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external wifi antenna?
external wifi antenna?
Hi,
I have a thinkpad T40 running OpenBSD and live in a small, nice city close to Barcelona whose city hall offers free wifi Internet to everybody.
Unfortunately they do not have a good coverage and where my building is, I don't get any signal. The card is identified by OpenBSD as ath0, which means it's Atheros.
Now, I am thinking of building an external wifi antenna but I don't have the slightest idea of how to do it. I don't have the time (unfortunately! it looks fun!) of building the antenna by myself, like here
http://www.oreillynet.com/cs/weblog/view/wlg/448
so that I'd buy one. The problem is... which one? I have seen a lot of them in ebay but I'm not sure they are for the laptop and not just for the router, to enhance its signal.
This guy seems to have managed to do exactly what I would like
http://cgi.ebay.es/ws/eBayISAPI.dll?Vie ... 0208914420
So, my question is
1) which kind of antenna do I need? I think I will need to increase the coverage radius to up to 1-2 km
2) how do I attach the antenna to the thinkpad?
3) will it be compatible with the card?
4) will the OS automatically "see" a broader range? I mean, is it something mechanical or will I have to f*** around with the driver?
thanks in advance!
Pau
I have a thinkpad T40 running OpenBSD and live in a small, nice city close to Barcelona whose city hall offers free wifi Internet to everybody.
Unfortunately they do not have a good coverage and where my building is, I don't get any signal. The card is identified by OpenBSD as ath0, which means it's Atheros.
Now, I am thinking of building an external wifi antenna but I don't have the slightest idea of how to do it. I don't have the time (unfortunately! it looks fun!) of building the antenna by myself, like here
http://www.oreillynet.com/cs/weblog/view/wlg/448
so that I'd buy one. The problem is... which one? I have seen a lot of them in ebay but I'm not sure they are for the laptop and not just for the router, to enhance its signal.
This guy seems to have managed to do exactly what I would like
http://cgi.ebay.es/ws/eBayISAPI.dll?Vie ... 0208914420
So, my question is
1) which kind of antenna do I need? I think I will need to increase the coverage radius to up to 1-2 km
2) how do I attach the antenna to the thinkpad?
3) will it be compatible with the card?
4) will the OS automatically "see" a broader range? I mean, is it something mechanical or will I have to f*** around with the driver?
thanks in advance!
Pau
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- Senior ThinkPadder
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- Joined: Tue Jan 22, 2008 8:29 pm
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There are a number of external NIC solutions which may give you better signal than the internal antenna.
A 2.4Ghz directional antenna mounted high pointed at the City Hall may give you better signal. Any long run of cable will have attenuation diminishing the benefit of a good antenna. Low lost cable tend to be thick and hard to bend around corners. Some USB NICs such as Buffalo has external antenna RF connector already but you will have to look for Linux drivers.
Some access points may be used as a wireless bridge and you simply connect it to the ethernet port on the computer.
A 2.4Ghz directional antenna mounted high pointed at the City Hall may give you better signal. Any long run of cable will have attenuation diminishing the benefit of a good antenna. Low lost cable tend to be thick and hard to bend around corners. Some USB NICs such as Buffalo has external antenna RF connector already but you will have to look for Linux drivers.
Some access points may be used as a wireless bridge and you simply connect it to the ethernet port on the computer.
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I've found that my Cisco B card gets better reception than my Atheros card for some reason. Maybe it is just a problem with the Linux drivers or something. Of course, that's assuming any card can get reception at that distance.
If you have to get a fancy antenna (1-2km=probably fancy directional antenna), it would probably won't be plugging into your Thinkpad directly. As mentioned earlier, you will need to mount it in a high place, and the antenna cable should be as short as possible. Ideally you'd either have an extra computer close to the antenna that would then convert to ethernet or such, or you'd find a a USB wireless card with an antenna connector, and the extra distance would be covered by an upto 15ft USB cable.
