I just bought a vacation condo in Costa Rica, and will maybe spend 6 weeks a year down there. Inclding friends and friends of friends, we have about 12 units among us. We're thinking about having one condo have fast internet access and everyone else connect to him through wireless. Using a LinkSys WRT54G, and accessing with my Snoy VIAO, I can go one floor above, below, and across the hall and get a pretty good signal. Two floors away and it gets iffy. The complex consists of 8 6-story buildings in a circle each separated by about 100 feet. All of the condos in question have line-of-sight or are in the same building as the "master condo".
After a couple days perusal on the web, I've discerned (perhaps incorrectly):
1) 802.11a has less interference with phones, microwaves, etc so perhaps should be considered
2) I can spend $1000 for an "access point", which is different (better?) that a wireless router
3) I can buy antennas to attach to wireless routers to increase the range to over 500 meters
4) I can attach antennas to the receiving end as well
I'm headed back down to Costa Rica in April, and I hope to bring all the equipment I need with me to set this up. Any advice you guys can give me will be greatly appreciated. I think now I'm leaning towards Netgear 802.11g routers with antennas on both ends, but that's based on admittedly not enough information.
When everyone is there at the same time you'll notice some congestion, but this ought to be do-able.
What's the construction of these buildings? Concrete & rebar, wood & drywall?
802.11a doesn't go thru walls at all, it's really meant for office environments (conference rooms) where you don't want coverage outside the room.
Or you can spend $50 for an AP. Dunno what you'd get in a $1K AP that would make it 20X as good as a $50 AP...
Extra antennas will cost as much as an additional AP, though they can have some uses.
I'd go with a single Linksys BEFSR41 router and a number of Linksys WAP54G APs in some mix of multiple-APs, repeaters, and clients depending on the details of the layout, available computers, and other such, but that's because I have a lot of experience with Linksys hardware and I'm pretty happy with it.
It kinda depends on what your requirements are, and how technical (and/or demanding) your users are going to be, and how isolated from each other they want/need to be. What's the ISP, and what do they charge monthly for broadband? You might want to have more than one broadband link, and more than one co-op group...
I'd advise using the Buffalo High Power Ethernet converters ("
formatting link
") on each computer, and a Buffalo high power router ("
formatting link
") in the condo unit with the internet access.
Three reasons:
First, it makes a big difference in signal strength because of the higher power. I can attest to this personally. In my city they just began offering free wireless, and the access point is on a pole about
100' away. With the a regular 802.11g card or adapter, I got a "very low" or "low" signal, with the high power card I get a "very good" or "excellent" signal. So I hooked the high-power Ethernet converter to my Netgear wireless router (different channels) and I get free wireless for the whole house, with the machines inside the house only needing the less expensive non-high-power components.
Second, it has an external antenna jack, just in case you want to use a better antenna (though be sure to use the shortest antenna cable possible--the signal strength gain from antennas is often very marginal because of the losses in the cable from the router or adapter to the antenna)
Third, because the adapter connects via Ethernet, you can run a long cable from the computer to the Ethernet converter so you can place it for best reception (or you can place just the converter for best reception, and then create a wireless network in the condo using cheaper non-high power 802.11g components). Similarly, you can run a long Ethernet cable from the cable modem or DSL modem to the high power router, so you can position the router for optimal signal. This router also can be used as an access point, so you could buy several of them if needed, and connect them all to the router.
I wouldn't advise buying the Buffalo high power CardBus card for notebooks. Even though it has an antenna jack, there are big losses in attaching a long antenna cable to the card, and it could be inconvenient to have to position the notebook for best signal strength.
There are some other vendors of high power equipment
I'm kind of drunk tonight but you can do this easily. I can make you an access point to aim at the building that will work fine. I will reply to you later. I have replied on this group before they bash you a lot.
I'm kind of drunk tonight but you can do this easily. I can make you an access point to aim at the building that will work fine. I will reply to you later. I have replied on this group before they bash you a lot.
I'm kind of drunk tonight but you can do this easily. I can make you an access point to aim at the building that will work fine. I will reply to you later. I have replied on this group before they bash you a lot.
