Like every other website on the planet, SmallNetBuilder uses cookies. Our cookies track login status, but we only allow admins to log in anyway, so those don't apply to you. Any other cookies you pick up during your visit come from advertisers, which we don't control.
If you continue to use the site, you agree to tolerate our use of cookies. Thank you!

Router Charts

Click for Router Charts

Router Ranker

Click for Router Ranker

NAS Charts

Click for NAS Charts

NAS Ranker

Click for NAS Ranker

More Tools

Click for More Tools

Wireless Features

Real-world 11g overlap

Both Atheros and Broadcom were kind enough to supply spectrum analyzer screen shots that will help show what real 802.11g signals look like.

Real Channel 1, 6, 11 802.11g signals (from Atheros)

Figure 4: Real Channel 1, 6, 11 802.11g signals (from Atheros)

Figure 4 shows an composite spectrum analyzer screen shot, supplied by Atheros, of 802.11g signals for the "non-overlapping" channels 1, 6 and 11, with 20MHz channel boundaries marked on the shot for reference. The shapes of the signals look different from those shown in Figure 3 because filtering is applied in the WLAN devices to shape the signal. But you can clearly see that power from each channel's signal overlaps into each other's.

Also notice that each channel's signal is down about 30dB (1/1000) from its peak level by the time it overlaps into the next closest signal. With current radio design technology, this means the overlapping signal has little effect on the primary (i.e. desired) channel.

Real Channel 6 802.11g signal (from Broadcom)

Figure 5: Real Channel 6 802.11g signal (from Broadcom)

So that I don't get accused of playing favorites, Figure 5 shows a similar spectrum analyzer screen shot supplied by Broadcom. Only channel 6 is shown and the top 20dB of channel 1 and 11's signals are drawn in for reference.

The point of this whole exercise has been to make a simple point:

Key Point #1: Normal "non-overlapping" 802.11b and 11g channel 1, 6, and 11 signals do overlap.

So if normal 802.11b / g signals overlap, i.e. interfere with each other, what's the big deal about Super-G's signal doing the same thing? The issue the amount of overlap.

More Wireless

Wi-Fi System Tools
Check out our Wi-Fi System Charts, Ranker and Finder!

Support Us!

If you like what we do and want to thank us, just buy something on Amazon. We'll get a small commission on anything you buy. Thanks!

Over In The Forums

Hi There,Update 2020/08/06386 rc2-3 firmware is in this link
I plan to make available a beta version of the next kamoj add-on - if there is enough interest.N.B: Voxel firmware is a pre-requisite, not an option!I...
I was doing some research and was seeing a lot about issues with the 2.4ghz band not working after a while or having very short range (or poor perform...
No matter what I put for upload/download bandwidth on a new RT-AX88U on Merlin 384.18, it will peg the upload speed at my ISP's maximum speed and ping...
Hi to all!I just installed Pyload and Transmission on my RT-AC86U. Now I have a problem. I have to set the router ( to go to Internet thro...

Don't Miss These

  • 1
  • 2
  • 3