Here's a whole list of cards, and whether they have connectors..
If you have to get a fancy antenna (1-2km=probably fancy directional antenna), it would probably won't be plugging into your Thinkpad directly. As mentioned earlier, you will need to mount it in a high place, and the antenna cable should be as short as possible. Ideally you'd either have an extra computer close to the antenna that would then convert to ethernet or such, or you'd find a a USB wireless card with an antenna connector, and the extra distance would be covered by an upto 15ft USB cable.
Here's a whole list of cards, and whether they have connectors..
If you had easy access to the (by the way REAL tiny!) U.FL. Hirose connectors on the miniPCI WLAN interface, you could simply detach the cable presently routing to one of the internal antennas (you know, those which are located at either side of the display), and in stead connect an external antenna directly to the Atheros card. A practical solution as per this idea would be to have a short cable with the U.FL. Hirose connector in one end (connecting to the miniPCI), and then route this cable out through, say, the fan exhaust. Then, directly at the outside of the laptop, you would mount a reverse-SMA connector on the cable (not easy, trust me, because these cables are SO small!), and then you could have a thicker (low loss!), long cable going up to a high-gain outside external antenna, which was pointed towards the city hall. This is however an quite fragile suggestion, since a such small cable coming into your laptop is very easily being subject to become damaged... and you will need to connect and disconnect this cable each time you want to move your laptop - not too smart (a colleague of mine used this approach for some time, but he got tired of it, and ended up ordering an internet connnection of his own).
In stead, I would suggest that you get an USB WLAN "dongle", but one of those with an external antenna that is connected through a standard (typically: Reverse) SMA-connector. Next, get a sufficiently long, low-loss cable and a parabolic antenna (some 24 dBi gain, e.g.), mount the antenna at a point having preferably line-of-sight to the WLAN source (the public router/access point), and disable the Atheros internal miniPCI interface (or, is this perhaps even not necessary?). If your Linux will support the particular USB WLAN dongle, then you're in business... otherwise, well, you're in trouble!
A few images showing what type of USB WLAN "dongles" I am having in mind are something like this no. 1 or this no. 2 or this no. 3. An example of an outdoor, high-gain parabolic WLAN antenna is shown here - there are TONS of such available, and at a variety of prices; Google around a bit, and you will find much cheaper ones.
I also recall having seen what is called WLAN "range extenders", which might be of use, but I have absolutely zero idea of how well they work; try read user-reviews at e.g. Newegg or Amazon etc. One example of such product is the DWL-G710 High Speed 2.4GHz (802.11g) Wireless Range Extender.
Good luck with this project - but be prepared to invest a bit of time and energy!
Best regards,
Johan
In stead, I would suggest that you get an USB WLAN "dongle", but one of those with an external antenna that is connected through a standard (typically: Reverse) SMA-connector. Next, get a sufficiently long, low-loss cable and a parabolic antenna (some 24 dBi gain, e.g.), mount the antenna at a point having preferably line-of-sight to the WLAN source (the public router/access point), and disable the Atheros internal miniPCI interface (or, is this perhaps even not necessary?). If your Linux will support the particular USB WLAN dongle, then you're in business... otherwise, well, you're in trouble!
A few images showing what type of USB WLAN "dongles" I am having in mind are something like this no. 1 or this no. 2 or this no. 3. An example of an outdoor, high-gain parabolic WLAN antenna is shown here - there are TONS of such available, and at a variety of prices; Google around a bit, and you will find much cheaper ones.
I also recall having seen what is called WLAN "range extenders", which might be of use, but I have absolutely zero idea of how well they work; try read user-reviews at e.g. Newegg or Amazon etc. One example of such product is the DWL-G710 High Speed 2.4GHz (802.11g) Wireless Range Extender.
Good luck with this project - but be prepared to invest a bit of time and energy!
