Hi

We have an area which we want to have non light of sight users in max 700m, what is the best wireless solution?
Do you think 900mhz is good?

Please help me to have this done.

what the blockage condition?
this is very important, let say it you non loS block due to very high mountain in between, then forgot about it...

you can use softwares for this reason. like online application at www.mywificoverage.com or Motorola PTP Link planner and etc.
they will give you approximate vision.

It's for city hotspot

What do you think for this
http://www.trangobroadband.com/wireless ... 00mhz.aspx

So, when you say city, you mean there are buildings in the way?

you can use softwares for this reason. like online application at http://www.mywificoverage.com or Motorola PTP Link planner and etc.
they will give you approximate vision.

I dont know how does it work, but i heared with SR9 we can have nlos network but i dont have any experince with that freq and i dont know what kind of cpe is need

Those software programs won't help with real life in a city. They contain no ground clutter data (ie if there is a great big sky scraper in the way), they also do not calculate inter-building reflections and refractions. 900MHz will go further through rough terrain, like trees, but all RF has major problems, regardless of frequency when there are huge great big buildings in the way!

Although, I used to bounce 10GHz microwave links via the side walls of buildings for temporary installs which we nicknamed 'dog legs'. If there was a building between us, blocking our line of sight, we would both fire our dishes at another common building we could both 'see' off to one side or the other. Not something I would recommend for permanent installs, but for us we only wanted the links for a few hours or a couple of days at the most. We also found we would sometimes have to rotate one dish back and forth as the reflected wave would sometimes get changed in polarisation.

On 2.4Ghz and 5.xx Ghz, LOS is requirement. It does not mean that links are not possible, but if they work, they are highly unreliable.

If you need non LOS links, use much lower frequencies. There is free band somewhere around 800-900 MHz, and Mikrotik supoorts such wlan cards.

Those software programs won't help with real life in a city. They contain no ground clutter data (ie if there is a great big sky scraper in the way), they also do not calculate inter-building reflections and refractions. 900MHz will go further through rough terrain, like trees, but all RF has major problems, regardless of frequency when there are huge great big buildings in the way!

Although, I used to bounce 10GHz microwave links via the side walls of buildings for temporary installs which we nicknamed 'dog legs'. If there was a building between us, blocking our line of sight, we would both fire our dishes at another common building we could both 'see' off to one side or the other. Not something I would recommend for permanent installs, but for us we only wanted the links for a few hours or a couple of days at the most. We also found we would sometimes have to rotate one dish back and forth as the reflected wave would sometimes get changed in polarisation.

Thanks for your reply but i didnt understand yor second pargraph, anyway rb433ah with sr9 with 15db sector antenna how far clients can be and how they can connect 900mhz means they can use their exusting samat phones or specual cpe need to have?

Thanks for your reply but i didnt understand yor second pargraph

If there is a building in your direct line of sight, you can reflect the signal off another building that the two ends can see. As long as the building you are bouncing it off, is reflective at the frequency you are using. You can only find that out by trying it as it depends on too many variable parameters to enable anyone to calculate if it was possible using just paper and pen. You have to actually try it and test it.

anyway rb433ah with sr9 with 15db sector antenna how far clients can be and how they can connect 900mhz means they can use their exusting samat phones or specual cpe need to have?

No idea, it depends on a number of variables, we have no idea what your terrain is like as you haven't told us, nor where you are located. What is a samat phone? What does "specual cpe need to have?" mean? Sorry.

Thanks for your reply but i didnt understand yor second pargraph

If there is a building in your direct line of sight, you can reflect the signal off another building that the two ends can see. As long as the building you are bouncing it off, is reflective at the frequency you are using. You can only find that out by trying it as it depends on too many variable parameters to enable anyone to calculate if it was possible using just paper and pen. You have to actually try it and test it.

anyway rb433ah with sr9 with 15db sector antenna how far clients can be and how they can connect 900mhz means they can use their exusting samat phones or specual cpe need to have?

No idea, it depends on a number of variables, we have no idea what your terrain is like as you haven't told us, nor where you are located. What is a samat phone? What does "specual cpe need to have?" mean? Sorry.

Sorry it is typing error, i mean smart phones, and second was special CPEs,
How they can connect to 900mhz AP?

Smart phones cannot connect to these point to point links. 900MHz is meant for backhaul links, not for the 'last mile' where it connects directly to clients. If you need to connect to end users, you are really just stuck with using 2.4GHz.

900MHz is meant for backhaul links, not for the 'last mile' where it connects directly to clients. If you need to connect to end users, you are really just stuck with using 2.4GHz.

Did you mean to say something different? I would say a large number of wISPs would disagree, you know, like all those that are running 900Mhz canopy, ub, etc gear.

Was this comment specifically for the 'smart phone' application, because that makes sense, otherwise .....

I meant for connection directly to mobile clients, as you suggest, like mobile phones. Of course, it is always possible to use 900MHz for a point to point fixed link, whether it is a backhaul or a client. From the original posting I got the idea he wants to connect to many users over a large area (he mentioned a 'city hotspot') and I wanted to make it clear that even if the mobile phone supports the RF frequency band of approximately 900MHz, this technology is not the same as that used inside a phone. Therefore, really, for support to mobile phones via a 'hotspot' the only viable option is via 2.4GHz Wifi.

Sure, that makes perfect sense.

A large area 'hot spot' and 2.4Ghz phones is a significant project. 2.4Ghz is effectively the only possible solution and with small handsets (low gain ant, ~2-3dBm) one would require either a VERY large number of APs or a large number of APs with high gain antennas. High gain antennas will increase noise reception, probably past an acceptable SNR, so many APs is the likely solution. Also, WDS and DHCP repeaters with a single, central DHCP server so clients can roam.

This would actually be a pretty interesting case study on HWMP+ meshing. Clients are probably very likely to be talking to other clients so the mesh topology would provide redundancy for failed APs and shortest-hop calls. OSPF would be another likely solution of course.

Virtual APs would also be optimal, to separate VoIP from Laptop data so VoIP can be distinctly secured and QoS rules applied to the vAP interfaces.

OP: Are you thinking stand along wifi phones are a SIP client on a smartphone?

What is the topography? 700m long, square, odd shape? 2.4Ghz will handle some NLOS at short distances and through walls to a certain degree, or are you thinking through trees?

I guess it would be prudent for you to define NLOS in your case. Buildings, trees, hills, walls, etc.