Ungayikhetha kanjani imodemu ye-broadband yemoto yasemoyeni engenamuntu (UAV) noma amarobhothi

Inselele yokudlulisa inani elikhulu ledatha kusuka kumoto wasemoyeni ongaphethwe muntu (i-UAV) noma amarobhothi aphansi ayijwayelekile ezinhlelweni zesimanjemanje. Lesi sihloko sidingida indlela yokukhetha yamamodemu e-broadband nezinkinga ezihlobene. I-athikili ibibhalelwe i-UAV nabathuthukisi berobhothi.

Izindlela Zokukhetha

Imibandela esemqoka yokukhetha imodemu ye-broadband yama-UAV noma amarobhothi yilezi:

1. Ibanga lokuxhumana.
2. Izinga eliphezulu lokudluliswa kwedatha.
3. Ukubambezeleka ekudlulisweni kwedatha.
4. Isisindo nemingcele yobukhulu.
5. Izixhumi ezibonakalayo zolwazi.
6. Izidingo zokudla okunomsoco.
7. Isilawuli esihlukile/isiteshi se-telemetry.

Ibanga lokuxhumana

Ibanga lokuxhumana alincikile kumodemu kuphela, kodwa futhi nasezintanjeni, izintambo zezinti, izimo zokusakaza amaza omsakazo, ukuphazamiseka kwangaphandle nezinye izizathu. Ukuze uhlukanise amapharamitha emodemu ngokwayo kwamanye amapharamitha athinta ububanzi bokuxhumana, cabangela isibalo sobubanzi [Kalinin A.I., Cherenkova E.L. Ukusatshalaliswa kwamaza omsakazo nokusebenza kwezixhumanisi zomsakazo. Ukuxhumana. eMoscow. 1971]

$$display$$ R=frac{3 cdot 10^8}{4 pi F}10^{frac{P_{TXdBm}+G_{TXdB}+L_{TXdB}+G_{RXdB}+L_{RXdB}+ |V|_{dB}-P_{RXdBm}}{20}},$$display$$

kuphi
$inline$R$inline$ - ububanzi bokuxhumana obudingekayo ngamamitha;
$inline$F$inline$ - imvamisa ku-Hz;
$inline$P_{TXdBm}$inline$ — amandla okuthumela imodemu ku-dBm;
$inline$G_{TXdB}$inline$ — inzuzo ye-antenna yokudlulisela ku-dB;
$inline$L_{TXdB}$inline$ — ukulahlekelwa kukhebula kusuka kumodemu kuya othini lokudlulisela ku-dB;
$inline$G_{RXdB}$inline$ — inzuzo ye-antenna ku-dB;
$inline$L_{RXdB}$inline$ — ukulahlekelwa kukhebuli ukusuka kumodemu kuya othini lomamukeli ku-dB;
$inline$P_{RXdBm}$inline$ — ukuzwela kwesamukeli semodemu ku-dBm;
I-$inline$|V|_{dB}$inline$ iyisici sokunciphisa esicabangela ukulahlekelwa okwengeziwe ngenxa yethonya lendawo yoMhlaba, izimila, umkhathi nezinye izici ku-dB.

Kusukela ku-equation yobubanzi kuyacaca ukuthi ububanzi buncike kuphela kumapharamitha amabili emodemu: amandla okudlulisela imali $inline$P_{TXdBm}$inline$ kanye nokuzwela komamukeli $inline$P_{RXdBm}$inline$, noma kunalokho emehlukweni wawo. - isabelomali samandla semodemu

$$display$$B_m=P_{TXdBm}-P_{RXdBm}.$$display$$

Amapharamitha asele esilinganisweni sobubanzi achaza izimo zokusakaza isignali kanye nemingcele yamadivayisi e-antenna-feeder, i.e. ayihlanganise lutho nemodemu.
Ngakho-ke, ukuze ukwandise ububanzi bokuxhumana, udinga ukukhetha imodemu enenani elikhulu le-$inline$B_m$inline$. Ngokulandelayo, i-$inline$B_m$inline$ inganyuswa ngokukhuphula i-$inline$P_{TXdBm}$inline$ noma ngokunciphisa i-$inline$P_{RXdBm}$inline$. Ezimweni eziningi, abathuthukisi be-UAV bafuna imodemu enamandla okudlulisela phambili futhi abanaki kancane ukuzwela komamukeli, nakuba kudingeka benze okuphambene ncamashi. Isidlulisi esinamandla esisebhodini semodemu ye-broadband sihlanganisa lezi zinkinga ezilandelayo:

• ukusetshenziswa kwamandla okuphezulu;
• isidingo sokupholisa;
• ukuwohloka kokuhambisana kwe-electromagnetic (EMC) nezinye izinto ezisebhodini ze-UAV;
• imfihlo yamandla aphansi.

