenna, up to 30km with disk antenna, else same applies as for WBS510.
CPE510: up to 15km with internal antenna.
CPE210: up to 5km with internal antenna.

But note, that for legal EIRP limits in Germany (20dBm) the max. distance could be shorter.

Even more important: since the 2.4 GHz band is overcrowded in most areas, I prefer 5 GHz devices for direct radio links. To give you an idea: On a 1km link I get 70 Mbit/s wireless througput (about 45 to 50 Mbit/s data throughput if 802.11n is used) with a CPE510, while on the same link I could only achieve ~3-5 Mbit/s data throughput with a CPE210 due to limited AirTime in the 2.4GHz frequency band. Big difference!

As for the radiation backwards of the antennas, see the antenna patterns in the CPE data sheets. If you really want to find out exact figures of radiation in dBm at your place, you have to do professional measurements, which are very expensive.

Data sheet/antenna patterns for CPE210/CPE510: http://static.tp-link.com/CPE_Series_Datasheet_V1.pdf
Data sheet/antenna patterns for the TP-Link sector antennas: http://static.tp-link.com/TL-ANT2415MS-TL-ANT5819MS _V2_Datasheet.pdf
Data sheet/antenna patterns for the TP-Link dish antennas: http://static.tp-link.com/TL-ANT2424MD & TL-ANT5830MD_V2_Datasheet.pdf

sunshineh wrote

So in my case i guess i could reach 50Mbit/s over 3km????

Should be possible, but depends on a lot of factors to consider such as setup, antenna alignment, possible interferences at your place (radar) and even the weather.

...the graphic with the radiation is not very helpfull.

It is quite helpful if you understand how to read those diagrams! A circle is not kilometers, but attenuation in dBm. So for example, in:







I can see that signal attenuation in the horizontal polarized antenna is as high as 1,000 times (-30dBm) to the backside of the CPE than into the front direction. The vertical polarized antenna's attenuation to the back is 100 times (-20dBm) higher than into the front. This antenna pattern clearly shows the direction of the radiation density emitted by the antenna (here: front-side full density, back-side: almost none up to 1/1000 in H plane and 1/100 in V plane).

Given the fact that the air between your body and the antenna attenuates the signal as much as -25 to -30 dBm in a distance of a few centimeters already and the radiation characteristic adds -30 dBm to this, we have a 1,000,000 times weaker radiation density on the back. At max. EIRP of 1W for the CPE510 we are speaking of 0.000001 watts of energy sent to the back! With CPE210 it's even factor 10 weaker, so we are in the nano range.

If you are really concerned of 1 μW energy, I hope you never used a cell phone near to your ear and you also stay away far enough from microwave ovens, which can have up to 50,000 mW/m² (that's 50W/m²!) radiation density in the 2.4 GHz band caused by leakage, which is still being considered as mostly harmless!

What if i additionally mount the CPE510 onto a backboard out of steel (e.g. V2A)????

You would even have more attenuation, sure. You also could use aluminum coated wallpaper from your favorite DIY store (Baumarkt) in the attic or even in the rooms if this make you feel better (no joke, can make sense if you are sensitive to radiation).

...Please can someone help - also if you dont beliefe in radiation ;-)

If I would not believe in radiation, I wouldn't be in the WiFi business, but would raise and sell carrier pigeons instead. :D

Schreiben wir mal in deutsch weiter, ist zu umständlich, immer zu übersetzen.

sunshineh wrote

A)
Nethertheless i will make a backplate out of metal. But which material will cover the 5 GHz Radiation maximal? Which material shields best against 5 ghz??? (Steel , Alu , etc.)

Metall. Allerdings baust Du damit ein Reflektor und je nachdem, wie dieser wirkt, kann er Störungen bis hin zur kompletten Auslöschung des vom gegenüber liegenden AP gesendeten Signals bewirken. Weiter veränderst Du damit die Abstrahlcharakteristik des lokalen APs.

B)
And how thick should this material be?

Wenn Du eine Wellenlänge (~12,cm bei CPE210, ~6cm bei CPE510) dicke Platten nimmst, können die auch aus Beton sein, um das Signal komplett zu dämpfen. :D Ansonsten reicht schon Alufolie, wenigstens bis zum nächsten Sturm.

C)
And what about reflection of outsend energy? As you see on the picture with the sight to the red dot, you see in front a building with a red brick roof. Its very high so this will also reflect much of the power , your will it not? How strong does this radiation come back? I know its difficult , but please help.

Da Du das von Dir aus ansprichst: Was ist eigentlich mit den Kinderzimmern auf der Fläche, die Du beschallst? Ich will ja nicht mosern, aber Du machst Dir über die kaum noch messbare Reflektion des Signals von einem Gebäudes Gedanken? Also wenn ich den Floh von Strahlungsschäden durch WLAN-APs im Kopf hätte, würde ich mir zuerst Gedanken über die Strahlungsdichte des eigenen APs auf die Leute in dem Haus mit dem roten Dach machen und vielleicht doch besser 'ne Glasfaser rüberlegen oder - falls das nicht möglich - eine Standleitung bei der Telekom anmieten. Das musste jetzt mal raus.

Bei der ganzen Betrachtung übersiehst Du nämlich eines: die EM-Strahlungsleistung der Sonne beträgt bei klarem Himmel ca. 1.000 W/m². Und es sind diese Radiostrahlen, die Dich schwitzen lassen. Willst die Sonne auch in Alu einwickeln oder gehst doch lieber baden bei Affenhitze?

D)
The CPE510 does also have this "24V PoE" while normaly PoE is with 48V ...is there a adapter so that i can power my CPE510 over a PoE Switch (48V)????

Ubiquiti bietet Konverter von passive PoE auf "normales" PoE gemäß IEEE 802.3af an. Beides ist "normales" PoE, das eine halt standardisiert, das andere nicht. Schau mal auf deren Website nach PoE-Konvertern.

you could add another CPE to broadcast towards another direction (i.e. active switch in effect)