Best regards,
Johan
IBM T42p's (2373-Q1U & -Q2U): 2.1 GHz, 15" UXGA FlexView, 2 GB RAM, 128 MB FireGL T2, 128 GB 1.8" SATA SSD, IBM a/b/g, BT, Win 7 Ultimate
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Why don't you just get an Access Point with jack for external antenna, and put it beside a window - you might not even need an external antenna, if you get a good access point. Good Access Points can function as WLAN bridges, and that's all you need...
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Hi,
thanks a lot for the answers. I am learning a lot.
I have been thinking and I have found this
http://www.wiretex.de/shop/product_info ... stung.html
It's in German, but I think you can uderstand the description well.
There's a good offer in ebay right now. Do you think this will be enough to get 1km?
Cheers,
Pau
thanks a lot for the answers. I am learning a lot.
I have been thinking and I have found this
http://www.wiretex.de/shop/product_info ... stung.html
It's in German, but I think you can uderstand the description well.
There's a good offer in ebay right now. Do you think this will be enough to get 1km?
Cheers,
Pau
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- Senior ThinkPadder
- Posts: 2908
- Joined: Tue Jan 22, 2008 8:29 pm
- Location: San Jose, CA
For 1km, you need something like these:
http://www.radiolabs.com/products/anten ... leyagi.php
http://www.hyperlinktech.com/web/antenn ... tional.php
http://www.radiolabs.com/products/anten ... leyagi.php
http://www.hyperlinktech.com/web/antenn ... tional.php
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X61t 7762-B6U dual touch IPS/64GB SSD
X32 2673-BU6/32GB SSD
755CDV 9545-GBK Transmissive Projection LCD
T60 2623-DCU/SXGA+ IPS/ATI X1400
T43p 2668-H8U/UXGA IPS/ATI V3200
R50p 1832-NU1/UXGA IPS/ATI FireGL T2
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755CDV 9545-GBK Transmissive Projection LCD
- this won't work, because your problem is two-fold (or, rather, speaking in radio terms: Two-way):pau wrote:I have been thinking and I have found this
http://www.wiretex.de/shop/product_info ... stung.html
It's in German, but I think you can uderstand the description well.
There's a good offer in ebay right now. Do you think this will be enough to get 1km?
a) You need to obtain (or establish) a certain, minimum amount of received signal power from the WLAN "host" (in the city) to connect into your receiver, so that it will be able to provide a sufficient signal-to-noise ratio and
b) You need to transmit a sufficiently strong signal "out in the air" so that it can be detected at the receiver in the other end with the same minimum signal-to-noise ratio.
The thing you have found here won't have (much) influence on a) but it will help b). However, if not simultaneously fulfilling a) AND b) then there's no two-way connection (which is of course what you want in a WLAN system!).
If you connect an external antenna directly to your WLAN interface (not easy, but just to explain the principle), then this antenna will both "amplify" the received power from the WLAN transmitter somewhere AND the antenna will also help create a stronger signal (higher power-flux density) at the remote receiver; the signal you transmit. What you have in your ThinkPad is a very low-gain, or "poor", combined receive/transmit antenna; "poor" in the sense that is is almost omnidirectional, and hence not capable of directing the energy in one, "sharp" direction, which is what YOU want in the present situation. However, the reason why the internal Thinkpad antenna is designed to work like this, is that in typical office environments you won't know from which direction the signal is being received (owing to indoor multipath reflections)... so the antenne has be be sensitive in all dirctions, and hence it is by nature low-gain (somewhat omnidirectional!).
Think of an antenna like this: It is capable of directing the energy, that is coupled into it, either into all directions (an "isotropic" or omnidirectional antenna), and in this case giving a relatively low signal (power-flux density) in all directions, OR it may be designed to direct the energy only into ONE "sharp" direction (at the expense of no energy neither transmitted to nor received from other diections). Receive antennas are a bit harder to understand, but if I tell you that there is the "antenna transmit-receive relation" that says that a (passive) antenna will work identical as a transmitting and a receiving antenna, then just think of the antenna from the transmit perspective.