Izinkinga ezimbili zokuqala zihlobene nokuthi izindlela zesimanje zokudlulisa ulwazi oluningi ngesiteshi somsakazo, ngokwesibonelo i-OFDM, zidinga umugqa umthumeli. Ukusebenza kahle kwama-radio transmitter alayini esimanje kuphansi: 10–30%. Ngakho-ke, i-70-90% yamandla ayigugu we-UAV yamandla aguqulwa abe ukushisa, okumele kukhishwe ngokuphumelelayo kwimodemu, ngaphandle kwalokho izohluleka noma amandla ayo okukhiphayo azokwehla ngenxa yokushisa ngokweqile ngesikhathi esingafaneleki kakhulu. Isibonelo, i-transmitter engu-2 W izodonsa u-6–20 W ekunikezeni amandla, lapho u-4–18 W uzoguqulelwa ekushiseni.

I-stealth yamandla yesixhumanisi somsakazo ibalulekile ezinhlelweni ezikhethekile nezempi. Ukwebiwa okuphansi kusho ukuthi isignali yemodemu itholwa ngamathuba aphezulu umamukeli wolwazi wesiteshi sokujama. Ngokuvumelana nalokho, amathuba okucindezela isixhumanisi somsakazo esinamandla aphansi futhi aphezulu.

Ukuzwela kwesamukeli semodemu kubonisa ikhono laso lokukhipha ulwazi kumasiginali atholiwe ngezinga elithile lekhwalithi. Imibandela yekhwalithi ingase yehluke. Kuzinhlelo zokuxhumana zedijithali, amathuba ephutha elincane (izinga lephutha elincane - BER) noma amathuba ephutha ephaketheni lolwazi (izinga lephutha lozimele - FER) lisetshenziswa kakhulu. Empeleni, ukuzwela izinga laso kanye isiginali okufanele kukhishwe kuyo ulwazi. Isibonelo, ukuzwela kuka-−98 dBm nge-BER = 10−6 kubonisa ukuthi ulwazi olune-BER enjalo lungakhishwa kusignali enezinga elingu-−98 dBm noma ngaphezulu, kodwa ulwazi olunezinga, yithi, −99 dBm ngeke zisakhishwa kusignali enezinga, yithi, −1 dBm. Yiqiniso, ukwehla kwekhwalithi njengoba izinga lesignali liyancipha kwenzeka kancane kancane, kodwa kufanelekile ukukhumbula ukuthi amamodemu amaningi esimanje analokho okubizwa. umphumela we-threshold lapho ukwehla kwekhwalithi lapho ileveli yesiginali yehla ngaphansi kokuzwela kwenzeka ngokushesha okukhulu. Kwanele ukunciphisa isignali ngo-2-10 dB ngaphansi kokuzwela kwe-BER ukuze ikhuphuke ibe ngu-1-XNUMX, okusho ukuthi ngeke usayibona ividiyo evela ku-UAV. Umphumela uwumphumela oqondile wethiyori ka-Shannon wesiteshi esinomsindo; ngeke ususwe. Ukucekelwa phansi kolwazi lapho izinga lesiginali lincipha ngaphansi kokuzwela kwenzeka ngenxa yethonya lomsindo owakhiwe ngaphakathi komamukeli uqobo. Umsindo wangaphakathi womamukeli awukwazi ukuqedwa ngokuphelele, kodwa kungenzeka ukunciphisa izinga laso noma ufunde ukukhipha ulwazi ngokuphumelelayo kusignali enomsindo. Abakhiqizi bemodemu basebenzisa zombili lezi zindlela, benza ukuthuthukiswa kwamabhulokhi e-RF yomamukeli futhi bathuthukise ama-algorithms okucubungula isignali yedijithali. Ukuthuthukisa ukuzwela kwesamukeli semodemu akuholeli ekwenyukeni okumangazayo kokusetshenziswa kwamandla kanye nokuchithwa kokushisa njengokwandisa amandla okudlulisela. Yebo, kukhona ukwanda kokusetshenziswa kwamandla kanye nokukhiqizwa kokushisa, kodwa kunesizotha.

I-algorithm elandelayo yokukhetha imodemu iyanconywa ngokombono wokuzuza uhla lokuxhumana oludingekayo.

1. Nquma ngezinga lokudluliswa kwedatha.
2. Khetha imodemu ezwela kakhulu ngesivinini esidingekayo.
3. Nquma ububanzi bokuxhumana ngokubala noma ukuhlola.
4. Uma ububanzi bokuxhumana buba buncane kunesidingo, zama ukusebenzisa lezi zinyathelo ezilandelayo (ezihlelwe ngendlela yokuncipha kokubalulekile):

• nciphisa ukulahlekelwa ezintanjeni ze-antenna $inline$L_{TXdB}$inline$, $inline$L_{RXdB}$inline$ ngokusebenzisa ikhebula elinokuncishwa komugqa ophansi kumafrikhwensi okusebenza kanye/noma ukunciphisa ubude bezintambo;
• khuphula inzuzo ye-antenna $inline$G_{TXdB}$inline$, $inline$G_{RXdB}$inline$;
• khulisa amandla okuthumela imodemu.

Amanani okuzwela ancike kuzinga lokudluliswa kwedatha ngokomthetho: isivinini esiphezulu - ukuzwela okubi kakhulu. Isibonelo, ukuzwela okungu-−98 dBm kokungu-8 Mbps kungcono kunokuzwela okungu-−95 dBm kokungu-12 Mbps. Ungaqhathanisa amamodemu ngokuya ngokuzwela kuphela ngesivinini esifanayo sokudlulisa idatha.

