Hoʻomaka i ka noi ʻana o RF optical transmission RF ma luna o Fiber

Hoʻolauna i ka noi oʻO ka hoʻoili ʻana o RF opticalRF ma luna o ka Fiber

I nā makahiki i hala iho nei, ua ulu wikiwiki ke kamaʻilio microwave a me ka ʻenehana kelepona ʻike. Ua holomua nui nā ʻenehana ʻelua i kā lākou mau kula, a ua alakaʻi pū i ka hoʻomohala wikiwiki ʻana o nā lawelawe kelepona kelepona a me nā lawelawe hoʻouna ʻikepili, e lawe mai ana i ka ʻoluʻolu nui i ke ola o ka poʻe. ʻO nā ʻenehana ʻelua o ka kamaʻilio microwave a me ke kamaʻilio photoelectric i kā lākou pono ponoʻī, akā loaʻa iā lākou kekahi mau hemahema ʻaʻole hiki ke lanakila. Pono ka hoʻoili ʻana o Photoelectric i ka ʻupena kino, a aia kekahi mau hemahema i ka maʻalahi, ka ʻoihana wikiwiki a me ka neʻe ʻana o ke kūkulu ʻana. Loaʻa i ka kamaʻilio Microwave kekahi mau hemahema i ka hoʻouna ʻana i kahi lōʻihi a me ka nui nui, a pono ka microwave i ka hoʻonui pinepine ʻana i ka relay a me ka hoʻouna hou ʻana, a ua kaupalena ʻia ka bandwidth hoʻouna e ka alapine lawe. Ua alakaʻi kēia i ka hoʻohui ʻana o ka microwave a me ka optical Fiber transmission technology, ʻo ia hoʻi, ʻenehana Radio over Fiber (ROF), i kapa pinepine ʻia ʻo ia.RF ma luna o ka Fiber, a i ʻole ka ʻenehana mamao alapine radio. ʻO ka māhele nui loa o RF ma luna o ka ʻenehana Fiber ʻo ia ke kahua o ka kamaʻilio fiber optical, e komo pū ana me nā kahua kahua paʻa kelepona, nā ʻōnaehana puʻupuʻu, broadband uea, TV kelepona, kamaʻilio pūnaewele pilikino a pēlā aku. I nā makahiki i hala iho nei, me ka piʻi ʻana o nā photonics microwave, ua hoʻohana nui ʻia ʻo RF over Fiber ʻenehana i ka microwave photon radar, kamaʻilio UAV, noiʻi astronomy a me nā kula ʻē aʻe. Wahi a nā ʻano like ʻole o ka modulation laser, hiki ke hoʻokaʻawale ʻia ke kamaʻilio laser i loko o ka modulation kūloko a me ka modulation o waho, ʻo ka mea maʻamau ka modulation o waho, a ʻo ka RF ma luna o ka Fiber e pili ana i ka modulation laser waho i wehewehe ʻia ma kēia pepa. ʻO RF ma luna o nā loulou Fiber ka mea nui o ka transceiver optical, transmission, aNā loulou ROF, e like me ka hōʻike ʻana ma ke kiʻi aʻe:

ʻO kahi hoʻolauna pōkole i ka māhele māmā. Hoʻohana mau ʻia ʻo LDDFB lasers(ʻano manaʻo manaʻo i hāʻawi ʻia), i hoʻohana ʻia no ka leo haʻahaʻa, nā noi kiʻekiʻe dynamic range, a me nā lasers FP (Fabry-Perot type) i hoʻohana ʻia no nā noi liʻiliʻi. ʻO 1064nm a me 1550nm nā lōʻihi nalu maʻamau. ʻO ka PD hemea nānā kiʻi, a ma ka ʻaoʻao ʻē aʻe o ka loulou fiber optic, ʻike ʻia ke kukui e ka PIN photodiode o ka mea hoʻokipa, nāna e hoʻohuli i ke kukui i hōʻailona uila a laila i ke kaʻina hana uila maʻamau. ʻO ka fiber optical i hoʻohana ʻia no ka pilina waena, ʻo ia ka fiber optical mode hoʻokahi a me multi-mode. Hoʻohana mau ʻia ka fiber mode-hoʻokahi i ka ʻupena iwi kuamoʻo ma muli o kona haʻahaʻa haʻahaʻa a me ka liʻiliʻi o ka poho. Loaʻa i ka multimode fiber kekahi noi ma ka pūnaewele wahi kūloko no ka mea he maʻalahi ke hana a hiki ke hoʻokipa i nā hoʻouna he nui i ka manawa like. ʻO ka attenuation o ka hōʻailona optical i ka fiber he liʻiliʻi loa, ~ 0.25dB / km wale nō ma 1550nm.

Ma muli o nā hiʻohiʻona o ka linear transmission a me ka optical transmission, loaʻa i nā loulou ROF nā pono ʻenehana penei:

• Haʻahaʻa loa poho, fiber attenuation emi ma mua o 0.4 dB/km

• Ka hoʻouna ʻana i ka fiber ultra-bandwidth, ka nalowale o ka fiber me ke alapine

• Hoʻohui me ka hiki ke lawe i ka hōʻailona kiʻekiʻe a hiki i ka 110GHz• Ke kūʻē ʻana o ka Electromagnetic Interference (EMI) (ʻaʻole pili ka wā ʻino i ka hōʻailona)

• 'O ke kumu kū'ai ha'aha'a no ka mika • 'Oi aku ka ma'alahi a me ke kaumaha o ka fiber, ma kahi o 1/25 o ke alaka'i nalu a me 1/10 o ke kaula coaxial.

• Hoʻonohonoho maʻalahi a maʻalahi o nā modulators electro-optic (no nā ʻōnaehana kiʻi olakino a me nā mīkini)