Correct Place for 802.11 Questions?

[bluewhaleCA]

Hi. I'm just getting into wireless ( 802.11b for now ). I have somewhat specific questions about extending a new installation, Antennae configuration and patterns, focused ( ieringle can ) antennae's ( Yaggi? ), etc.
Is this the proper forum within Tek-Tips for these questions?

Thanks

Paul

 

[edfair]

ask away Ed Fair
unixstuff@juno.com
Any advice I give is my best judgement based on my interpretation of the facts you supply. Help increase my knowledge by providing some feedback, good or bad, on any advice I have given.

 

[bluewhaleCA]

Thanks Ed, I'll try to be brief. If not actually make sense.

I installed a Linksys BEFW11S4, a Linksys PCI WiFi NIC and a Linksys PC Card WiFi NIC. The router is in a heating closet near one end of the house, accessible only from the outside. The primary target for it is at the other end of the house. With the router in that closet I can get perhaps 75% signal strength when in the bedrooms near it, say within 30-40 feet and through 1 or two walls. I tried moving the router into the hallway ( without the Cable Modem connection: just measuring signal strength ). The PC Card NIC was getting 80% signal strength at about 50' down the hall, direct line of sight with the router. No signal was available in the family room at any time. Distance between the closet and the family room is about 120', through perhaps 4 interior walls.

Linksys sells the WAP11 to act as a bridge, however that requires a CAT5 patch cable. Wiring here is a last option per the owner. I plan on going back to try the other channels available however really doubt that a different channel will more than double the distance we currently can use. I've read a number of articles on line about this and wonder :

1: Would a focused, directional antennae, like the 'pringle can' units help? Specifically would it help to punch through the interior walls which are (??) adding to the problem?

2: I have found 1 Watt and half Watt amplifiers for the router. Would they be likely to resolve the signal strength problem? IF so, for what reasons should I avoid using them? ( legality in US, health problems caused by power of units, etc )

3: I would prefer to keep power low and have repeaters for security reasons. Might you know of a way to do this without running a patch cable from the router to the bridging unit?


Thanks for any thoughts you might have!

Paul

 

[edfair]

These are question for others. But you may want to look through the other threads here where people have used directional for miles. Ed Fair
unixstuff@juno.com
Any advice I give is my best judgement based on my interpretation of the facts you supply. Help increase my knowledge by providing some feedback, good or bad, on any advice I have given.

 

[daronwilson]

Good Questions indeed.

1: Would a focused, directional antennae, like the 'pringle can' units help? Specifically would it help to punch through the interior walls which are (??) adding to the problem?

Indeed focusing the signal would help, IMHO the pringles can is a less than reliable device. First, lets imagine the stock antenna and the pattern it exhibits. If you were to draw a magical doughnut around the antenna, you have an idea of what the pattern looks like. This one would be a tall fluffy doughnut, with much of the signal going up. Now if you were to replace that antenna with a higher gain omni directional antenna, that doughnut would get squished out almost flat. The signal would extend horizontally very well, not up hardly at all. For example, if you were to put a 12dB antenna there, you would find a narrow vertical window (5-10 degrees) of signal. Keeping in mind the jump for 2db to 12 db would give you 10dB more signal or roughly 4 times the signal strength.

Now, lets try and make that signal go where you want it. A flat patch antenna, perhaps 6-8 dB would provide you about 2 or 3 times the signal strength in the specific direction you need it. If you look at antenna specifications, you will see a beamwidth measurement. If you were to see one with a horizontal beam width of say 40 degrees, you could make a floor plan of your place, make a 40 degree angle from your transmitter location, and see what kind of coverage you would have. I believe from your description that this would greatly help your signal.

2: I have found 1 Watt and half Watt amplifiers for the router. Would they be likely to resolve the signal strength problem? IF so, for what reasons should I avoid using them? ( legality in US, health problems caused by power of units, etc )

The 1 watt amplifier is in the $350 range I believe, and you will get considerable gain from this. However, so will your entire neighborhood. Generally, proper antenna choice and location is a much better alternative. If nothing else works, it will definately help punch through the walls. You are required to keep the total power output below a particular level, and a gain antenna with a 1 watt amp will quite likely put you over that limit.

3: I would prefer to keep power low and have repeaters for security reasons. Might you know of a way to do this without running a patch cable from the router to the bridging unit?

I believe the bridging unit you are speaking of is to allow bridging one LAN to another. It acts as a client card, but it is for connecting to multiple computers instead of just one computer like the client is. You would be looking for a repeater, which is sense would be two bridges back to back. Some gear is capable of repeating as you describe.

Your best bet, IMHO, is to focus on antenna gain and direction. I've messed with the pringles can, the helical antenna, a yagi, and built a kit colinear vertical. The vertical does very well, the others are marginal performers. I think this is mostly due to not having an easy way to test and tune them, the equipment is expensive for that frequency range and low power.

Just my two cents, good luck! It is only my opinion, based on my experience and education...I am always willing to learn, educate me!
Daron J. Wilson, RCDD
daron.wilson@lhmorris.com

 

[bluewhaleCA]

Hey Daron

Thanks for your thoughts. IYI I rechecked with another Linksys tech yesterday and confirmed that this 'bridging' arrangement is their way of offering a repeater. I have to run a hard wired patch cable from the original WAP to the new one ( different model: can not link two BEFW11S4's together in this fashion ) and PC's can access from this new WAP as well. It acts in conjunction with the original WAP.
Your thoughts mirror what I have been bringing up on the web: best practices would be to tune the antennae, not boost power. I think it might be time to visit Radio Shack and see what they have.
Thanks for the help!

Paul