Bekijk de volledige versie : WiFi power output on oleg

23-06-2008, 15:39
I've been searching quite a while on these forums about wifi transmit power changes.
I decided to open this issue again, because nothing has been found yet how to properly increase the output, no offense to oleg ofc, because the original asus firmware also doesnt work with it;)

I've been testing many tricks I found in this forum, but nothing seems to work.
what did I do:

nothing connected to the router, no usb devices.
set the different values of strength in the webadmin and measured it all with a professional wifi detector.
I made sure that the nothing was in between the router and the client and that the power value could raise and lower properly (not too close to the router).

it didn't really matter what power value I chose, the output stayed the same. I did noticed, that the transmit power was more stable on higher values than on lower values.
now I'm wondering... why is this value available while it doesn't change anything interesting, it might give you that little extra when you have nearly no reception... but that wouldn't be more than 1m difference.

I Know that the values in the webadmin are mW, so I looked it up on wikipedia: http://en.wikipedia.org/wiki/DBm

as you can see in the table,the value 84mW is quite a bit under the Europian allowed 100mW. not that it would change anything as the value settings don't work... but asus assume you would only transmit on 17mW wich isn't as good as a laptop....
I've heared that openWRT has better wireless boosters, so maybe it's an idea to look up some things they did to amplify their networks, I mean... it's open right:p

I'm prepaired to make a graph with the best wireless output settings for the asus routers with olegs firmware... but then I will need oleg help with this:rolleyes:
I hope you will:)

05-07-2008, 09:21
This will be extremely interesting WPTE.
I am sure alot of users will look forward for your results.
I have some experience in long distance links in .b and .a and i can tell you not only power is important in a quality link, but mostly SNR , and most cards tend to kill quality of signal when is pushed to limits (raising power).
In this matter some word have drivers too.
But what i mean with this is real help is not a wifi analyser, but a troughpout determination with all encryptions and modes/power will help more because here we have short distance and powers beyond 80-100mw will do nothing good, only choke rf preamplifiers.
The best thing to do allways is put best antenna you can get.
I will try shortly with a dublusectorial 5dB from some PROXIM pci clients, wich have a professional manufacturing and is only 10 cm long :) .
You now, the 80 mw is alot of power for this aplication, keep in mind the wifi cards on laptops is 15-30 mw mostly, and you will see your ap from far but not or bad connection because the minipci cant keep up and push this amount of power.
So, the best for us is the best throughput we can get with quality drivers and settings, and of course antenas.
I can detaliate more of this if you want (real construction, diferrences and performances of different antenas), but remember the "antena" in router and laptops is a piece of wire about 2 cm long ....the bad concept you can get but costs is almost 0 of thise ... shame for all who product this.
I can put here some pictures to see a real 5 dB sectorial .b/.a from proxim, and to understand how we fight with paper swords.
Y crack alot of thise sticks who is callit antena, and allways i find the 2 cm wire inside, no matter how long and thick look from outside, grrr.

05-07-2008, 18:03
I know a good antenna is a good start for better wifi:)
I have a wl-500w tough, so no changeable antennas:(
a solution so far I found: cooling
I have a laptop cooler placed under the router, and it seems to increase the wifi output:p
I've tested it with my pda, and the value changed from 16 to 10 (the lower the better the signal ofc;)) placed straight on the router:D

the antenna's from asus aren't that bad I think, the longer the antenna doesn't increase your output, however, there is a golden lenght where it has max output.
you see, the frequency of 2.4GHz-2.5GHz is quite big... you only need a small antenna for it, a giant antenna would be ineffective;)

look at this site:
http://kb5wck.com/antenna_calcs.php (scroll down)
it's a bit wrecked on IE, but it's a good calculater.
and if you fill in everything, the antenna only needs to be 6cm;)

also a nice theoretical physics thing:
if you hang up a coax cable near the antennas, not connected, the coax cable will absorb, but also vibrate with the antenna's to make a more clear signal in difficult positions. worked for me several times:)

