JP3612919B2

JP3612919B2 - Radiometer

Info

Publication number: JP3612919B2
Application number: JP02863297A
Authority: JP
Inventors: 保男玉井; 知将藤永
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 1997-02-13
Filing date: 1997-02-13
Publication date: 2005-01-26
Anticipated expiration: 2017-02-13
Also published as: JPH10227818A

Description

【０００１】
【発明の属する技術分野】
この発明は、人工衛星又は航空機等の飛翔体に搭載して地球表面や大気の観測を行う放射計に関するものである。
【０００２】
【従来の技術】
図９は、人工衛星に搭載して地球表面や大気を観測する従来の放射計を示す図であり、図において、１は放射計、２は観測用反射鏡、３は低温校正用反射鏡、４は高温校正源、５は一次放射器、６は受信機、７は信号処理部、８は回転機構、９は冷凍機、１０は断熱容器、１１は回転部、１２は地球、１３は低温校正時の校正信号となる約２．７Ｋである宇宙背景放射を放射する深宇宙である。図１０は観測時の信号の流れを示す図である。図１１は低温校正時の信号の流れを示す図である。図１２は高温校正時の信号の流れを示す図である。図１３は観測、低温校正、高温校正のタイミングを示す図である。
【０００３】
次に動作について説明する。図１０から図１３までの図を用いて説明する。地球１２の観測対象を走査して輝度温度を観測する放射計１は、観測用反射鏡２、一次放射器５、受信機６、信号処理部７を含む回転部９及び観測用反射鏡２を回転機構８により回転させている。この放射計１により測定される信号は、地球１２の表面の地面や海水等の自然界から放射される極めて微弱な雑音電波であり、受信機６の雑音温度を可能な限り下げることが必要なため、受信機６を冷凍機９で冷却した断熱容器内に収納して使用されている。また、外部熱環境等より低雑音受信機６の利得変動があるため、一定周期毎に低温校正源と高温校正源を観測して放射計の入出力を校正する必要があり、ここでは、従来は低校正源として約２．７Ｋである深宇宙１３からの宇宙背景放射を取得するために低温校正用反射鏡３を配し、高温校正源４としてヒータにより温度制御された電波吸収体を使用した場合で示している。この低温校正、高温校正、観測のタイミングは、図１３に一例を示すとおりであり、低温校正用反射鏡３及び高温校正源４は、機械的に一次放射器５の走査円弧上に設置しており、１周期毎に１回、一次放射器５が低温校正用反射鏡３の真下を通過する際、低温校正信号の取得を行い、高温校正源４の真下を通過する際、高温校正信号の取得を行うようになっている。先ず、観測時の信号の流れを図１０を用いて説明する。観測時には、地球１２の表面から放射された電力は、観測用反射鏡２を介して一次放射器５で受信される。一次放射器５で受信された受信信号は受信機６により増幅検波及び積分された後、信号処理器７によってＡ／Ｄ変換及び編集され、図示していない送信機により観測信号として地上に送出される。次に低温校正時の信号の流れを図１１を用いて説明する。低温校正時には、回転機構８により低温校正用反射鏡３が一次放射器５の真上に位置した時に、約２．７Ｋである深宇宙１３からの宇宙背景放射が低温校正用反射鏡３を介して一次放射器５で受信される。一次放射器５で受信した後の信号の流れは、観測時と同じである。
【０００４】
【発明が解決しようとする課題】
