WiFi Channel identification

There are numerous wi-fi channels in use near me. I have set my BT Homehub 3 to auto select the channel but frequently have to manually reset it which may be because of interference. I would like to be able to see what other channels are in use near me.
Neither Linux nor Win Vista network settings show the channels in use.
What app would you advise?

thanks

Inssider

Or NetStumbler. I use the Mac version (iStumbler)

In reply to a post by BatBoy:

Inssider

or to use the correct format:

inSSIDer

Most things that cause issues can't be seen

Scenario A
2 routers on the same channels - normally ok

Scenario B
A router, 3 cordless doorbells, a wireless tv sender, a baby monitor and a few wireless keyboards all on the same channel - this is mayhem

Inssider only shows the routers so you would choose scenario B even though its actually worse than scenario A. As inssider would make scenario Bs channel look less crowded

You often find routers all go on the same channel. Often as its the one less crowded in reality.

Doorbells etc are the things that cause major wireless issues not routers. They're often not very kind in the way they operate compared to routers & can easily make a wireless channel unusable. Multiple routers are much less likely to do this.

It's what you don't see that you need to be worrying about.

Edited by ukhardy07 (Thu 27-Jun-13 15:41:07)

Netstumbler runs in both Windows and Linux (Wine) but won't recognise my Atheros AR500 in Windows - the Atheros is visible but greyed out. On Linux machine it reports "no wireless adaptor found".
Anything I can do about this?

Can't help I'm afraid, I'm exclusively Mac here- the only reason I've even heard of NetStumbler is because of iStumbler.

iwlist eth1 scan

should list APs it can see, with appropriate interface specified where eth1 is indicated

as sudo or root it actively scans, otherwise you get a residual result.

Edited by yarwell (Sun 30-Jun-13 22:05:09)

sudo iwlist eth1 scan

returns:
Interface doesn't support scanning

Check the WiSpy add-on for inSSIDer.

Inssider will do it on it's own.

I have used (Free) inSSIDer for several years now, both Version 2 and Version 3 (the latter to a lesser degree).

Both versions only show working WiFi channels - they do NOT do the Spectrum Analysis required for NON-WiFi Transmissions.

My understanding from the metageek site, is that WiSpy H/W and S/W adds the Spectrum Analysis ability, showing all signals and noise occurring in the WiFi band.

From the metageek site-

http://www.metageek.net/products/wi-spy/
"
Wi-Fi uses the same frequencies as wireless consumer electronics.
In its most basic form, Wi-Fi is radio waves that travel in the 2.4 GHz or 5 GHz bands. When two devices transmit simultaneously, their waves cancel each other out. These collisions are undetected by Wi-Fi cards, but the resulting network slowness or complete loss of connectivity is painfully obvious to humans.
"

Very interesting. However, if you look at the subject and refer to the original post, what he wants to do is " I would like to be able to see what other channels are in use near me." and Inssider does that.

Can anyone here tell me if NetStumbler or inSSIDer need a dedicated Wi-Fi card in order to be able to use.
Or will these apps be able to use my Technicolor TG584n router as the Wireless adapter.

I tried to use inSSIDer before but no adapter was found problem. I'm on Windows 8 based machine.

Edited by majika2007 (Mon 01-Jul-13 13:56:25)

inSSIDer will use the wireless adapter in your PC - if you do not have one it will not work.

Inssider finds my Intel WiFi Link 5100 AGN card, but Netstumbler doesn't.

Evening Batboy

Although the OP did not mention other problem sources; ukhardy07 did introduce such aspects in his-
"
Scenario B
A router, 3 cordless doorbells, a wireless tv sender, a baby monitor and a few wireless keyboards all on the same channel - this is mayhem
"
As stated by others, these can all cause interference - BUT are not identified by inSSIDer in any manner, although inSSIDer and the PC WiFi Rx may be adversely affected; nor if narrow the location of the interfering signal/s or noise within the WiFi spectrum.

So using inSSIDer alone, he may be moving his router to a channel which is APPARENTLY clear; but is actually saturated with non-WiFi noise.

Hence the need for a Spectrum Analyser - which I fully acknowledge is an expensive solution; and may NOT necessarily provide a solution, as the interfering sources are likely to be spread widely over the "WiFi" band.

I'm sure you will agree that generally there is no easy, simple solution in domestic situations, other than resorting to Ethernet cable, there-by defeating the object of having WiFi; or allowing the Router to "Auto-change" the WiFi channel/s in the hope that it can find a suitable channel.

No, I find it easy to use Inssider to find an uncongested channel and set the router to that. Works for me, which is why I recommended it to the OP.

By the time one has gone to the effort of a spectrum analyser it would be easier to set channel to 1, do a speedtest (file transfer between wireless laptop and a PC plugged into GigE) on a laptop in various points in the house, set to channel 6, do the same again, and finally channel 11.

In reply to a post by deniscampbell:

sudo iwlist eth1 scan

returns:
Interface doesn't support scanning

i assume eth1 is your wireless card or you changed it accordingly ?

iwconfig will list interfaces with wireless extensions

iwconfig returns:

wlan0 and details of my router
lo no wireless extensions
eth0 no wireless connections

Agreed in practical terms that this "try it and see" method is the only realistic way for the majority to make any progress; AND if such progress and improvement is even possible.

The only alternatives that I am aware of, is to let the router auto-switch and/or directional aerials and/or relative positioning of router and WiFi PC.

The best WiFi channel may vary on an almost continuous basis, remembering the effects that pulley/weight driven tall clocks could have on the early TV transmissions around 50 MHz and 180 MHz.

Unfortunately, most WiFi users are unaware of all the other devices using the 2.5 GHz Band; and the WiFi monitors present such as inSSIDer only show the detected WiFi signals in a very cleaned-up manner, as though there is nothing else using that part of the spectrum.

Then the radiated power levels of WiFi are extremely low; and the assembies very small - one I have to hand is 5 cm long by 3 cm wide by 4 mm (milli-metres) deep. A lot of that is screening and the basic PCB, so the active components must be almost microscopic.

sudo iwlist wlan0 scan

if it doesn't work then the card or driver doesn't support it, seems odd but we tried.