te whakapūtanga SARe whakaahua ana i te whakatakotoranga o te mara hikohiko e tukuna ana, e whiwhihia ana hoki e te pūnaha radar whakatuwheratanga hangai. Nā te mea he rerekē te horapa o ngā mara whakapae me ngā mara poutū o ngā mata me ngā hanganga rerekē, ko te pōraihana tētahi o ngā taurangi tino whai hua mō te whakamārama i ngā whakaahua SAR.
E whakamārama ana tēnei aratohu i ngā hongere whakapūtanga raina e whā - HH, HV, VH me VV - me ngā momo hopu e toru e whakamahia whānuitia ana: te whakapūtanga kotahi, te whakapūtanga takirua me te whakapūtanga katoa (tapawhā). E whakamārama ana hoki i te huarahi e whiriwhiri ai ngā kaihangarau i tētahi aratau mō te pūoko mamao, te whakamātautau radar me te aromatawai pūnaha pūihi.
He aha te Whakapolarisasi SAR?
Ko te nuinga o ngā pūnaha SAR e whakamahia ana e te mokowā he whakapōreareatanga rārangi whakapae (H) me te poutū (V). Mā te waehere hongere reta-rua ka tautuhia te whakapōreareatanga kua tukuna i te tuatahi, ā, ko te whakapōreareatanga kua whiwhihia i muri mai. Hei tauira, ko te tikanga o te HH he tuku whakapae me te whiwhinga whakapae, ko te tikanga o te HV he tuku whakapae me te whiwhinga poutū.
He mea nui te whakapūtātanga nā te mea ka taea e te ūnga te pupuri i te whakapūtātanga taupatupatu, te huri, te tango rānei i te pūtātanga o te hokinga mai. Ko te taratara o te mata, te āhuahanga, ngā āhuatanga dielectric, te roangaru, te koki taupatupatu me te hanganga o roto ka pā ki te hokinga whakamuri kua inehia. Nō reira, me whakamārama te whakapūtātanga me te roopu auau, te āhuahanga tirohanga me ngā raraunga whakaahua kua whakatikatikaina.
He aha te tikanga o HH, HV, VH me VV?
| Hongere | Tuku | Whiwhi | Whakarōpūtanga |
|---|---|---|---|
| HH | Whakapae | Whakapae | Ngātahi-polarized |
| HV | Whakapae | Poutū | Whakawhiti-polarized |
| VH | Poutū | Whakapae | Whakawhiti-polarized |
| VV | Poutū | Poutū | Ngātahi-polarized |
He hongere kō-polarized a HH me VV nā te mea he ōrite ngā polarization tuku me ngā polarization whiwhi. He hongere whakawhiti-polarized a HV me VH nā te mea he orthogonal te polarization whiwhi ki te polarization tuku. I roto i tētahi pūnaha monostatic tauutuutu kua whakatikatikaina, he rite tonu ngā urupare a HV me VH, engari ka puritia ngā hongere e rua i roto i ngā inenga polarization katoa.
Ngā Aratau Matua e Toru mō te Whakapūtanga SAR
1. Te Whakapūtanga Kotahi
Ka hopukina e te hopunga kotahi-polarization tētahi hongere, ko te nuinga ko te HH, ko te VV rānei. Ka iti ake te rahinga raraunga, ka māmā ake te tukatuka ina he rawaka tētahi hongere kua whakamanahia. Ko te herenga ko te iti ake o ngā mōhiohio e tukuna ana e tētahi hongere mō ngā tikanga marara me te hanganga ūnga.
2. Te Whakapōraru Takirua
E rua ngā hongere e hopukina ana e te hopunga polarization-rua. Ko ngā huinga noa ko te HH+HV me te VV+VH, ka tukuna e te radar tētahi polarization, ā, ka whiwhi i ngā hokinga polarization-tahi me ngā hokinga polarization-whiti. Ka tautokohia hoki e ētahi pūnaha he takirua polarization-tahi pērā i te HH+VV. Ka tāpirihia e ngā raraunga polarization-rua he wehewehenga whai hua, me te pupuri i te tere raraunga me ngā whakaritenga tukatuka kia ngāwari ake te whakahaere i te polarization katoa. E kī ana te ESA e tautoko ana a Sentinel-1 i te VV+VH, i te HH+HV rānei i roto i āna kaupapa polarization-rua.