Idatha emandleni okudlulisela cishe itholakala njalo kuzicaciso zemodemu, kodwa idatha yokuzwela komamukeli ayitholakali njalo noma ayanele. Okungenani, lesi yisizathu sokuqapha, njengoba izinombolo ezinhle azinangqondo ukucasha. Ngaphezu kwalokho, ngokungashicileli idatha yokuzwela, umkhiqizi uncisha umthengi ithuba lokulinganisa ububanzi bokuxhumana ngokubala. ukuze ukuthenga imodemu.

Izinga eliphezulu lokudluliswa kwedatha

Ukukhetha imodemu ngokusekelwe kule parameter kulula uma izidingo zejubane zichazwe ngokucacile. Kodwa kukhona ama-nuances athile.

Uma inkinga ixazululwa idinga ukuthi kuqinisekiswe uhla lokuxhumana olusezingeni eliphezulu futhi ngesikhathi esifanayo kuyenzeka ukwaba ibhendi yefrikhwensi ebanzi ngokwanele yesixhumanisi somsakazo, khona-ke kungcono ukukhetha imodemu esekela ibhendi yefrikhwensi ebanzi (bandwidth). Iqiniso liwukuthi isivinini solwazi esidingekayo singafinyelelwa kubhendi yefrikhwensi encane ngokusebenzisa izinhlobo eziminyene zokuguquguquka (16QAM, 64QAM, 256QAM, njll.), noma kubhendi yefrikhwensi ebanzi ngokusebenzisa i-low-density modulation (BPSK, QPSK ). Ukusetshenziswa kokuguquguquka kwe-low-density yemisebenzi enjalo kungcono ngenxa yokungavikeleki komsindo okuphezulu. Ngakho-ke, ukuzwela kowamukelayo kungcono, ngokufanele, isabelomali samandla semodemu siyanda futhi, ngenxa yalokho, ububanzi bokuxhumana.

Kwesinye isikhathi abakhiqizi be-UAV babeka isivinini solwazi sesixhumanisi somsakazo sibe phezulu kakhulu kunejubane lomthombo, ngokwezwi nezwi izikhathi ezi-2 noma ngaphezulu, bephikisana ngokuthi imithombo enjengamakhodekhi wevidiyo ine-bitrate eguquguqukayo futhi isivinini semodemu kufanele sikhethwe kucatshangelwa inani eliphakeme kakhulu. ukukhishwa kwe-bitrate. Kulokhu, ububanzi bokuxhumana buyancipha ngokwemvelo. Akufanele usebenzise le ndlela ngaphandle uma kunesidingo. Amamodemu amaningi esimanje ane-buffer enkulu kusidlulisi esingashelela ama-bitrate spikes ngaphandle kokulahlekelwa kwephakethe. Ngakho-ke, indawo yokugcina isivinini engaphezu kuka-25% ayidingeki. Uma kunesizathu sokukholelwa ukuthi umthamo webhafa wemodemu ethengwayo awanele futhi kudingeka ukwanda okukhulu kwesivinini, ngakho-ke kungcono ukwenqaba ukuthenga imodemu enjalo.

Ukubambezeleka kokudlulisa idatha

Lapho uhlola le pharamitha, kubalulekile ukwehlukanisa ukubambezeleka okuhlobene nokudluliswa kwedatha ngesixhumanisi somsakazo kusukela ekubambezelekeni okudalwe idivayisi yombhalo wekhodi/yokukhipha ikhodi yomthombo wolwazi, njengekhodekhi yevidiyo. Ukubambezeleka kwesixhumanisi somsakazo kuqukethe amanani angu-3.

1. Ukubambezeleka ngenxa yokucubungula isignali kumthumeli nomamukeli.
2. Ukubambezeleka ngenxa yokusatshalaliswa kwesignali ukusuka kumthumeli kuye kumamukeli.
3. Ukubambezeleka ngenxa yokubhafa kwedatha kusidlulisi kumamodemu we-time division duplex (TDD).

Ukubambezeleka kohlobo loku-1, kokuhlangenwe nakho kombhali, kusuka kumashumi amasekhondi amancane kuya ku-millisecond eyodwa. Ukulibaziseka kohlobo 2 kuncike ebangeni lokuxhumana, isibonelo, kusixhumanisi esingu-100 km singu-333 μs. Ukulibaziseka kohlobo 3 kuncike kubude bohlaka lwe-TDD kanye nesilinganiso sobude bomjikelezo wokudlulisela ukuya kubude besikhathi sozimele futhi kungahluka ukusuka ku-0 kuye kubude besikhathi bozimele, okungukuthi ukuhluka okungahleliwe. Uma iphakethe lemininingwane edlulisiwe likukokufaka kwe-transmitter ngenkathi imodemu ikumjikelezo wokudlulisela, khona-ke iphakethe lizodluliselwa emoyeni ngohlobo lwe-3 lokulibaziseka. Uma iphakethe seliphuzile kancane futhi umjikelezo wokwamukela usuqalile, khona-ke izobambezeleka kubhafa yesithumeli ngesikhathi somjikelezo wokwamukela . Ubude bozimele be-TDD obujwayelekile busuka ku-2 kuye ku-20 ms, ngakho-ke ukubambezeleka kohlobo 3 olubi kakhulu ngeke kudlule u-20 ms. Ngakho, ukubambezeleka okuphelele kusixhumanisi somsakazo kuzoba kububanzi obungu-3−21 ms.

