Umceli mngeni wokuhambisa inani elikhulu ledatha ukusuka kwinqwelo-moya engabonakaliyo (UAV) okanye i-robotics yomhlaba ayiqhelekanga kwizicelo zanamhlanje. Eli nqaku lixoxa ngeendlela zokukhetha iimodem zebroadband kunye neengxaki ezinxulumene nazo. Eli nqaku libhalelwe i-UAV kunye nabaphuhlisi berobhothi.
Criteria Criteria
Iikhrayitheriya eziphambili zokukhetha imodem yebroadband yee-UAVs okanye iirobhothi zezi:
- Uluhlu lonxibelelwano.
- Ubungakanani bogqithiselo lwedatha.
- Ukulibaziseka ekugqithiseni idatha.
- Ubunzima kunye nemilinganiselo yeeparamitha.
- Ujongano lolwazi oluxhaswayo.
- Iimfuno zesondlo.
- Ulawulo olwahlukileyo / umjelo wetelemetry.
Uluhlu lonxibelelwano
Uluhlu lonxibelelwano aluxhomekanga kuphela kwimodem, kodwa nakwii-eriyali, iintambo ze-eriyali, iimeko zokusasaza amaza erediyo, ukuphazamiseka kwangaphandle kunye nezinye izizathu. Ukuze uhlukanise iiparamitha zemodem ngokwayo kwezinye iiparameters ezichaphazela uluhlu lonxibelelwano, qwalasela uluhlu lwe-equation [Kalinin A.I., Cherenkova E.L. Ukusasazwa kwamaza erediyo kunye nokusebenza kweekhonkco zerediyo. Uqhagamshelwano. 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}},$$display$$
apho
$ inline $ R $ inline $ - olufunekayo uluhlu lonxibelelwano kwiimitha;
$ inline $ F $ inline $ - frequency in Hz;
$ inline $ P_{TXdBm} $ inline $ - modem transmitter amandla kwi dBm;
$ inline $ G_{TXdB} $ inline $ - transmitter antenna inzuzo kwi dB;
$ inline $ L_{TXdB} $ inline $ - ilahleko kwikhebula ukusuka kwimodem ukuya kwi-antenna yokuhambisa kwi-dB;
I-$ inline $ G_{RXdB}$inline$ - inzuzo ye-antenna yomamkeli kwi-dB;
I-$ inline $ L_{RXdB} $ inline $ - ilahleko kwikhebula ukusuka kwimodem ukuya kwi-antenna yomamkeli kwi-dB;
$inline$P_{RXdBm}$inline$ - uvakalelo lomamkeli wemodem kwidBm;
I-$inline$|V|_{dB}$inline$ yimeko yokuthomalalisa eqwalasela ilahleko eyongezelelweyo ngenxa yempembelelo yomhlaba, izityalo, umoya kunye nezinye izinto kwi-dB.
Ukusuka kuluhlu lwe-equation kucacile ukuba uluhlu luxhomekeke kuphela kwiiparameters ezimbini zemodem: amandla okuhambisa i-$inline$P_{TXdBm}$inline$ kunye novakalelo lwamamkeli $inline$P_{RXdBm}$inline$, okanye kunoko kumahluko wabo. - uhlahlo lwabiwo-mali lwamandla emodem
$$display$$B_m=P_{TXdBm}-P_{RXdBm}.$$display$$
Iiparamitha eziseleyo kwi-equation yoluhlu zichaza iimeko zokusabalalisa umqondiso kunye neeparitha zezixhobo ze-antenna-feeder, okt. ayinanto yakwenza nemodem.
Ngoko ke, ukuze ukwandise uluhlu lonxibelelwano, kufuneka ukhethe imodem enexabiso elikhulu le-$inline$B_m$inline$. Ngokulandelayo, i-$inline$B_m$inline$ inokunyuswa ngokunyusa i-$inline$P_{TXdBm}$inline$ okanye ngokunciphisa i$inline$P_{RXdBm}$inline$. Kwiimeko ezininzi, abaphuhlisi be-UAV bafuna imodem enegunya eliphezulu lokudlulisa kwaye banike ingqwalasela encinci kubuntununtunu bomamkeli, nangona kufuneka benze ngokuchaseneyo. Isidlulisi esinamandla esisebhodini semodem yebroadband siquka ezi ngxaki zilandelayo:
- ukusetyenziswa kwamandla aphezulu;
- imfuneko yokupholisa;
- ukuwohloka kokuhambelana kwe-electromagnetic (EMC) kunye nezinye izixhobo ezisebhodini ze-UAV;
- imfihlo yamandla aphantsi.
Iingxaki ezimbini zokuqala zinxulumene nento yokuba iindlela zale mihla zokusasaza isixa esikhulu solwazi kwijelo likanomathotholo, umzekelo iOFDM, zifuna. umgca umthumeli. Ukusebenza kakuhle kosasazo lwerediyo yanamhlanje kuphantsi: 10–30%. Ngaloo ndlela, i-70-90% yamandla axabisekileyo ombane we-UAV aguqulwa abe ngubushushu, okufuneka asuswe ngokufanelekileyo kwimodem, ngaphandle koko iya kusilela okanye amandla ayo aphumayo aya kuhla ngenxa yokushisa kakhulu ngexesha elingafanelekanga. Ngokomzekelo, i-2 W i-transmitter iya kutsala i-6-20 W ukusuka kumandla ombane, apho i-4-18 W iya kuguqulwa ibe shushu.