3. Te Whakapōratanga Katoa, te Whakapōratanga Tapawhā rānei
Ka tuhia e te SAR polarimetric katoa a HH, HV, VH me VV hei hongere matatini. Ka tukuna e te radar quad-pol matarohia a H me V i roto i te raupapatanga, ā, ka whiwhi hoki i ngā hokinga mai o H me V, me te pupuri i ngā mōhiohio whānui me te āhua ā-whānau. Ka tautokohia e tēnei te tātaritanga marara-matrix me te wehewehenga taipitopito o te ūnga, te whakarōpūtanga me te whakaahuatanga.
Ko te taupatupatu he nui ake te uaua o te pūnaha, te tono whakatikatika, te rahinga raraunga me te kaha tukatuka. I runga i te pūoko, ka uru pea te mahi pol-katoa ki tētahi ara whaiti ake, ki ētahi herenga hopu rerekē rānei. Ko te polization kiato tētahi atu hoahoa SAR whai mana, engari he rerekē i ngā aratau raina kotahi-, takirua- me te pol-whā tuku iho e kōrerohia ana i konei.
Te Whakapūtātanga-Kotahi me te Whakapūtātanga-Whakawhiti
He maha ngā wā ka tiakina e ngā hongere kō-polarized ngā hokinga kaha mai i ngā mata me ngā hanganga e pupuri ana i te polarization kua tukuna. Ko ngā hokinga whakawhiti-polarized e tohu ana i whakarerekē te tukanga marara i tētahi wāhanga o te āhua polarization mā te marara rōrahi, ngā whakaata maha, te āhua matatini, te hanganga anisotropic rānei.
- Wai marino me ngā mata maeneene:he maha ngā wā ka pōuri te āhua ina whakaatahia te nuinga o te pūngao ki tua atu i te radar; ka taea e te taratara, te hau me te koki taunga te whakanui ake i te marara whakamuri.
- Te tipu:Ka hangaia e ngā manga, ngā take me ngā rau te marara o te rōrahi, nō reira ka taea e ngā hongere whakawhiti-poro te tāpiri i ngā mōhiotanga hanganga whai hua.
- Ngā tāone nui:Ka taea e ngā whare me ngā mata whenua te whakaputa i ngā hokinga kaha o te co-pol me te marara rua-pekepeke, i runga i te whakatakotoranga me te āhuahanga whakaahua.
- Oneone, hukarere me te hukapapa:Ka pāngia te urupare pōraritanga e te makuku, te taratara, te hohonu, te roanga ngaru me te hanganga o roto.
He mātāpono whakamārama ēnei, ehara i te ture whānui. Kaua te hongere e tīpakohia i runga i te whānuitanga o te radar, te koki pānga, te taumira, te wā me te kounga o te whakatikatika.
Me pēhea te whiriwhiri i tētahi Aratau Whakapolarization SAR
| Whakaritenga | Te tīmatanga whai hua |
|---|---|
| Te aroturuki i te rohe whānui, te iti rānei o te rahinga raraunga | Kotahi-pōti ina tutuki te whāinga kimi i tētahi hongere whai mana |
| Te whakahāwea i te tipu, te ahuwhenua, te uhi whenua rānei | Ngā raraunga takirua-polarized me te whakawhiti-polarized mō ngā mōhiohio marara tāpiri |
| Mahere hukapapa moana, moana, waipuke rānei | Kōwhiria ngā aratau e hangai ana ki te HH, ki te VV rānei, e ai ki te roopu, te koki taunga me te tikanga kua whakamanahia. |
| Te whakarōpūtanga matatau, te wetewete marara rānei | Ko te quad-pol katoa ina hiahiatia he mōhiohio e whā-awa kua whakatikatikaina i te wāhanga |
Ko te aratau pai rawa atu he mea motuhake ki te tono. Me whakarite e ngā kaihangarau ngā ihirangi mōhiohio ki te kapinga, te taumira, te ōwehenga tohu-ki-haruru, te whānuitanga, te wā tirotiro anō, ngā rauemi tukatuka me te āheinga whakatikatika.