Indlela engcono kakhulu yokuthola ukubambezeleka kwesixhumanisi somsakazo ukuhlola isikali esigcwele usebenzisa izinsiza ukuhlola izici zenethiwekhi. Ukulinganisa ukubambezeleka kusetshenziswa indlela yempendulo yesicelo akunconyiwe, njengoba ukubambezeleka kwezikhombisi-ndlela eziya phambili neziya emuva kungase kungafani kumamodemu e-TDD.

Isisindo nemingcele yobukhulu

Ukukhetha iyunithi yemodemu esebhodini ngokwalesi simiso akudingi ukuphawula okukhethekile: okuncane nokulula kuba ngcono. Ungakhohlwa futhi ngesidingo sokupholisa iyunithi ebhodini; ama-radiators engeziwe angadingeka, futhi ngokufanele, isisindo nobukhulu kungakhuphuka. Okuthandwayo lapha kufanele kunikezwe ukukhanya, amayunithi amancane asebenzisa amandla aphansi.

Kuyunithi esekelwe phansi, imingcele ye-mass-dimensional ayibucayi kangako. Ukusebenziseka kalula nokufaka kuya phambili. Iyunithi yaphansi kufanele ibe idivayisi evikelwe ngokuthembekile emithonyeni yangaphandle enesistimu yokukhweza elula ukuya ku-mast noma i-tripod. Inketho enhle yilapho iyunithi ephansi ihlanganiswa endlini efanayo ne-antenna. Ngokufanelekile, iyunithi yaphansi kufanele ixhunywe ohlelweni lokulawula ngesixhumi esisodwa esikahle. Lokhu kuzokusindisa emazwini aqinile lapho udinga ukwenza umsebenzi wokuthunyelwa endaweni emazingeni okushisa angama-−20 degrees.

Izidingo Zokudla

Amayunithi e-onboard, njengomthetho, akhiqizwa ngokusekelwa kwezinhlobo eziningi zama-voltage wokuhlinzeka, isibonelo 7-30 V, ehlanganisa iningi lezinketho zamandla kagesi kunethiwekhi yamandla ye-UAV. Uma unethuba lokukhetha kuma-voltage amaningana wokuhlinzeka, bese unikeza okuncamelayo kunani eliphansi kakhulu lokunikezwa kwamandla kagesi. Njengomthetho, amamodemu anikezwa amandla ngaphakathi kusuka ku-voltage engu-3.3 no-5.0 V ngokusebenzisa amandla esibili. Ukusebenza kahle kwalokhu kunikezwa kwamandla esibili kuphezulu, umehluko omncane phakathi kokufakwayo kanye ne-voltage yangaphakathi yemodemu. Ukwenyuka kokusebenza kahle kusho ukunciphisa ukusetshenziswa kwamandla nokukhiqiza ukushisa.

Amayunithi aphansi, ngakolunye uhlangothi, kufanele asekele amandla avela kumthombo wamandla kagesi aphezulu. Lokhu kuvumela ukusetshenziswa kwekhebula lamandla elinesiphambano esincane, esinciphisa isisindo futhi senze ukufakwa kube lula. Zonke ezinye izinto ziyalingana, nikeza okuncamelayo kumayunithi asekelwe phansi anokusekelwa kwe-PoE (Amandla phezu kwe-Ethernet). Kulokhu, ikhebula le-Ethernet elilodwa kuphela elidingekayo ukuze kuxhunywe iyunithi ephansi esiteshini sokulawula.

Isilawuli esihlukile/isiteshi se-telemetry

Isici esibalulekile ezimeni lapho singekho isikhala esisele ku-UAV sokufaka imodemu ehlukile yomyalo-telemetry. Uma kunesikhala, khona-ke isiteshi esihlukile sokulawula/i-telemetry semodemu ye-broadband singasetshenziswa njengesipele. Lapho ukhetha imodemu enale nketho, naka iqiniso lokuthi imodemu isekela umthetho olandelwayo ofisa ukuxhumana ne-UAV (i-MAVLink noma i-proprietary) kanye nekhono lokuphindaphinda idatha yesiteshi/ye-telemetry ibe isixhumi esibonakalayo esikahle esiteshini esiphansi (GS). ). Isibonelo, iyunithi esebhodini yemodemu ye-broadband ixhunywe ku-autopilot nge-interface efana ne-RS232, UART noma i-CAN, futhi iyunithi ephansi ixhunywe kukhompuyutha yokulawula ngesixhumi esibonakalayo se-Ethernet okudingeka ngayo ukushintshanisa umyalo. , i-telemetry nolwazi lwevidiyo. Kulesi simo, imodemu kufanele ikwazi ukuphindaphinda umyalo nokusakazwa kwe-telemetry phakathi kwe-RS232, UART noma i-CAN yokusebenzelana kweyunithi yebhodi kanye nesixhumi esibonakalayo se-Ethernet seyunithi yaphansi.

