Kodi mitundu ya ulusi wa SDM air-division multiplexing ndi iti?

Mu kafukufuku ndi chitukuko cha ukadaulo watsopano wa ulusi wa kuwala, kugawa kwa SDM space division multiplexing kwakopa chidwi chachikulu. Pali njira ziwiri zazikulu zogwiritsira ntchito SDM mu ulusi wa kuwala: kugawa kwapakati (CDM), komwe kutumiza kumachitika kudzera pakati pa ulusi wa multi-core optical. Kapena Mode Division Multiplexing (MDM), yomwe imafalitsa kudzera mu njira zofalitsira za ulusi wa mode ochepa kapena multi-mode.

Ulusi wa Core Division Multiplexing (CDM) kwenikweni umachokera pakugwiritsa ntchito njira ziwiri zazikulu.

Choyamba chimachokera pa kugwiritsa ntchito ma single-core fiber bundles (ma fiber ribbons), momwe ma parallel single-mode fibers amalumikizidwa pamodzi kuti apange ma fiber bundles kapena ma ribbons omwe angapereke maulalo okwana mazana ambiri ofanana.

Njira yachiwiri imachokera pa kutumiza deta kudzera pa core imodzi (mode imodzi pa core) yomwe ili mu ulusi womwewo, mwachitsanzo mu ulusi wa MCF multicore. Core iliyonse imaonedwa ngati njira imodzi yosiyana.

Ulusi wa MDM (Module Division Multiplexing) umatanthauza kutumiza deta pamitundu yosiyanasiyana ya ulusi wowala, womwe uliwonse ukhoza kuonedwa ngati njira yosiyana.

Mitundu iwiri yodziwika bwino ya MDM ndi multimode fiber (MMF) ndi fractional mode fiber (FMF). Kusiyana kwakukulu pakati pa ziwirizi ndi kuchuluka kwa njira (njira zomwe zilipo). Popeza ma MMF amatha kuthandizira mitundu yambiri (makumi a njira), intermodal crosstalk ndi differential mode group delay (DMGD) zimakhala zofunikira.

Palinso ulusi wa kristalo wa photonic (PCF) womwe unganenedwe kuti ndi wa mtundu uwu. Umachokera ku makhalidwe a makristalo a photonic, omwe amaletsa kuwala kudzera mu bandgap effect ndikuwutumiza pogwiritsa ntchito mabowo a mpweya omwe ali m'mbali mwake. PCF imapangidwa makamaka ndi zinthu monga SiO2, As2S3, ndi zina zotero, ndipo mabowo a mpweya amalowetsedwa m'dera lozungulira pakati kuti asinthe kusiyana kwa refractive index pakati pa pakati ndi cladding.

Ulusi wa CDM ukhoza kufotokozedwa ngati kungowonjezera ma cores a ulusi wa single-mode omwe amanyamula chidziwitso, omwe ali mu cladding yomweyo (multi-core fiber MCF kapena single-core fiber bundle). MDM mode division multiplexing ndi kugwiritsa ntchito ma modes angapo a spatial-optical mu transmission medium ngati njira za data za munthu payekha/zosiyana/zodziyimira pawokha, makamaka pa transmission yolumikizidwa mtunda waufupi.