Ukuxhumana kwedijithali okungenantambo: Isimiso sokusebenza sokuguqulwa kwe-IQ

Ukuxhumana kwedijithali okungenantambo: Isimiso sokusebenzaUkuguqulwa kwe-IQ
Ukuguqulwa kwe-IQ kuyisisekelo sezindlela ezahlukene zokuguqulwa kwe-high-order ezisetshenziswa kabanzi emikhakheni ye-LTE ne-WiFi, njenge-BPSK, QPSK, QAM16, QAM64, QAM256, njll. Ukuqonda isimiso sokusebenza sokuguqulwa kwe-IQ kubalulekile ukuze kuqondwe kangcono indlela eyisisekelo yokusebenzisa i-OFDM ku-LTE naku-WiFi. Ngoba izindlela zokuguqulwa ezisetshenziswa ku-subcarrier ngayinye ye-OFDM ziseyizindlela ezahlukene zokuguqulwa kwe-QAM ezisekelwe ekuguqulweni kwe-IQ, futhi ngokuyisisekelo, ukusetshenziswa kwe-OFDM kuyindlela yokuguqulwa kwe-IQ kuma-subcarrier amaningi angama-orthogonal.
Imibono ka-I no-Q ekuguqulweni kwe-IQ ihambisana nezifinyezo zamagama amabili esiNgisi: Esigabeni nase-Quadrature, ngokulandelana. Uma sikhuluma ngencazelo engokoqobo, amagama ezimpawu zika-I no-Q awanancazelo. Kuyini isigaba? Kuyini ukulingana? Yisiphi isignali esisetshenziswa njengereferensi yokunquma isigaba.isigabakanye ne-quadrature? Ekusetshenzisweni okusebenzayo, isethi yamagagasi e-cosine kanye ne-sine emvamisa efanayo ngokuvamile asetshenziswa njengezibonakaliso ze-I kanye ne-Q. Ngakho-ke, isignali ye-cosine esetshenziswa njengesignali ye-I empeleni iyisignali yokubhekisela, okuyiyona ngempela isignali ye-In Phase. Isignali ye-cosine engama-degrees angu-90 ngaphandle kwesigaba nesignali ye-I ngokwemvelo iyisignali yayo ye-Quadrature. Ngakho-ke ukuqonda okulula kwezibonakaliso ze-IQ modulation ukucabangela isignali ye-I njengesignali yesithwali se-cosine, kanye nesignali ye-Q njengesignali yesithwali se-sine enomehluko wemvamisa wama-degrees angu-90 kusuka kusignali ye-I.

Okubizwa ngokuthi i-IQ modulation ukusebenzisa isethi yezimpawu ze-I, okungukuthi izimpawu ze-cosine, kanye nezibonakaliso ze-Q, okungukuthi izimpawu ze-sine (ezinomehluko wesigaba sama-degree angu-90 kanye ne-orthogonal komunye nomunye) zemvamisa efanayo nabathwali, ukuze kulungiswe ngesikhathi esisodwa izimpawu ze-baseband ezimbili kubathwali ababili, bese kufakwa izimpawu ezimbili ezilungisiwe ndawonye bese zidluliselwa ngesekethe ye-RF. Ngemva kokuthola isignali yemvamisa yomsakazo, ingxenye yokwamukela isebenza.Ukunciphisa i-IQNgesikhathi sokususwa kwe-IQ, ngoba abathwali ababili bahambisana, izimpawu ezimbili ze-baseband zingahlukaniswa nesignali exubile ngokusekelwe kuzimpawu ze-I ne-Q ezisetshenziswe enkambisweni yokuguqulwa kwangaphambilini futhi zihlukaniswe ngokwehlukana. Kuzo zombili izimpawu ze-I ne-Q eziguqulwe yi-IQ, ukwandisa ubukhulu bohlangothi olulodwa akugcini nje ngokwandisa ubukhulu besignali eguquliwe, kodwa futhi kubangela ukuthi isigaba sesignali eguquliwe sishintshe siye ohlangothini ngokuphakama okukhulu. Ngakho-ke, ukuguqulwa kwe-IQ kuwukuguqulwa kwe-amplitude okwenziwa esignalini ye-I ne-Q, kodwa umphumela wokuguqulwa awuthinti kuphela ubukhulu besignali eguquliwe, kodwa futhi noshintsho lwesigaba saso. Lesi yisimiso esiyisisekelo sokusebenza kokuguqulwa kwe-IQ nokususwa.