Amanye amapharamitha okufanele uwanake

Ukutholakala kwemodi ye-duplex. Amamodemu e-Broadband ama-UAV asekela izindlela zokusebenza ezilula noma eziyi-duplex. Kumodi elula, ukudluliswa kwedatha kuvunyelwe kuphela ohlangothini olusuka ku-UAV luye ku-NS, nakumodi ye-duplex - kuzo zombili izinkomba. Njengomthetho, amamodemu alula anekhodekhi yevidiyo eyakhelwe ngaphakathi futhi aklanyelwe ukusebenza namakhamera wevidiyo angenayo i-codec yevidiyo. Imodemu ye-simplex ayifanele ukuxhuma kukhamera ye-IP nanoma imaphi amanye amadivayisi adinga uxhumano lwe-IP. Ngokuphambene nalokho, imodemu eyi-duplex, njengomthetho, iklanyelwe ukuxhuma inethiwekhi ye-IP esebhodini ye-UAV nenethiwekhi ye-IP ye-NS, okungukuthi isekela amakhamera we-IP namanye amadivaysi e-IP, kodwa ingase ingabi nayo eyakhelwe- ku-codec yevidiyo, njengoba amakhamera wevidiyo we-IP ngokuvamile anekhodekhi yevidiyo yakho. Ukusekelwa kwesixhumi esibonakalayo se-Ethernet kungenzeka kuphela kumamodemu e-duplex egcwele.

Ukwamukela ukuhlukahluka (i-RX diversity). Ukuba khona kwaleli khono kuyisibopho ukuze kuqinisekiswe ukuxhumana okuqhubekayo kulo lonke ibanga lendiza. Lapho esakaza phezu kobuso boMhlaba, amaza omsakazo afika endaweni yokwamukela eyimishayo emibili: endleleni eqondile futhi ebonisa ukusuka phezulu. Uma ukwengezwa kwamagagasi emishayo emibili kwenzeka esigabeni, khona-ke insimu endaweni yokwamukela iyaqiniswa, futhi uma ku-antiphase, iyancipha. Ukuncipha kungase kube okuphawulekayo - kuze kufike ekulahlekelweni okuphelele kokuxhumana. Ukuba khona kwama-antenna amabili ku-NS, atholakala ezindaweni eziphakeme ezihlukene, kusiza ukuxazulula le nkinga, ngoba uma endaweni ye-antenna eyodwa imishayo yengezwa ku-antiphase, khona-ke endaweni yomunye awenzi. Ngenxa yalokho, ungakwazi ukufinyelela ukuxhumana okuzinzile kulo lonke ibanga.
Ama-topology enethiwekhi asekelwe. Kutuswa ukukhetha imodemu enikeza ukwesekwa hhayi kuphela kwe-point-to-point (PTP) topology, kodwa futhi ne-point-to-multipoint (PMP) kanye ne-relay (repeater) topology. Ukusetshenziswa kwe-relay ngokusebenzisa i-UAV eyengeziwe kukuvumela ukuthi unwebe kakhulu indawo yokumboza ye-UAV eyinhloko. Ukusekelwa kwe-PMP kuzokuvumela ukuthi uthole ulwazi ngesikhathi esisodwa kuma-UAV amaningana ku-NS eyodwa. Sicela futhi uqaphele ukuthi ukusekela i-PMP nokudluliselwa kuzodinga ukukhushulwa komkhawulokudonsa wemodemu uma kuqhathaniswa nendaba yokuxhumana ne-UAV eyodwa. Ngakho-ke, kulezi zindlela kunconywa ukuthi ukhethe imodemu esekela i-band frequency band (okungenani i-15-20 MHz).

