Ukurekhoda i-ultra-wideband 802.15.4 imiqondiso ye-UWB kwisixhobo esiphantse savunywa

Kutshanje, amazwe amabini ehlabathi ahluke ngokupheleleyo adibene kwilebhu yethu: ilizwe lee-transceivers zikanomathotholo ezingabizi kakhulu kunye nelizwe leenkqubo ezibiza imali eninzi zokurekhoda imiqondiso yerediyo yerediyo.

Okokuqala, abahlobo bethu abalungileyo basondela kuthi ukwenza isoftware yokurekhoda umqondiso kunye nebhendi ye-500 MHz. Kakade ke, sasingenakwala. Emva koko, kwakuyimfuneko ukwenza oku kwibhodi evela kwinkampani "Instrumental Systems", endiyazi ixesha elide. Ekuqaleni komsebenzi wam wobunjineli, kwafuneka ndisebenze ngehardware kunye nesoftware yabo.

Kwaye kwafika umhlobo wam endimthandayo mikkab из Umboniso weDrone kwaye ucele ukwenza inkqubo yokubeka iidrones ngaphandle kweGPS. Kuyimfuneko, utsho, ukusungula umboniso ngaphakathi. Kwaye kule mihla, esitratweni, awufuni nyani ukuzisa izigidi zeedola esibhakabhakeni ngeGPS engathembekanga. Ukuphazamiseka kokuhamba kwe-Sat kunye ne-spoofing bayachuma.

Ukubeka indawo ngaphandle kweesathelayithi ngokuchaneka okungcono kuneesentimitha ezilishumi kwindawo ukuya kuthi ga kwikhilomitha, andifumananga nto yimbi ngaphandle kwetekhnoloji ye-UWB. I-DecaWave sele ikwimarike ixesha elide, ivelisa i-chip ye-DW1000 kunye neemodyuli ezisekelwe kuyo. I-chip ngumgangatho we-UWB we-transceiver we-IEEE 802.15.4-2011. Ngendlela, le nto iyingqayizivele, kunye nezantsi kabini okanye kathathu. Ndiyathemba ukuba singakwazi ukuthoba ubunzulu bayo kwiminyaka embalwa ezayo kwaye sibhale ngayo. Ngokuqinisekileyo awuyi kukwazi ukuyenza kwangaphambili.

Kodwa namhlanje asithethi ngokubeka; siza kuthetha ngaloo nto kuthotho olulandelayo.

Namhlanje sirekhoda uphawu lwe-DW1000. Kwaye i-bandwidth yalo mqondiso ayikho ngaphezulu okanye ngaphantsi, kodwa i-1000 okanye i-500 MHz, egqitywe yinombolo yetshaneli. "Ngokupheleleyo ngengozi" kwakukho ikhompyutha kunye nebhodi yesiphaluka kwitafile elandelayo I-FMC126P ukusuka "Iinstrumental Systems" kunye FMC mezzanine AD9208-3000EBZ ukusuka kwizixhobo ze-Analog.

Kufuneka kuqatshelwe apha "kumtshutshisi" ukuba i-AD9208 ADC iteknoloji evunyiweyo namhlanje. Awukwazi ukuyithenga ngokusemthethweni eRashiya, nangona ngamanye amaxesha ufuna ngokwenene. Kodwa le modyuli ithile yathengwa kwakudala kakhulu, xa kwakungekabikho izohlwayo. Unyulu, njengomphefumlo wosana. Ndiyathemba ukuba esi sivumo siya kufakwa kunye netyala kwaye siya kufakwa kummangalelwa.

Asiyi kungena kwiinkcukacha zokuphuhlisa isoftware yokurekhoda uthotho lokufundwa kwimemori yekhompyutha okwangoku. Ngelishwa, asinakukwazi ukupapasha ikhowudi yomthombo wesicelo okwangoku. LinuxKodwa sinethemba lokufumana imvume yoku kwixesha elizayo. Kubalulekile ukuqaphela ukuba bekungelula, nangona kukho uphuhliso lwesoftware olubonelelwe yi-Instrumented Systems. I-ADC ngokwayo kunye nenkqubo yayo yokuqhobosha kunye nesampulu yemveliso esebenzisa ubuchwepheshe be-JESD204B zinzima kakhulu ukuyiqonda, kwaye imodyuli ye-AD ikwafuna ii-hardware patches. Isignali ye-REFCLK ibalulekile kwinkqubo yokufaka, kodwa kwimodyuli, yayiqhagamshelwe kwiipini ezingalunganga zesixhumi se-FMC kwaye, ngenxa yoko, yayingafikeleli kwiipini ezichanekileyo ze-FPGA. Kwakufuneka kufakwe i-patch, onokuyibona kwifoto engezantsi—iintambo ezimbini ezibomvu. Ewe, kwakukho amathandabuzo okuba oku kuya kusebenza. I-frequency yesignali yewotshi iphezulu—375 MHz—kwaye i-patch imbi kakhulu. Kodwa inkqubo ikwazile ukumelana nayo.