Recall the fundamental law of physics; "Conservation of energy"; no energy ever appear (out fo nothing) or dissapear; energy may be transformed, transmitted, dissipated as/into heat - but fundamantally, it doesn't appear or dissapear. Because of this the term "amplification"" or "gain" of an antenna may be a bit confusing.
All this to say that you need a high-gain (directional) antenna to be able to receive a sufficient amount of power from the WLAN "host"... and to be able to create a sufficiently stong signal in ONE direction (with your low output/transmitter power); in the dirction towards the WLAN "host". Try get an impression of the antenna-gain needed through using a WLAN link-planner, such as e.g. Link Planning for Wireless LAN (WLAN) - the first one found if searching for "wlan link planner" using Google.
You're almost there...
PS: An alternative would be to order a, say, 1 Mbit ADSL connection and share it with 10 people... that would work and keep your costs very small - and you may bill the other nine a small service-fee, so you end up having internet entirey free yourself...
Best regards,
Johan
IBM T42p's (2373-Q1U & -Q2U): 2.1 GHz, 15" UXGA FlexView, 2 GB RAM, 128 MB FireGL T2, 128 GB 1.8" SATA SSD, IBM a/b/g, BT, Win 7 Ultimate
IBM T42 (2373-N1G): 1.8 GHz, 15" SXGA+ FlexView, 2 GB RAM, 64 MB Radeon 9600, 64 GB 1.8" SATA SSD, IBM a/b/g, BT, Win 7 Ultimate
IBM T42 (2373-N1G): 1.8 GHz, 15" SXGA+ FlexView, 2 GB RAM, 64 MB Radeon 9600, 64 GB 1.8" SATA SSD, IBM a/b/g, BT, Win 7 Ultimate
That's the kind of answer I was looking for. Being (Theoretical) Physicist, you have chosen the correct vocabulary to explain the problem.
To sum up: You say that that ebay item will help me to transmit the packets the laptop send when asking for a connection; it will help to transmit the information but probably will not be strong enough yet. And to gather the packets the router in the City Hall broadcasts it will be more or less useless.
Why isn't this a symmetric problem? I always thought that, if I can get the information, then I can send it as well with the same SNR (signal to noise ratio). Does it depend on the chipset? Are there more powerful wlan chipsets than others?
And, in order to fix the problem... If I buy that ebay item AND and additional big ("big" as in "20 dBi") antenna and substitute the 5 dBi that comes with the ebay athereos card, will I have solved the problem?
I think I am approaching the problem wrongly because I am looking for an immediate answer and I have not had the time to read in calm all the information.
In any case, this forum was really a good discovery!
To sum up: You say that that ebay item will help me to transmit the packets the laptop send when asking for a connection; it will help to transmit the information but probably will not be strong enough yet. And to gather the packets the router in the City Hall broadcasts it will be more or less useless.
Why isn't this a symmetric problem? I always thought that, if I can get the information, then I can send it as well with the same SNR (signal to noise ratio). Does it depend on the chipset? Are there more powerful wlan chipsets than others?
And, in order to fix the problem... If I buy that ebay item AND and additional big ("big" as in "20 dBi") antenna and substitute the 5 dBi that comes with the ebay athereos card, will I have solved the problem?
I think I am approaching the problem wrongly because I am looking for an immediate answer and I have not had the time to read in calm all the information.
Thanks. English is not my mother tongue and I could not figure out what the English terms could be to express that. Sometimes it is very frustrating to spend hours in front of a search engine just because you don't know the correct term.Try get an impression of the antenna-gain needed through using a WLAN link-planner, such as e.g. Link Planning for Wireless LAN (WLAN) - the first one found if searching for "wlan link planner" using Google.
