MER: Rabon kuskuren daidaitawa, wanda shine rabon tasirin ƙimar girman vector zuwa ƙimar tasiri na girman kuskure akan zane-zanen taurari (rabon murabba'in girman vector mai kyau zuwa murabba'in girman vector na kuskure). Yana ɗaya daga cikin manyan alamun auna ingancin siginar talabijin na dijital. Yana da matuƙar mahimmanci ga sakamakon auna logarithmic na karkacewar da aka ɗora akan siginar daidaitawar dijital. Yana kama da rabon sigina-zuwa-amo ko rabon mai ɗauka-zuwa-amo da ake amfani da shi a cikin tsarin analog. Tsarin hukunci ne mai mahimmanci na haƙurin gazawa. Sauran alamu makamantan su kamar ƙimar kuskuren bit na BER, rabon C/N mai ɗauka-zuwa-amo, matsakaicin ƙarfin matakin wuta, zane-zanen taurari, da sauransu.
Ana bayyana ƙimar MER a cikin dB, kuma girman ƙimar MER, ingancin siginar ya fi kyau. Mafi kyawun siginar, mafi kusancin alamomin da aka daidaita zuwa ga matsayin da ya dace, da kuma akasin haka. Sakamakon gwajin MER yana nuna ikon mai karɓar dijital don dawo da lambar binary, kuma akwai rabon sigina-zuwa-amo na gaske (S/N) kama da na siginar baseband. Siginar da aka daidaita QAM tana fitowa daga ƙarshen gaba kuma tana shiga gida ta hanyar hanyar sadarwa. Alamar MER za ta lalace a hankali. A cikin yanayin zane-zanen taurari 64QAM, ƙimar iyakar gwaji na MER shine 23.5dB, kuma a cikin 256QAM shine 28.5dB (fitowar gaba yakamata ta kasance Idan ta fi 34dB girma, tana iya tabbatar da cewa siginar ta shiga gida yadda ya kamata, amma ba ta kawar da rashin daidaituwar da ingancin kebul na watsawa ko ƙarshen gaba ke haifarwa ba). Idan ya yi ƙasa da wannan ƙimar, ba za a kulle zane-zanen taurari ba. Bukatun fitarwa na alamar MER na gaba-gaba na daidaitawa: Don 64/256QAM, gaba-gaba > 38dB, ƙasa-ƙasa-gaba > 36dB, na'urar gani > 34dB, amplifier > 34dB (na biyu shine 33dB), ƙarshen mai amfani > 31dB (na biyu shine 33dB), sama da 5 Ana amfani da maɓallin MER mai mahimmanci don nemo matsalolin layin talabijin na kebul.
Ana ɗaukar mahimmancin MER MER a matsayin nau'in ma'aunin SNR, kuma ma'anar MER ita ce:
①. Ya haɗa da nau'ikan lalacewa daban-daban ga siginar: hayaniya, zubar da ruwa daga mai ɗaukar kaya, rashin daidaiton girman IQ, da hayaniyar mataki.
②. Yana nuna ikon ayyukan dijital na dawo da lambobin binary; yana nuna matakin lalacewar siginar talabijin na dijital bayan an watsa ta hanyar hanyar sadarwa.
③. SNR sigar baseband ce, kuma MER sigar mitar rediyo ce.
Idan ingancin siginar ya ragu zuwa wani mataki, daga ƙarshe za a fassara alamomin ba daidai ba. A wannan lokacin, ainihin ƙimar kuskuren bit ɗin BER yana ƙaruwa. BER (Ƙimar Kuskuren Bit): Ƙimar kuskuren bit, wanda aka ayyana a matsayin rabo na adadin bit ɗin kuskure zuwa jimlar adadin bit. Ga siginar dijital ta binary, tunda ana watsa bit ɗin binary, ƙimar kuskuren bit ɗin ana kiranta ƙimar kuskuren bit ɗin (BER).
BER = Kuskuren Kuɗin Bit/Jimillar Kuɗin Bit.
Gabaɗaya ana bayyana BER a cikin bayanin kimiyya, kuma ƙasa da BER, mafi kyau. Idan ingancin siginar yayi kyau sosai, ƙimar BER kafin da bayan gyaran kuskure iri ɗaya ne; amma idan akwai wani tsangwama, ƙimar BER kafin da bayan gyaran kuskure sun bambanta, kuma bayan gyaran kuskure. Kuskuren bit ɗin ya yi ƙasa. Lokacin da kuskuren bit ɗin ya kasance 2 × 10-4, mosaic na ɓangare yana bayyana lokaci-lokaci, amma har yanzu ana iya ganinsa; BER mai mahimmanci shine 1 × 10-4, adadi mai yawa na mosaics suna bayyana, kuma sake kunna hoton yana bayyana a lokaci-lokaci; BER mafi girma fiye da 1 × 10-3 ba za a iya kallonsa kwata-kwata ba. duba. Ma'aunin BER yana da ƙimar tunani kawai kuma baya nuna cikakken matsayin kayan aikin cibiyar sadarwa gaba ɗaya. Wani lokaci ana haifar da shi ne kawai ta hanyar ƙaruwa kwatsam saboda tsangwama nan take, yayin da MER gaba ɗaya akasin haka ne. Ana iya amfani da dukkan tsarin azaman nazarin kuskuren bayanai. Saboda haka, MER na iya ba da gargaɗi da wuri don sigina. Lokacin da ingancin sigina ya ragu, MER zai ragu. Tare da ƙaruwar hayaniya da tsangwama zuwa wani mataki, MER zai ragu a hankali, yayin da BER ya kasance ba canzawa ba. Sai lokacin da tsangwama ta ƙaru zuwa wani mataki, MER BER zai fara lalacewa lokacin da MER ya ci gaba da raguwa. Lokacin da MER ya faɗi zuwa matakin ƙofa, BER zai faɗi sosai.
Lokacin Saƙo: Fabrairu-23-2023