802.11G signal "stronger" than B?

K

KevC

Supreme [H]ardness
Joined
Oct 21, 2001
Messages
6,365
Hey,

I currently have my computer in the basement. My router (linksys 802.11b wifi) and cable modem is upstairs. Basically it is seperated by 2 floors.

I want to stream ALAC through iTunes to my laptop (since it is hooked up to my mid/hi-fi system) to play in my room. However, recently it's been having a little bit of issues. Always buffering. Really annoying :(

I don't think it's the bandwidth issue, cos 802.11B should be able to stream a 40MB 6minute song. (that's only 111kb/s).

It's probably a signal strength issue, as it is always "low" on my desktop in the basement.

Should I "upgrade" to wifi-G? Are there ways to improve signal strength? I don't see any way to move the computer closer to the router.
 
As a general rule, G offers more bandwidth, but B has longer range.
Getting a bigger antenna for the AP might help.
My advice though would be call your ISP, and have them send someone over to relocate the modem to the basement. Will cost you all of like 20 bucks, and you wont have to keep dealing with lack of reliability from the wireless connection.
 
B travels better through walls and obstacles.
G offers faster speeds and better throughput.
 
Malk-a-mite said:
Last I checked - the spec has them both at 100' (indoors)
Click to expand...

Same here. IIRC its 100M indoors and something like 400M outdoors.
 
Quick answer, B goes a tad further.

Long answer, it depends.

B does well for long range shots, most people seem to use B for point to point over several miles.

G, OFDM, does better with multipath. 200ft away in my dad's shop, metal walls, roof, etc, B doesn't work, but G does. Out in the yard, walking down the road, etc, B goes a bit further. Behind the trees, G does better.
 
B does NOT travel farther than .11g. Period.

Both 2.4 Ghz signals. Propogate at the same rate. What does matter is power to the antenna and the antenna themselves. You also have certain software mechanisms in place on both sides of the link that can help level out noise. General quality of the radio's etc.. But the idea that a .11b signal travels farther than a .11g signal is fallacious at best, and silly at worst.

OP, if range is an issue there are several things you can do including AP placement, power boost, antenna polarization and angle. If upgrading is your choice then MIMO technologies do typically offer better range in general. Pre-N stuff as well though understand the Pre-N stuff is not guaranteed to be compliant once the spec is ratified, especially since IEEE is struggling with some serious issues in regards to ratification. Probably won't be finalized until late next year if not 08.

As mentioned, OFDM modulation (.11g) can be a better fit where multiple obstructions are concerned.

As far as the "advertised" distances.......are you guys kidding? Marketing fellas.
 
I agree, advertised distance is BS, but I speak from personal experience.

In open areas, I can get a G connection up to about -89dB, B will go to -93dB.

I've done some serious testing, multipath is not an issue during some of these tests, exact same power levels, radios, the only config change was between mixed, where B was possible, and G only.

With G forced, -89 to -90dB, with -96 noise, is 1-2mb absolute limit (not G spec speeds, but still forcing OFDM).

With mixed and watching it swap to B mode, I can get a more reliable signal at -93dB with the same noise levels. 3dB = twice the signal.

Both propogate at the same rate, you are 100% correct, the difference is in the radio's minimum SNR for each and signalling. OFDM is better at correcting for smaller errors, DSSS signal is a little more peaky, the center carrier seems to be a bit more powerful, where OFDM is spread pretty flat. Couple that with 11b needs about 6dB SNR, 11g is recommended 20dB SNR minimum...
 
Oldman - what equipment are you using. I klnow some Cisco will only let you go up to 30Mw for G (OFDM) and 100Mw for B (CCK)

wap2(config-if)#power local cck ?
<1 - 100> One of: 1 5 10 20 30 50 100
maximum Set local power to allowed maximum

wap2(config-if)#power local cck


wap2(config-if)#power local ofdm ?
<1 - 30> One of: 1 5 10 20 30
maximum Set local power to allowed maximum

wap2(config-if)#power local ofdm
 
WRT54GL with DD-WRT.

My understanding is the power is stronger at the sidebands, that is why Ciso only allows 30mw for OFDM, but its still under the legal limit by a good margin. I don't know why they do it. 11b sidebands are weaker, less prone to interfere. That is also why Cisco recommended using channels 1, 4, 8 and 11 with B. They recommend 1, 6 and 11 with G.
 
You must log in or register to reply here.
Back
Top