In any case, this forum was really a good discovery!
OK, pleasure of providing you with some ideas and a bit of inspiration!
To just comment your questions about the RECEIVE signal strength and the TRANSMIT signal strength. Assume there was a public WLAN access point mounted up on the Moon! That would be clever, since many users down here could "see" it, wouldn't they? OK, next let's assume that this Moon-access point had a very small, omnidirectional antenna (so that not only we "humans" could hear and use it, but so that also Extra-Terrestrial aliens elsewhere could take advantage of it!). Well, in order for YOU down in Barcelona to be able to "hear" the signal from the Moon, the WLAN transmitter up there would need to be REAL big. Fortunately, the Moon has plenty of space so the engineers therefore had just placed a 100.000.000.000 Watt transmitter up there. (I should add here, that this BIG transmitter uses solar power only, so we're certainly talking about a very environmentally friendly, CO2-correct solution here... particularly as they don't even HAVE any Oxygene up there, at least not on gaseous form!). Net result: Wow, what nice and BIG signal you would receive in Barcelona, you bet! But... when your tiny miniPCI WLAN transmitter put out its (I don't what - say 100 milliwatt?), then... would you believe that the signal received from YOU all up on the Moon would be strong enough to be detectable up there - with the lousy, low-gain antenna used up on the Moon?? Ooh, no, sorry - your signal would be way down in the thermal (and cosmic) background noise. So, this would be a one-way communication: YOU could hear THEM, but they would NEVER hear you up on the Moon. Now, replace "Moon" by "City Hall in Barcelona", and you've got the point (I hope!).
I just Google'd a bit (too tempting to being able to resist!), and there is of course a HUGE amount of sites discussing how to obtain long-range WLAN links, also with low budgets. One "altruistic educational project" -- here -- list a bunch of experimental projects, incl. the ultimate low cost using only a Chinese cookware scoop & a USB WiFi adaptor; the so-called "WIFRY" or "WOKTENNA"... - see the image here
Many of these projects seems to include a certain amount of, well, "empirical engineering" (or experimenting), and I am not sure that all work equally well, but hey, when I was a radio amateur (as a young man!), much of what I did honestly wasn't that extensively based on theory and some of it worked anyway! I think you need to find out for yourself if you want to "play" with this, and build your own antenna, and get all the other components, or if you rather want a fixed and ready-to-run solution here and now. In the latter case, go to some WiFi-shop in Barcelona, grab your credit-card out of the wallet, slam it on the desk, and say to them "just give what is necessary, plug-and-play, no hassle or crap, and I have plenty of money but little time to play!" You need to decide what route to go...
About not being English from the beginning, no problem - many of "us" here on the forum are also not that, but we try to the best of our ability to make ourselves understood... with a little mixed result! Anyway, if you would like to discuss this issue with your German countrymen, I suggest you visit the German ThinkPad-Forum.de.
Try look around for yourself for "WLAN long range links" or "WLAN range improvement" etc. etc. - I am totally sure that what you are working with has been discussed many, many places, and that many interesting, usable AND cheap suggestions can be found.
To comment the CardBus/PCMCIA WLAN card you have found; yes, something like ths may be brought to work (although I think is is quite expensive), but it most likely would need to have the presently-mounted omnidirectional antenna replaced by a directional, high-gain antenna. Also, you would need an amount of low-loss coaxial cable connecting the antenna to the CardBus/PCMCIA interface... adding cost. If you could in stead find a cheap WLAN-USB "dongle", one with an external antenna (this antenna also typically being a low-gain, omnidirectional), and then connect a high-gain antenna directly to the USB-WLAN "dongle", then you would just need to get the necessary amount of USB-cable to connect your ThinkPad to the now integrated USB-WLAN-dongle-AND-antenna... cheaper, better (since you would minimize the 2.4 GHz cable-loss between the antenna and the WLAN receiver).
