Unxibelelwano lwedijithali olungenazingcingo: Umgaqo osebenzayo wokumodareyitha kwe-IQ

Unxibelelwano lwedijithali olungenazingcingo: Umgaqo osebenzayo weUkumodareyitha kwe-IQ
Ukumodareyitha kwe-IQ kusisiseko seendlela ezahlukeneyo zokumodareyitha komgangatho ophezulu osetyenziswa ngokubanzi kwiinkalo ze-LTE kunye ne-WiFi, ezifana ne-BPSK, QPSK, QAM16, QAM64, QAM256, njl. Ukuqonda umgaqo-nkqubo wokumodareyitha kwe-IQ kubalulekile ekuqondeni ngcono indlela yokuphunyezwa kwe-OFDM ephantsi kwi-LTE kunye ne-WiFi. Ngenxa yokuba iindlela zokumodareyitha ezisetyenzisiweyo kwi-subcarrier nganye ye-OFDM ziseziindlela ezahlukeneyo zokumodareyitha ze-QAM ezisekwe kwimodulation ye-IQ, kwaye ngokusisiseko, ukuphunyezwa kwe-OFDM kukugqwesa kwe-IQ yokumodareyitha kwii-subcarriers ezininzi ze-orthogonal.
Iikhonsepthi zika-I no-Q kumodyuli we-IQ zihambelana nezishunqulelo zamagama amabini esiNgesi: KwiSigaba kunye neQuadrature, ngokulandelelanayo. Ukuthetha nje ngokusuka kwintsingiselo yokoqobo, amagama eempawu ze-I kunye ne-Q azinantsingiselo. Yintoni kwisigaba? Yintoni i-orthogonality? Ngowuphi umqondiso osetyenziswayo njengesalathiso sokumisela kwi-isigabakunye nequadrature? Ekuphunyezweni okusebenzayo, iseti ye-cosine kunye namaza e-sine exesha elifanayo asetyenziswa ngokubanzi njengeempawu ze-I kunye ne-Q. Ke ngoko, umqondiso we-cosine osetyenziswa njengophawu lwe-I ngenene luphawu lwereferensi, oluluphawu lweSigaba. Umqondiso we-cosine ongama-90 degrees ngaphandle kwesigaba kunye nomqondiso we-I ngokwemvelo ngumqondiso we-Quadrature. Ngoko ke ukuqonda okulula kweempawu zokumodareyitha kwe-IQ kukuqwalasela i-signal ye-I njengophawu lomthwali we-cosine, kunye nomqondiso we-Q njengophawu lomthwali we-sine kunye nokwahlukana okuphindaphindiweyo kweedigri ze-90 ukusuka kwi-signal ye-I.

Oko kubizwa ngokuba yi-IQ modulation kukusebenzisa imiqondiso ye-I, eyile imiqondiso ye-cosine, kunye nemiqondiso ye-Q, eyile imiqondiso yesine (enomohluko wesigaba samadigri angama-90 kunye ne-orthogonal enye kwenye) yefrikhwensi efanayo nabathwali, ngaxeshanye ukumodareyitha imiqondiso emibini ye-baseband kubathwali ababini, kwaye emva koko ugqithise imiqondiso emibini kunye nokuguqulelwa kwe-RF ngesekhethi. Emva kokufumana isignali yefrikhwensi yerediyo, isiphelo sokufumana siyasebenzaUkunciphisa i-IQ. Ngethuba lokuchithwa kwe-IQ, ngenxa yokuba abathwali ababini be-orthogonal omnye komnye, izibonakaliso ezimbini ze-baseband zingahlukaniswa kwi-signal edibeneyo esekelwe kwi-I kunye ne-Q ye-carrier ye-carrier esetyenziswe kwinkqubo yangaphambili yokumodareyitha kwaye idilizwe ngokwahlukileyo. Kuzo zombini imiqondiso ye-I kunye ne-Q emodareyithwe yi-IQ, ukonyusa i-amplitude ehambelanayo yecala elinye akunyusi nje i-amplitude yesiginali emodareyithiweyo, kodwa ikwabangela ukuba isigaba sophawu olumodareyithwe sitshintshele kwicala elinokwanda kwe-amplitude. Ke ngokusisiseko, ukumodareyitha kwe-IQ kukumodareyitha kwe-amplitude okwenziwa kwisiginali ye-I kunye nophawu lwe-Q, kodwa isiphumo sokumodareyitha asichaphazeli nje kuphela i-amplitude yesiginali emodareyithiweyo, kodwa kunye nokutshintsha kwesigaba sayo. Lo ngumgaqo osisiseko wokusebenza kwe-IQ yokumodareyitha kunye nokunciphisa.