I-energy stealth yekhonkco yerediyo ibalulekile kwizicelo ezikhethekileyo kunye nezomkhosi. Ubuchwephesha obuphantsi buthetha ukuba isignali yemodem ichongiwe ngokunokwenzeka okuphezulu ngumamkeli wolwazi wesikhululo se-jamming. Ngokufanelekileyo, amathuba okucinezela ikhonkco likanomathotholo nge-stealth yamandla aphantsi nawo aphezulu.
Uvakalelo lomamkeli wemodem lubonakalisa ukukwazi ukukhupha ulwazi kwiimpawu ezifunyenweyo kunye nenqanaba elinikiweyo lomgangatho. Iikhrayitheriya zomgangatho zinokwahluka. Kwiinkqubo zonxibelelwano lwedijithali, ukuba nokwenzeka kwempazamo encinci (isantya sempazamo encinci - i-BER) okanye ukubakho kwempazamo kwipakethi yolwazi (isantya sempazamo yesakhelo - FER) sisetyenziswa rhoqo. Ngokwenyani, ubuntununtunu linqanaba lomqondiso kanye apho ulwazi kufuneka lukhutshwe khona. Umzekelo, ubuntununtunu be-−98 dBm nge-BER = 10−6 bubonisa ukuba ulwazi olune-BER olunjalo lunokutsalwa kumqondiso onenqanaba -98 dBm okanye ngaphezulu, kodwa ulwazi olunenqanaba, yithi, −99 dBm ayisayi kukhutshwa kumqondiso onenqanaba, yithi, −1 dBm. Ewe kunjalo, ukuhla komgangatho njengoko inqanaba lomqondiso liyancipha kwenzeka ngokuthe ngcembe, kodwa kufanelekile ukukhumbula ukuba uninzi lweemodem zanamhlanje zinento ebizwa ngokuba yi. isiphumo se-threshold apho ukuhla komgangatho xa inqanaba lomqondiso liyancipha ngaphantsi kobuthathaka kwenzeka ngokukhawuleza okukhulu. Kwanele ukunciphisa isignali nge-2-10 dB ngaphantsi kovakalelo lwe-BER ukwandisa ukuya kwi-1-XNUMX, oku kuthetha ukuba awuyi kuphinda ubone ividiyo kwi-UAV. Isiphumo somda sisiphumo esithe ngqo sethiyori kaShannon yetshaneli enengxolo; ayinakususwa. Ukutshatyalaliswa kolwazi xa inqanaba lomqondiso liyancipha ngaphantsi kovakalelo lwenzeka ngenxa yempembelelo yengxolo eyenziwa ngaphakathi kommkeli ngokwawo. Ingxolo yangaphakathi yomamkeli ayikwazi ukupheliswa ngokupheleleyo, kodwa kunokwenzeka ukunciphisa inqanaba layo okanye ukufunda ukukhupha ngokufanelekileyo ulwazi oluvela kwisignali enomsindo. Abavelisi bemodem basebenzisa zombini ezi ndlela, besenza uphuculo kwiibhloko zeRF zomamkeli kunye nokuphucula iindlela zokusetyenzwa komqondiso wedijithali. Ukuphucula uvakalelo lomamkeli wemodem akukhokeleli ekunyukeni okumangalisayo kokusetyenziswa kwamandla kunye nokutshatyalaliswa kobushushu njengokwandisa amandla okuhambisa. Kukho, ewe, ukonyuka kokusetyenziswa kwamandla kunye nokuveliswa kobushushu, kodwa kuthobeke kakhulu.
I-algorithm elandelayo yokukhetha imodem iyanconywa ukusuka kwindawo yokujonga ukufezekisa uluhlu olufunekayo lonxibelelwano.
- Gqiba ngereyithi yokudluliselwa kwedatha.
- Khetha imodem enovakalelo olungcono lwesantya esifunekayo.
- Qinisekisa uluhlu lonxibelelwano ngokubala okanye umfuniselo.
- Ukuba uluhlu lonxibelelwano lubonakala lungaphantsi kunemfuneko, zama ukusebenzisa la manyathelo alandelayo (acwangciswe ngolandelelwano lokunciphisa okuphambili):
- ukunciphisa ilahleko kwiintambo ze-antenna $ inline $ L_{TXdB} $ inline $, $ inline $ L_{RXdB} $ inline $ ngokusebenzisa intambo kunye nokunciphisa umgca ophantsi kwi-frequency yokusebenza kunye / okanye ukunciphisa ubude beentambo;
- ukwandisa inzuzo ye-eriyali $ inline $ G_{TXdB} $ inline $, $ inline $ G_{RXdB} $ inline $;
- ukwandisa amandla okuhambisa imodem.
