network problem

[yiannis]

Hello i have set a network in a small islant of Greece my problem is idont have lot of speed. My house is 4 kilometers from the village (ADSL connection) is behind a small hill so I put a ns2 at station mode to the village with a grid antenna 26 dbi. and at the top of the hill a ns2 with a same antenna the distance is about 3.5 kilometers at access point mode . At my house at the bottom of the hill 300 meters from the top of the hill I put a ns2 at station mode with a grid antenna 24 dbi but is faced the back side of the hill antenna. I have connection but not very fast and not stable some times is 9 mbps some times 70 kbps maximum 12 mbps between the village and the hill.at the village station the Signal Strength: is -43dbm and the transmit ccq is normally between 80 % to 100% the TX rate is sown 54 mbps and the rx rate 48 mbps
But when I make the network speed test the speed is RX 6.41 Mbps TX 798.68 kbps and this change all the time but never higher than 9 mbps and some time I loose internet connection .at my house station the Signal Strength: is-78 dbm and the TX rate is normally 36 mbps and rx rate about the same and the transmit ccq about 64 % to30% some times But when I make the network speed test the speed is RX 7.50Mbps TX 4.80 mbps and changing is it normal these speeds because I can not see a small video from you tube without stop it several times can somebody tell what adjustments I must do to have better speed if I will change channel iam at 12 now will make the thinks better

[LordTalcor]

Don't know if this is what you need or not, but Wifi442 spanned a 15mile link over a hill/mountain with this setup

http://forum.ubnt.com/forum/viewtopic.php?t=7256

[WHT]

As it is, you have a 47 dfB fade margin from the village dSL point to the top of the hill..MORE than you'll ever want. Try setting the radios down to like 22 dBm output and see what happens.

Try it without the grid antennas. Using the stock internal 10 dBi antennas will get you a good 20 dB fade margin, BTW.

[LordTalcor]

WHT,

Can you explain db to me in simple terms? When I do a scan of a wifi spot, the db's come back as -72 or -91, -54 etc

What signal am I looking for? Lower number or higher?

[MaximumISP]

With integers The lower the better
ie -72 is better than -90

[yiannis]

As it is, you have a 47 dfB fade margin from the village dSL point to the top of the hill..MORE than you'll ever want. Try setting the radios down to like 22 dBm output and see what happens.

Try it without the grid antennas. Using the stock internal 10 dBi antennas will get you a good 20 dB fade margin, BTW.what do you mean if iset the radio lower the speed will go up ?

[WHT]

Can you explain db to me in simple terms?
There is a lot of interaction nuances. Generally you would think that increasing the power is necessary for faster speeds, but there is a point where too much power overdrives the receiver's front end and performance suffers (lower experienced speeds).

Rules of thumb....

Numbering syntax (syntax is not a tax on cigarettes and beer):
* -90 dBm receiver sensitivity is more sensitive than -70.
* -90 dBm is a less powerful signal than -70 dBm, i.e -90 dBm is a weak signal and -70 is a strong signal.
* Receiver sensitivity decreases at higher speeds. Therefore at 6 Mbps, the receiver sensitivity may be -90 dBm, but for 54 Mbps it may be -70 dBm. That means you need a stronger signal.
* Generally more than -20 dBm received signal level overdrives the receiver's front end. Reduce your transmitter power form say, 26 dBm down to 20 dBm (that means you reduced it down to one-fourth). That is all right in point to point applications liek you have, but foe point to multipoint, its better to mis-align the clent antenna to reduce the siganal it is receiving.

[LordTalcor]

Thank you guys for the explanation. That clears it up a bit for me :D

[yiannis]

hello please help mine the Signal Strength: is-44 dbm and the speed at speed test is 11mbps how i can have more speed?

[yiannis]

Can you explain db to me in simple terms?
There is a lot of interaction nuances. Generally you would think that increasing the power is necessary for faster speeds, but there is a point where too much power overdrives the receiver's front end and performance suffers (lower experienced speeds).

Rules of thumb....

Numbering syntax (syntax is not a tax on cigarettes and beer):
* -90 dBm receiver sensitivity is more sensitive than -70.
* -90 dBm is a less powerful signal than -70 dBm, i.e -90 dBm is a weak signal and -70 is a strong signal.
* Receiver sensitivity decreases at higher speeds. Therefore at 6 Mbps, the receiver sensitivity may be -90 dBm, but for 54 Mbps it may be -70 dBm. That means you need a stronger signal.
* Generally more than -20 dBm received signal level overdrives the receiver's front end. Reduce your transmitter power form say, 26 dBm down to 20 dBm (that means you reduced it down to one-fourth). That is all right in point to point applications liek you have, but foe point to multipoint, its better to mis-align the clent antenna to reduce the siganal it is receiving.hello please help mine the Signal Strength: is-44 dbm and the speed at speed test is 11mbps how i can have more speed?

[Albinchik13]

Can you explain db to me in simple terms?
There is a lot of interaction nuances. Generally you would think that increasing the power is necessary for faster speeds, but there is a point where too much power overdrives the receiver's front end and performance suffers (lower experienced speeds).

Rules of thumb....

Numbering syntax (syntax is not a tax on cigarettes and beer):
* -90 dBm receiver sensitivity is more sensitive than -70.
* -90 dBm is a less powerful signal than -70 dBm, i.e -90 dBm is a weak signal and -70 is a strong signal.
* Receiver sensitivity decreases at higher speeds. Therefore at 6 Mbps, the receiver sensitivity may be -90 dBm, but for 54 Mbps it may be -70 dBm. That means you need a stronger signal.
* Generally more than -20 dBm received signal level overdrives the receiver's front end. Reduce your transmitter power form say, 26 dBm down to 20 dBm (that means you reduced it down to one-fourth). That is all right in point to point applications liek you have, but foe point to multipoint, its better to mis-align the clent antenna to reduce the siganal it is receiving.

Thanks very much))) :D

[WHT]

hello please help mine the Signal Strength: is-44 dbm and the speed at speed test is 11mbps how i can have more speed?-44 dBm is a good number, not too much as to overload the receivers' front ends and not too little to meet the minimum receiver threshold for 22 Mbps throughput (11 Mbps on an internet sped test - not the internal NS speed test).

But just to make sure...have you taken off the high gain antennas yet to test? If not, can you simply mis-align them a tad bit and see if that improves anything?