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Right now I'm using wavemon to look at wifi networks in the area, but it doesn't matter what tool I use: The signal strengths of every wifi network I can see are always identical to each other. They change over time but they never differ from each other. I can't imagine this is correct because that doesn't seem to make sense to me physically.

For example:

enter image description here

It doesn't matter what tool I use:

$ sudo iwlist wlan0 scanning | grep 'level\|Address'
Cell 01 - Address: 84:1B:5E:E9:C9:D3
          Quality=66/70  Signal level=-44 dBm  
Cell 02 - Address: 86:1B:5E:E9:C9:D4
          Quality=66/70  Signal level=-44 dBm  
Cell 03 - Address: 00:22:75:98:A6:6D
          Quality=66/70  Signal level=-44 dBm  
Cell 04 - Address: F8:E4:FB:D8:B9:ED
          Quality=66/70  Signal level=-44 dBm  
Cell 05 - Address: 00:1B:2F:01:DD:04
          Quality=66/70  Signal level=-44 dBm

I know where the radios for these networks are physically located and the signal strengths should not be identical.

What is the source of this information and why is this happening?

I am using Ubuntu 12.04 LTS:

$ uname -rvm
3.2.0-64-generic #97-Ubuntu SMP Wed Jun 4 22:03:48 UTC 2014 i686
$ lspci | grep -i wifi
03:00.0 Network controller: Realtek Semiconductor Co., Ltd. \
        RTL8188CE 802.11b/g/n WiFi Adapter (rev 01)
$ lsmod | grep rtl
rtl8192ce              75529  0 
rtl8192c_common        69519  1 rtl8192ce
rtlwifi                95855  1 rtl8192ce
mac80211              436493  3 rtl8192ce,rtl8192c_common,rtlwifi
cfg80211              178877  2 rtlwifi,mac80211

Update: On Windows 7, 64-bit, on the same machine (dual booted), inSSIDer reports differing (and reasonable) signal strengths for the networks in the area; this at least rules out the hardware itself. I have not tried other Linux distributions yet. I have not tried FreedomBen's driver yet either.

Jason C
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  • The most likely reason for this is that the software cannot get accurate information from your wifi hardware. To verify that it is not just a fluke with your installation, I suggest trying the same test with LiveCD of a different Linux distribution. – Rucent88 Jul 17 '14 at 22:38
  • @Rucent88 A few minutes ago, I confirmed that inSSIDer, on Windows, on the same machine (dual boot) does show differing (and reasonable) signal strengths for the networks in the area. So I at least know it is not the hardware itself. I will try other Linux distributions as soon as I can. – Jason C Jul 17 '14 at 22:43
  • @Jason C, this seems most likely to be an issue with wavemon. Check the signal strength with a separate utility (e.g., iwlist) to see if it is system-wide or per-application. – HalosGhost Jul 18 '14 at 05:39
  • @HalosGhost iwlist has the same issue. – Jason C Jul 18 '14 at 05:53

1 Answers1

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Try going to www.realtek.com and searching for an updated driver (kernel module) for your chipset. I have an 8192 set in my notebook (Kubuntu Precise 12.04 with backports) and it had very poor wifi signal strength until I installed the custom module. (It's still not great, but it's much better than it was.)

I think the one you want is the same as mine and it's here, but please do your own checking. (Finding stuff on their website is not that easy.)

http://218.210.127.131/downloads/downloadsView.aspx?Langid=1&PNid=21&PFid=48&Level=5&Conn=4&DownTypeID=3&GetDown=false&Downloads=true#2722

Once you find the right one, you download the tarball and expand it in a folder where you keep custom software. Then, in that folder, you run

make
sudo make install

I don't think this works instantly. You may have to do something like one or more insmod commands (There are several modified modules and I'm not too conversant with activating kernel modules on the fly.), but it will definitely be there working after you reboot.

The only thing to watch out for is that kernel modules are built to match an exact kernel version, so every time you install a kernel update from your package manager, etc., you need to do the make/sudo make install again so everything lines up.

Joe
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