Amaxabiso obuthathaka axhomekeke kwireyithi yokudluliselwa kwedatha ngokomgaqo: isantya esiphezulu - ngakumbi uvakalelo. Umzekelo, uvakalelo lwe-−98 dBm lwe-8 Mbps lungcono kuno--95 dBm ubuntununtunu be-12 Mbps. Unokuthelekisa iimodem ngokwemiqathango yovakalelo kuphela kwisantya esifanayo sokudlulisa idatha.
Idata kumandla othumelo lothumelo phantse isoloko ifumaneka kwiinkcukacha zemodem, kodwa idatha kumamkeli wobuntununtunu ayisoloko ikhona okanye ayanelanga. Ubuncinci, esi sisizathu sokuba silumke, kuba amanani amahle kunzima ukufihla. Ukongezelela, ngokungashicileli idatha yobuntununtunu, umenzi unqanda umthengi ithuba lokuqikelela uluhlu lonxibelelwano ngokubala. до ukuthengwa kwemodem.
Ubungakanani bogqithiselo lwedatha
Ukukhetha imodem esekelwe kule parameter kulula ukuba iimfuno zesantya zichazwe ngokucacileyo. Kodwa kukho ama-nuances athile.
Ukuba ingxaki isonjululwe ifuna ukuba kuqinisekiswe ubuninzi bonxibelelwano olunokwenzeka kwaye kwangaxeshanye kunokwenzeka ukwabela ibhendi yefrikhwensi eyaneleyo kwikhonkco lonomathotholo, ke kungcono ukhethe imodem exhasa ibhendi ebanzi (bandwidth). Inyani kukuba isantya solwazi esifunekayo sinokufezekiswa kwibhendi yefrikhwensi encinci ngokusebenzisa iintlobo ezixineneyo zokumodareyitha (16QAM, 64QAM, 256QAM, njl.), okanye kwibhendi ebanzi yamaza ngokusebenzisa ukumodareyitha koxinzelelo oluphantsi (BPSK, QPSK). ). Ukusetyenziswa kwemodyuli yoxinaniso oluphantsi kwimisebenzi enjalo ikhethwayo ngenxa yokungakhuseleki kwayo kwingxolo ephezulu. Ngoko ke, uvakalelo lomamkeli lungcono; ngokufanelekileyo, uhlahlo lwabiwo-mali lwemodem luyanda kwaye, ngenxa yoko, uluhlu lonxibelelwano.
Ngamanye amaxesha abavelisi be-UAV babeka isantya solwazi lwekhonkco yerediyo ephezulu kakhulu kunesantya somthombo, ngokoqobo i-2 okanye amaxesha amaninzi, bephikisana ukuba imithombo efana ne-codecs yevidiyo ine-bitrate eguquguqukayo kwaye isantya semodem kufuneka sikhethwe ngokuqwalasela ixabiso eliphezulu. ukukhutshwa kwebitrate. Kule meko, uluhlu lonxibelelwano luyancipha ngokwendalo. Akufanele usebenzise le ndlela ngaphandle kokuba kuyimfuneko. Uninzi lweemodem zangoku zine-buffer enkulu kwi-transmitter enokuthi igudise i-bitrate spikes ngaphandle kokulahleka kwepakethi. Ngoko ke, ukugcinwa kwesantya esingaphezu kwe-25% akufuneki. Ukuba kukho isizathu sokukholelwa ukuba umthamo we-buffer yemodem ethengwayo ayanelanga kwaye ukunyuka okukhulu kwesantya kuyafuneka, ngoko kungcono ukwala ukuthenga imodem enjalo.
Ukulibaziseka kokudluliselwa kwedatha
Xa uvavanya le parameter, kubalulekile ukwahlula ukulibaziseka okuhambelana nokuhanjiswa kwedatha kwikhonkco lerediyo ukusuka kulibaziseko olwenziwa yi-encoding/decoding device yomthombo wolwazi, njengekhodekhi yevidiyo. Ukulibaziseka kwikhonkco lerediyo liquka amaxabiso ama-3.
- Ukulibaziseka ngenxa yokusetyenzwa komqondiso kwi-transmitter kunye nomamkeli.
- Ukulibaziseka ngenxa yosasazo lomqondiso ukusuka kumthumeli ukuya kumamkeli.
- Ulibaziseko ngenxa yedata buffering kwi transmitter in time division duplex (TDD) modem.
Uhlobo lwe-1 latency, kumava ombhali, lusuka kwishumi le-microseconds ukuya kwi-millisecond enye. Ukulibaziseka kodidi lwe-2 kuxhomekeke kuluhlu lonxibelelwano, umzekelo, kwikhonkco le-100 km yi-333 μs. Ukulibaziseka kohlobo lwe-3 kuxhomekeke kubude besakhelo se-TDD kunye nomlinganiselo womjikelezo wothutho ukuya kwixesha elipheleleyo lesakhelo kwaye unokuhluka ukusuka kwi-0 ukuya kwixesha lesakhelo, oko kukuthi i-random variable. Ukuba ipakethe yolwazi oludlulisiweyo ikwigalelo lothumelo ngelixa imodem ikwindlela yokuhambisa, ke ipakethi iya kuhanjiswa emoyeni nge-zero yokulibaziseka uhlobo 3. Ukuba ipakethi isemva kancinci kwaye umjikelo wokwamkela sele uqalile, ngoko ke iya kulibaziseka kwi-transmitter buffer ngalo lonke ixesha lomjikelo wolwamkelo . Ubude obuqhelekileyo besakhelo se-TDD busuka kwi-2 ukuya kwi-20 ms, ngoko ke imeko embi kakhulu Uhlobo lwe-3 ukulibaziseka aluyi kudlula i-20 ms. Ngoko ke, ukulibaziseka kukonke kwikhonkco lerediyo kuya kuba kuluhlu lwe-3−21 ms.
Eyona ndlela ingcono yokufumanisa ukulibaziseka kwikhonkco likanomathotholo luvavanyo olupheleleyo olusebenzisa izinto eziluncedo ukuvavanya iimpawu zenethiwekhi. Akukhuthazwa ukulinganisa ukulibaziseka usebenzisa indlela yokuphendula isicelo, kuba ukulibaziseka kwindlela eya phambili kunye neyomva isenokungafani kwiimodem ze-TDD.
Ubunzima kunye nemilinganiselo yeeparamitha
Ukukhetha iyunithi yemodem ekwibhodi ngokwalo mgaqo ayifuni naziphi na izimvo ezikhethekileyo: ezincinci kunye nekhaphukhaphu zingcono. Ungalibali kwakhona malunga nesidingo sokupholisa iyunithi ekwibhodi, iiradiyetha ezongezelelweyo zinokufuneka, kwaye ngokufanelekileyo, ubunzima kunye nemilinganiselo inokunyuka. Ukukhethwa apha kufuneka kunikwe ukukhanya, iiyunithi ezincinci ezinobungakanani obuncinci bokusetyenziswa kwamandla.
Kwiyunithi esekwe emhlabeni, iiparamitha ezinobukhulu obukhulu azibalulekanga kangako. Ukusebenziseka ngokulula kunye nokufakwa kuza phambili. Iyunithi ephantsi kufuneka ibe sisixhobo esikhuseleke ngokuthembekileyo kwiimpembelelo zangaphandle kunye nenkqubo efanelekileyo yokuxhoma kwimasti okanye i-tripod. Inketho efanelekileyo xa iyunithi yomhlaba idibaniswa kwizindlu ezifanayo kunye ne-antenna. Ngokufanelekileyo, iyunithi yomhlaba kufuneka idibaniswe kwinkqubo yokulawula ngokusebenzisa enye ikhonkco efanelekileyo. Oku kuya kukusindisa kumagama anamandla xa ufuna ukwenza umsebenzi wokusasaza kwiqondo lobushushu le-−20 degrees.
Iimfuno zokutya
Iiyunithi ze-onboard, njengomthetho, ziveliswa ngenkxaso yoluhlu olubanzi lwee-voltages zokubonelela, umzekelo i-7-30 V, ehlanganisa ezininzi iinketho zombane kwi-UAV network network. Ukuba unethuba lokukhetha kwii-voltages ezininzi zokubonelela, ke unike ukhetho kwixabiso lombane lobonelelo oluphantsi. Njengomthetho, iimodem zinikwe amandla angaphakathi kwi-voltages ye-3.3 kunye ne-5.0 V ngokusebenzisa umbane wesibini. Ukusebenza kwezi zibonelelo zamandla esibini kuphezulu, umncinci umehluko phakathi kwegalelo kunye nombane wangaphakathi wemodem. Ukonyuka kokusebenza kakuhle kuthetha ukunciphisa ukusetyenziswa kwamandla kunye nokuveliswa kobushushu.
Iiyunithi ezisezantsi, kwelinye icala, kufuneka zixhase amandla avela kumthombo wamandla ombane aphezulu. Oku kuvumela ukusetyenziswa kwentambo yamandla kunye necandelo elincinci le-cross-section, elinciphisa ubunzima kunye nokwenza lula ukufakela. Zonke ezinye izinto zilingana, zinike ukhetho kwiiyunithi ezisekelwe emhlabeni kunye nenkxaso ye-PoE (Amandla phezu kwe-Ethernet). Kule meko, ikhebula elilodwa kuphela le-Ethernet lifunekayo ukudibanisa iyunithi yomhlaba kwisikhululo sokulawula.
Ulawulo olwahlukileyo / umjelo wetelemetry
Isici esibalulekileyo kwiimeko apho kungekho ndawo ishiywe kwi-UAV yokufaka imodem yomyalelo we-telemetry eyahlukileyo. Ukuba kukho indawo, ke ulawulo oluhlukeneyo/umzila wetelemetry wemodem yebroadband ingasetyenziswa njenge-backup. Xa ukhetha imodem ngolu khetho, nikela ingqalelo kwinto yokuba imodem ixhasa iprotocol efunwayo yonxibelelwano kunye ne-UAV (MAVLink okanye i-proprietary) kunye nokukwazi ukuphindaphinda i-multiplex yokulawula ishaneli / idatha ye-telemetry kwi-interface efanelekileyo kwisikhululo esisezantsi (GS). ). Ngokomzekelo, iyunithi yebhodi ye-modem ye-broadband ixhunyiwe kwi-autopilot nge-interface efana ne-RS232, i-UART okanye i-CAN, kwaye iyunithi yomhlaba idibaniswe kwikhompyutheni yokulawula nge-interface ye-Ethernet apho kuyimfuneko ukutshintshiselana ngomyalelo. , i-telemetry kunye nolwazi lwevidiyo. Kule meko, imodem kufuneka ikwazi ukuphindaphinda umyalelo kunye ne-telemetry stream phakathi kwe-RS232, i-UART okanye i-CAN i-interfaces yeyunithi yebhodi kunye ne-Ethernet interface yeyunithi yomhlaba.
