OpenWifi project nrog rau kev siv ntawm qhib Wi-Fi nti raws li FPGA thiab SDR

Thaum kawg ntawm FOSDEM 2020 lub rooj sib tham hais tawm peb tes num openwifi, tsim thawj qhib kev siv ntawm tag nrho Wi-Fi 802.11a/g/n pawg, cov teeb liab duab thiab kev hloov kho uas tau teev tseg hauv software (SDR, Software Defined Radio). OpenWifi tso cai rau koj los tsim kom muaj kev tswj xyuas tag nrho ntawm txhua yam khoom ntawm lub wireless ntaus ntawv, suav nrog cov txheej txheem qis, uas nyob rau hauv cov qauv wireless adapters yog siv nyob rau theem ntawm cov chips uas tsis tuaj yeem tshawb xyuas. Code cov khoom siv softwareThiab daim duab thiab piav qhia hardware blocks hauv Verilog lus rau FPGA raug faib raws li daim ntawv tso cai AGPLv3.

Cov khoom siv kho vajtse ntawm cov qauv ua haujlwm tau ua pov thawj yog raws li Xilinx Zynq FPGA thiab AD9361 universal RF transceiver. OpenWifi siv SoftMAC architecture, uas cuam tshuam nrog kev siv lub hauv paus 802.11 wireless stack (high-MAC) ntawm sab tsav tsheb thiab txheej MAC qis ntawm sab FPGA. Lub wireless stack yog muab los ntawm mac80211 kernel subsystem. LinuxKev sib cuam tshuam nrog SDR yog ua tiav los ntawm tus tsav tsheb tshwj xeeb.

Cov yam ntxwv tseem ceeb:

• Kev them nyiaj yug tag nrho rau 802.11a / g thiab kev txhawb nqa ib nrab rau 802.11n MCS 0 ~ 7 (PHY rx nkaus xwb rau tam sim no). Muaj cov phiaj xwm txhawb nqa 802.11ax;
• Bandwidth 20MHz thiab zaus ntawm 70 MHz txog 6 GHz;
• Kev khiav hauj lwm hom: Ad hoc (network ntawm cov neeg siv khoom), chaw nkag, chaw nres tsheb thiab saib xyuas;
• Kev siv cov txheej txheem txuas txuas ntawm FPGA sab DCF (Distributed Coordination Function), siv txoj kev CSMA/CA. Muab lub sijhawm ua cov txheej txheem (SIFS) ntawm qib 10us;
• Configurable channel nkag tau qhov tseem ceeb tsis: RTS / CTS ncua sij hawm, CTS-rau-tus kheej, SIFS, DIFS, xIFS, slot-time, thiab lwm yam.
• Lub sijhawm txiav (Sijhawm hlais) raws li MAC chaw nyob;
• Hloov tau yooj yim bandwidth thiab zaus:
  2MHz rau 802.11ah thiab 10MHz rau 802.11p;

Tam sim no, OpenWifi muab yug FPGA-based SDR platforms
Xilinx ZC706 nrog Analog Devices FMCOMMS2/3/4 transceivers, as Well as bundles (FPGA + RF) ADRV9361Z7035 SOM + ADRV1CRR-BOB thiab ADRV9361Z7035 SOM + ADRV1CRR-FMC. Tsim rau kev thauj khoom daim duab tiav Cov ntawv teev lus SD uas siv ARM LinuxCov phiaj xwm suav nrog kev txhawb nqa rau ADRV9364Z7020 SOM + ADRV1CRR-BOB, Xilinx zed + FMCOMMS2/3/4, Xilinx ZCU102 + FMCOMMS2/3/4 thiab
Xilinx ZCU102 + ADRV9371. Tus nqi ntawm cov khoom koom nrog hauv thawj OpenWifi qauv yog kwv yees li 1300 euros, tab sis kev xa mus rau cov laug cam pheej yig dua tab tom ua. Piv txwv li, tus nqi ntawm kev daws teeb meem raws li Analog Devices ADRV9364-Z7020 yuav yog 700 euros, thiab ntawm lub hauv paus ZYNQ NH7020 - 400 € ib.

Kev sim kev ua haujlwm ntawm kev sib txuas ntawm tus neeg siv khoom nrog TL-WDN4200 N900 USB adapter mus rau qhov chaw nkag OpenWifi tau ua rau muaj 30.6 Mbps (TCP) thiab 38.8 Mbps (UDP) rau kev xa cov ntaub ntawv los ntawm qhov chaw nkag mus rau tus neeg siv khoom, thiab 17.0 Mbps (TCP) thiab 21.5 Mbps (UDP) rau kev xa cov ntaub ntawv los ntawm tus neeg siv khoom mus rau qhov chaw nkag. Cov cuab yeej siv ua ke tuaj yeem siv rau kev tswj hwm. Linux, xws li ifconfig thiab iwconfig, nrog rau cov khoom siv tshwj xeeb sdrctl, uas ua haujlwm ntawm netlink thiab tso cai rau koj tswj hwm kev ua haujlwm SDR ntawm qib qis (tswj cov npe sau npe, hloov cov sijhawm ntsuas, thiab lwm yam).

Ntawm lwm cov haujlwm qhib kev sim nrog Wi-nkaus pawg, peb tuaj yeem nco txog qhov project WimeTxhim kho IEEE 802.11 a/g/p ua raws transmitter raws li GNU Xov tooj cua thiab lub PC tsis tu ncua. Software qhib 802.11 wireless stacks tseem tab tom tsim cov haujlwm Ziria и Sora (Microsoft Research Software Radio).

Tau qhov twg los: opennet.ru