Helu kuʻina o nā leo 'ike

Kekahi kaʻina hana hiki nae ke hoohuliia i loko o kikoho palapala. Penei, hoʻopā'ālua o nā leo 'ike Via kamepiula' ē aʻe ua lawe mai ia penei:

- ea kuekueni hoʻopaʻa ikepili koʻikoʻi manaʻo;

- i huli ana i loko o ka uila pono, ai ka alapine (ikaika hawewe) loli aʻe pela;

- ka kūpono he ua Eia kekahi laʻana, a laila loaʻa o kona mea hōʻikeʻikeʻuʻuku (i kekahi manawa aku nei au i hoʻopaʻa aeaie hoʻopā'ālua nā leo 'ike).

Ke kūpono Analog lolouila mua nā leo pele i ka maikaʻi, ka mea kiekie ka alapine (frequency) o nā Eia kekahi laʻana i ka mea hōʻikeʻikeʻuʻuku a me ka helu kuʻina ka hohonu.

Ma na olelo e ae, hoʻopā'ālua o na nā leo 'ike - mea he ninau kaʻina hana o ka hoʻololi' ana i na mea he nui Analog peahi ana i loko o ka kikoho, manao no hou aaioee i ka mea kūpono. E i nāʻanuʻu a me kāu kiʻina hana o digitizing kani mai noʻonoʻo.

Discretization o ka manawa maoli - o ke kumu no ka digitizing. E like me ka Kotel'nikova theorem, ka mea like uila neaiae hiki ke digitized e heluhelu i kekahi mua o kekahi ana moʻo o aiee o kona ikaika hawewe. Ke alapine (frequency) o ia kāuʻikepili e e oi palua ma ka liʻiliʻi loa i ke kali alapine (frequency) o ka papa kuhikuhiE neaiaea. Inā pono, digitizing mea like "kumu kivila" i ka pae'ōnaehana alapine (frequency) o 0-20 kHz mea hōʻikeʻikeʻuʻuku e halihaliia oia iwaho ole e emi malalo o 40 tausani. Times no kekona (40 kHz). Mea hōʻikeʻikeʻuʻuku pili i ka helu o nā ana no kekona Analog neaiae kumu (mea hōʻikeʻikeʻuʻuku, i ka mea hōʻikeʻikeʻuʻuku alapine (frequency)). Me ka hoʻoulu hāpana, piʻi pū,ʻaʻole wale nō ka mea e like ai akā, i ka buke o ke kūponoʻikepili kahawai.

Nō hoʻi, 'ike helu kuʻina nā leo e, e hanaʻia i loko o nāʻaoʻao. Like, no ka laʻana, ma ka digitizing ka nonuniform quantizer, i kekahi manawa kapa pālākiō. I ka hoʻohana 'ana i ka holoʻokoʻa ikaika hawewe huahelu conditionally puunaueia i na pauku me ka kiʻekiʻe a me ka haahaa nā loina. E möakäka hou hoʻopā'ālua nā leo 'ike ia lŘlŘ ma ana nui dala o ka quantization pae ma wahi me ka uuku ikaika hawewe waiwai (a me ka Hope versa). 'Ōlelo Aʻo, nae, i ka huina helu o nā pae koe ka ia me ia ma kaʻaʻahu quantization iaoia (PCM).

An okoa hoʻokokoke ua hoʻokō i loko o kekahi koho hoʻopā'ālua hana. Ua Ua kapaia "palena pau pāpaʻa Code Modulation» (DPCM). Me ia i kekahi papa hana ua hookauwa ole oia ia ia quantization o ka ikaika hawewe o ka pololei neaiaea a me kona hoahanau waiwai. E like me ka hopena hiki e loaʻa ai ka ho'ēmiʻana o ka buke noho ma ka 'ikepili, mai keʻano papa hana ua hoʻohana mahope i ka olelo wanana o ka palapala neaiaea Eia kekahi laʻana.

Ka helu kuʻina a me ka aaioee nā leo 'ike i ho'ākāka' ia i loko o keia pepa pono hana huli ana "Analog-i-kikohoʻe". Kēia kaʻina ua hana ka hoʻohana 'ana i ka ADC (Analog-i-kikohoʻe mīkini hoʻololi). Me keia hana, kēlā mea maka i kela la kamepiula mea nāna i hoʻolako pono me ka leo kāleka (i loko o keia hihia he mea kekahi nana e hoole kaʻina - e loaa ana i ka Analog neaiaea, mai ka mīkini kahawai).

ADC oihana e like penei:

- i kaupalena 'alapine (frequency) bandwidth. E ho ohana i kānana, e hōʻokiʻia ka hōʻailona eiiiiiaiou, i ke alapine (frequency) o a - oi ma mua o ka hapalua o ka mea hōʻikeʻikeʻuʻuku alapine (ke kumu i hoakakaia mamua).

- Anahonua, o ka ikaika hawewe loina ma mauʻanuʻu. Ke kūpono Analog neaiae ua poe ma ke kaʻina o hookahi'āpana o ka loli iki pinepine '(discretization).

- hope mea loaa'āpana lākou hoʻopuniʻana aiee, mai ka paʻa 'ia paha (quantization).

- hoohuli kēlā quantized waiwai o ka conditional helu o ka quantization pae (kēlā me kēia waiwai - kona pūkaʻina helu). 'O kēia ka hope kahua o ka digitization.