Advice needed from 6km nLOS

[tokcok]

Hi guys,

I am from malaysia and this is my first time here on this forum.

I would like to receive internet from my friends house as my area only have dial up. According to google earth, we are about 6km far apart. But from my friends house, i cannot see my house. So to be safe, i think there is no clear Line of Sight. There are no hills or mountains in between.

How can i link it up? Latency is one big problem. As some of you know, the internet here is really crap, only 1mbps ADSL and 300ms ping to yahoo.com, i cannot afford to lose any more latency.

Pls advise what kind of products is needed. I guess i have to import it. And i only have 1 try - if cannot work, i got no more budget. There is no local installations,providers for such things.

My budget is around 2k usd.

Thanks!!

[Alan87i]

If possible try to find a ham operator or someone with radio experince to survey the area for RF signals in the 900 Mhz band. 900 mhz to 920 mhz.
If there's low noise and no transmitters in use a pair of 900Mhz AP's matched with 13 Dbi yagi antennas might do the job for you .

[DohDoh]

How is that possible if at 1.5 miles, friend's house NLOS, a 24dbi grid antenna will not work according to what people told me.

:confused:

[Alan87i]

2.4 Ghz might work if he can get them up high enough. tokcok explained he has enough $ for 1 try . If there is not enough ground clearance, Fresnel zone area along the link it will suffer High retries and errors on both TX and RX. I know I have that exact set up at just over 7 Km's both are on 65 foot tv towers. I have a Clear line of sight but 1 small hill in the middle of the link is causing 20 to 40 % retries. Using 400mw on 2.4 Ghz with 24dbi grid antennas.
That's a gamble I don't think tokcok wants to take. Even 900 Mhz is a gamble because of interference or noise issues. Most radio scanners will work on that spectrum and give a % of help in figuring out if there's a system of sorts running on the 900-920 band.

[ad5mb]

How is that possible if at 1.5 miles, friend's house NLOS, a 24dbi grid antenna will not work according to what people told me.


There is the possibility that your friends don't know what they are talking about. Lot of that going around.

RF path loss and Signal Operating Margin calculator (http://www.terabeam.com/support/calculations/som.php)

[DohDoh]

There is the possibility that your friends don't know what they are talking about. Lot of that going around.

RF path loss and Signal Operating Margin calculator (http://www.terabeam.com/support/calculations/som.php)

Am I the receiver or the transmitter?

Check out my thread:

http://forums.wi-fiplanet.com/showthread.php?p=37658#post37658

[ad5mb]

Am I the receiver or the transmitter?

Yes.

The radio in your system is a transceiver, a receiver and a transmitter. You are both.

Standard issue consumer grade transmitters put out 15 dBm. If you are using off the shelf consumer grade equipment on both ends, the formula is probably good for both ends.

The end that has the Internet should be used as the transmitte, the end that gets the internet should be the receiver.

If one end has more power than the other end, the less powerful end may be able to hear, but unable to reply. Calculate with the roles reversed if power is not the same on both ends.