Ngā Āhuatanga o te Pūihi i roto i ngā Pūnaha Whakawhitiwhiti Kōrero
He wāhanga matua ngā pūihi i roto i ngā pūnaha whakawhitiwhiti ahokore. Ko tā rātou mahi he huri i ngā tohu hiko i te tuku hei ngaru hikohiko e horapa ana i te wāhi, kātahi ka mahi i te tukanga whakamuri i te kaiwhiwhi: te hopu i ngā ngaru hikohiko me te huri i aua ngaru hei tohu hiko. Ko te kounga o te hononga whakawhitiwhiti—mai i te whānuitanga me te pono ki te kaha—he nui te awe o ngā āhuatanga o te pūihi e whakamahia ana. Nō reira, he mea nui te mārama ki ngā tawhā pūihi mō ngā kaihoahoa whatunga, ngā tohunga hangarau mara, me ngā ākonga whakawhitiwhiti kōrero.
1. Tauira Irahiko
E whakaahua ana te tauira irahiko i te tukunga o te pūngao hikohiko e te pūihi i ngā ahunga rerekē o te wāhi. Ko te tikanga, ka whakaatuhia tēnei tauira hei kauwhata 2D, 3D rānei, e whakaatu ana i te kaha o te mara, te mana rānei irahikohia hei pānga o te koki. E rua ngā kāwai whānui:
– Ngā pūihi ahunga-katoa, e tuku ana i te hiko kia ōrite te hora i roto i tētahi papa (hei tauira, te papa whakapae). Hei tauira: ngā pūihi monopole/dipole mō ngā pouara Wi-Fi, ngā whakawhitiwhiti reo irirangi rānei.
– Ka arotahi ngā pūihi aronga ki te pūngao i tētahi ahunga motuhake, ka whakanui ake i te whakanui i taua ahunga. Hei tauira, ko ngā pūihi Yagi, parabolic, haona rānei i roto i ngā pūnaha ngaruiti me te amiorangi.
I roto i ngā tauira irahiko, ko ngā kupu matua o te pūwero (e tohu ana i te ahunga o te irahiko mōrahi), taha o te pūwero (e tohu ana i te irahiko tāpiri i waho o te pūwero matua), me muri o te pūwero (e tohu ana i te pūwero o muri). Ka taea e ngā taha teitei te whakararuraru i ētahi atu pūnaha, te whiwhi rānei i te whakararuraru mai i ngā ahunga kāore e hiahiatia.
2. Whiwhinga Pūihi
Ko te whakanui he ine i te kaha o te pūihi ki te arotahi i te kaha i tukuna ki tētahi ahunga e pā ana ki tētahi pūihi tohutoro. He rerekē te whakanui i te kaha i tukuna; kāore e "waihanga" i te mana, engari ka whakatikatika i te tohatoha kaha kia pai ake te ahunga. Ko te whakanui te tikanga e whakaatuhia ana penei:
– dBi: ki te whakataurite ki tētahi pūihi isotropic (he pūihi ariā e horapa ōrite ana ki ngā taha katoa).
– dBd: ki te whakataurite ki te pūihi haurua-ngaru rua.
He pai ngā pūihi whakanui-teitei mō ngā whakawhitiwhiti tawhiti, ngā hononga pūwāhi-ki-pūwāhi rānei. Heoi, he whaiti ake te koki hihi, me tika ake te tāutanga me te whakahāngai.
3. Whānuitanga o te hihi (Whānuitanga o te hihi)
Ko te whānui hihi he ine i te whānui koki o te pūihi matua, e inehia ana i te -3 dB mai i te tihi (Half Power Beamwidth/HPBW). Ko te whānui hihi whaiti he tikanga he tino ahunga te pūihi (he nui te whiwhinga), ko te whānui hihi whānui he tikanga he whānui ake te horahanga engari he iti ake te whiwhinga.
I roto i ngā tono mahi:
– Me whakawhitiwhiti ngā teihana waea pūkoro i waenga i te whānui o te hihi me te kapinga o te rāngai.
– Ko ngā hononga ngaruiti i waenga i ngā whare ka whakamahi i te whānui kurupae whaiti hei whakaiti i te pokanoa me te whakapai ake i te SNR.
4. Te whakapolarisasi
Ko te pōraihana e whakaahua ana i te aronga o te papa hiko (papa-E) o te ngaru e tukuna ana e te pūihi. Ko ngā momo ko:
– Te whakapōreareatanga rārangi: whakapae, poutū rānei.
– Te whakapūtanga porowhita: te whakapūtanga porowhita matau (RHCP) te whakapūtanga porowhita maui rānei (LHCP).
– Te porowhita porowhita: he āhua noa ina kore e taurite ngā wāhanga whakapae me ngā wāhanga poutū.
He mea nui te whakataurite i te pōraihana i waenga i te tuku me te kaiwhiwhi. Mēnā kāore i te ōrite ngā pōraihana, ka ngaro te kore ōritenga o te pōraihana, ka taea ai te whakaiti i te mana e whiwhihia ana. He maha ngā wā ka whakamahia te pōraihana porowhita i roto i ngā whakawhitiwhitinga amiorangi me ētahi āhuatanga maha-ara nā te mea he kaha ake ki ngā huringa aronga.
5. Ārai me te Taurite
He pai te āhua o te aukati tāuru o ngā pūihi ki te aukati o te raina tuku (ko te tikanga he 50 Ω, he 75 Ω rānei). Ka puta ngā whakaata tohu ki te tuku i ngā rerekētanga o te aukati, ā, koinei ngā pānga:
– He whakahekenga mana whai hua kua tukuna.
