Sadarwar dijital mara waya: Ka'idar aiki ta daidaita IQ

Sadarwar dijital mara waya: Ka'idar aikiDaidaita IQ
Tsarin IQ shine tushen hanyoyin daidaitawa masu girma daban-daban da ake amfani da su sosai a cikin filayen LTE da WiFi, kamar BPSK, QPSK, QAM16, QAM64, QAM256, da sauransu. Fahimtar ƙa'idar aiki na tsarin daidaitawa na IQ yana da mahimmanci don fahimtar tsarin aiwatar da OFDM a cikin LTE da WiFi. Saboda hanyoyin daidaitawa da ake amfani da su akan kowane ƙaramin mai ɗaukar kaya na OFDM har yanzu dabarun daidaitawa na QAM ne daban-daban bisa ga tsarin daidaitawa na IQ, kuma a zahiri, aiwatar da OFDM shine haɗin tsarin daidaitawa na IQ akan ƙananan masu ɗaukar kaya da yawa.
Ma'anonin I da Q a cikin daidaitawar IQ sun yi daidai da gajerun kalmomin Ingilishi guda biyu: A cikin Mataki da Quadrature, bi da bi. Kawai idan aka yi la'akari da ma'anar zahiri, sunayen siginar I da Q ba su da ma'ana. Menene a cikin mataki? Menene orthogonality? Wane sigina ake amfani da shi azaman nuni don tantance in-lokacida kuma quadrature? A aikace, galibi ana amfani da saitin raƙuman cosine da sine masu mita ɗaya azaman siginar I da Q. Saboda haka, siginar cosine da aka yi amfani da ita azaman siginar I a zahiri siginar tunani ce, wacce ba shakka siginar In Phase ce. Siginar cosine wacce take digiri 90 daga mataki tare da siginar I a zahiri siginar Quadrature ce. Don haka fahimtar siginar daidaitawa ta IQ ita ce a yi la'akari da siginar I azaman siginar ɗaukar cosine, da siginar Q a matsayin siginar ɗaukar sine mai bambancin mita na digiri 90 daga siginar I.

Abin da ake kira gyaran IQ shine amfani da saitin siginar I, wato siginar cosine, da siginar Q, wato siginar sine (tare da bambancin mataki na digiri 90 da kuma orthogonal ga juna) na mita ɗaya da masu ɗaukar kaya, don daidaita siginar baseband guda biyu zuwa ga masu ɗaukar kaya guda biyu a lokaci guda, sannan a haɗa siginar guda biyu da aka daidaita tare a watsa su ta hanyar da'irar RF. Bayan karɓar siginar mitar rediyo, ƙarshen karɓa yana aiki.Rashin daidaituwar IQA lokacin rage girman IQ, saboda masu ɗaukar nauyin guda biyu suna da daidaito da juna, ana iya raba siginar tushe guda biyu daga siginar gauraya bisa ga siginar mai ɗaukar nauyin I da Q da aka yi amfani da su a cikin tsarin daidaitawa na baya kuma a rage girman su daban. Ga siginar I da Q da IQ ta daidaita, ƙara girman gefen ɗaya ba wai kawai yana ƙara girman siginar da aka daidaita ba, har ma yana sa matakin siginar da aka daidaita ya canza zuwa gefe tare da ƙaruwar girma. Don haka a zahiri, daidaita IQ shine daidaita girman da aka yi akan siginar I da siginar Q, amma sakamakon daidaitawa ba wai kawai yana shafar girman siginar da aka daidaita ba, har ma da canjin yanayinsa. Wannan shine babban ƙa'idar aiki na daidaitawa da rage girman IQ.