MER: Chiyero chekukanganisa kwemodulation, chinova chiyero chekukosha kwemhedzisiro yehukuru hwevector kusvika pamhedzisiro yehukuru hwemhedzisiro padhayagiramu yeconstellation (chiyero chechikwere chehukuru hwevector chaiyo kusvika pachikwere chehukuru hwemhedzisiro yemhedzisiro yemodulation). Chimwe chezviratidzo zvikuru zvekuyera mhando yemasaini eTV edhijitari. Zvakakosha zvikuru kumhedzisiro yekuyera kwelogarithmic yekukanganiswa kwakaiswa pamusoro pechiratidzo chemodulation yedhijitari. Zvakafanana nechiyero chesignal-to-noise kana chiyero checarrier-to-noise chinoshandiswa mu analog system. Isystem yekutonga Chikamu chakakosha chekushivirira kukundikana. Zvimwe zviratidzo zvakafanana zvakaita seBER bit error rate, chiyero cheC/N carrier-to-noise, simba repakati pesimba, dhayagiramu yenyeredzi, nezvimwewo.
Kukosha kweMER kunoonekwa mu dB, uye kukosha kweMER kukuru, kunaka kwechiratidzo kuri nani. Kana chiratidzo chave nani, zviratidzo zvakagadziriswa zviri pedyo nenzvimbo yakakodzera, uye zvinopesana. Mhedzisiro yekuyedza yeMER inoratidza kugona kwemugamuchiri wedhijitari kudzoreredza nhamba yebinary, uye pane chiyero chechiratidzo-kune-ruzha (S/N) chakafanana nechechiratidzo chebaseband. Chiratidzo cheQAM-modulated chinobuda kubva kumberi uye chinopinda mumba kuburikidza nenetwork yekupinda. Chiratidzo cheMER chichaderera zvishoma nezvishoma. Panyaya yedhayagiramu yenyeredzi 64QAM, kukosha kweMER kwe empirical threshold kweMER i23.5dB, uye mu256QAM i28.5dB (kubuda kwemberi-kumberi kunofanira kunge kuri Kana yakakwira kupfuura 34dB, inogona kuve nechokwadi chekuti chiratidzo chinopinda mumba zvakajairika, asi hazvibvisi kusagadzikana kunokonzerwa nemhando yetambo yekutumira kana sub-front end). Kana iri pasi peiyi kukosha, dhayagiramu yenyeredzi haizokiyiwi. Zvinodiwa zveMER indicator front-end modulation output: Kune 64/256QAM, front-end > 38dB, sub-front-end > 36dB, optical node > 34dB, amplifier > 34dB (secondary i33dB), user end > 31dB (secondary i33dB), pamusoro pe5. Chinhu chikuru cheMER chinowanzoshandiswawo kuwana matambudziko etambo dzeTV.
Kukosha kweMER MER kunoonekwa senzira yekuyera SNR, uye zvinoreva MER ndeizvi:
①. Inosanganisira mhando dzakasiyana dzekukuvara kwechiratidzo: ruzha, kubuda kwemhepo kubva mumotokari, kusawirirana kweIQ amplitude, uye ruzha rwechikamu.
②. Inoratidza kugona kwemabasa edhijitari kudzoreredza nhamba dzebhinari; inoratidza mwero wekukuvadzwa kwemasaini eTV edhijitari mushure mekutumirwa kuburikidza netiweki.
③. SNR iparameter yebaseband, uye MER iparameter yeredhiyo.
Kana hunhu hwechiratidzo hukadzikira kusvika padanho rakati, zviratidzo zvinozopedzisira zvanyorwa zvisirizvo. Panguva ino, chiyero chechokwadi che bit error BER chinowedzera. BER (Bit Error Rate): Chiyero cheBit error, chinotsanangurwa sechiyero chehuwandu hwemabhiti ekukanganisa kune huwandu hwemabhiti ese. Kune mabhiti edhijitari ebhinari, sezvo mabhiti ebhinari achitumirwa, chiyero chebit error chinonzi bit error rate (BER).
BER = Chiyero cheBit Rate/Bhiti Yese YeBit.
BER inowanzo ratidzwa muzvinyorwa zvesainzi, uye kana BER yakaderera, zviri nani. Kana hunhu hwechiratidzo hwakanaka kwazvo, hunhu hweBER usati wagadzirisa uye mushure mekukanganisa hwakafanana; asi kana paine kupindirana kwakati, hunhu hweBER usati wagadzirisa uye mushure mekukanganisa hwakasiyana, uye mushure mekukanganisa mwero wekukanganisa kwebit wakaderera. Kana kukanganisa kwebit kuri 2×10-4, chikamu chemosaic chinoonekwa dzimwe nguva, asi chinogona kuonekwa; BER yakakosha iri 1×10-4, nhamba huru yemosaics inoonekwa, uye kutamba kwemufananidzo kunoonekwa nguva nenguva; BER yakakura kupfuura 1×10-3 haigone kuonekwa zvachose. tarisa. BER index ingori yereferensi chete uye hairatidze zvizere mamiriro emidziyo yese yenetwork. Dzimwe nguva inokonzerwa nekuwedzera kamwe kamwe nekuda kwekupindirana ipapo ipapo, nepo MER iri yakapesana zvachose. Maitiro ese anogona kushandiswa sekuongorora kukanganisa kwedata. Naizvozvo, MER inogona kupa yambiro yekutanga yezviratidzo. Kana hunhu hwechiratidzo hwadzikira, MER ichadzikira. Nekuwedzera kweruzha nekupindira kusvika pamwero wakati, MER ichadzikira zvishoma nezvishoma, nepo BER ichiramba isina kuchinja. Kana kupindira kwacho kwawedzera kusvika pamwero wakati, MER. BER inotanga kuipa kana MER ichidonha nguva dzose. Kana MER ichidonha kusvika padanho repakati, BER inodonha zvakanyanya.
Nguva yekutumira: Kukadzi-23-2023