I'm will get intouch with you, it can be done easily. I can make you an access point to aim at the building that will work fine. I will reply to you later. I have replied on this group before they bash you a lot.
The rule of thumb is 1 wall is no problem. 2 walls is iffy. 3 walls won't work. If the walls are made of concrete or have aluminium foil backed insulation inside, nothing will work. In general, it's a bad idea to try and go through walls. Windows are easy. Glass is quite transparent to 2.4GHz RF. However, if you have some type of metalized mylar coating on the windows, RF will not penetrate.
Can all the condos in the circle see a single point where a high speed connection can be located? If so, you have literally an idea arrangement. Just place a central access point at the center of the circle and you have uniform coverage of all the condos.
Any trees in the way? What are the construction materials in the condos? If wood, 2.4Ghz will go through. If concrete, you'll have to go through the windows.
Equipment is more expensive for 5.7GHz. Interference is less, but there are a substantial number of outdoor 5.7GHz links that might cause problems. However, Costa Rica is probably not as congested as US cities.
A "wireless router" is nothing more than an "access point" with an ethernet router attached (in the same box). Almost any "wireless router" can be used as an access point by simply ignoring the router section. Instructions have been posted many times.
You'll probably need a wireless router because your broadband connection will probably be limited to a single IP address. In order to share the connection with multiple computers, you'll need NAT (network address translation) which requires a router. On the other foot, if your broadband ISP supplies multiple IP addresses, then you can use an access point (no router) and let each user have a routeable IP address.
Antennas are not a free lunch. Since you're apparently using a single wireless access point and the condos are arranged in a circle, an omnidirectional antenna is appropriate. The problem is that as the antenna gain on the omni antenna increases, the vertical radiation angle decreases. An 8dBi omni (at 2.4Ghz) has a vertical radiation angle of about 15 degrees. A 12dBi omni is about 7 degrees (or less). If you have ANY vertical elevation differences between the central antenna and the client radios, you'll have a problem. Is the terrain flat?
Let's do the trigonometry. 100ft range and a 3.5degree vertical elevation is: vert = 100ft * tan(3.5deg) (for an 12dBi omni) vert = 6.1ft or vert = 100ft * tan(7.5deg) (for an 8dBi omni) vert = 13.2ft If you have a +/- 6ft or 13ft vertical difference between users and the horizontal elevation of the antenna, the signal will suffer severely. It's even more narrow at 5.6GHz. This is one reason why many such systems use panel antennas instead of omni antennas.
I suggest you run your calculations and initial testing with a decent
8dBi 2.4GHz omnidirectional antenna to cover the easy users, and than add a 2nd access point and a more directional antenna to cover the holes and hardship cases (the ones that wanna go through walls).
Huh? All antennas are both transmit and receive. I think you mean attaching one at the client radio (CPE or Customer Premisis Equipment). An external antenna at the client end will be a huge help in getting enough signal for a reliable connection. Some type of panel antenna placed in the window would be ideal. Simple reflectors such as:
formatting link
a big help. There are also client radios that have integrated panel and patch antennas (typically with about 8dBi gain).
Well, for the system you describe, almost any wireless router and any client radios will work. 100ft range is well within the capabilities of commodity wireless hardware. I would suggest you do something a bit different. Stay on 2.4GHz (because it's cheaper). Buy a mixture of wireless 802.11g hardware and antennas. Two wireless routers, multiple brands and models of clients, a few different antennas, reflectors or even home made antennas. Drag it all to Costa Rica in April and see how it plays. Some things will work well, others may not. Lots depend on the location, topology, construction, and environment. When you have a combination that works, order some more and have it shipped to Costa Rica. I'm not too sure this is such a great idea but at 2AM, it's the best I can do.
Also, I wouldn't expect too much in the way of hackers, Netstumblers, and wireless DoS attackes in Costa Rica. Therefore, a fancy intrusion detection and security system isn't really necessary. However, to keep the other tourists with laptops out, you should be sure that your system supports WPA encryption. If you plan to make this a hotspot system similar to a hotel wireless system, you may need a specialized wireless router with a built in authorization and authentication system. In any case, think about how you would handle abusers (i.e. file sharing, BitTorrent, bandwidth hogs, hackers) and control access.