05-07-2008, 19:01
Y dont was too clear i am afraid.
The total lenght of a antenna can be 1,4m (a 19 dublusector 19 dB) and more ofcourse, is not important here or different forms, what i mean is the design, the 2 cm is calculated with a hot point to resonance around 2,4 gHz.
The design of a low cost antenna cant beat this concept "a piece of wire", that's a "happy" news for any who product this so callit antennas, but you know, size matter :), but not for links under 100m.
Your piece of coaxial wont clean anything, but on a atent proportion will be a resonator of the first resonator (antenna) so you can get in apearence a better signal, but mostly this will afect the WSVR and lobe of your hotspot.
In tiny distances this wont matter anyway (under 100m), but is not a real plus nor minus.
In the matter of cooler the problem look to me in the proper cooling of unit (i never have a w to see this for real).
My gp is half open and the power adapter is drilled with alot of holes to fight with a tendence of almost all electronics today, the under cooling to archieve a exact period of life of a product, no matter what is that.
I can explain more here but the post will grow offline.
The cooling in wifi is another special capitol, based first on the technology of the rf chip, the GeSI, meaning Germaniu-Silicon.
The germaniu was on first transistors but loose fight in front of silicon, because of some important caracteristics : the "randament" of germaniu is way bad (loose electroni, production of heat is high, tensions and currents capable is way lower, and some others), but have a high capability to up in frequency, so is used on the very high frequency stages of signal.
But heat can damage performance of a higly integrated chip who have ge inside, so you really can get a better or stable signal cooling the unit :).
But this pass the intended post.
I will put here some inside pictures of a sector antenna, who is best for us (there is more omni,panels,directional) wich one with different characteristics, but for low distance high performance and stability is sectors (simple or double).
In 10 cm long/2cm wide PROXIM (and other quality productors) can put a real 5 db sector wich is a high performance antenna and archievement ^^.
This is a best point to start to archieve high speed/stability of links, but will help alot a determination of real throughput of thise cards on a determined drivers and conditions.
The real diference in a quality microwave resonator and a piece of wire is the wire will collect ALL rf junk and choke on the GeSI chip, who must clear and handle and put some performance out no matter what :) but a quality antenna will "filter" and serve only the spectrum for is calculated.
I stop here hopping i was clear somehow and someone get some.
The first quality of mine is not explanations ^^ sorry.

LE. :
I see now inside of a .w and is ease to put some connectors on case then voila, any antennas you want.
Will be a mechanical hack, and ease one .
But the real hack and the one with best results will be the antenna from laptop, i study my lap for this but is a metallic case model (toshiba portege m200) and no enough clear room for another antenna, have only 6 mm on a top plastic, the rest is all metall.
Bad news for me, but not all laps are metallic ^^.
The antenna on router have roughly 3-4 db, and are 3 in .w case, but our laptops have a indecent 1-2 db and the badest design you can find, thats the sweet spot y will say ...

If i go back 2 years, my lap was a toshiba satellite pro, who have a 15x15cm resonator from a 17db MTI panel, 2,4 ghz, put behind lcd panel (inside case), wich beat any you can imagine, that help me connect anywere you can imagine.
That was a painfull hack, because the panel cost like 80 eur if i remember corectly.
Now the lap is in use by my wife ^^,on much more domestic utilities, like movies or browsing from home.
For a home use this is overkill, but this help me connect on my network 6 km long, who have a 10db sector on ap, and 100mw power.

07-07-2008, 20:33
sounds interesting:)
this treath seems to get a lot of attention on the number of views, unfortunately mr Oleg himself doesn't seem to notice:( maybe he's on holiday:p

for testing purposes I guess we need the following:
test in an open field
test every channel without protection
test on the best channel with all security features
measure each 5m how strong the signal is:)
and ofc we need to change the output value
if correct, we could be able to get the right value trough maths:)

I have also looked into the sources of the firmware of asus and oleg, they seem to use the same drivers for the wireless part.
I tried to find the openwrt sources... but I kinda couldnt find it because there are so many files on that site :eek:

