Nā Kānana Pass Band Passivehiki ke hana ʻia ma ka hoʻopili ʻana i kahi kānana haʻahaʻa me kahi kānana haʻahaʻa kiʻekiʻe
Hiki ke hoʻohana ʻia ka Passive Band Pass Filter e hoʻokaʻawale a kānana paha i kekahi mau alapine (frequencies) e waiho ana i loko o kahi hui kikoʻī a i ʻole ka laulā o nā alapine (frequencies). Hiki ke hoʻomalu pololei ʻia ke alapine ʻoki a i ʻole ka kiko ƒc i loko o kahi kānana passive RC maʻalahi me ka hoʻohana ʻana i hoʻokahi resistor ma ke ʻano series me kahi capacitor non-polarized, a ma muli o ke ala a puni lākou i hoʻopili ʻia ai, ua ʻike mākou ua loaʻa kahi kānana Low Pass a i ʻole High Pass.
ʻO kahi hoʻohana maʻalahi no kēia ʻano kānana passive i loko o nā noi amplifier leo a i ʻole nā kaapuni e like me nā kānana crossover loudspeaker a i ʻole nā mana leo pre-amplifier. I kekahi manawa pono e hoʻouna wale i kahi laulā o nā alapine i hoʻomaka ʻole ma 0Hz, (DC) a i ʻole e pau ma kekahi kiko alapine kiʻekiʻe akā aia i loko o kahi laulā a i ʻole kahi hui o nā alapine, he haiki a he ākea paha.
Ma ka hoʻohui ʻana a i ʻole "cascading" pū i kahi kaapuni Low Pass Filter hoʻokahi me kahi kaapuni High Pass Filter, hiki iā mākou ke hana i kahi ʻano kānana RC passive ʻē aʻe e hala ana i kahi laulā i koho ʻia a i ʻole "band" o nā alapine i hiki ke haiki a ākea paha me ka hoʻēmi ʻana i nā mea āpau ma waho o kēia laulā. ʻO kēia ʻano hou o ka hoʻonohonoho kānana passive e hana i kahi kānana koho alapine i ʻike pinepine ʻia ʻo Band Pass Filter a i ʻole BPF no ka pōkole.
ʻAʻole e like me ke kānana haʻahaʻa haʻahaʻa e hoʻouna wale ana i nā hōʻailona o kahi alapine haʻahaʻa a i ʻole ke kānana kiʻekiʻe e hoʻouna ana i nā hōʻailona o kahi alapine kiʻekiʻe, hoʻouna nā Band Pass Filters i nā hōʻailona i loko o kahi "band" a i ʻole "spread" o nā alapine me ka ʻole o ka hoʻololi ʻana i ka hōʻailona hoʻokomo a i ʻole ka hoʻokomo ʻana i ka walaʻau keu. Hiki i kēia hui o nā alapine ke lilo i kekahi laulā a ua ʻike nui ʻia ʻo ia ʻo nā kānana Bandwidth.
Ua wehewehe pinepine ʻia ka bandwidth ʻo ia ka laulā alapine (frequency) e kū nei ma waena o ʻelua mau kiko ʻoki alapine (ƒc), ʻo ia hoʻi he 3dB ma lalo o ke kikowaena kiʻekiʻe loa a i ʻole ka piko resonant ʻoiai e hoʻēmi ana a hoʻonāwaliwali paha i nā mea ʻē aʻe ma waho o kēia mau kiko ʻelua.
A laila no nā alapine i hoʻolaha nui ʻia, hiki iā mākou ke wehewehe maʻalahi i ka huaʻōlelo "bandwidth", ʻo BW ʻo ia ka ʻokoʻa ma waena o ke alapine ʻoki haʻahaʻa (ƒcLOWER) a me nā kiko alapine ʻoki kiʻekiʻe (ƒcHIGHER). I nā huaʻōlelo ʻē aʻe, BW = ƒH - ƒL. Maopopo loa no ka hana pono ʻana o kahi kānana pass band, pono ke kiʻekiʻe o ke alapine ʻoki o ke kānana pass haʻahaʻa ma mua o ke alapine ʻoki no ke kānana pass kiʻekiʻe.