従来の放射計１は人工衛星又は航空機等の飛翔体に搭載し、受信出力の校正を行う場合には、宇宙背景放射を入力するための低温校正用反射鏡３及び高温校正源４を独立して配置し、それらを一定回転周期中に観測する必要があった。このため、低温校正用反射鏡３や高温校正源４を除く全ての機器を回転機構８により回転させ、一次放射器５を低温校正用反射鏡３及び高温校正源４からの電波が受信できる位置に制限する必要があった。このため、低温校正源となる宇宙空間と観測対象である地表の両方を観測できるよう、アンテナの切り替えを行う必要があり、アンテナの校正や駆動機構が複雑で大型化するという欠点があった。
【０００５】
また、低温校正用反射鏡３の視野を確保するために、機器配置、衛星搭載位置が制限されていた。また、低温校正用反射鏡３の視野内に衛星構体、主反射鏡を保持するためのストラット等が入り込み、クリアーな視界が確保できないことにより、低温校正信号が宇宙背景放射である約２．７Ｋからズレると共に、変動し軌道上での衛星構体、ストラット等の雑音温度の変動量の不確定性より、低温校正信号に誤差が生ずるという問題があった。
【０００６】
また、校正を行うタイミング及び校正データ数については、その必要性に関わらず、校正用反射鏡３や高温校正源４を一次放射器５で観測可能な位置関係に制限されており、回転機構８による一回転周期に一回の校正タイミングでのみ可能であり、最適な校正タイミングで校正を行うことができないという問題があった。
【０００７】
この発明は、上記のような課題を改善するためになされたものであり、独立した低温校正用反射鏡及び高温校正源を共に用いることなく、校正を可能とする放射計を提供しようとするものである。
【０００８】
【課題を解決するための手段】
第１の発明による放射計は、低温校正源を用いずに低温校正入力ができるように、観測用反射鏡と、第１の反射鏡と、第１の反射鏡駆動機構と、第２の反射鏡と、第２の反射鏡駆動機構と、冷凍機と、断熱容器と、一次放射器と、受信機と、信号処理器を具備したものである。
【０００９】
また、第２の発明による放射計は、低温校正源及び高温校正源を用いずに校正入力ができるように、観測用反射鏡と、反射鏡と、反射鏡駆動機構と、冷凍機と、一次放射器と、受信機と、信号処理器とを具備したものである。
【００１０】
また、第３の発明による放射計は、低温校正源及び高温校正源を用いずに校正入力ができるように、観測用反射鏡と、第１の反射鏡と、第１の反射鏡駆動機構と、第２の反射鏡と、第２の反射鏡駆動機構と、メッシュ型反射鏡と、メッシュ型反射鏡駆動機構と、冷凍機と、一次放射器と、受信機と、信号処理器とを具備したものである。
【００１１】
また、第４の発明による放射計は、低温校正源及び高温校正源を用いずに校正入力ができるように、観測用反射鏡と、反射鏡と、反射鏡駆動機構と、冷凍機と、一次放射器と、ＲＦスイッチと、無反射終端器と、受信機と、信号処理器とを具備したものである。
【００１２】
また、第５の発明による放射計は、低温校正源及び高温校正源を用いずに校正入力ができるように、観測用反射鏡と、反射鏡と、反射鏡駆動機構と、冷凍機と、一次放射器と、ＲＦスイッチと、ＲＦスイッチ駆動機構と、ホーンと、電波吸収体と、受信機と、信号処理器とを具備したものである。
【００１３】
【発明の実施の形態】
実施の形態１．
図１はこの発明の実施の形態１を示す図である。図１は、低温校正源反射鏡を用いずに校正が可能な放射計の構成を示す図であり、図において１４は反射鏡、１５は反射鏡駆動機構である。また、図２はこの発明の放射計の観測時の信号の流れを示す図である。図３は、この発明の放射計の低温校正時の信号の流れを示す図である。図４は、この発明の放射計の高温校正時の信号の流れを示す図である。
【００１４】
