Mer: Ikigereranyo cya modulation, nikigereranyo cyagaciro keza ka vector ubunini bwikosa ryimbeba (igipimo cya kare yubunini bwa vector nziza kuri square vector vector vector vector vector vector vector. Nimwe mubipimo ngenderwaho kugirango bipime ubuziranenge bwibimenyetso bya TV. Ni ngombwa cyane kubipimo bya logatithic ibisubizo byibigo bigoreka byari birenze ibimenyetso bya Digital. Irasa nicyerekezo-kuri-urusaku cyangwa abatwara urusaku rwikigereranyo cyakoreshejwe muri sisitemu ya analog. Nibikorwa byurubanza igice cyo kunanirwa kwihanganira. Ibindi bipimo bisa nkibipimo bya BER biti, C / N in-urusaku, urwego rwimari, igishushanyo mbonera, igishushanyo mbonera, nibindi.
Agaciro k'ibicuruzwa bigaragazwa muri DB, kandi nini agaciro ka mer, nibyiza ubuziranenge. Ikimenyetso cyiza, cyegereje ibimenyetso byagushutswe ni umwanya mwiza, naho ubundi. Ibizamini byikizamini byerekana ubushobozi bwanditse bwa digitale kugirango ugarure numero ya binary, kandi hari ibimenyetso bifatika-kuri-urusaku (s / n) bisa nigimenyetso cya baseband. Ikimenyetso cya Qam-cyahinduwe kiva imbere yimbere winjize murugo unyuze kumurongo. Mer Nerekana bizagenda byiyongera buhoro buhoro. Mugihe c'inyenyeri 64qam, impyisi yo mu rwego rwo hejuru ya mexi ni 23.5DB, kandi muri 256qam (ibisohoka hejuru ya 34DB, birashobora kwemeza ko icya kabiri kibanziriza uko byateguwe na 34DB. Niba ari munsi yagaciro, igishushanyo c'imbaguro ntirishobora gufungwa. MER indicator front-end modulation output requirements: For 64/256QAM, front-end > 38dB, sub-front-end > 36dB, optical node > 34dB, amplifier > 34dB (secondary is 33dB), user end > 31dB (secondary is 33dB), above 5 A key MER point is also often used to find cable TV line problems.
Akamaro ka Mer Mer, ifatwa nkuburyo bwo gupima snr, kandi ibisobanuro bya mer ni:
①. Harimo ibintu bitandukanye byangiza ibimenyetso: urusaku, abatwara imyambaro, iq amplitude ubusumbane, hamwe nicyiciro cyicyiciro.
②. Irerekana ubushobozi bwimikorere ya digitale yo kugarura imibare ibiri; Irerekana urwego rwangiza ibimenyetso bya televiziyo nyuma yoherezwa binyuze murusobe.
③. SNR ni parameter parand, kandi mer ni ibipimo bya radiyo.
Iyo ibimenyetso byerekana ko ari urwego runaka, ibimenyetso amaherezo bizashyirwa nabi. Muri iki gihe, igipimo cya OISITIKI BYINSHI BER yiyongera. Ber (igipimo cyibiti): Igipimo cya Bit Igipimo, gisobanurwa nkigipimo cyumubare wamakosa bits hamwe numubare rusange wa bits. Kubimenyetso bya binary digitale, kuva binini bits zanduzwa, igipimo cyibiti biti byitwa igipimo cyamakosa (ber).
Ber = ikosa biti igipimo / igipimo cyose.
Ber muri rusange agaragazwa mubisobanuro bya siyansi, na ber yo hepfo, nibyiza. Iyo ireme ryikimenyetso ari ryiza cyane, indangagaciro za ber mbere na nyuma yo gukosora ni bimwe; Ariko mugihe cyo kwivanga runaka, indangagaciro za ber mbere na nyuma yo gukosora biratandukanye, kandi nyuma yo gukosora ibipimo biti biti bigufi. Iyo ikosa rito ari 2 × 10-4, Mosaic igice cyihariye, ariko irashobora kurebwa; Ber ikomeye ni 1 × 10-4, umubare munini wa mosaika ugaragara, kandi gukina ishusho bigaragara ko ari hafi; Ber arenze 1 × 10-3 ntishobora kurebwa na gato. Reba. Ironderero rya ber rifite agaciro kamwe gusa kandi ntigaragaza neza imiterere yibikoresho byose. Rimwe na rimwe, biterwa gusa no kwiyongera gutunguranye kubera kwivanga ako kanya, mugihe amakosa ari ahateganye rwose. Inzira yose irashobora gukoreshwa nkigisesengura cyamakosa. Kubwibyo, amakosa arashobora gutanga umuburo hakiri kare ibimenyetso. Iyo ubuziranenge bwikimenyetso igabanuka, nzagabanuka. Hamwe no kwiyongera kwurusaku no kwivanga kurwego runaka, mer izagabanuka buhoro buhoro, mugihe BER idahindutse. Gusa mugihe kwivanga ku rugero runaka, mer Ikigo gitangira kwangirika mugihe mer yataye ubudahwema. Iyo mer yataye kurwego rwibanze, ber izamanuka cyane.
Igihe cyagenwe: Gashyantare-23-2023