Hiki ke hoʻohana ʻia ka Band Pass Filter "kūpono" e hoʻokaʻawale a kānana paha i kekahi mau alapine e waiho ana i loko o kahi hui alapine kikoʻī, no ka laʻana, ka hoʻopau ʻana i ka walaʻau. Ua ʻike nui ʻia nā kānana band pass ma ke ʻano he mau kānana kauoha lua, (ʻelua-pole) no ka mea he ʻāpana reactive "ʻelua", nā capacitors, i loko o kā lākou hoʻolālā kaapuni. Hoʻokahi capacitor ma ke kaapuni haʻahaʻa a me kekahi capacitor ma ke kaapuni kiʻekiʻe.
Hōʻike ka Bode Plot a i ʻole ke alapine pane ma luna i nā ʻano o ka kānana band pass. Maanei ua hoʻēmi ʻia ka hōʻailona ma nā alapine haʻahaʻa me ka hoʻonui ʻana o ka hoʻopuka ma kahi pali o +20dB/Decade (6dB/Octave) a hiki i ka alapine i ka "ʻoki haʻahaʻa" kiko ƒL. Ma kēia alapine, ʻo ke anakahi hoʻopuka he 1/√2 = 70.7% o ka waiwai hōʻailona hoʻokomo a i ʻole -3dB (20*log(VOUT/VIN)) o ka hoʻokomo.
Hoʻomau ka hoʻopuka ma ka loaʻa nui loa a hiki i ka hiki ʻana i ka "ʻoki kiʻekiʻe" ƒH kahi e emi ai ka hoʻopuka ma ka wikiwiki o -20dB/Decade (6dB/Octave) e hoʻēmi ana i nā hōʻailona alapine kiʻekiʻe. ʻO ke kiko o ka loaʻa ʻana o ka hoʻopuka nui loa ʻo ia ka awelika geometric o nā waiwai ʻelua -3dB ma waena o nā wahi ʻoki haʻahaʻa a me luna a ua kapa ʻia ʻo ka waiwai "Centre Frequency" a i ʻole "Resonant Peak" ƒr. Ua helu ʻia kēia waiwai awelika geometric e like me ƒr 2 = ƒ(LUA) x ƒ(LOWER).
Akānana pass bandua manaʻo ʻia he kānana ʻano lua-kauoha (ʻelua-pole) no ka mea he "ʻelua" mau ʻāpana reactive i loko o kona ʻano kaapuni, a laila e pālua ka kihi pae o nā kānana mua i ʻike mua ʻia, ʻo ia hoʻi, 180o. ʻO ke kihi pae o ka hōʻailona hoʻopuka e alakaʻi i ka mea hoʻokomo ma +90o a hiki i ke kikowaena a i ʻole ke alapine resonant, ƒr kiko kahi e lilo ai i "zero" degere (0o) a i ʻole "in-phase" a laila hoʻololi i LAG i ka hoʻokomo ma -90o i ka piʻi ʻana o ke alapine hoʻopuka.
Hiki ke loaʻa nā kiko ʻoki alapine (frequency) o luna a me lalo no kahi kānana pass band me ka hoʻohana ʻana i ke ʻano like me ia no nā kānana pass haʻahaʻa a me ke kiʻekiʻe.
Hele mai nā ʻāpana me nā mea hoʻohui wahine SMA a i ʻole N, a i ʻole 2.92mm, 2.40mm, a me 1.85mm nā mea hoʻohui no nā ʻāpana alapine kiʻekiʻe.
Hiki iā mākou ke hoʻopilikino i ka Band Pass Filter e like me kāu mau koi. Hiki iā ʻoe ke komo i ka ʻaoʻao hoʻopilikino e hāʻawi i nā kikoʻī āu e pono ai.
Ka manawa hoʻouna: Sep-06-2022