Ngā Whakaaro mō te Pūihi me te RF mō te Radar Polarimetric
Ehara i te mea ko te pūnaha tukatuka anake te mea e whakawhirinaki ana ki ngā inenga polarimetric pono. Me mau tonu te mahi pumau o te pūihi me te mekameka RF i ngā hongere polariization e rua. Ko ngā tawhā nui ko:
- te auau whakahaere me te whānui o te whānui inamata;
- te taurite o te pikinga me te taurite o te tauira-ira i waenga i ngā tauranga H me V;
- te wehewehe tauranga-ki-tauranga me te wehewehe whakawhiti-poka;
- te pumau o te kaha me te āhua;
- VSWR, atanga hononga me te whakatikatika taura;
- te whakaritenga o te pūihi, te āhua o te whakairinga me te papa tohutoro whakatikatika.
Ngā taonga RF MISOngā pūihi haona takirua-polarized, ngā pūihi haona takirua-polarized whānuime ētahi atu otinga pūihi RF mō ngā mahi radar, ine me te whakauru pūnaha. Me whiriwhiri tonu te tauira i runga i te pepa raraunga o nāianei me ngā whakaritenga whakamātautau katoa.
Ngā Pātai Auau
Ko tēhea reta ka puta tuatahi mai i roto i te waehere pōraritanga SAR?
Ko te reta tuatahi e tohu ana i te pōraihana kua tukuna, ā, ko te reta tuarua e tohu ana i te pōraihana kua whiwhi. Ko te tikanga o te HV ko te tuku whakapae me te whiwhinga poutū.
He aha te rerekētanga i waenga i te SAR takirua-pol me te SAR tapawha-pol?
Ka hopukina e te Dual-pol ngā hongere e rua, ko te tikanga ko te HH+HV, ko te VV+VH rānei. Ka hopukina e te Quad-pol a HH, HV, VH me VV, ā, ka tiakina ngā whanaungatanga e hiahiatia ana mō te tātari polarimetric katoa.
He pai ake te kotahi te pōraritanga SAR i ngā wā katoa?
Kāo. Ko te aratau tino whai hua ka whakawhirinaki ki te ūnga, te roanga ngaru radar, te koki taunga, te whakataunga, ngā āhuatanga taiao me te whāinga tukatuka.
He aha i whai hua ai ngā hongere whakawhiti-pōti?
Ka taea e te HV, e te VH rānei te whakaatu i te marara e whakarerekē ana i te pōrarurarutanga taupatupatu, inā koa ko te marara rōrahi me ngā whāinga matatini hanganga pērā i te tipu.
Whakamutunga
Mā te whakapūtanga SAR e whakahaere te āhua o te whakamārama a te radar i tētahi ūnga me te āhua o te ine i te mara i whakahokia mai. He hongere whakapūtanga-tahi a HH me VV, ko HV me VH ia he whakapūtanga-whiti. Ka tukuna e te whakapūtanga-kotahi te whai huatanga, ka tāpirihia e te whakapūtanga-rua te wehewehe, ā, mā te whakapūtanga-whā katoa ka whakaratohia te huinga raraunga whakapūtanga raina tino oti. Me whai whakaaro ngātahi ki te aratau hopu, te pūnaha pūihi, te tikanga whakatikatika me ngā whakaritenga tono mō ngā hua tika.
Mō te kōwhiringa pūihi, te tautoko ine RF polarimetric rānei, arotakehia ngā RF MISOte āheinga whakamātautau pūihi or whakapā atu ki te tīma RF MISO.
Ngā Tohutoro me ngā Pānui Anō
Mō ētahi atu kōrero mō ngā antenna, tirohia:
Wā tuku: Pipiri-28-2024
