240Km link with RB532 @ 20Mbits

RouterOS Wireless Networking
1

Kemal from cyprus.com has completed his 240Km link to Lebanon. More information:


Thanks!!!

We established a 244km p2p 5ghz link!!! Thanks for this product

Signal is -65 and rock solid!!!

We are at Cyprus. both sides at more than 800 meters above the sea level.

We used 1.2 meters dish sr2 for 2.4Ghz : signal is -67 and stable… we have more than 10 days link uptime. We used RB532.

With Nstream enabled we had approx. 20mbits oneway. I believe with pc it will be much and much more…

Pings : minimum : 8ms, Max : 21ms

Ill send you 5ghz result after this week.

2

I was skeptical, so i took a deeper look:

Nr1) SR2 = tx power 400mW

Nr2) RX sensitivity at band 36Mbps (topic said that it was 20Mbps link so the air-rate should be 36Mbps at least) for SR2 = -83

Nr3) 1.2 meters dish - if i’m not mistaken it is about 35dBi

Nr4) there must at least half meter of cable between antenna and RB532

Nr5) there are no big difference in frequency settings we can choose any - 2412 MHz

I tried several link calculators including this:
http://www.mikrotik.com/test_link.php

My results:
it is theoretically possible to have signal level of - 47 at 130km
it is theoretically possible to have signal level of - 48 at 145km
it is theoretically possible to have signal level of - 49 at 160Km

so, -65 at 244Km, hmmm

3

Some questions -

could you inform us about CCQ of the link and ping time???

4

Highest transmitted frequency : 5810.000 MHz (5.810 GHz)
Wavelength : 2.031 inches (5.160 centimeters)
Transmitter RF power output : 26.000 dBm (398.107 milliwatts)




Transmit cable type : Times Microwave LMR-600
Transmit cable length : 1.640 feet (0.500 meters)
Total transmit cable loss : 0.119 dB (0.073 dB/foot 0.238 dB/meter)
Total transmit connector loss : 0.500 dB through 2 connectors
Total transmit cable loss : 0.619 dB
Transmit miscellaneous losses : 1.000 dB

Transmit antenna peak gain : 35 dBi
RF input power to the antenna : 25.381 dBm (345.223 milliwatts)
Allowed input power to antenna : 20.333 dBm (107.969 milliwatts) Per FCC Part 15 rules
Transmit antenna height : 2624.672 feet (800.000 meters)
Distance to the radio horizon : 70.300 miles (113.137 kilometers)




Receive cable type : Times Microwave LMR-400
Receive cable length : 1.640 feet (0.500 meters)
Total receive cable loss : 0.178 dB (0.108 dB/foot 0.355 dB/meter)
Total receive connector loss : 0.500 dB through 2 connectors
Total receive cable loss : 0.678 dB
Receive miscellaneous losses : 1.000 dB

Receive antenna peak gain : 35 dBi
Receive antenna height : 2624.672 feet (800.000 meters)
Distance to the radio horizon : 70.300 miles (113.137 kilometers)



Received power level : -61.778 dBm (182.211 µV)
Receiver’s threshold : -82.000 dBm (17.762 µV)
Thermal fade margin : 20.222 dB Very good link.
Probability of outage : 0.1 %
Total free space path loss : 155.481 dBi over a path length of 151.615 miles (244.000 kilometers)
Peak transmitted EIRP : 59.381 dBm (867124.763 mW) This power output violates current FCC rules for point to multipoint links.



Midpoint 0.6 Fresnel zone boundary : 142.539 feet (43.446 meters)
Maximum space wave communications distance : 140.600 miles (226.274 kilometers)

5

From my calculation above it is very possible.

His result of -65 shows an additional loss of 4 dBi over my calculation of -61.

His Heights are what make all the difference.
800 meters is very high, and over water would indicate very little interference sources.

Congrats Kemal !!!

6

What about your ack-timeout?
Are you able to made the link without nstreme (nstreme bypass the ack-timeout limitation that, if I’m not in wrong, is of 409us for Atheros 5213)?

7

DAAAAMN GOOOD WORK :slight_smile:.

8

congratulations…

hmm - sorry for the maybe stupid question, but are you really allowed to do such a high output power in your country??

I´m only allowed to do 1000mw (30db) her - so no possibility to do such a link :laughing:

9
10

to mipland: link is NOT possible without nstreme as it was continously connecting/disconnecting due to ack problem.

to matthias: we have rules here that allows us 2W eirp for p2mp links but they dont cover p2p links. We are trying to explain to prehistoric minds in our government that we are in export business now but they are having hard time understanding how we can export something that you cant touch.

macgiver: below is average ping times when there was approx 2mbits passing through the link.

100 packets transmitted, 100 packets received, 0% packet loss
round-trip min/avg/max = 5/10.2/35 ms

with this traffic TX/RX CCQ is almost always at 100/100

I must say that we were very skeptical of any link of this magnitude as well, but guess what, it works!

anyone in egypt want to shoot for a 500km link? naah :laughing:

Kemal

11

Thanks Kemal, this

is very important for me. I had the same issues with a 112km link: succesfully connection for about 1-2 seconds, then disconnect, then succesfully connection for 1-2 sec. then disconnect and so on… and your answer is the confirms my doubt!
Thanks again

12

Excellent Work!

Lebanon and Cyprus, both Small but effective countries. I feel proud.
Thank You Mikrotik.

Cheers.

13

Excellent.

What are its country’s EIRP Limitations without licence ?

14

please post a radio mobile archive with the network so that we can drool over the pretty pictures :slight_smile:

15

it was in the other topic i think

16

Where exactly in Lebanon? How far inland? Shouldn’t be far coz Mountains go straight into the sea in most Lebanon.

17

GOOD JOB ,

i think we must try a link to TRIPOLI : ) in lebanon i have a hight point here i use it as HOTSPOT point to cover all North Lebanon Plan,


Maybe we will try to communicate .

18

what is the thoughput you are getting on this link in terms of MB? I suggest if possible,try putting up an FTP server one side and ftp cleint on other side and transfer so big file so that you get the actual stats of througput

19

Good work thanks for the work can u please past your configuration and the names for the equipment that you use?

20

Can you do some pictures of the setup?

Are the feeders you used hand made?

I am interested in general to see how people there in Cyprus do their stuff.

Here are some pics from various more or less important nodes of our network.

http://info.awmn.net/users/cpg/index.php?cat=2&page=1
Here is one we did a while ago… not as long but very critical as it bonds 2 distant and remote places around athens … I believe that we had loads of other attempts and successes from other people in our community..
http://info.awmn.net/users/cpg/thumbnails.php?album=140
http://wind.awmn.net/?page=nodes&node=6041&session_lang=english

Has anybody of you tried setting up solar panels, wind generators or something similar to power those boards in remote places? we are looking into it since this is our main problem for links like these…power..

Lots more are to come given the weather and the timing is good :smiley: