Gutinda Kwamamaza no Gutinda Skew

Ku banyamwuga benshi b'itumanaho, ibitekerezo nka 'gutinda gukwirakwiza' na 'gutinda skew' bitwibutsa kwibuka ububabare bw'ishuri ryisumbuye rya fiziki.Mubyukuri, ingaruka zo gutinda no gutinda skew zohereza ibimenyetso birasobanurwa byoroshye kandi birasobanuka.

Gutinda ni umutungo uzwiho kubaho kubwoko bwose bwitangazamakuru.Gutinda gukwirakwizwa bihwanye nigihe kingana hagati yigihe ikimenyetso cyatanzwe nigihe cyakiriwe kurundi ruhande rwumuyoboro wa kabili.Ingaruka isa no gutinda mugihe hagati yinkuba ikubiswe ninkuba-usibye ko ibimenyetso byamashanyarazi bigenda byihuse kuruta amajwi.Agaciro nyako ko gutinda kugoretse-kabili ni imikorere yumuvuduko wizina wo gukwirakwiza (NVP), uburebure ninshuro.

NVP iratandukanye ukurikije ibikoresho bya dielectric bikoreshwa mumigozi kandi bigaragazwa nkijanisha ryumuvuduko wurumuri.Kurugero, ibyiciro byinshi 5 polyethylene (FRPE) yubatswe bifite NVP kuva kuri 0.65cto0.70c (aho "c" igereranya umuvuduko wurumuri ~ 3 x108 m / s) iyo upimye kumugozi urangiye.Inyubako ya kabili ya Teflon (FEP) iri hagati ya 0.69cto0.73c, mugihe insinga zakozwe na PVC ziri muri 0.60cto0.64crange.

Indangagaciro za NVP zizagira uruhare mugutinda kwinyongera kuburebure bwatanzwe bwa kabili, nkuko kwiyongera kwuburebure bwanyuma-kurangira bizatera kwiyongera ugereranije gutinda-kurangira.Kimwe nibindi byinshi byohereza, gutinda agaciro ni inshuro zishingiye.

Iyo ibice byinshi mumurongo umwe byerekana imikorere itandukanye yo gutinda, ibisubizo ni gutinda skew.Gutinda skew kugenwa no gupima itandukaniro riri hagati yubukwe hamwe nubukererwe buke hamwe nubukererwe cyane.Ibintu bigira ingaruka kubikorwa byo gutinda skew harimo gutoranya ibintu, nko kubika imiyoboro, hamwe nigishushanyo mbonera, nkibinyuranyo mubipimo bigoretse kuva byombi.

Gutinda gukwirakwiza insinga

Nubwo insinga zose zahinduwe-zigaragaza gutinda skew kurwego runaka, insinga zashizweho muburyo bwitondewe kugirango zemererwe gutandukana muri NVP hamwe nuburebure bwikurikiranya byombi bizagira gutinda byemewe kubisanzwe byujuje imiyoboro ya horizontal.Bimwe mubiranga bishobora kugira ingaruka mbi kubikorwa byo gutinda skew harimo insinga zifite imyubakire idahwitse ya dielectric hamwe nabafite itandukaniro rikabije mubiciro byombi.

Kwamamaza gutinda no gutinza imikorere ya skew bigaragazwa nuburinganire bwakarere kamwe (LAN) kubipimo byimikorere mibi 100 mchannel kugirango hamenyekane neza ibimenyetso.Ibibazo byoherejwe bijyana no gutinda cyane no gutinda skew harimo kwiyongera kwa jitter hamwe nigipimo cyamakosa.Ukurikije ibisobanuro bya IEEE 802 byuruhererekane rwa LAN, gutinda gukwirakwizwa kwa 570 ns / 100mat 1 MHz hamwe nubukererwe ntarengwa bwa 45ns / 100mup kugeza 100 MHz birasuzumwa na TIA kumurongo wa 3, 4 na 5, insinga 4.Itsinda rishinzwe imirimo ya TIA TR41.8.1 riratekereza kandi ku iterambere ryibisabwa kugirango harebwe gutinda gukwirakwizwa no gutinda skew kumirongo 100 ya ohm itambitse hamwe numuyoboro wubatswe hakurikijwe ANSI / TIA / EIA-568-A.Bitewe na komite ya TIA “Ibaruwa itora” TR-41: 94-4 (PN-3772) hafashwe umwanzuro mu nama yo muri Nzeri 1996 gutanga “Amatora y’inganda” ku mushinga wavuguruwe mbere yo kurekurwa.Biracyakemutse nikibazo cyo kumenya niba ibyiciro byateganijwe bizahinduka (urugero, icyiciro 5.1), kugirango bigaragaze itandukaniro riri hagati yinsinga zapimwe kubindi byadindije / gutinda skew ibisabwa, nibitari byo.

