0

I'm using an Edimax EW-7811Un 802.11b/g/n WiFi adaptor on my RPi model B. It works well.

I am doing some coexistence testing that requires me to run the WiFi in the 802.11b/g 2.4GHz band rather than in the 802.11n 5Ghz band.

  1. How do I discover what channel the Edimax is running on?
  2. How can I force it to run in 11b/g mode (2.4GHz) rather than 11n (5GHz)?

Note: I don't have admin access to my WiFi router, so queries and configuration must be performed on the RPi, not the router.

Update: For reference, here's the results of lsusb:

$ lsusb
Bus 001 Device 002: ID 0424:9512 Standard Microsystems Corp. 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 003: ID 0424:ec00 Standard Microsystems Corp. 
Bus 001 Device 004: ID 7392:7811 Edimax Technology Co., Ltd EW-7811Un 802.11n Wireless Adapter [Realtek RTL8188CUS]
Bus 001 Device 005: ID 0403:8a28 Future Technology Devices International, Ltd Rainforest Automation ZigBee Controller
|improve this question
  • I wouldn't change the channel from the receiver (or pi) unless you are using an ad-hoc network. If you are using a Router, then the router is where you want to adjust the channel. Clients talking to the router (such as the Pi) should adjust channel on connection. – Tyson Feb 14 '15 at 1:57
1

1) You can use the command iwlist channel to find the channel.

2) No idea, I suggest you look at iwconfig.

|improve this answer
4

iwconfig describes the state of the WiFi adaptor, and can modify it as well:

# iwconfig
wlan0     IEEE 802.11bg  ESSID:"pichincha"  Nickname:"<WIFI@REALTEK>"
          Mode:Managed  Frequency:2.437 GHz  Access Point: 00:25:9C:6B:1D:25   
          Bit Rate:54 Mb/s   Sensitivity:0/0  
          Retry:off   RTS thr:off   Fragment thr:off
          Encryption key:****-****-****-****-****-****-****-****   Security mode:open
          Power Management:off
          Link Quality=100/100  Signal level=100/100  Noise level=0/100
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

lo        no wireless extensions.

eth0      no wireless extensions.

iwfcofig can also be used to set the channel, as in:

# iwconfig wlan0 channel 3

I haven't tried that, but that's what man iwconfig suggests.

|improve this answer

protected by Ghanima♦ Apr 23 '17 at 21:44

Thank you for your interest in this question. Because it has attracted low-quality or spam answers that had to be removed, posting an answer now requires 10 reputation on this site (the association bonus does not count).

Would you like to answer one of these unanswered questions instead?

Not the answer you're looking for? Browse other questions tagged or ask your own question.