LS71, SR71A and parabolic dish 32dbi 4 feet mimo 2x2

[kissas]

using this, its possible to get more than 60 mb in a 50 km distance?

best regards.

[WHT]

You mean 60 Mega-bit over the air data speed or FTP speed?

[kissas]

ftp speed, or what hardware can archive that speed.

[WHT]

60 Mbps FTP speed means you'll need at least 120 Mbps data speed. Do you have any idea how much signal you'll have to deliver at the end of 50 KM with sufficient fade margin to achieve that???

[Shockware1]

You might want to do 2 links of 25 miles if possible.

Edit, 25 KM if possible.

[kissas]

60 Mbps FTP speed means you'll need at least 120 Mbps data speed. Do you have any idea how much signal you'll have to deliver at the end of 50 KM with sufficient fade margin to achieve that???

no, for that reason i'm asking to the people that have more knowledge about this.

i'asked to the person who need this, and the distance its 25 km
what need to use and what are the maximun ftp speed that i'can get, i'need at least 80 mbps.

i'm testing the LiteStation-SR71 with SR71-A using mimo 2x2 in the lab and i'm getting 20mbps transfer speed with iperf. i'need more, any advice?
best regards.

[kissas]

You might want to do 2 links of 25 miles if possible.

Edit, 25 KM if possible.

you can share what equipment need to have a 25 km link with at least 80 mbps?

its LiteStation-SR71 with SR71-A enough to do the job?
thx

[Shockware1]

on paper that speed should be more easily obtained at 25KM than at 50KM. I don't have any personal experience with a setup like that however.

Dual chain N has an over air rate of 300mbps, so 80 should be a breeze if all other factors line up. You will need 40 mhz of clean spectrum, great LOS, dual polarity dishes of sufficient size, and some luck I bet.

Once again, never done it. It is possible that even 25KM is too far to get those speeds...

[kissas]

i'undertand you, but why in the lab i'm getting only 20mbps :S that its what i dont understand.

[Shockware1]

You need to explain how you are testing and how you are measuring. There are several things you could be doing wrong to get bad results in the lab.

For example, if you are testing the units 2 feet apart you are probably overloading the front end of the radios, causing degraded performance. Your ACK timeout is probably set to a very inefficient value...

Also, at that distance you probably have issues with polarity isolation. You do need to hook up 2 antennas to test as well... So you do need to explain your test environment.

[kissas]

Shockware1 thanks for taking time to answer , i'm testing with only the feed horn's and the sr71 in a table, the feed horn are less than 50 cm each , i'm planning to do a street test, what are the minimun the distance can be done the test? 200 meters?

[Shockware1]

You must have a maximum of -50 signal, but -55 would probably be better. If you have large dishes you will have to get a lot of distance between them. Also, you will have to be sure that the polarity for each chain is proper. You will probably have to assemble the dishes to achieve this.

You do have dual polarity dishes yes? If not you will have to use 2 separate dishes to do this test properly. Each dish should be on a different polarity in order to get better isolation of each N chain.

[kissas]

i'tested again in this way:
using 3x3 mimo, brass wires 4 cm long (3 db each ) on each N female connector, one litestation is less than 2 meter of the other.
one in station and the another in access point, two laptop , one on every litestation through the ethernet port, running iperf in this mode:
server iperf.exe -s ( server mode )
and the client


iperf.exe -c 192.168.1.23 -P 1 -i 1 -p 5001 -w 56.0K -l 2.0M -C -f m -t 10


and the result is :


Client connecting to 192.168.1.23, TCP port 5001
TCP window size: 0.05 MByte
------------------------------------------------------------
[1912] local 192.168.1.200 port 2951 connected with 192.168.1.23 port 5001
[ ID] Interval Transfer Bandwidth
[1912] 0.0- 1.0 sec 12.0 MBytes 101 Mbits/sec
[1912] 1.0- 2.0 sec 10.0 MBytes 83.9 Mbits/sec
[1912] 2.0- 3.0 sec 12.0 MBytes 101 Mbits/sec
[1912] 3.0- 4.0 sec 10.0 MBytes 83.9 Mbits/sec
[1912] 4.0- 5.0 sec 12.0 MBytes 101 Mbits/sec
[1912] 5.0- 6.0 sec 10.0 MBytes 83.9 Mbits/sec
[1912] 6.0- 7.0 sec 12.0 MBytes 101 Mbits/sec
[1912] 7.0- 8.0 sec 10.0 MBytes 83.9 Mbits/sec
[1912] 8.0- 9.0 sec 12.0 MBytes 101 Mbits/sec
[1912] 9.0-10.0 sec 12.0 MBytes 101 Mbits/sec
[1912] 0.0-10.3 sec 114 MBytes 92.5 Mbits/sec
Done.


channel : 157 11 Na 40MHz
in the main page of the station i see this Signal Strength: -39 dBm
the Output Power is 11dbm in both and the Distance under advanced tab is the same if have 0 or 27.4 km not change in the result changing the value.

this its accurate?

best regards.