Ezinye iiparameters zokunika ingqalelo
Ubukho bemowudi ye-duplex. Iimodem zebroadband ze-UAVs zixhasa iimowudi ezilula okanye eziphindwe kabini. Kwimo ye-simplex, ukuhanjiswa kwedatha kuvunyelwe kuphela kwicala elivela kwi-UAV ukuya kwi-NS, nakwimodi ye-duplex - kumacala omabini. Njengomthetho, iimodem ezilula zinekhowudi yevidiyo eyakhelweyo kwaye yenzelwe ukusebenza kunye neekhamera zevidiyo ezingenayo i-codec yevidiyo. Imodem elula ayifanelekanga ukudibanisa kwikhamera ye-IP okanye naziphi na ezinye izixhobo ezifuna uxhumano lwe-IP. Ngokuchasene noko, imodem eyi-duplex, njengomthetho, yenzelwe ukudibanisa inethiwekhi ye-IP ekwibhodi ye-UAV kunye nenethiwekhi ye-IP ye-NS, oko kukuthi ixhasa iikhamera ze-IP kunye nezinye izixhobo ze-IP, kodwa ayinakho i-built- kwikhodekhi yevidiyo, kuba iikhamera zevidiyo ze-IP zihlala zinekhowudi yakho yevidiyo. Inkxaso yojongano lwe-Ethernet inokwenzeka kuphela kwiimodem eziphindwe kabini.
Ulwamkelo lokwahlukahlukana (ukwahluka kwe-RX). Ubukho bobu buchule bunyanzelekile ukuqinisekisa unxibelelwano oluqhubekayo kuwo wonke umgama wokubhabha. Xa usasaza phezu komhlaba, amaza onomathotholo afika kwindawo yokufumana imiqadi emibini: ecaleni kwendlela ethe ngqo kunye nokubonakaliswa komphezulu. Ukuba ukongezwa kwamaza eentsimbi ezimbini kwenzeka kwisigaba, ngoko intsimi kwindawo yokufumana iqiniswa, kwaye ukuba kwi-antiphase, iyancipha. Ubuthathaka bunokubaluleka kakhulu-ukuya kuthi ga ekulahlekeni konxibelelwano. Ubukho bee-antenna ezimbini kwi-NS, ebekwe kwiindawo eziphakamileyo ezahlukeneyo, kunceda ukuxazulula le ngxaki, kuba ukuba kwindawo ye-antenna enye imiqadi yongezwa kwi-antiphase, ngoko kwindawo yomnye ayenzi. Ngenxa yoko, unokufezekisa uqhagamshelo oluzinzileyo kuwo wonke umgama.
Ii-topology zenethiwekhi ezixhaswayo. Kucetyiswa ukuba ukhethe imodem enika inkxaso kungekuphela nje kwi-point-to-point (PTP) topology, kodwa kunye ne-point-to-multipoint (PMP) kunye ne-relay (repeater) topology. Ukusetyenziswa kwe-relay ngokusebenzisa i-UAV eyongezelelweyo ikuvumela ukuba wandise kakhulu indawo yokugubungela i-UAV ephambili. Inkxaso ye-PMP iya kukuvumela ukuba ufumane ulwazi ngaxeshanye kwii-UAV ezininzi kwi-NS enye. Nceda uqaphele kwakhona ukuba ukuxhasa i-PMP kunye ne-relay kuya kufuna ukwanda kwe-modem bandwidth xa kuthelekiswa nemeko yonxibelelwano kunye ne-UAV enye. Ngoko ke, kwezi ndlela kucetyiswa ukuba ukhethe imodem exhasa band frequency ebanzi (ubuncinane 15-20 MHz).
