Q wa dera ndi kulandira wailesi

Pa wailesi aliyense kumadalira pa mfundo za kusankha chizindikiro kubalana modulated ndi zina chonyamulira pafupipafupi, womwe anatsimikiza ndi kumveka kwa dera zokhala ndilo mbali yaikulu ya dera wolandirayo. Mmene kukonza pafupipafupi ichi, zimadalira mtundu wa chizindikiro analandira adzakhala anasankha.

Selectivity, kapena wolandila selectivity Mungasankhe ndi chizindikiro n'kusokoneza phwando zisathe adzakhala attenuated, pamene zothandiza - ndi kumakula. Q a dera la - ndi kuchuluka moyenera anasonyeza mwa mawu n'zosangalatsa kumva bwino kwa ntchito imeneyi.

Pafupipafupi resonant a dera la anatsimikiza ndi Thompson chilinganizo:

f = 1 / (2π√LC), mmene

L - ndi inductance;

C - kufunika capacitance.

Kuti timvetse mmene oscillations zimachitika dera, muyenera kudziwa momwe ntchito.

Ndipo capacitive, ndi akatundu inductive kuteteza zosayembekezereka wa magetsi, koma mu zosiyana. Choncho, iwo kulenga zinthu kuonekera kwa ndondomeko oscillation, pafupi zofanana monga amachita pa pachimake pamene Otsetsereka awiri kukankha iwo mu madera osiyana alternately. Theoretically, kusintha mtengo wa capacitor kapena koyilo, munthu akhoza kukwaniritsa kuti pafupipafupi resonant wa kuzungulira lifanane ndi chonyamulira pafupipafupi wailesi kupatsira. Yaitali osiyana, chindichepere adzakhala khalidwe chizindikiro. Zochita wolandirayo ndi anatsekula ndi kusintha capacitance wa capacitor lapansi.

Funso lonse, kodi lakuthwa adzakhala pachimake pa Zithunzi za pafupipafupi zimene wolandila lapansi. Momwemo mukhoza zowoneka kumvetsa chizindikiro zothandiza mmene kuwasokonezera kuletsedwa chidzakula. Ndipo Q wa dera ndi chizindikiro chimene ndiyo selectivity wa phwando.

Iwo limanenedwa mfundo:

Q = 2πFW / P, kumene

F - ndi resonant pafupipafupi dera la;

W - mphamvu mu dera resonant;

P - mphamvu madyaidya ndikuledzera.

Q a dera zogwiritsidwa mu kufanana ndi inductance wa capacitor ndi anatsimikiza ndi chilinganizo zotsatirazi:

Q = R√ (C / L)

Kuyambira khalidwe inductance ndi capacitance bwino, ndipo R, iwo anakumbukira kuti pambali pa reactance koyilo ndi chigawo resistive. Choncho, dera nthawi zambiri zimasonyeza dera kuphatikizapo m'menemo atatu zinthu izi: capacitance C, inductance L ndi kukana R.

Q wa dera ndi mtengo inversely njila kwa mlingo wa kuvunda oscillation m'menemo. Ikuluikulu ilo liriri, pang'onopang'ono ndi zosangalatsa za kachitidwe.

Zochita chinthu chofunika kwambiri okhudza Q wa dera ndi khalidwe la koyilo, amene zimadalira pa permeability wa pakati pake penipeni, chiwerengero cha motsatana, mlingo wa waya kudzipatula ndi pa kukana ake, ndiponso kwa zomvetsa pa ndime ya mafunde mkulu-pafupipafupi. Choncho, kusintha pafupipafupi makonzedwe kawirikawiri ntchito capacitors variable, amene ali miyeso iwiri yopyapyala kukhala mwa wina ndi mnzake pamene kasinthasintha. Chotero dongosolo ndi zina pafupifupi onse mawailesi sanali yadigito.

Komabe, mu wolandila ndi digito ikukonzekera amakhazikitsa madera omwe resonant, chabe ndi kusintha awo resonant pafupipafupi mosiyana.