Ukutholakala kwezindlela zokwandisa ukuvikeleka komsindo. Inketho ewusizo, uma kubhekwa indawo yokuphazamiseka okukhulu ezindaweni lapho kusetshenziswa khona ama-UAV. Ukungavikeleki komsindo kuqondwa njengekhono lesistimu yezokuxhumana ukwenza umsebenzi walo lapho kukhona ukuphazamiseka kwemvelaphi yokwenziwa noma yemvelo esiteshini sokuxhumana. Kunezindlela ezimbili zokulwa nokuphazamiseka. Indlela yoku-1: klama isamukeli semodemu ukuze ikwazi ukuthola ulwazi ngokuthembekile ngisho nalapho kukhona ukuphazamiseka kwebhendi yesiteshi sokuxhumana, ngezindleko zokwehliswa okuthile kwejubane lokudlulisa ulwazi. Indlela 2: Cindezela noma unciphise ukuphazamiseka kokokufaka komamukeli. Izibonelo zokusetshenziswa kwendlela yokuqala amasistimu wokusabalalisa ama-spectrum, okungukuthi: i-frequency hopping (FH), i-pseudo-random sequence spread spectrum (DSSS) noma inhlanganisela yakho kokubili. Ubuchwepheshe be-FH buye banda eziteshini zokulawula i-UAV ngenxa yezinga eliphansi elidingekayo lokudluliswa kwedatha kusiteshi esinjalo sokuxhumana. Isibonelo, ngesivinini esingu-16 kbit/s kubhendi engu-20 MHz, izikhundla ezingaba ngu-500 zemvamisa zingahlelwa, okuvumela ukuvikeleka okuthembekile ekuphazamisekeni kwebhande elincane. Ukusetshenziswa kwe-FH yesiteshi sokuxhumana se-broadband kuyinkinga ngoba ibhendi yefrikhwensi ewumphumela inkulu kakhulu. Isibonelo, ukuze uthole izikhundla zefrikhwensi engu-500 uma usebenza ngesiginali enomkhawulokudonsa ongu-4 MHz, uzodinga u-2 GHz womkhawulokudonsa wamahhala! Kuningi kakhulu ukuba ngokoqobo. Ukusetshenziswa kwe-DSSS yesiteshi sokuxhumana se-broadband nama-UAV kubaluleke kakhulu. Kulobu buchwepheshe, ibhithi yolwazi ngayinye iphindwa kanyekanye kumafrikhwensi ambalwa (noma kuwo wonke) kubhendi yesignali futhi, lapho kukhona ukuphazamiseka kwebhande elincane, ingahlukaniswa ezingxenyeni ze-spectrum ezingathintwa ukuphazamiseka. Ukusetshenziswa kwe-DSSS, kanye ne-FH, kusho ukuthi lapho kuvela ukuphazamiseka esiteshini, kuzodingeka kwehliswe izinga lokudluliswa kwedatha. Noma kunjalo, kusobala ukuthi kungcono ukuthola ividiyo evela ku-UAV ngesinqumo esiphansi kunalutho nhlobo. I-Approach 2 isebenzisa iqiniso lokuthi ukuphazamiseka, ngokungafani nomsindo wangaphakathi womamukeli, kungena isixhumanisi somsakazo kusuka ngaphandle futhi, uma izindlela ezithile zikhona kumodemu, zingacindezelwa. Ukucindezelwa kokugxambukela kungenzeka uma kutholakala ezindaweni ezibukwayo, zesikhashana noma zendawo. Isibonelo, ukuphazamiseka kwe-narrowband kwenziwa endaweni endaweni ye-spectral futhi "kunganqunywa" ku-spectrum usebenzisa isihlungi esikhethekile. Ngokufanayo, umsindo we-pulsed wenziwa endaweni esizindeni sesikhathi; ukuze ucindezelwe, indawo ethintekile iyasuswa kusignali yokufaka yomamukeli. Uma ukuphazanyiswa kungeyona ibhande elincane noma i-pulsed, khona-ke i-spatial suppressor ingasetshenziswa ukuyicindezela, ngoba ukuphazamiseka kungena othini olwamukelayo lusuka emthonjeni lusuka ohlangothini oluthile. Uma uziro wephethini yemisebe ye-antenna etholayo ibekwe endaweni yomthombo wokuphazamiseka, ukuphazamiseka kuzocindezelwa. Amasistimu anjalo abizwa nge-adaptive beamforming & beam nulling systems.

Kusetshenziswe iphrothokholi yomsakazo. Abakhiqizi bemodemu bangasebenzisa indinganiso (i-WiFi, i-DVB-T) noma iphrothokholi yomsakazo wobunikazi. Le parameter ayivamisile ukukhonjiswa emibhalweni. Ukusetshenziswa kwe-DVB-T kuboniswa ngokungaqondile amabhendi efrikhwensi asekelwayo 2/4/6/7/8, ngezinye izikhathi 10 MHz kanye nokushiwo embhalweni wokucaciswa kobuchwepheshe be-COFDM (coded OFDM) lapho i-OFDM isetshenziswa khona ngokuhlanganyela. enombhalo wekhodi ongazwani nomsindo. Ngokuhamba kwesikhathi, siyaqaphela ukuthi i-COFDM iyisiqubulo sokukhangisa futhi ayinazo izinzuzo kune-OFDM, njengoba i-OFDM engenakho ukubhala ngekhodi engazwani nomsindo ayilokothi isetshenziswe. Linganisa i-COFDM ne-OFDM uma ubona lezi zifinyezo ekucacisweni kwemodemu yomsakazo.

Amamodemu asebenzisa iphrothokholi ejwayelekile ngokuvamile akhiwa ngesisekelo se-chip ekhethekile (WiFi, DVB-T) esebenza ngokubambisana ne-microprocessor. Ukusebenzisa i-chip yangokwezifiso kukhulula umkhiqizi wemodemu ezinhlotsheni eziningi zekhanda ezihambisana nokuklama, ukumodela, ukusebenzisa, nokuhlola iphrothokholi yomsakazo wabo. I-microprocessor isetshenziselwa ukunikeza imodemu ukusebenza okudingekayo. Amamodemu anjalo anezinzuzo ezilandelayo.

1. Intengo ephansi.
2. Isisindo esihle nemingcele yesayizi.
3. Ukusetshenziswa kwamandla okuphansi.

Kukhona nokubi.