Ubukho beendlela zokwandisa ukhuseleko lwengxolo. Inketho eluncedo, enikwe imeko yokuphazamiseka okukhulu kwiindawo apho kusetyenziswa ii-UAVs. Ukungazinzi kwengxolo kuqondwa njengamandla enkqubo yonxibelelwano ukwenza umsebenzi wayo phambi kokuphazamiseka kwemvelaphi eyenziweyo okanye yendalo kumjelo wonxibelelwano. Kukho iindlela ezimbini zokulwa nokuphazamiseka. Indlela yoku-1: yila ummkeli wemodem ukwenzela ukuba ikwazi ukufumana ulwazi ngokuthembekileyo nangona kukho ukuphazamiseka kwibhendi yejelo lonxibelelwano, ngeendleko zokunciphisa isantya sokudlulisa ulwazi. Indlela yesi-2: Cindezela okanye unciphise uphazamiseko kwigalelo lomamkeli. Imizekelo yokuphunyezwa kwendlela yokuqala ziinkqubo zokusasazwa kwe-spectrum, ezizezi: i-frequency hopping (FH), i-pseudo-random sequence spread spectrum (DSSS) okanye i-hybrid yazo zombini. I-teknoloji ye-FH iye yasasazeka kwiindlela zokulawula i-UAV ngenxa yezinga eliphantsi elifunekayo lokudlulisa idatha kwijelo lonxibelelwano olunjalo. Ngokomzekelo, kwisantya se-16 kbit / s kwibhendi ye-20 MHz, malunga nezikhundla ze-frequency ezingama-500 zinokucwangciswa, ezivumela ukukhuselwa okuthembekileyo ngokuchasene nokuphazamiseka kwebhendi encinci. Ukusetyenziswa kwe-FH kwitshaneli yonxibelelwano olubanzi kuyingxaki kuba ibhendi yefrikhwensi ephumayo inkulu kakhulu. Ngokomzekelo, ukufumana izikhundla ze-500 ze-frequency xa usebenza kunye nomqondiso kunye ne-4 MHz bandwidth, uya kufuna i-2 GHz ye-bandwidth yamahhala! Kakhulu ukuba yinyani. Ukusetyenziswa kwe-DSSS kumjelo wonxibelelwano olubanzi kunye nee-UAV kubaluleke kakhulu. Kobu buchwephesha, intwana yolwazi nganye iphindwa ngaxeshanye kwiifrikhwensi ezininzi (okanye kuzo zonke) kwibhendi yomqondiso kwaye, phambi kokuphazamiseka kwebhendi emxinwa, inokwahlulwa kumacandelo espectrum angachatshazelwa luphazamiseko. Ukusetyenziswa kwe-DSSS, kunye ne-FH, kuthetha ukuba xa ukuphazamiseka kubonakala kwitshaneli, ukunciphisa izinga lokuhanjiswa kwedatha kuya kufuneka. Nangona kunjalo, kuyacaca ukuba kungcono ukufumana ividiyo kwi-UAV ngesisombululo esisezantsi kunanto kwaphela. Indlela ye-2 isebenzisa into yokuba ukuphazamiseka, ngokungafani nesandi sangaphakathi sommkeli, ingena kwikhonkco yerediyo evela ngaphandle kwaye, ukuba kukho iindlela ezithile kwimodem, inokucinezelwa. Ukunyanzeliswa kokuphazamiseka kunokwenzeka ukuba kufakwe kwi-spectral, temporal okanye i-spatial domains. Ngokomzekelo, ukuphazamiseka kwe-narrowband kufakwe kwingingqi ye-spectral kwaye "inokunqunyulwa" kwi-spectrum usebenzisa i-filter ekhethekileyo. Ngokufanayo, ingxolo ye-pulsed ifakwe kwi-domain yexesha; ukuyicinezela, indawo echaphazelekayo iyasuswa kwisignali yegalelo lomamkeli. Ukuba uphazamiseko alukho ibhande elimxinwa okanye i-pulsed, ke i-spatial suppressor ingasetyenziselwa ukuyicinezela, kuba Ukuphazamiseka kungena kwi-eriyali efumanayo ukusuka kumthombo ukusuka kwicala elithile. Ukuba i-zero yepateni ye-eriyali yokufumana i-radiation ibekwe kwicala lomthombo wokuphazamiseka, ukuphazamiseka kuya kucinezelwa. Iinkqubo ezinjalo zibizwa ngokuba yi-adaptive beamforming & beam nulling systems.
Iprothokholi yerediyo isetyenzisiwe. Abavelisi beModem banokusebenzisa umgangatho (WiFi, DVB-T) okanye iprotocol yerediyo yobunini. Le parameter ayifane iboniswe kwiinkcukacha. Ukusetyenziswa kwe-DVB-T kubonakaliswe ngokungangqalanga ngamabhanti aphindaphindiweyo axhaswayo 2/4/6/7/8, ngamanye amaxesha i-10 MHz kunye nokukhankanywa kwisicatshulwa sokucaciswa kwe-COFDM (coded OFDM) iteknoloji apho i-OFDM isetyenziswa ngokubambisana. ngekhowudi engangxoliyo. Ngokudlulayo, siqaphela ukuba i-COFDM sisilogeni sentengiso kwaye ayinanzuzo ngaphezu kwe-OFDM, kuba i-OFDM ngaphandle kwekhowudi ekwaziyo ukumelana nengxolo ingazange isetyenziswe xa isenziwa. Linganisa i-COFDM kunye ne-OFDM xa ubona ezi zishunqulelo kwiinkcukacha zemodem yerediyo.