Ikhitshi lonke likhangeleka ngolu hlobo.

Apha ungabona ikhomputha enenkqubo ye-I/O elungileyo, ibhodi ye-FMC126P, kunye ne-AD9208-3000EBZ mezzanine. Phakathi kweejeneretha: i-3000 MHz ijeneretha yokuvala i-ADC, i-770 MHz generator ye-REFCLK. Iintambo ezineziqhagamshelo ze-SMA zidibanisa iijeneretha kwaye zinike uphawu lokufaka.

Isantya sedatha eluhlaza ukusuka kwimveliso ye-ADC, ukuba awuyi kungena kwiinkcukacha, yi-12 GB / s ukusuka kumajelo amabini. Ngokwemilinganiselo kwaye ngokutsho komenzi webhodi ye-FMC126P, isantya esiphezulu sokufaka i-5 GB / s. Ngoko ke, sasebenzisa ishaneli enye kuphela kwi-ADC kwaye sadlula kwi-DDC (i-Digital Down Converter) eyakhiwe kwi-AD9208 ngokuchithwa kwezine. Ngaloo ndlela, ukuhamba kwedatha kwakuyi-3 GB / s (i-sampling frequency 750 MHz, i-16-bit isignali eyinkimbinkimbi).

Ukukhangela ukuba inkqubo inexesha lokurekhoda iisampulu kulula kakhulu: ufuna nje ukubeka esweni amasuntswana ancangathi emeko yeFPGA FIFO. Ukuba bekungekho ziganeko zokuPhuphuma kweFIFO ngobusuku nje obunye, intwana ayisayi kumiselwa. Kwaye sichaza ngovuyo ukuba akukho kulahleka kokufunda. Okokuqala sijonga, ngokuqinisekileyo, ukuba i-latching status bits iyasebenza. Sikwajonga imilo yomqondiso kwifayile ukuqinisekisa ukuba umgangatho we-ADC signal efakiweyo uhambelana namaxwebhu.

Kodwa luhlobo luni lwesiginali oluya kulufanelekela inkqubo yokufaka enjalo? Ngokuqinisekileyo i-UWB evela kwitheyibhile elandelayo!

Ngethamsanqa, sikhethe i-4 GHz isitishi sokuphindaphinda kwenkqubo yokumisa idrone. Oku kuhambelana ne-channel 4 kunye ne-2 kwisigama se-DW1000 (Umfanekiso we-13 wedatha yedatha). Senza i-eriyali eyakhelwe ebhodini yale frikhwensi, okanye, ngcono, kolu luhlu. Kwakungekho lula ukuyilungelelanisa phezu kwebhendi ebanzi ngolo hlobo. Kodwa loo nto yajika yaba yinkanuko! Abanye bathi kubonakala ngathi luphawu ... ngeendlebe.

Isiginali ye-4 GHz ene-500 MHz bandwidth iwela ngaphakathi kwebhendi yeNyquist yesithathu kwaye inamathuba aneleyo okugada ukuphepha ukuhlambalaza. Ke ngoko, siqhagamshele nje isiginali ye-DW1000 kwigalelo le-AD9208 ADC ngokuthe ngqo.

Sifumene iifayile ezimbini: enye kunye ne-PRF frequency ye-64 MHz, enye - 16 MHz. Isantya sothumelo simiselwe kubuncinci be-DW1000 - 110 kbit/s.

Oku eyokuqala ifayile, le yesibini. Qaphela, iifayile zinkulu!

Kwifayile yokuqala sibona iipakethi ezihlala malunga neesampuli ze-750 okanye i-nanoseconds eyi-1000.

Kwifayile yesibini, iipakethi zifutshane ngokuphindwe kane.

Kwaye oku kuhambelana ngokupheleleyo nomgangatho we-IEEE 802.15.4-2011 ngokomgangatho womzimba we-UWB:

Ukumodareyitha ngaphakathi kwepakethe kufana nokumodareyitha kwesigaba, esikwahambelana naloo nto ichazwe kumgangatho we-BPSK. Unokufumana umgangatho ngokwawo kwi-Intanethi, khangela "IEEE 802.15.4-2011".

Ukuba ukwandisa kancinane ixesha lokujonga ifestile, ungabona kwakhona ukungalingani kweepakethi, ezihambelana nenkcazo yokumodareyitha hybrid IEEE 802.15.4-2011 UWB - isikhundla-isigaba (BPM-BPSK).

Ngokubanzi, ndifumana i-chip ye-DW1000 kunye nokuguqulwa kwe-UWB PHY ibe yibhomu, nokuba yintoni na loo nto ithetha, into, kwinqanaba le-JTIDS yomkhosi. Le yinto yam entsha yokuzonwabisa. Iza kuqhubeka!

Ngakolunye uhlangothi, siya kukumba i-DW1000, kwelinye, siya kujongana nomgangatho we-IEEE 802.15.4.

umthombo: www.habr.com