1. Ukungakwazi ukushintsha izici zesixhumi esibonakalayo somsakazo ngokushintsha i-firmware.
2. Ukuzinza okuphansi kwezimpahla esikhathini eside.
3. Amandla anomkhawulo ekunikezeni ukwesekwa kobuchwepheshe okufanelekile lapho kuxazululwa izinkinga ezingajwayelekile.

Ukuzinza okuphansi kwempahla kungenxa yokuthi abakhiqizi be-chip bagxila kakhulu ezimakethe ezinkulu (ama-TV, amakhompyutha, njll.). Abakhiqizi bamamodemu ama-UAV abayona into eza kuqala kubo futhi abakwazi nganoma iyiphi indlela ukuba nomthelela esinqumweni somkhiqizi we-chip sokuyeka ukukhiqiza ngaphandle kokushintshwa okwanele ngomunye umkhiqizo. Lesi sici siqiniswa umkhuba wokupakisha izixhumanisi zomsakazo zibe ama-microcircuits akhethekile njengokuthi “isistimu ku-chip” (Isistimu ku-Chip - SoC), ngakho-ke ama-chips okuxhumana omsakazo ngamunye ayagezwa kancane kancane emakethe ye-semiconductor.

Amakhono alinganiselwe ekunikezeni ukwesekwa kobuchwepheshe abangelwa ukuthi amaqembu okuthuthukisa amamodemu asekelwe esivumelwaneni somsakazo esijwayelekile agcwele ochwepheshe, ikakhulukazi kubuchwepheshe be-electronics kanye ne-microwave. Bangase bangabibikho nhlobo ochwepheshe bezokuxhumana lapho, ngoba azikho izinkinga okufanele bazixazulule. Ngakho-ke, abakhiqizi be-UAV abafuna izixazululo zezinkinga zokuxhumana ngomsakazo okungatheni bangase bazithole bephoxekile mayelana nokubonisana nosizo lobuchwepheshe.

Amamodemu asebenzisa iphrothokholi yerediyo yobunikazi akhiwe phezu kwesisekelo se-analog yendawo yonke kanye nama-chips okucubungula isignali yedijithali. Ukuzinza kokunikezwa kwama-chips anjalo kuphezulu kakhulu. Yiqiniso, intengo nayo iphezulu. Amamodemu anjalo anezinzuzo ezilandelayo.

1. Amathuba abanzi okwenza imodemu ihambisane nezidingo zekhasimende, okuhlanganisa ukulungisa isixhumi esibonakalayo somsakazo ngokushintsha i-firmware.
2. Amakhono engeziwe okuxhumana omsakazo athakasela ukusetshenziswa kuma-UAV futhi awekho kumamodemu akhelwe kusisekelo sezimiso ezijwayelekile zomsakazo.
3. Ukuzinza okuphezulu kwempahla, kuhlanganisa. esikhathini eside.
4. Izinga eliphezulu lokusekela lobuchwepheshe, okuhlanganisa nokuxazulula izinkinga ezingajwayelekile.

Amaphutha.

1. Intengo ephezulu.
2. Isisindo nosayizi amapharamitha angaba kubi kakhulu kunalawo amamodemu asebenzisa izimiso zomsakazo ezijwayelekile.
3. Ukwenyuka kokusetshenziswa kwamandla kweyunithi yokucubungula isignali yedijithali.

Idatha yobuchwepheshe yamanye amamodemu ama-UAV

Ithebula libonisa imingcele yobuchwepheshe yamanye amamodemu ama-UAV atholakala emakethe.

Qaphela ukuthi nakuba imodemu ye-3D Link inamandla okudlulisela aphansi kakhulu uma iqhathaniswa ne-Picoradio OEM kanye nemodemu ye-J11 (25 dBm vs. 27−30 dBm), isabelomali samandla se-3D Link singaphezu kwalawo mamodemu ngenxa yokuzwela kwesamukeli esiphezulu (nge- isivinini sokudlulisa idatha esifanayo samamodemu aqhathaniswayo). Ngakho, ibanga lokuxhumana uma usebenzisa i-3D Link lizoba likhulu ngokuba namandla okuntshontsha kangcono.

Ithebula. Idatha yobuchwepheshe yamanye amamodemu e-broadband yama-UAV namarobhothi

Ipharamitha
Isixhumanisi se-3D
I-Skyhopper PRO
I-Picoradio OEM (yenziwe kumojula Idatha ye-PDL2450 kusuka ku-Microhard)
I-SOLO7
(bhekafuthi Isamukeli se-SOLO7)
J11

Umkhiqizi, izwe
Geoscan, RF
Mobilicom, Israel
I-Airborne Innovations, eCanada
I-DTC, UK
Redess, China

Ibanga lokuxhumana [km] 20−60
5
n/a*
n/a*
I-10 − 20

Isivinini [Mbit/s] 0.023−64.9
I-1.6 − 6
I-0.78 − 28
I-0.144 − 31.668
I-1.5 − 6

Ukubambezeleka kokudluliswa kwedatha [ms] 1−20
25
n/a*
I-15 − 100
I-15 − 30

Ubukhulu beyunithi esebhodini LxWxH [mm] 77x45x25
74h54h26
40x40x10 (ngaphandle kwezindlu)
67h68h22
76h48h20