Nubwo gutinda gukwirakwizwa no gutinda skew byitabwaho cyane, ni ngombwa kumenya ko ikibazo cyingenzi cyibikorwa bya cabling kubikorwa byinshi bya LAN bisigaye bikomeza kuba igipimo cyambukiranya imipaka (ACR).Mugihe marike ya ACR itezimbere ibimenyetso byerekana urusaku bityo bikagabanya kugaragara kwamakosa ya biti, imikorere ya sisitemu ntabwo ihindurwa cyane numuyoboro wa kabine hamwe nubukererwe bukabije.Kurugero, 15 ns gutinda skew kumuyoboro wa cabling mubisanzwe ntabwo bizavamo imikorere myiza yumurongo urenze 45 ns, kuri sisitemu yagenewe kwihanganira kugera kuri 50 ns yo gutinda skew.

Kubera iyo mpamvu, gukoresha insinga zifite ubukererwe bukomeye bwa skew marge bifite agaciro kanini kubwishingizi batanga kubikorwa byo kwishyiriraho cyangwa izindi mpamvu zishobora gutuma ubundi gutinda kurenga imipaka, aho gusezerana imikorere myiza ya sisitemu ugereranije numuyoboro ko gusa yujuje sisitemu itinda skew imipaka na nanosekond nyinshi.

Kuberako insinga zikoresha ibikoresho bitandukanye bya dielectric kubintu bibiri byombi byagaragaye ko bitera ibibazo hamwe no gutinda gutinda, haherutse kuvugwa impaka zo gukoresha ibikoresho bivanze bya dielectric mukubaka insinga.Amagambo nka "2 kuri 2 ″ (umugozi ufite ibice bibiri bifite ibikoresho bya dielectric" A "na babiri babiri bafite ibikoresho" B ") cyangwa" 4 kuri 0 ″ (umugozi ufite ibice bine byose bikozwe mubintu A, cyangwa ibikoresho B ) byerekana ibiti kuruta insinga, rimwe na rimwe bikoreshwa mugusobanura kubaka dielectric.

Nubwo impuha zubucuruzi zishobora kuyobya umuntu kwizera ko gusa inyubako zifite ubwoko bumwe bwibikoresho bya dielectric bizagaragaza imikorere yemewe yo gutinda skew, ikigaragara nuko insinga zateguwe neza zifite ibikoresho bya dielectric, cyangwa ibikoresho byinshi bya dielectric bifite ubushobozi buke bwo guhaza ndetse nu umuyoboro munini cyane utinda skew ibisabwa byerekanwe nibisabwa hamwe nibisuzumwa na TIA.

Mubihe bimwe, inyubako zivanze za dielectric zirashobora no gukoreshwa muguhagarika gutinda skew itandukana biva kubiciro bitandukanye.Igishushanyo cya 1 nicya 2 byerekana gutinda guhagararirwa hamwe nindangagaciro za skew zabonetse muburyo bwa metero 100 bwatoranijwe bwa kabili ifite "2 kuri 2 ″ (FRPE / FEP).Menya ko gukwirakwiza kwinshi gutinda no gutinda skew kuriyi sample ni 511 ns / 100mand 34 ns, muburyo bwa interineti kuva kuri 1 MHz kugeza 100 MHz.