– Te whakapōturi me te whakamahana o te taputapu tuku.
Ko ngā tawhā whānui mō te aromatawai i te ōritetanga ko:
– VSWR (Ōwehenga Ngaru Tū Ngaohiko): he pai ake te tata atu ki te 1:1.
– Te Ngaronga Whakahoki (dB): ka nui ake te uara (hei tauira, 15 dB, 20 dB) ka pai ake.
Ka taea te whakatutuki i te taurite impedance mā te hoahoa pūihi, te whakamahi i ngā whatunga taurite, te whiriwhiri rānei i ngā taura me ngā hononga e tika ana.
6. Whānuitanga o te Pūihi
Ko te whānui o te ara iahiko e pā ana ki te awhe auau mahi o tētahi pūihi e tutuki tonu ana i ētahi paearu mahi (hei tauira, VSWR < 2, ngaronga whakahoki rānei > 10 dB). Tērā ētahi pūihi whaiti e pai ana mō te awhe auau whaiti anake, ā, kei reira anō hoki ngā pūihi whānui, ngā pūihi tino whānui rānei.
I roto i ngā pūnaha hou pēnei i te LTE, 5G, me te Wi-Fi 6/6E, he mea nui te whānui o te pūihi nā te mea me mahi ngā taputapu i runga i ngā hongere whānui, i ngā hongere maha-roopu rānei. He maha ngā wā ka whakamahia ngā pūihi maha-roopu i roto i ngā waea atamai hei tautoko i ngā ratonga maha i te wā kotahi, ahakoa he uaua ake ā rātou hoahoa nā te iti o te wāhi.
7. Te Whai Hua o te Pūihi
Ko te whai huatanga e whakaahua ana i te nui o te mana hiko e uru ana ki te pūihi ka hurihia hei irahiko hikohiko. Ka puta mai ngā mate i:
– Te ātete o te arataki hiko (te ngaronga ohmic),
– Te ngaronga hiko-kore i runga i te papa (mō ngā pūihi moroiti),
– Te ngaronga i runga i te whatunga taurite,
– Te hononga ki ngā wāhanga e karapoti ana (hei tauira, te anga, te pākahiko, te papa whenua iti).
Ko te iti o te whai huatanga he nui te mana ka "ngaro" ki te wera, ka whakaiti i te whānuitanga. I roto i ngā taputapu iti pēnei i ngā pūnga IoT me ngā waea pūkoro, he wero nui te whai huatanga nā te mea he iti ake te rahi o te pūihi i te roanga ngaru pai.
8. Te Ārahitanga me tōna Hononga ki te Whiwhinga
Ko te aronga he mehua o te "aronga" o te pūihi, i runga i tōna tauira irahiko me te kore e whakauru i ngā mate o roto. Ko te whiwhinga ko te aronga i whakareatia ki te whai huatanga. I roto i te ariā:
Whiwhinga = Te Arotahi × Te Whai Hua
Nō reira, tera pea he teitei te aronga o te pūihi engari kāore i te tino teitei te pikinga e ai ki te mea e tumanakohia ana mēnā he nui ngā mate. I roto i te hoahoa pūnaha, he mea nui ngā mea e rua: te aronga ki te arotahi i te kapinga, me te whai huatanga hei whakarite kia kore e moumou te mana.
9. Ōwehenga o Mua-ki-Mua (F/B)
Ko te Ōwehenga o Mua-ki-Muri e tohu ana i te ōwehenga o te mana tuku i mua (te pū matua) ki muri. He mea hiahia kia teitei te uara F/B mō te pūihi ahunga kia iti ai te whiwhinga/whiwhinga o muri. He mea nui tēnei tawhā mō:
– Pūihi Yagi mō te pouaka whakaata, reo irirangi rānei,
– Hononga pūwāhi-ki-pūwāhi hei whakaiti i te pokanoa mai i muri,
– Ngā pūnaha me ngā tuku maha i te wāhi kotahi (te tiritiri pae).
10. Ngā Take Taiao me te Tāutanga
Ko ngā āhuatanga o te pūihi e whakatauhia ana ehara i te mea ko te hoahoa anake engari ko te taiao tāutanga anō hoki. Ko te teitei o te pūihi, te tata ki te konganuku, te whakatakotoranga, te roa o te taura, te kounga o te hononga, me ngā arai ā-tinana (ngā whare, ngā rākau) ka taea te whakarerekē i te tauira irahiko me te whakaheke i te mahi. Ka taea e ngā āhuatanga maha-ara (whakaata) te whakapakari, te whakaiti rānei i te tohu i tētahi wāhi motuhake. Nō reira, he maha ngā wā ka mahia ngā whakamātautau mara pēnei i ngā inenga RSSI me te SNR me ngā whakamātautau taraiwa hei whakarite kia rite te mahi a te pūihi ki tā te mea e tumanakohia ana.
Whakamutunga
Ehara ngā pūihi i te "kaituku tohu" noa iho, engari he taputapu hikohiko me ngā āhuatanga hangarau maha: te tauira irahiko, te whakanui, te whānui o te hihi, te whakapūmau, te aukati me te taurite, te whānui o te whiti, te whai huatanga, te aronga, me te ōwehenga o mua-ki-muri. Ka whakatauhia e ēnei tawhā te whānuitanga, te kounga tohu, te ātete ki te pokanoa, me te pono o tētahi pūnaha whakawhitiwhiti kōrero. I roto i te mahi, me whai whakaaro te kōwhiringa pūihi ki ngā whakaritenga tono (te tawhiti, te auau, te nekenekehanga, me te taiao), me te whakarite kia tika te tāutanga hei whakatutuki i te mahi kua hoahoatia.