Isisindo seyunithi ebhodini [igremu] 89
105
17.6 (ngaphandle kwezindlu)
135
88

Ulwazi interface
I-Ethernet, RS232, CAN, USB
I-Ethernet, RS232, USB (uma uthanda)
I-Ethernet, RS232/UART
I-HDMI, i-AV, i-RS232, i-USB
I-HDMI, i-Ethernet, i-UART

Ukunikezwa kwamandla kweyunithi esebhodini [I-Volt/Watt] 7−30/6.7
7−26/n/a*
5−58/4.8
5.9−17.8/4.5−7
7−18/8

Iyunithi yamandla aphansi [Volt/Watt] 18−75 noma i-PoE/7
7−26/n/a*
5−58/4.8
6−16/8
7−18/5

Amandla okudlulisa [dBm] 25
n/a*
I-27 − 30
20
30

Ukuzwela umamukeli [dBm] (ngesivinini [Mbit/s])
−122(0.023) −101(4.06) −95.1(12.18) −78.6(64.96)
−101(n/a*)
−101(0.78) −96(3.00) −76(28.0)
−95(n/a*) −104(n/a*)
−97(1.5) −94(3.0) −90(6.0)

Ibhajethi yamandla emodemu [dB] (yesivinini [Mbit/sec])
147(0.023) 126(4.06) 120.1(12.18) 103.6(64.96)
n/a*
131(0.78) 126(3.00) 103(28.0)
n/a*
127 (1.5) 124 (3.0) 120 (6.0)

Amabhendi efrikhwensi asekelwe [MHz] 4−20
I-4.5; I-8.5
I-2; I-4; I-8
0.625; 1.25; 2.5; 6; 7; 8
I-2; I-4; I-8

I-Simplex/duplex
I-Duplex
I-Duplex
I-Duplex
I-Simplex
I-Duplex

Ukwesekwa kwezinhlobonhlobo
yebo
yebo
yebo
yebo
yebo

Isiteshi esihlukene sokulawula/i-telemetry
yebo
yebo
yebo
akukho
yebo

Izivumelwano zokulawula i-UAV ezisekelwe esiteshini sokulawula/i-telemetry
I-MAVLink, i-proprietary
I-MAVLink, i-proprietary
akukho
akukho
I-MAVLink

Ukwesekwa okuningiliziwe ekulawuleni/kusiteshi se-telemetry
yebo
yebo
akukho
akukho
n/a*

Ama-topology enethiwekhi
I-PTP, i-PMP, i-relay
I-PTP, i-PMP, i-relay
I-PTP, i-PMP, i-relay
I-PTP
I-PTP, i-PMP, i-relay

Izindlela zokwandisa ukungavikeleki komsindo
I-DSSS, i-narrowband kanye ne-pulse suppressors
n/a*
n/a*
n/a*
n/a*

Iphrothokholi yomsakazo
okuphathelene
n/a*
n/a*
I-DVB-T
n/a*

* n/a - ayikho idatha.

Mayelana nomlobi

Alexander Smorodinov [[i-imeyili ivikelwe]] uchwepheshe oholayo kwa-Geoscan LLC emkhakheni wezokuxhumana okungenantambo. Kusukela ngo-2011 kuze kube manje, ubelokhu enza izimiso zomsakazo kanye nama-algorithms okucubungula amasignali amamodemu omsakazo we-broadband ngezinjongo ezihlukahlukene, kanye nokusebenzisa ama-algorithms athuthukisiwe asekelwe kuma-logic chips ahlelekayo. Izindawo ezithakaselwayo zombhali zifaka phakathi ukuthuthukiswa kwama-algorithms okuvumelanisa, isilinganiso sendawo yesiteshi, ukushintshashintsha/ukwehliswa kwenani, ukubhala ngekhodi okungazwani nomsindo, kanye nama-algorithms athile wokufinyelela kwemidiya (i-MAC). Ngaphambi kokujoyina i-Geoscan, umbhali usebenze ezinhlanganweni ezahlukahlukene, ethuthukisa amadivaysi okuxhumana angenantambo angokwezifiso. Kusukela ngo-2002 kuya ku-2007, usebenze e-Proteus LLC njengochwepheshe ohamba phambili ekuthuthukisweni kwezinhlelo zokuxhumana ezisekelwe kuzinga le-IEEE802.16 (WiMAX). Kusukela ngo-1999 kuya ku-2002, umbhali ubambe iqhaza ekuthuthukisweni kwama-algorithms okuvimbela umsindo kanye nokumodela imizila yezixhumanisi zomsakazo e-Federal State Unitary Enterprise Central Research Institute "Granit". Umbhali uthole iziqu ze-Candidate of Technical Sciences e-St. Petersburg University of Aerospace Instrumentation ngo-1998 kanye neziqu zeRadio Engineering azithola kuyona le nyuvesi ngo-1995. U-Alexander uyilungu lamanje le-IEEE kanye ne-IEEE Communications Society.

Source: www.habr.com