...and, yes, building and experimenting antennas IS fun, but you need to be prepared for that they does not always work the first time!
Best regards,
Johan
To just comment your questions about the RECEIVE signal strength and the TRANSMIT signal strength. Assume there was a public WLAN access point mounted up on the Moon! That would be clever, since many users down here could "see" it, wouldn't they? OK, next let's assume that this Moon-access point had a very small, omnidirectional antenna (so that not only we "humans" could hear and use it, but so that also Extra-Terrestrial aliens elsewhere could take advantage of it!). Well, in order for YOU down in Barcelona to be able to "hear" the signal from the Moon, the WLAN transmitter up there would need to be REAL big. Fortunately, the Moon has plenty of space so the engineers therefore had just placed a 100.000.000.000 Watt transmitter up there. (I should add here, that this BIG transmitter uses solar power only, so we're certainly talking about a very environmentally friendly, CO2-correct solution here... particularly as they don't even HAVE any Oxygene up there, at least not on gaseous form!). Net result: Wow, what nice and BIG signal you would receive in Barcelona, you bet! But... when your tiny miniPCI WLAN transmitter put out its (I don't what - say 100 milliwatt?), then... would you believe that the signal received from YOU all up on the Moon would be strong enough to be detectable up there - with the lousy, low-gain antenna used up on the Moon?? Ooh, no, sorry - your signal would be way down in the thermal (and cosmic) background noise. So, this would be a one-way communication: YOU could hear THEM, but they would NEVER hear you up on the Moon. Now, replace "Moon" by "City Hall in Barcelona", and you've got the point (I hope!).
I just Google'd a bit (too tempting to being able to resist!), and there is of course a HUGE amount of sites discussing how to obtain long-range WLAN links, also with low budgets. One "altruistic educational project" -- here -- list a bunch of experimental projects, incl. the ultimate low cost using only a Chinese cookware scoop & a USB WiFi adaptor; the so-called "WIFRY" or "WOKTENNA"... - see the image here
Many of these projects seems to include a certain amount of, well, "empirical engineering" (or experimenting), and I am not sure that all work equally well, but hey, when I was a radio amateur (as a young man!), much of what I did honestly wasn't that extensively based on theory and some of it worked anyway! I think you need to find out for yourself if you want to "play" with this, and build your own antenna, and get all the other components, or if you rather want a fixed and ready-to-run solution here and now. In the latter case, go to some WiFi-shop in Barcelona, grab your credit-card out of the wallet, slam it on the desk, and say to them "just give what is necessary, plug-and-play, no hassle or crap, and I have plenty of money but little time to play!" You need to decide what route to go...
About not being English from the beginning, no problem - many of "us" here on the forum are also not that, but we try to the best of our ability to make ourselves understood... with a little mixed result! Anyway, if you would like to discuss this issue with your German countrymen, I suggest you visit the German ThinkPad-Forum.de.
Try look around for yourself for "WLAN long range links" or "WLAN range improvement" etc. etc. - I am totally sure that what you are working with has been discussed many, many places, and that many interesting, usable AND cheap suggestions can be found.
To comment the CardBus/PCMCIA WLAN card you have found; yes, something like ths may be brought to work (although I think is is quite expensive), but it most likely would need to have the presently-mounted omnidirectional antenna replaced by a directional, high-gain antenna. Also, you would need an amount of low-loss coaxial cable connecting the antenna to the CardBus/PCMCIA interface... adding cost. If you could in stead find a cheap WLAN-USB "dongle", one with an external antenna (this antenna also typically being a low-gain, omnidirectional), and then connect a high-gain antenna directly to the USB-WLAN "dongle", then you would just need to get the necessary amount of USB-cable to connect your ThinkPad to the now integrated USB-WLAN-dongle-AND-antenna... cheaper, better (since you would minimize the 2.4 GHz cable-loss between the antenna and the WLAN receiver).