07-07-2008, 22:48
Y see here the "classic" approach :
1. stability
2. throughput
3. both
Back in time i go always with stability, and second throughput, but one method to determine and improve the stability is determinations using throughput :D.
Maybe this sound strange for some, but is a very good method.
The procedure is this :
1. setup of a best determined and reported by equipment link signal.
2. setup of a big transfer between points then play with channels and antennas to archieve the best rate of transfer (wich is not always with best signal because of reflections or interferences or too powerful signal will choke the preamplifiers).
Here the encrypting is missed because the enterprise equipment is well tested and usually work ^^.
This work in point to point fixed links, but in mobile job is way complex.
Here we can learn from mobile cells, where is architecture of 4 sectors antenna for best and stable coverage, (there is "omnidirectional" antennas too but not used because their bad coverage and bad form of hotspot who is created).
Because telephones "grow" smaller :) and power limitations is kicking, the best aproach is 4 sector antenna put it in 360 grades architecture (if you cant improve mobile station, improve hotspot raising coverage and receiver sensivity).
This is way to go for home appliance too (we in this case).
On another hand for us in procedure above on point 2 will apear another "play" : with encryptions to determine wich is best supported by the drivers.
I see good equipment, enterprise class, wich work unstable with 128 AES, and rock solid with 256 AES.
This is the thing for us to determine ... the best encryption and channel (upper class or lower), and another fancy settings (i mean here AfterBurner, wich is not allways supported but can improve or damage throughput on regular cards,Frame Bursting,WMM).
But this can differ from you (with .w unit) wich have a different wifi card, and us with .gp ...
Usually firms tend to have an "approach" to do things, so maybe your results will apply to us anyway.
Will be very interesting to see such a determination, so y will look with much interes on your results ^^.
But we have not too fall in mistake to raise alot of power from fixed unit, because is stress for nothing :), the link itself wont benefite from this with nothing ... only our neurons will get well cooked and roasted ^^.
This philosophy is induced by analog radio, the raising power on station the longer coverage, but we all not forget wifi is 2 way radio ^^, the powerful station wont benefit with any if the other end of link is not the same, and alot of power is not good for throughput on digital radios, they love clear signal not raw power.
Writing this phrase i see an analogy with women and man lol ^^.

LE : No need for every channel test, only 1,6,11 will clear all for us, but the open space is a must, and ecrypting will be wpa or wpa2 with aes or tkip, is enough, nobody use wep i hope.
But big importance on throughput will have the :Fragmentation Threshold, RTS Threshold, and some DTIM Interval, Frame Bursting, Regulatory Mode.
Data rate, multicast rate, basic rate i will let them default.
For things to stay clear i use back in time AirMagnet Laptop Analyzer, is a milestone in wifi, maybe they have a trial version now, i recomand you try this, will clear alot.
I remember another, "observer suite", is good too.
And measuring from 5 to 5 meters is overkill, maybe 50 to 50 ... but this will help anybody ?

08-07-2008, 11:35
but we all not forget wifi is 2 way radio ^^, the powerful station wont benefit with any if the other end of link is not the same.

And measuring from 5 to 5 meters is overkill, maybe 50 to 50 ... but this will help anybody ?

yeh, but we try to get the wifi stronger of the router, not of the laptops and other stuff;)
5 to 5 meters is not really overkill... because with 50 to 50 I have only 2 measurements:D
and with 5 to 5 you get a nice curve, and with some maths you can solve the maximum distance so wind doesnt carry the signal away;)

08-07-2008, 16:46
We try to get wifi on router "better" not "stronger", or i get it wrong .
And better in a such way to provide a better link, not just raise power, no ?
What i mean about a such long speak about antennas, is for a 3 db win you will need to double the power, and you will get win only on a head of link, wich is nothing in a better link point of view.
But better with 3 db antena you will get 3 db on radiate power and 3 db on receive sensivity, wich will extend your real basic coverage.
We cant look and think at wifi improvement ,only in a single point of view, the ap or only the client, both are welded together.
The gain of a 3 db if huge, but doubling power on wifi card is the same ...if you start from 80mw allready.
And i think about security, hate to have 500 meters around my home coverage...
I use this router as my main router and bittorrent machine, and in my home y will go with a better antena and lower power, thus improving sensitivity only, and maybe all my posts is with this in mind...
You can think on a double power double sensitivity if put a +3 db antenna :).
Maybe some will need high coverage but this is another point of view, with different approach.
You WPTE must specify what is your first goal ^^, so i can get it correctly, and apply.

08-07-2008, 21:14
wifi transmit power changes.

that's what I've said...
screwing a new antenna on a router is something anyone can do.
I neither do worry about troughput speed and stability because I almoast get the theoretical usefull dataspeed on wireless and wire and keep a low ping at all times.

