1、實(shí)習(xí)報(bào)告三-衛(wèi)星位置與地面站接收范圍實(shí)習(xí)三衛(wèi)星位置和地面站接收范圍1 .實(shí)習(xí)目的1）理解地面站接收極軌衛(wèi)星的范圍。2）會(huì)判斷地面站接收到衛(wèi)星信號(hào)的起始時(shí)間。3）能計(jì)算出衛(wèi)星相對(duì)于接收站的方位角和仰角。2 .實(shí)習(xí)方案1）假設(shè)要在NUIST（G=32.2N,勵(lì)=118.5E）設(shè)置一極軌衛(wèi)星接收站。極軌衛(wèi)星軌道高度H=830km。取地球半徑R=6371km,計(jì)算該接收站的接收范圍&maxcos(max)=R/(R+H)2）在實(shí)習(xí)二”中的圖3-3上，標(biāo)出NUIST接收站的位置和接收范圍mmax,如圖4-1所示意。（為簡(jiǎn)單其間，接收范圍Smax用以接收站為圓心、半徑為smax的圓表示。可以在Ex

2、cel顯示的圖3-3上用工具繪圖來(lái)手工標(biāo)出）圖4-1星下點(diǎn)軌跡與地面站接收范圍的相對(duì)位置示意NUIST接收站的位置和接收范圍6max,也可以標(biāo)在如圖4-2所示的北半球底圖上（參考教材圖4.24標(biāo)出經(jīng)緯度刻度）。實(shí)習(xí)報(bào)告三-衛(wèi)星位置與地面站接收范圍圖4-2北半球底圖3 ）觀察圖4-1上的星下點(diǎn)軌跡與NUIST站接收范圍之間的關(guān)系。如果星下點(diǎn)軌跡經(jīng)過(guò)NUIST站接收范圍，則計(jì)算給出地面站可接收衛(wèi)星信號(hào)的起、始時(shí)間（注意：軌道報(bào)給出的升交點(diǎn)時(shí)間為世界時(shí)，北京時(shí)=世界時(shí)+8小時(shí)）。如果星下點(diǎn)軌跡不經(jīng)過(guò)NUIST站接收范圍，則將電子表格中星下點(diǎn)經(jīng)度”一列減去“截距”，再觀察圖4-1上的星下點(diǎn)軌跡與NUI

3、ST站接收范圍之間的關(guān)系，重復(fù)此過(guò)程，直到圖4-1上出現(xiàn)“星下點(diǎn)軌跡經(jīng)過(guò)NUIST站接收范圍”為止。出現(xiàn)“星下點(diǎn)軌跡經(jīng)過(guò)NUIST站接收范圍”時(shí)，請(qǐng)計(jì)算給出地面站可接收衛(wèi)星信號(hào)的起、始時(shí)間。4 ）利用上一步得到的電子表格中的數(shù)據(jù)（每2分鐘一次的星下點(diǎn)經(jīng)緯度（晨Ws）,用以下公式計(jì)算NUIST接收站每2分鐘一次的衛(wèi)星方位角a、仰角P。經(jīng)度差：&尸，LS一大圓J：、=arccos（sin0sinscos0cosscos）方位角：.sin：cosi-arcsi-n-fsin仰角：cos-R-arcta-n-Rhsin當(dāng)P=0時(shí)，cos=ReReh實(shí)習(xí)報(bào)告三-衛(wèi)星位置與地面站接收范圍此時(shí)的6為

4、&max=arccos()Reh注意:(1)EXCEL中可查“幫助數(shù)學(xué)和三角函數(shù)”中相關(guān)公式的語(yǔ)法。(2)用EXCEL計(jì)算三角函數(shù)值時(shí)，角度()要化作弧度(*3.14/180)。(3)計(jì)算中用到反余弦ACOS(number)、反正弦ASIN(number)、反正切ATAN(number)。弧度轉(zhuǎn)為度DEGREES(弧度)。5)在實(shí)習(xí)二”制作的電子表格中增加三列，分別用來(lái)填寫(xiě)上述計(jì)算得到的6、口、口。3.實(shí)習(xí)結(jié)果(1) cos(max)=R/(R+H)所以，H=830km,R=6371km,代入上式，可得：Smax=27.7947.父度經(jīng)隨度緯r(shí)l-'lv11，星下點(diǎn)緯度(+-如

5、)實(shí)習(xí)報(bào)告三-衛(wèi)星位置與地面站接收范圍(4)最后制作出的三列表格如下:daP141.5262824141.5262824-69.53751536140.5036712140.5036712-68.99102348138.4538663138.4538663-67.89490371135.5764295135.5764295-66.35456113131.9797887131.9797887-64.42624093127.7629743127.7629743-62.16070684123.1141351123.1141351-59.65636256118.0607702118.0607702-5

6、6.9249221473.9625489373.96254893-32.33290705107.336691107.336691-51.08933118101.6648548101.6648548-47.9762767495.8860643395.88606433-44.7806646290.1247294390.12472943-41.5658212584.2185101384.21851013-38.2336680978.2817254678.28172546-34.8384055372.4614154172.46141541-31.4540004666.5501552266.550155

7、22-27.9450508360.6538658160.65386581-24.3521211554.9126915954.91269159-20.7363210449.2530093149.25300931-17.0192701443.9232283843.92322838-13.3288739239.0086835939.00868359-9.69823313834.5674677634.56746776-69970433230.99704332-3.04880561528.5660606328.56606063-0.76169088127.7085424227.

8、708542420.08634669528.3956709928.39567099-0.59504359230.7217066830.72170668-2.79765605934.2440151434.24401514-5.88219998138.7291925238.72919252-9.48347199743.7306196343.73061963-13.1912010149.2614055249.26140552-17.0249220755.1832970355.18329703-20.9098790761.3053869761.30538697-24.7545120567.505686

9、2367.50568623-28.5179350573.8624589173.86245891-32.2744429880.3406023980.34060239-36.0217404886.8413481586.84134815-39.7184626193.3756484193.37564841-43.38372231100.0091879100.0091879-47.06336529106.5413407106.5413407-50.654040774/5實(shí)習(xí)報(bào)告三-衛(wèi)星位置與地面站接收范圍113.1415251119.7577241126.3469376132.8019688139.1332217145.3075939151.1181416156.4316776160.5640208163.0077709162.2354224.實(shí)習(xí)結(jié)語(yǔ)113.1415251119.7577241126.3469376132.8019688139.1332217145.3075939151.1181416156.4316776160.5640208163.0077709162.235422-54.25533896-57.84331217-61.39867057-64.86735775-68.25828888-71.5564