...and, yes, building and experimenting antennas IS fun, but you need to be prepared for that they does not always work the first time!
Best regards,
Johan
IBM T42p's (2373-Q1U & -Q2U): 2.1 GHz, 15" UXGA FlexView, 2 GB RAM, 128 MB FireGL T2, 128 GB 1.8" SATA SSD, IBM a/b/g, BT, Win 7 Ultimate
IBM T42 (2373-N1G): 1.8 GHz, 15" SXGA+ FlexView, 2 GB RAM, 64 MB Radeon 9600, 64 GB 1.8" SATA SSD, IBM a/b/g, BT, Win 7 Ultimate
IBM T42 (2373-N1G): 1.8 GHz, 15" SXGA+ FlexView, 2 GB RAM, 64 MB Radeon 9600, 64 GB 1.8" SATA SSD, IBM a/b/g, BT, Win 7 Ultimate
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The chipsets used in these WiFi devices are made of CMOS. While they can work at 2Ghz and above, it is neither optimized nor efficient to do so. For instance, the Belkin Pre N router (old version) use an Airgo chipset. While the consumer version use a direct RF CMOS output, the commercial version uses a GaAs FET output device. This version has much higher output, efficiency and better linearity across the entire band. Mobile phone output devices with few exceptions are all GaAs based for better performance.pau wrote:...the City Hall broadcasts it will be more or less useless.
Why isn't this a symmetric problem? I always thought that, if I can get the information, then I can send it as well with the same SNR (signal to noise ratio). Does it depend on the chipset? Are there more powerful wlan chipsets than others?
And, in order to fix the problem... If I buy that ebay item AND and additional big ("big" as in "20 dBi") antenna and substitute the 5 dBi that comes with the ebay athereos card, will I have solved the problem?
...
The directional antennae use the principle of spatial diversity. So they just direct the output energy into a narrow angle in order to reach further.
The receiver design is also critical. For instance the LNA (low noise amplifier) used in Direct Broadcast Satellite recievers are almost always made with Low Noise GaAs FET. The have much better signal to noise ratio. Same with DAB (direct audio broadcast) receiver designs.
Nevertheless WiFi almost always use RF CMOS for low cost.
T60p 2623-DDU/UXGA IPS/ATI V5200
T60 2623-DCU/SXGA+ IPS/ATI X1400
T43p 2668-H8U/UXGA IPS/ATI V3200
R50p 1832-NU1/UXGA IPS/ATI FireGL T2
X61t 7762-B6U dual touch IPS/64GB SSD
X32 2673-BU6/32GB SSD
755CDV 9545-GBK Transmissive Projection LCD
T60 2623-DCU/SXGA+ IPS/ATI X1400
T43p 2668-H8U/UXGA IPS/ATI V3200
R50p 1832-NU1/UXGA IPS/ATI FireGL T2
X61t 7762-B6U dual touch IPS/64GB SSD
X32 2673-BU6/32GB SSD
755CDV 9545-GBK Transmissive Projection LCD
... my countrymen are the Catalans. I have written Berlin because I was living there when I signed up for this forum. Unfortunately I had to leave Berlin but I hope that I can go back one day in the (close?) future.Anyway, if you would like to discuss this issue with your German countrymen, I suggest you visit the German ThinkPad-Forum.de.
Johan, a big THANK YOU, that page looks FUHN!!! I do have the money to behave the way you described but I must must must must try one of those self-made antennae!! I had seen some of these things in the internet, sometimes, yes, but I really could not believe them. The description was very lame and it looked all fake.
I must try it. The only problem seems to find the focal point in the antenna... I will think about it. I should grab the Optics book from the university. If the frying pan has a well-defined volume it should not be a problem.
My only problem here will be the usb wifi adapter. I have to make sure it'll work with OpenBSD, which is not obvious.
Wait for news; I'll come back to you when I have news on the experiment!
Cheers,
Pau
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