openwifi/doc/app_notes/ap-client-two-sdr.md
2021-02-03 15:30:40 +01:00

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  • Power on two SDR boards. Call one board "AP board" and the other "client board". On each board, the TX and RX antenna should vertical/orthogonal to each other as much as possible to gain a good TX/RX isolation.

  • Connect a computer to the AP board via Ethernet cable. The computer should have static IP 192.168.10.1. Open a terminal on the computer, and then in the terminal:

    ssh root@192.168.10.122
    (password: openwifi)
    cd openwifi
    ./fosdem.sh
    (It will create a WiFi AP by hostapd program with config file: hostapd-openwifi.conf)
    (Wait for the script completed)
    cat /proc/interrupts
    (Execute the "cat ..." command for several times)
    (You should see the number of "sdr,tx_itrpt1" grows, because it sends the "openwifi" beacon periodically)
    
  • Connect another computer to the client board via Ethernet cable. The computer should have static IP 192.168.10.1. Open a terminal on the computer, and then in the terminal:

    ssh root@192.168.10.122
    (password: openwifi)
    service network-manager stop
    cd openwifi
    ./wgd.sh
    (Wait for the script completed)
    ifconfig sdr0 up
    iwlist sdr0 scan
    (The "openwifi" AP should be listed in the scanning results)
    iwconfig sdr0 essid openwifi
    
  • Now the client is trying to associate with the AP. The AP board terminal should print like:

    ...
    sdr0: AP-STA-CONNECTED 66:55:44:33:22:58
    sdr0: STA 66:55:44:33:22:58 RADIUS: starting accounting session 1FF1C1B4-00000001
    

    If not, please adjust antenna/distance and re-run the commands on the client side.

  • After association is done, in the terminal of client:

    dhclient sdr0
    (Wait for it completed)
    ifconfig sdr0
    (Now you should see the IP address like 192.168.13.x allocated by AP)
    ./set_csma_normal.sh
    ping 192.168.13.1
    (Ping the AP)
    

    Now the communication link should be already setup between the AP and the client.