Morero oa OpenWifi ka ts'ebetsong ea chip e bulehileng ea Wi-Fi e thehiloeng ho FPGA le SDR

Kopanong ea ho qetela ea FOSDEM 2020 hlahisoa morero openwifi, ho hlahisa ts'ebetsong ea pele e bulehileng ea stack e feletseng ea Wi-Fi 802.11a/g/n, sebōpeho sa pontšo le modulation eo ho eona ho boletsoeng ho software (SDR, Software Defined Radio). OpenWifi e u lumella ho theha ts'ebetsong e laoloang ka botlalo ea likarolo tsohle tsa sesebelisoa se se nang mohala, ho kenyeletsoa likarolo tse tlase, tseo ho li-adapter tse tloaelehileng tse se nang mohala li kengoang maemong a li-chips tse sa hlahlojoeng. Khoutu likarolo tsa software, hammoho le litšoantšo le litlhaloso li-block blocks ka puo ea Verilog bakeng sa FPGA li ajoa tlasa laesense ea AGPLv3.

Karolo ea hardware ea prototype e sebetsang e bontšitsoeng e thehiloe ho Xilinx Zynq FPGA le AD9361 universal transceiver (RF). OpenWifi e sebelisa meralo ea SoftMAC, e bolelang ho kenya ts'ebetsong ea "wireless stack" ea 802.11 (e phahameng-MAC) ka lehlakoreng la mokhanni le ho ba teng ha lera le tlaase la MAC ka lehlakoreng la FPGA. The wireless stack e sebelisa mac80211 subsystem e fanoeng ke Linux kernel. Tšebelisano le SDR e etsoa ka mokhanni ea khethehileng.

Lintlha tsa bohlokoa:

• Tšehetso e feletseng bakeng sa 802.11a/g le tšehetso e sa fellang bakeng sa 802.11n MCS 0~7 (PHY rx feela hajoale). Ho na le merero ea ho tšehetsa 802.11ax;
• Bandwidth 20MHz le lebelo la maqhubu ho tloha ho 70 MHz ho ea ho 6 GHz;
• Mekhoa sebetsa: Ea tlas'a maemo (marang-rang a lisebelisoa tsa bareki), sebaka sa ho fihlella, seteishene le ho beha leihlo;
• Ts'ebetsong ea protocol ea layer layer ka lehlakoreng la FPGA DCF (Distributed Coordination Function), ho sebelisa mokhoa oa CSMA/CA. E fana ka nako ea ts'ebetso ea foreimi (SIFS) boemong ba 10us;
• Mekhahlelo ea mantlha ea phihlello ea kanale: Nako ea RTS/CTS, CTS-to-self, SIFS, DIFS, xIFS, slot-time, joalo-joalo.
• Ho khaola nako (Ho khaola nako) e thehiloeng ho aterese ea MAC;
• Li-bandwidth le maqhubu a fetohang habonolo:
  2MHz bakeng sa 802.11ah le 10MHz bakeng sa 802.11p;

Hona joale, OpenWifi e fana ka tšehetso Li-platform tsa SDR tse thehiloeng ho FPGA
Xilinx ZC706 e nang le li-transceivers tsa Analog FMCOMMS2/3/4, hammoho le liphutheloana (FPGA + RF) ADRV9361Z7035 SOM + ADRV1CRR-BOB le ADRV9361Z7035 SOM + ADRV1CRR-FMC. E etselitsoe ho kenya setšoantšo se felileng ARM Linux e thehiloeng likarete tsa SD. Ho na le merero ea ho tšehetsa ADRV9364Z7020 SOM + ADRV1CRR-BOB, Xilinx zed + FMCOMMS2/3/4, Xilinx ZCU102 + FMCOMMS2/3/4 le
Xilinx ZCU102 + ADRV9371. Litsenyehelo tsa likarolo tse amehang prototype ea pele ea OpenWifi e ne e ka ba li-euro tse 1300, empa ho tsamaisa liboto tse theko e tlaase ho ntse ho tsoela pele. Ka mohlala, litšenyehelo tsa tharollo e thehiloeng ho Lisebelisoa tsa Analog ADRV9364-Z7020 e tla ba li-euro tse 700, le motheong ZYNQ NH7020 - li-euro tse 400.

Ho lekola tšebetso ea ho hokela moreki ka adaptara ea USB ea TL-WDN4200 N900 sebakeng sa phihlello se thehiloeng ho OpenWifi ho re lumelletse ho fihlela 30.6Mbps (TCP) le 38.8Mbps (UDP) ha re fetisetsa data ho tsoa sebakeng sa phihlello ho ea ho moreki le 17.0Mbps (TCP) le 21.5Mbps (UDP) ha e fetisoa ho tloha ho mofani ho ea sebakeng sa ho fihlella. Bakeng sa tsamaiso, lisebelisoa tse tloaelehileng tsa Linux li ka sebelisoa, tse kang ifconfig le iwconfig, hammoho le lisebelisoa tse khethehileng tsa sdrctl, tse sebetsang ka netlink 'me li u lumella ho laola ts'ebetso ea SDR boemong bo tlaase (ho sebelisa li-regista, fetola li-setting tsa nako, joalo-joalo).

Har'a merero e meng e bulehileng e lekang ka stack ea Wi-Fi, re ka hlokomela morero ona WimeHo theha IEEE 802.11 a/g/p e tsamaellanang fetisang e thehiloe ho GNU Radio le PC e tloaelehileng. Lisebelisoa tsa software tse bulehileng tsa 802.11 le tsona li ntse li nts'etsapele merero Ziria и Sora (Microsoft Research Software Radio).

Source: opennet.ru