This repository includes Linux driver and software. [openwifi-hw](https://github.com/open-sdr/openwifi-hw) repository has the FPGA design. [[Project document](https://github.com/open-sdr/openwifi/tree/master/doc)]
[Demo [video](https://youtu.be/NpjEaszd5u4) and video [download](https://users.ugent.be/~xjiao/openwifi-low-aac.mp4)] [openwifi [maillist](https://lists.ugent.be/wws/subscribe/openwifi)] [[Cite openwifi project](#cite-openwifi-project)]
Openwifi code has dual licenses. AGPLv3 is the opensource license. For non-opensource license, please contact Filip.Louagie@UGent.be. Openwifi project also leverages some 3rd party modules. It is user's duty to check and follow licenses of those modules according to the purpose/usage. You can find [an example explanation from Analog Devices](https://github.com/analogdevicesinc/hdl/blob/master/LICENSE) for this compound license conditions. [[How to contribute]](https://github.com/open-sdr/openwifi/blob/master/CONTRIBUTING.md).
* Don't have any boards? Or you like JTAG boot instead of SD card? Check our test bed [w-iLab.t](https://doc.ilabt.imec.be/ilabt/wilab/tutorials/openwifi.html) tutorial.
* Download pre-built [openwifi Linux .img.xz file](https://users.ugent.be/~xjiao/) (It might not have the latest bug-fixes/features. Check related sections on how to udpate files in img if needed). Burn the img file to a SD card.
* Connect RX/TX antenna to RX1A/TX2A ports(For fmcomms4/ad9364, you may connect antennas to TXA/RXA), and make two antennas orthogonal to each other for good isolation. Config the board to SD card boot mode by switches (Read the board spec on internet). Insert the SD card to the board.
* ***Note***: If openwifi stops working after ~2 hours, it means the evaluation license of Xilinx Viterbi decoder has expired. You need to power cycle the board. Run this command several times on board to confirm:
root@analog:~/openwifi# ./sdrctl dev sdr0 get reg rx 20
SENDaddr: 00040050
reg val: 34be0123
(If the last number of reg val is always 3, that means the Viterbi decoder stops working)
**Build openwifi Linux img based on openwifi FPGA and driver:**
* Download [2017_R1-2018_01_29.img.xz](http://swdownloads.analog.com/cse/2017_R1-2018_01_29.img.xz) from [Analog Devices Wiki](https://wiki.analog.com/resources/tools-software/linux-software/zynq_images). Burn it into a SD card via your PC.
* Mount SD card BOOT/rootfs partitions to SDCARD_DIR directory of your PC (If it is mounted automatically, find the directory). Then copy built files to SD card via your PC. (You can also update files over ftp/ssh after your full system runs. Please check next section. Read carefully user_space/sdcard_boot_update.sh and set your ftp root directory to $OPENWIFI_DIR in your PC):
(Above rule will auto-rename wlan0 to sdr0 which is the openwifi NIC name)
cd $SDCARD_DIR/rootfs
sync
```
**Run Linux and do some post-config:**
* Insert the SD card to the board, power on and run serial console (such as minicom) from a PC via USB-UART cable to the board. After booting completes, in the PC serial console:
* Option 1: Access the board disk/rootfs from Ubuntu PC: "File manager --> Connect to Server...", input: sftp://root@192.168.10.122/root . Then you can operate files on board like normal files on your disk. To update files that need to be in boot partition (BOOT.BIN, uImage and devicetree.dtb), you can transfer those files to rootfs firstly, then on board:
* Option 2: Setup [ftp server](https://help.ubuntu.com/lts/serverguide/ftp-server.html) on PC, allow anonymous and change ftp root directory to $OPENWIFI_DIR. Then on board:
Openwifi only applies OFDM as its modulation scheme and as a result, it is not backward compatible with 802.11b clients or modes of operation. This is usually the case during beacon transmission, connection establishment, and robust communication.
As a solution to this problem, openwifi can be fully controlled only if communicating with APs/clients instantiated using hostapd/wpa_supplicant userspace programs respectively.
For hostapd program, 802.11b rates can be suppressed using configuration commands (i.e. supported_rates, basic_rates) and an example configuration file is provided (i.e. hostapd-openwifi.conf). One small caveat to this one comes from fullMAC Wi-Fi cards as they must implement the *NL80211_TXRATE_LEGACY* NetLink handler at the device driver level.
On the other hand, the wpa_supplicant program on the client side (commercial Wi-Fi dongle/board) cannot suppress 802.11b rates out of the box in 2.4GHz band, so there will be an issue when connecting openwifi (OFDM only). A patched wpa_supplicant should be used at the client side.