Iimodem ezisebenzisa iprotocol esemgangathweni zihlala zakhiwe kwisiseko se-chip ekhethekileyo (WiFi, DVB-T) esebenza ngokubambisana ne-microprocessor. Ukusebenzisa itshiphu yesiko kukhulula umenzi wemodem kwiintloko ezininzi ezinxulumene noyilo, umfuziselo, ukuphumeza, kunye nokuvavanya eyakhe iprothokholi yerediyo. I-microprocessor isetyenziselwa ukunika imodem umsebenzi oyimfuneko. Iimodem ezinjalo zineenzuzo ezilandelayo.
- Ixabiso eliphantsi.
- Ubunzima obuhle kunye nobukhulu beeparamitha.
- Ukusetyenziswa kwamandla aphantsi.
Kukwakho nezinto ezingeloncedo.
- Ukungakwazi ukutshintsha iimpawu ze-interface yerediyo ngokutshintsha i-firmware.
- Uzinzo oluphantsi lwezibonelelo kwixesha elide.
- Izakhono ezilinganiselweyo ekuboneleleni ngenkxaso yobugcisa obufanelekileyo xa kusonjululwa iingxaki ezingekho mgangathweni.
Uzinzo oluphantsi lokubonelela ngenxa yokuba abavelisi be-chip bagxininise ngokukodwa kwiimarike ezininzi (iiTV, iikhompyutha, njl.). Abavelisi beemodem zee-UAVs abayinto ephambili kubo kwaye abanako nangayiphi na indlela ukuphembelela isigqibo somenzi we-chip sokuyeka ukuvelisa ngaphandle kokutshintshwa okwaneleyo kwenye imveliso. Eli nqaku liqiniswa yindlela yokupakisha ujongano lukanomathotholo kwii-microcircuits ezikhethekileyo ezifana "nenkqubo kwi-chip" (Inkqubo kwiChip-SoC), kwaye ke iitshiphusi zojongano lukanomathotholo zihlanjwa kancinci kancinci kwimakethi ye-semiconductor.
Izakhono ezinqongopheleyo ekuboneleleni ngenkxaso yobugcisa zibangelwa kukuba amaqela ophuhliso eemodem asekelwe kwiprothokholi yerediyo eqhelekileyo inabasebenzi abafanelekileyo abaneengcali, ngokuyintloko kwi-electronics kunye ne-microwave technology. Kusenokungabikho kwaphela iingcaphephe zonxibelelwano koonomathotholo apho, kuba akukho zingxaki banokuzisombulula. Ke ngoko, abavelisi be-UAV abajonga izisombululo kwiingxaki zonxibelelwano lukanomathotholo olungeyomfuneko banokuzifumana bephoxekile malunga nokubonisana kunye noncedo lobugcisa.
Iimodem ezisebenzisa iprotocol yerediyo yobunini zakhiwe ngokwesiseko se-analog yendalo yonke kunye neechips zokusetyenzwa komqondiso wedijithali. Uzinzo lonikezelo lweechips ezinjalo luphezulu kakhulu. Enyanisweni, ixabiso likwaphezulu. Iimodem ezinjalo zineenzuzo ezilandelayo.
- Amathuba amaninzi okulungelelanisa imodem kwiimfuno zomthengi, kubandakanywa ukulungelelanisa i-interface yerediyo ngokuguqula i-firmware.
- Izakhono ezongezelelweyo zojongano lwerediyo ezinomdla wokusetyenziswa kwii-UAVs kwaye azikho kwiimodem ezakhiwe ngokwesiseko semigaqo yerediyo eqhelekileyo.
- Uzinzo oluphezulu lwezibonelelo, kubandakanywa. kwixesha elide.
- Inqanaba eliphezulu lenkxaso yobugcisa, kubandakanywa nokusombulula iingxaki ezingekho mgangathweni.
Iziphene.
- Ixabiso eliphezulu.
- Ubunzima kunye nobungakanani beeparamitha zinokuba mbi ngakumbi kunezo zeemodem zisebenzisa iiprothokholi zerediyo eziqhelekileyo.
- Ukusetyenziswa kwamandla okongeziweyo kweyunithi yokucwangcisa umqondiso wedijithali.
Idatha yobuchwephesha kwezinye iimodem zeeUAVs
Itheyibhile ibonisa iiparitha zobugcisa zezinye iimodem zee-UAV ezikhoyo kwimarike.
Qaphela ukuba nangona imodem ye-3D Link inamandla okuhambisa asezantsi xa kuthelekiswa nePicoradio OEM kunye neemodem ze-J11 (25 dBm vs. 27−30 dBm), uhlahlo lwabiwo-mali lwamandla e-3D Link luphezulu kunezo modem ngenxa yovakalelo oluphezulu lomamkeli (kunye isantya esifanayo sogqithiso lwedatha kwiimodem ezithelekisiweyo). Ngaloo ndlela, uluhlu lonxibelelwano xa usebenzisa i-3D Link luya kuba lukhulu kunye ne-stealth yamandla engcono.
