Ndeapi matatu akasiyana polarization modes eSAR?

1. Chii chinonzi SARpolarization?
Polarization: H horizontal polarization; V vertical polarization, kureva, iyo vibration kutungamira kwenzvimbo yemagetsi. Kana setiraiti ikatumira chiratidzo pasi, kutungamira kweredhiyo wave kunoshandiswa kunogona kuve munzira dzakawanda. Izvo zvinoshandiswa zvino ndezvi:

Horizontal polarization (H-horizontal): Horizontal polarization zvinoreva kuti kana setiraiti yatumira chiratidzo pasi, kwainoita vibration yeradio wave yakachinjika. Vertical polarization (V-vertical): Vertical polarization zvinoreva kuti kana setiraiti yatumira chiratidzo pasi, kutungamira kweredhiyo wave kwakamira kwakamira.

Electromagnetic wave transmission yakakamurwa kuita horizontal waves (H) uye vertical waves (V), uye reception yakakamurwawo kuita H uye V. Iyo radar system inoshandisa H uye V linear polarization inoshandisa peya yezviratidzo kumiririra kutapurirana uye kugamuchira polarization, saka inogona kuva nematanho anotevera — HH, VV, HV, VH.

(1) HH - yekufambisa yakachinjika uye yakachinjika kugamuchira

(2) VV - yekutumira yakatwasuka uye yakatwasuka kugamuchira

(3) HV - yekutumira yakachinjika uye yakatwasuka kugamuchira

(4) VH - yekutumira yakatwasuka uye yakachinjika kugamuchira

Iwo maviri ekutanga eaya masanganiswa epolarization anonzi akafanana polarizations nekuti kuendesa uye kugamuchira polarizations zvakafanana. Iwo maviri ekupedzisira masanganiswa anonzi muchinjiko polarizations nekuti kuendesa uye kugamuchira polarizations kune orthogonal kune mumwe nemumwe.

2. Chii chinonzi polarization, dual polarization, uye polarization yakazara muSAR?

Single polarization inoreva (HH) kana (VV), zvinoreva (kutenderera kutenderera uye kugamuchira kwakachinjika) kana (kutenderera kutenderera uye kugadzika kugashira) (kana uri kudzidza ndima yemeteorological radar, kazhinji (HH).

Dual polarization inoreva kuwedzera imwe polarization modhi kune imwe polarization modhi, senge (HH) yakachinjika kutapurirana uye yakachinjika kugamuchira + (HV) yakachinjika kutapurirana uye yakatwasuka kugamuchira.

Tekinoroji yakazara yepolarization ndiyo yakanyanya kuoma, inoda kutapurirana panguva imwe chete yeH uye V, ndiko kuti, iyo ina polarization modes ye (HH) (HV) (VV) (VH) iripo panguva imwe chete.

Radar masisitimu anogona kuve neakasiyana mazinga ekuoma kwepolarization:

(1) Single polarization: HH; VV; HV; VH

(2)Dual polarization: HH+HV; VV+VH; HH+VV

(3) Polarizations ina: HH+VV+HV+VH

Orthogonal polarization (kureva yakazara polarization) ma radar anoshandisa aya mapolarizations uye anoyera mutsauko wechikamu pakati pemachaneli pamwe neamplitude. Mamwe maviri-polarization radars anoyerawo mutsauko wechikamu pakati pezviteshi, sezvo chikamu ichi chinoita basa rakakosha mukubvisa ruzivo rwepolarization.

Radar setiraiti mifananidzo Panyaya yepolarization, zvinhu zvakasiyana zvinoonekwa zvinodzosera akasiyana mafungu epolarization kune akasiyana chiitiko mafungu epolarization. Naizvozvo, nzvimbo yekuona kure inogona kushandisa akawanda mabhendi kuwedzera ruzivo rwemukati, kana kushandisa akasiyana polarizations kusimudzira nekuvandudza iko kurongeka kwekuzivikanwa kwechinangwa.

3. Ungasarudza sei polarization mode yeSAR radar satellite?

Zvakaitika zvinoratidza kuti:

Kune zvikumbiro zvemugungwa, iyo HH polarization yeL band inonyanya kunetseka, nepo VV polarization yeC band iri nani;

Kune huswa husina kupararira uye migwagwa, horizontal polarization inoita kuti zvinhu zvive nemisiyano yakakura, saka SAR inoshandiswa pakuita mepu yepasi inoshandisa horizontal polarization; kune ivhu rine hukasha hwakakura kupfuura urefu hwesaisai, hapana shanduko iri pachena muHH kana VV.

Iyo echo simba rechinhu chimwe pasi pepolarizations yakasiyana yakasiyana, uye toni yemufananidzo yakasiyanawo, iyo inowedzera ruzivo rwekuziva chinangwa chechinhu. Kuenzanisa ruzivo rwepolarization yakafanana (HH, VV) uye cross-polarization (HV, VH) inogona kuwedzera zvakanyanya ruzivo rwemufananidzo weradar, uye mutsauko weruzivo pakati pepolarization echoes yezvinomera nezvimwe zvinhu zvakasiyana zvakanyanya kunzwisiswa kupfuura musiyano uripo mabhandi akasiyana.
Nokudaro, mukushandiswa kunoshanda, iyo yakakodzera polarization mode inogona kusarudzwa maererano nezvinodiwa zvakasiyana, uye kushandiswa kwakazara kwemazhinji polarization modes kunobatsira kuvandudza kurongeka kwechinhu.