I want to increase to transmit power, to get the signal further.. you see, some ppl want their internet back in the garden while the router is at their home.
There has been a post about a resistor on the wlan card that keeps the sensitivity low, for better sensitivity that is just the answer, some problems are hardware, not software.:)

08-07-2008, 23:26
So, y understand you play with settings and archieve almost this hardware can do.
That is good.
And you need longer coverage ?
Ah, for that the only way is a omni or better sector or panel or some directional grid or offset antenna :D, depend what kind of radio lobe you need there.
I am not skillful in linux but is there some iwconfig utility who can show you the signal router receive from you, or maybe http interface.
Must look allways there, not to get fooled by powerful signal received in garden by you lap, after raising 2w wifi power on router.
You will get let say -60dbm on 300m reported by lap, but the router will see the lap with -90dbm, if will see anything ...
The best can hapend lap will connect with router, will report good signal, but link will raise sky hi on a 10kbs transfer rate...
Is necessary to ensure sensitivity on router or raise the same power from wifi card in lap.
Sorry for my english, i cant explain this more clearer ..

LE : i have a ideea to explain this ^^:
Two ppl want to speak from a 100m distance, ok ?
They cant because of high distance.
But wont help with any if you buy for one of them a powerful station with speakers, because the other guy will hear the first but first still wont hear anything from second so still cant be a dialog there...must buy speakers for second too.
This is best i can do :D.

09-07-2008, 13:38
allright, I'll keep it short this time:
the problem is not that the laptop can't say anything back over that great distance...
neither the problem is, that we need a better antenna...

the problem is: we have a value in the router, if we change it, the output is not changed. this is most likely a software problem as other firmwares seem to succeed in changing the output.

the basic working mechanism is: input -> process -> output
so if:
2 -> process -> 10
6 -> process -> 10
something is wrong at the process:D

easy words?:p

09-07-2008, 19:53
Y agree with you, its a software problem for sure.
Can be drivers or implementation, but usually driver can change output power not only by specific fixed settings but dynamically too.
This is an area where i cant help...
So, y wait here, "looking good" ^^ for your results.

09-07-2008, 23:49
Y agree with you, its a software problem for sure.
Can be drivers or implementation, but usually driver can change output power not only by specific fixed settings but dynamically too.
This is an area where i cant help...
So, y wait here, "looking good" ^^ for your results.

I guess so, still waiting for mr Oleg:)
does anyone know how to find the correct sources of the openWRT firmware for asus routers?

oh, and a small thing to poiu:p
I'm not sure if you noticed, but it's "I" instead of "Y"
otherwise you say "why":p

10-07-2008, 00:30
Tnx wpte, i will try to learn more . ^^

10-07-2008, 14:20
today I tried dd-wrt and open wrt
I found out dd-wrt is quite good on settings (a lot) and tried to get my wifi stronger.
unfortunately, it didn't really matter what settings I chose, the wifi didnt get stronger or weaker. and the maximum speed dropped from 270mbit to only 130:(
however, the maximum strenght I found had a value of 9 (lower the better), instead of the 10 that oleg gave me.
not really a big difference, but the dropped speed is defenately a no go:rolleyes:
the fun part is tough, that you can create 10 wireless networks or something :D

the open wrt did flashed, but didn't quite boot:p
unfortunately I've not been able to test it out, and I had some trouble flashing oleg back due to weird factory defaults:confused:

28-07-2008, 17:44
Any news wpte ?
Hope your ASUS is ok after tinkering with all kind of firmware..

28-07-2008, 18:02
Any news wpte ?
Hope your ASUS is ok after tinkering with all kind of firmware..

yeh my asus is ok mate;)
I didn't hear any news yet, I think in the holidays all major ICT breaktroughs come to a stop.
I mean, also asus never fixed any DNS servers, the last firmware they brought out is from februari...
I'm trying to find out more about the wireless chip of my router.
it appears to have an output of 280mW on wireless N according to the FFC
the normal G has only an output of 120mW or so... and that on the same chip, channel and antenna lol:p

28-07-2008, 19:31
I see this on more rf chips, the OFDM has his own curious way to do things :)