Itheyibhile. Idatha yobuchwephesha kwezinye iimodem zebroadband zee-UAVs kunye neerobhothi
IParamu
(yenziwe kwimodyuli ukusuka kwiMicrohard)
(bona kwakho )
Umenzi, ilizwe
Geoscan, RF
Mobilicom, Israel
I-Airborne Innovations, eCanada
DTC, UK
Redess, eTshayina
Uluhlu lonxibelelwano [km] 20−60
5
n / A*
n / A*
I-10 − 20
Isantya [Mbit/s] 0.023−64.9
I-1.6 − 6
I-0.78 − 28
I-0.144 − 31.668
I-1.5 − 6
Ukulibaziseka kokuhanjiswa kwedatha [ms] 1−20
25
n / A*
I-15 − 100
I-15 − 30
Imilinganiselo yeyunithi ekwibhodi LxWxH [mm] 77x45x25
74x54x26
40x40x10 (ngaphandle kwendlu)
67x68x22
76x48x20
Ubunzima beyunithi ebhodini [igram] 89
105
17.6 (ngaphandle kwezindlu)
135
88
Unxibelelwano lolwazi
Ethernet, RS232, CAN, USB
I-Ethernet, i-RS232, i-USB (ukhetho)
Ethernet, RS232/UART
HDMI, AV, RS232, USB
HDMI, Ethernet, UART
Umbane weyunithi ekwibhodi [Volt/Watt] 7−30/6.7
7−26/n/a*
5−58/4.8
5.9−17.8/4.5−7
7−18/8
Umbane weyunithi ephantsi [iVolt/Watt] 18−75 okanye iPoE/7
7−26/n/a*
5−58/4.8
6−16/8
7−18/5
Amandla okuhambisa [dBm] 25
n / A*
I-27 − 30
20
30
Umamkeli ubuntununtunu [dBm] (ngesantya [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)
Uhlahlo lwabiwo-mali lwamandla emodem [dB] (yesantya [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*
Ubungqina: 127 (1.5) 124 (3.0) 120 (6.0)
Iibhendi zamaza ezixhasiweyo [MHz] 4−20
4.5; Xnumx
2; 4; Xnumx
0.625; I-1.25; 2.5; 6; 7; 8
2; 4; Xnumx
Simplex/duplex
I-Duplex
I-Duplex
I-Duplex
Simplex
I-Duplex
Ukwahluka kwenkxaso
ewe
ewe
ewe
ewe
ewe
Yahlula itshaneli yolawulo/itelemetry
ewe
ewe
ewe
akukho
ewe
Iiprothokholi zolawulo ze-UAV ezixhaswayo kulawulo/kwitshaneli yetelemetry
MAVLink, ubunini
MAVLink, ubunini
akukho
akukho
Ikhonkco le-MAV
Inkxaso ye-Multiplexing kulawulo / kwitshaneli yetelemetry
ewe
ewe
akukho
akukho
n / A*
Ii-topology zenethiwekhi
I-PTP, i-PMP, i-relay
I-PTP, i-PMP, i-relay
I-PTP, i-PMP, i-relay
PTP
I-PTP, i-PMP, i-relay
Iindlela zokwandisa ukugonywa kwengxolo
I-DSSS, i-narrowband kunye ne-pulse suppressors
n / A*
n / A*
n / A*
n / A*
Iprothokholi yerediyo
yobunini
n / A*
n / A*
I-DVB-T
n / A*
* n/a - akukho datha.
Malunga nombhali
Alexander Smorodinov[imeyile ikhuselwe]] yingcaphephe ekhokelayo kwi-Geoscan LLC kwicandelo lonxibelelwano olungenazingcingo. Ukusukela ngo-2011 ukuza kuthi ga ngoku, ebephuhlisa iiprothokholi zikanomathotholo kunye ne-algorithms yokusetyenzwa kwemiqondiso yemodem yerediyo ye-broadband ngeenjongo ezahlukeneyo, kunye nokuphumeza i-algorithms ephuhlisiwe esekwe kwiitshiphu ezicwangcisiweyo. Imimandla enomdla yombhali ibandakanya uphuhliso lwe-algorithms yongqamaniso, uqikelelo lwepropathi yetshaneli, ukumodareyitha / ukuthotywa kwemodyuli, ikhowudi yokumelana nengxolo, kunye nezinye iindlela zokufikelela kwimidiya (MAC) algorithms. Ngaphambi kokujoyina iGeoscan, umbhali wasebenza kwimibutho eyahlukeneyo, ephuhlisa izixhobo zonxibelelwano ezingenazingcingo. Ukususela ngo-2002 ukuya ku-2007, wasebenza eProteus LLC njengengcali ekhokelayo kuphuhliso lweenkqubo zonxibelelwano ezisekelwe kumgangatho we-IEEE802.16 (WiMAX). Ukususela kwi-1999 ukuya kwi-2002, umbhali wayebandakanyekile ekuphuhliseni i-algorithms yokurekhoda i-coding-resistant kunye nemodeli yeendlela ze-radio link kwi-Federal State Unitary Enterprise Central Research Institute "Granit". Umbhali ufumene i-Candidate ye-Technical Sciences degree kwi-St. Petersburg University of Aerospace Instrumentation ngo-1998 kunye ne-Radio Engineering degree kwi-yunivesithi efanayo kwi-1995. UAlexander ulilungu langoku le-IEEE kunye noMbutho woNxibelelwano we-IEEE.
umthombo: www.habr.com