次に動作について、図２〜４を用いて説明する。観測時の信号の流れを図２を用いて説明する。観測時には、反射鏡１４は反射鏡駆動機構１５により、一次放射器５のビーム方向と平行で、地球１２表面から放射される雑音電波が、観測用反射鏡２で反射及び集光され一次放射器５に導かれるビーム方向を妨げない方向に設定制御され、地球１２表面から放射される雑音電波は、観測用反射鏡２により反射及び集光され一次放射器５に導かれる。一次放射器５に導かれた雑音電波は、断熱容器１０内に配置され冷却された受信機６に入力し増幅及び検波、積分された後、信号処理器７によってＡ／Ｄ変換及び編集された後、図示していない送信機により観測信号として地上に送出される。低温校正時の信号の流れを図４を用いて説明する。低温校正時には、反射鏡駆動機構１５を用いて反射鏡１４を一次放射器５のビーム方向と垂直で直交した方向に制御する。この時、観測用反射鏡２及び高温校正源４からの電波は、前記反射鏡１４に遮られ、一次放射器５の視野内には反射鏡１４のみが介在することとなり、一次放射器５で受信される電波は冷却された一次放射器５自体が発生する熱雑音と反射鏡１４の熱雑音のみとなる。一次放射器５の熱雑音及び反射鏡１４の熱雑音は、冷凍機９により冷却された一次放射器５及び反射鏡１４の物理温度と等価となり、冷凍機により冷却された物理温度が一次放射器５に入力される。冷凍機９により冷却される温度を例えば４Ｋ程度の極低温に冷却するように制御することにより、４Ｋ相当する電波が一次放射器に低温校正信号として一次放射器に入力される。受信された受信信号は、観測時と同じ処理により地上に送出される。また、高温校正時には、高温校正源４が機械的に一次放射器５の走査円弧上に設置されているため、図３に示すように回転機構８の制御により高温校正源４の直下に一次放射器５が位置する時に、高温校正源からの放射電波を一次放射器５で受信する。受信後の信号の流れは観測信号の同様に送出される。
【００１５】
実施の形態２．
図５は、この発明の実施の形態２を示す図である。図において、１４ａ，１４ｂは反射鏡、１５ａ，１５ｂは反射鏡駆動機構である。
【００１６】
次に動作について、図５を用いて、観測時、低温校正時及び高温校正時に信号入力の状況を説明する。観測時には、反射鏡駆動機構１５ａ及び１５ｂにより反射鏡１４ａ及び１４ｂを一次放射器５のビーム方向と平行で、地球１２表面から放射される雑音電波が観測用反射鏡２で反射及び集光され一次放射器５に導かれるビーム方向を妨げない方向である１４ａ´及び１４ｂ´の位置に設定制御され、地球１２表面から放射される雑音電波は、観測用反射鏡２により反射集光され一次放射器５に導かれる。導かれた雑音電波は、断熱容器１０内に配置され冷却された受信機６に入力し増幅及び検波、積分された後、信号処理器７によってＡ／Ｄ変換及び編集された後、図示していない送信機により観測信号として地上に送出される。また、低温校正時には、反射鏡駆動機構１５ａ，１５ｂを用いて反射鏡１４ａ，１４ｂを一次放射器５のビーム方向と垂直で直交した方向に制御される。この低温校正時においては、観測用反射鏡から入射する雑音電波は前記反射鏡１４ｂに遮られ、一次放射器５には入力せずに、冷却された一次放射器５自身の熱雑音と反射鏡１４ａが有する熱雑音の和となる。一次放射器５の熱雑音及び反射鏡１４ａの熱雑音は、冷凍機９により冷却された一次放射器５及び反射鏡１４ａの物理温度と等価となり、冷凍機により冷却された一次放射器５及び反射鏡１４ａの各物理温度の和が一次放射器５に入力される。従って、冷凍機９により冷却される温度を例えば４Ｋ程度の極低温となるように断熱容器１０内で制御することにより、４Ｋ相当の電波が一次放射器５に低温校正信号として一次放射器５に入力されることとなる。受信された受信信号は、観測時と同じ処理により地上に送出される。また、高温校正時には、反射鏡駆動機構１５ａにより反射鏡１４ａの鏡面方向を一次放射のビーム方向と平行になるように制御すると共に、反射鏡駆動機構１５ｂにより反射鏡１４ｂの鏡面方向を一次放射器５のビーム方向と垂直で直交する方向である１４ｂ´の位置に設定されるため、一次放射器５の視野内には反射鏡１４ｂのみが存在し反射鏡１４ｂの物理温度に対応する雑音温度が入力する。反射鏡１４ｂは断熱容器の外部にあり３００Ｋ程度の物理温度にヒータ等により温度制御することにより、３００Ｋに相当する電波が高温校正信号として、一次放射器５に入力される。一次放射器５に入力した高温校正信号は、観測時と同様の処理により地上に送出される。
【００１７】
実施の形態３．
