Izihlungi ze-Passive Band Pass
Izihlungi ze-Passive Band Passkungenziwa ngokuxhumanisa isihlungi sokudlulisa esiphansi nesihlungi sokudlulisa esiphezulu
Isihlungi se-Passive Band Pass singasetshenziswa ukuhlukanisa noma ukuhlunga amaza athile angaphakathi kwebhendi ethile noma ububanzi bamaza. Imvamisa yokusika noma iphuzu le-ƒc kusihlungi esilula se-RC passive ingalawulwa ngokunembile kusetshenziswa i-resistor eyodwa kuphela ngokulandelana ene-capacitor engavulwanga, futhi kuye ngokuthi ixhunywe ngayiphi indlela, sibonile ukuthi kutholakala isihlungi se-Low Pass noma se-High Pass.
Ukusetshenziswa okulula kwalezi zinhlobo zezihlungi ezingasebenzi kusezinhlelweni zokusebenza ze-audio amplifier noma kumasekethe afana nezihlungi ze-loudspeaker crossover noma izilawuli zethoni zangaphambi kwe-amplifier. Ngezinye izikhathi kuyadingeka ukudlula kuphela ububanzi obuthile bemvamisa engaqali ku-0Hz, (DC) noma ephela endaweni ethile ephezulu yemvamisa kodwa engaphakathi kwebanga elithile noma ibhendi yamaza, kungaba mancane noma abanzi.
Ngokuxhumanisa noma "ukuhlanganisa" ndawonye isekethe eyodwa ye-Low Pass Filter nesekethe ye-High Pass Filter, singakhiqiza olunye uhlobo lwe-passive RC filter oludlula ububanzi obukhethiwe noma "ibhendi" yamaza angaba mancane noma abanzi ngenkathi kunciphisa bonke labo abangaphandle kwalolu bubanzi. Lolu hlobo olusha lwelungiselelo le-passive filter lukhiqiza isihlungi esikhetha amaza esaziwa ngokuthi i-Band Pass Filter noma i-BPF ngamafuphi.
Ngokungafani nesihlungi se-low pass esidlulisa kuphela amasignali ebanga lemvamisa ephansi noma isihlungi se-high pass esidlulisa amasignali ebanga lemvamisa ephezulu, izihlungi ze-Band Pass zidlulisa amasignali ngaphakathi "kwebhendi" ethile noma "ukusabalala" kwamafrikhwensi ngaphandle kokuphazamisa isignali yokufaka noma ukwethula umsindo owengeziwe. Leli bhendi lamafrikhwensi lingaba yinoma yiluphi ububanzi futhi laziwa kakhulu ngokuthi izihlungi i-Bandwidth.
I-bandwidth ivame ukuchazwa njengobubanzi bemvamisa obukhona phakathi kwamaphuzu amabili acacisiwe okusika imvamisa (ƒc), angama-3dB ngaphansi kwesikhungo esiphezulu noma i-resonant peak ngenkathi kunciphisa noma kubuthakathaka amanye angaphandle kwala maphuzu amabili.
Bese kuthi kuma-frequency asakazeke kabanzi, singachaza igama elithi “bandwidth”, i-BW njengomehluko phakathi kwama-curve aphansi (ƒcLOWER) kanye nama-curve aphezulu (ƒcHIGHER). Ngamanye amazwi, i-BW = ƒH – ƒL. Ngokusobala ukuze isihlungi sebhendi yokudlula sisebenze kahle, i-curve yokuvala yesihlungi sokudlula esiphansi kumele ibe phezulu kune-curve yokuvala yesihlungi sokudlula esiphezulu.
Isihlungi se-Band Pass “esifanele” singasetshenziswa futhi ukuhlukanisa noma ukuhlunga amaza athile angaphakathi kwebhendi ethile yamaza, isibonelo, ukukhanselwa komsindo. Amaza okudlulisa amabhendi aziwa ngokuvamile ngokuthi amaza okulandelana kwesibili, (ama-pole amabili) ngoba anengxenye “embili” esabelayo, ama-capacitor, ngaphakathi komklamo wawo wesekethe. I-capacitor eyodwa esesekethe esiphansi kanye nenye i-capacitor esesekethe esiphakeme.
I-Bode Plot noma ijika lokuphendula imvamisa elingenhla libonisa izici zesihlungi se-band pass. Lapha isignali iyancishiswa kuma-frequency aphansi lapho umphumela ukhuphuka khona emthambekeni ongu-+20dB/Decade (6dB/Octave) kuze kube yilapho imvamisa ifinyelela iphuzu "eliphansi lokusika" ƒL. Kuleli mvamisa i-voltage yokukhipha iphinde ibe ngu-1/√2 = 70.7% yenani lesignali yokufaka noma -3dB (20*log(VOUT/VIN)) yokufakwayo.
Umphumela uyaqhubeka ekuzuzeni okuphezulu kuze kube yilapho ufinyelela iphuzu "eliphezulu lokusika" ƒH lapho umphumela wehla ngesilinganiso esingu--20dB/Decade (6dB/Octave) okunciphisa noma yiziphi izimpawu zemvamisa ephezulu. Iphuzu lokuzuza komphumela ophezulu ngokuvamile liyisilinganiso sejiyometri senani le--3dB eliphakathi kwamaphuzu aphansi naphezulu okusika futhi libizwa ngokuthi "i-Centre Frequency" noma inani le-"Resonant Peak" ƒr. Leli nani eliphakathi lejiyometri libalwa njenge-ƒr 2 = ƒ(PHEZULU) x ƒ(PHANSI).
Aisihlungi se-band passibhekwa njengesihlungi sohlobo lwesibili (ama-pole amabili) ngoba inezingxenye "ezimbili" ezisebenzayo ngaphakathi kwesakhiwo sayo sesekethe, khona-ke i-engeli yesigaba izoba kabili kunezihlungi ze-engeli yokuqala ezibonwe ngaphambilini, okungukuthi, 180o. I-engeli yesigaba sesignali yokukhipha ihola lokho kokufaka ngo-+90o kuze kufike emvamisa ephakathi noma ephindaphindayo, iphuzu elingu-ƒr lapho iba amadigri "zero" (0o) noma "esigabeni" bese ishintshela ku-LAG kokufaka ngo--90o njengoba imvamisa yokukhipha ikhuphuka.
Amaphoyinti okunqamula aphezulu naphansi esihlungi se-band pass angatholakala kusetshenziswa ifomula efanayo naleyo yezihlungi ze-low pass kanye ne-high pass, Isibonelo.
Amayunithi eza nezixhumi ezijwayelekile ze-SMA noma ze-N zesifazane, noma izixhumi ezingu-2.92mm, 2.40mm, kanye ne-1.85mm zezingxenye zemvamisa ephezulu.
Singakwazi futhi ukwenza ngokwezifiso i-Band Pass Filter ngokwezidingo zakho. Ungangena ekhasini lokwenza ngokwezifiso ukuze unikeze imininingwane oyidingayo.
Isikhathi sokuthunyelwe: Septhemba-06-2022