" These are marketed as two separate products, but in reality they are the same product, just with some labeling and firmware changes, and the omission of the WAN connection on the Ethernet Converter. So I guess they are allowed to share an FCC report.
Yeah, and let's see the receiver sensitivity and datarate/capture specs for the other direction.
If you need 10dB of fade margin to work thru multipath, I'm not seeing high power as much of a solution (except in point-to-point links when properly engineered). Isn't ERP still limited to 1W?
And then of course, in addition to the "alligator" problem, there's the escalating power wars to come.
I see a significant difference, versus other external devices I've used.
I have no connection to Buffalo Technology. They used to have good tech support, based in the U.S., but last time I tried to call, I was on hold for about an hour, and then gave up. Just as well for me to have figured out the problem on my own I guess, but maybe the reason there were so many returned units at Fry's was that too many people gave up on getting the configuration right and couldn't get any tech support.
'FDI-09101577-0'Curses. No internal photos because it's just a change order, not the original type certification. Digging... FDI-04600264-0 |
formatting link
'FDI-04600264-0'The original listed power on this version was 80mw (+19dBm). I guess they cranked up the power on the current unit.
+25dBm tx power. That's a substantial increase over the usual +17dBm. By itself, that will be approximately a 2.5 times increase in range. and a 6.3 times increase in coverage area (assuming an omni antenna with circular coverage area). If everyone purchased one of those, the average access point density (AP's per square mile), that would work without interference, would be about 1/6th. For every one of these high power routers, we lose the ability to use 5 additional low power access points. (Number juggling is so much fun).
+22dBm xmit for 802.11g. +20dBm for 802.11b.
Thanks all for all of the (overwhelming) information. Seems to me like there are two viable paths:
1) put Pre-N MIMO routers everywhere
2) Use non MIMO routers with external antennas.
Seems like putting an external antenna on a MIMO router would be nonsensical. USRobotics claims that MIMO is mostly hype and that their rangeMax router is nearly as good as MIMO. Which implies that it would be way better than MIMO once I put on an external antenna. So that's what I'm leaning towards. I like Jeff's idea of trying a couple different brands, as one may work better than another simply due to the environment. The walls are all concrete (everything is concrete in Costa Rica), but we have good line-of-sight between the buildings. I'm hoping that the guy on the 1st floor in the same building as the guy on the 5th can get it from across the way rather than straight down through all that cement.
So unless someone strongly objects, my plan is to bring down with me: USR G router and antenna Netgear G router and antenna LinkSys G router and antenna
And see what's what. Maybe buffalo is the right solution, but I've never heard of them so I'm a little leery. I've had good experiences with the brands I know. Except now that I think about it, my wireless linksys router needs to get rebooted periodically. If I restart my computer which attaches to the linksys WRT54G enough times, eventually it disappears and I have to walk over, unplug it and plug it back in, and then it works fine. Anyone hear of that?
Many thanks again for all your help. I'll let you know how it turns out!
I'm in NYC now, at the Buffalo card is saving me $10 per day, as I can pick up two free hotspots from my 9th floor hotel room. With the internal wireless I can't get any free hotspots.
Just thought I'd post a quick followup: I bought a Hawking 15db corner antenna, unscrewed both the standard antennae on my WRT54G, screwed in the Hawking, and tested the range. I tried a bunch of different orientations, and at best it was as good as the original antenna. Maybe I could get it to work a little better with some finagling, but it was very disappointing. I returned it to Fry's and purchased instead a MIMO Netgear WPN824 (on sale for $99). I'm still having issues getting it configured (simply due to personal incompetence), but it is WAY WAY better that the Hawking external antenna. I guess WAY WAY isn't very scientific, but I took it outside and walked about 300 feet away and still was able to access the internet. So that's my new solution. Just bring this router down to Costa Rica and test out the connection. Apologies to the guy who suggested that in the first place. Next time I'll take you seriously!
Cabling-Design.com Forums website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.