Imodyuli yesigaba yisekethe apho isigaba se-carrier wave silawulwa ngumqondiso wokumodareyitha. Kukho iintlobo ezimbini ze-sine wave phase modulation: ukumodareyitha kwesigaba esithe ngqo kunye nokumodareyitha kwesigaba esingathanga ngqo. Umgaqo-siseko wokumodareyitha kwesigaba esithe ngqo kukusebenzisa umqondiso wokumodareyitha ukuguqula ngokuthe ngqo iiparitha ze-loop ye-resonant, ukwenzela ukuba umqondiso we-carrier nge-resonant loop ukuvelisa ukutshintshwa kwesigaba kunye nokwenza i-modulation wave wave; Indlela yokumodareyitha yesigaba esingathanga ngqo kuqala imodareyitha i-amplitude ye-modulated wave, kwaye emva koko iguqule utshintsho lwe-amplitude kwinguqu yesigaba, ukuze kuphunyezwe ukumodareyitha kwesigaba. Le ndlela yenziwa ngu-Armstrong ngo-1933, ebizwa ngokuba yi-Armstrong modulation method
I-electronic controlled microwave phase shifter yi-network ye-port-port esetyenziselwa ukubonelela umahluko wesigaba phakathi kwemveliso kunye neempawu zegalelo ezinokulawulwa ngumqondiso wokulawula (ngokubanzi i-DC bias voltage). Isixa sokutshintsha kwesigaba sinokuhluka ngokuqhubekayo kunye nomqondiso wokulawula okanye kwixabiso eliqingqiweyo elinqunywe kwangaphambili. Zibizwa ngokuba zii-analog phase shifters kunye ne-digital phase shifters ngokulandelelanayo. Imodyuli yesigaba yimodyuli yesigaba sokubini sokutshintsha isitshixo semodyuli kwinkqubo yonxibelelwano lwemicrowave, esebenzisa amaza asisikwere esiqhubekayo ukumodareyitha umqondiso womthwali. I-Sine wave phase modulation inokwahlulwa ibe yimodyuli yesigaba esithe ngqo kunye nokumodareyitha kwesigaba esingathanga ngqo. Ngokusebenzisa unxulumano lokuba i-sine wave amplitude i-Angle iyinxalenye ye-frequency frequency, i-frequency modulated wave inokuguqulwa ibe yi-modulated wave wave (okanye ngokuchaseneyo). Eyona isetyenziswa ngokuqhelekileyo isekethe yemodyuli yesigaba esithe ngqo yi-varactor diode phase modulator. I-indirect phase modulation circuit inzima kakhulu kunesekhethi yemodulation yesigaba esithe ngqo. Umgaqo wayo kukuba enye indlela yesignali ye-carrier iguqulwa yi-90 ° yesigaba se-shifter kwaye ingene kwi-balanced amplitude-modulator ukucinezela i-amplitude modulation yomthwali. Emva kokunciphisa okufanelekileyo, umqondiso ofunyenweyo wongezwa kwenye indlela yomphathiswa ukuze ukhuphe umqondiso we-amplitude-modulating. Le ngqungquthela ibonakaliswe ngokuzinza okuphezulu, kodwa ukutshintshwa kwesigaba akunakuba kukhulu kakhulu (ngokuqhelekileyo ngaphantsi kwe-15 °) okanye ukuphazamiseka okukhulu. Imodyuli yesigaba esilula ihlala isetyenziswa kwii-FM zosasazo.