図６は、この発明の実施の形態３を示す図である。図において、１４ａ、１４ｂは反射鏡、１５ａ，１５ｂは反射鏡駆動機構、１６はメッシュ型反射鏡、１７はメッシュ型反射鏡駆動機構である。
【００１８】
次に動作について、図６を用いて、観測時、低温校正時及び高温校正時毎に説明する。先ず、観測時について説明する。観測時には、冷凍機９で冷却され断熱容器１０内に収納された反射鏡１４ａ及びメッシュ型反射鏡１６、更に断熱容器１０外に設置した反射鏡１４ｂを全て反射鏡駆動機構１５ａ、メッシュ反射鏡駆動機構１７及び反射鏡駆動機構１５ｂにより一次放射器５のビーム方向と平行な位置に設定される。このため、地球１２表面から放射される雑音電波は観測用反射鏡２で反射及び集光され、妨げられることなく一次放射器５に導かれる。一次放射器５に導かれた雑音電波は、断熱容器１０内に配置された受信機６に入力し増幅及び検波、積分された後、信号処理器７によってＡ／Ｄ変換及び編集された後、図示していない送信機により観測信号として地上に送出される。次に、低温校正時には反射鏡駆動機構１５ａを用いて反射鏡１４ａを一次放射器５のビーム方向と垂直で直交した方向に位置するように制御される。このため低温校正時においては、観測用反射鏡２から入射する雑音電波は前記反射鏡１４ａに遮られ一次放射器５には入力せずに、一次放射器５で受信される信号は、冷却された一次放射器５自身の熱雑音と反射鏡１４ａが有する熱雑音の和となる。一次放射器５の熱雑音及び反射鏡１４ａの熱雑音は、冷凍機９により冷却された一次放射器５及び反射鏡１４ａの物理温度と等価となり、冷凍機９により冷却された一次放射器５と反射鏡１４ａの各物理温度の和が一次放射器５に入力される。従って、冷凍機９により冷却される温度を例えば４Ｋ程度の極低温となるように断熱容器１０内で制御することにより、４Ｋ相当の電波が一次放射器５に低温校正信号として一次放射器５に入力されることとなる。受信された受信信号は、観測時と同じ処理により地上に送出される。また、高温校正時には、反射鏡駆動機構１５ａにより反射鏡１４ａの鏡面方向を一次放射のビーム方向と平行になる反射鏡１４ａ´の位置となるように制御し、併せてメッシュ型反射鏡駆動機構１７によりメッシュ型反射鏡１６を一次放射器５のビーム方向と平行となる方向に設定すると共に、反射鏡１４ｂの鏡面方向を一次放射器５のビーム方向と垂直で直交する方向である１４ｂ´の位置に設定することにより、一次放射器５の視野内には反射鏡１４ｂのみが存在し反射鏡１４ｂの物理温度に対応する雑音温度が入力する。反射鏡１４ｂは断熱容器の外部にあり３００Ｋ程度の物理温度にヒータ等により温度制御することにより、３００Ｋに相当する電波が高温校正信号として、一次放射器５に入力される。一次放射器５に入力した高温校正信号は、観測時と同様の処理により地上に送出される。更に、高温校正時には、反射鏡駆動機構１５ａにより反射鏡１４ａの鏡面方向を一次放射のビーム方向と平行となる反射鏡１４ａ´となる位置に制御し、メッシュ型反射鏡駆動機構１７によりメッシュ型反射鏡１６を一次放射器５のビーム方向と直交する方向であるメッシュ反射鏡１６´の位置に制御すると共に反射鏡１４ａの鏡面方向を一次放射器５のビーム方向と垂直で直交する方向である１４ｂ´の位置に設定されるため、一次放射器５の視野内には反射鏡１４ｂ´及びメッシュ反射鏡１６´が存在し物理温度に対応する雑音温度が入力する。反射鏡１４ｂは断熱容器１０の外部にあり３００Ｋ程度の物理温度にヒータ等により温度制御されているが、加えてメッシュ反射鏡１６´の物理温度が加算されメッシュ反射鏡の物理温度が合計温度が例えば２００Ｋになるように設定しておくことにより、２００Ｋに相当する雑音電波を高温校正信号として、一次放射器５に入力することができる。従って、高温校正源の温度を２種類設定することが可能ならしめている。一次放射器５に入力した高温校正信号は、観測時と同様の処理により地上に送出される。
【００１９】
実施の形態４．
図７は、この発明の実施の形態４を示す図である。図において、１４は反射鏡、１５は反射鏡駆動機構、１８はＲＦスイッチ、１９は無反射終端器、２０はＲＦスイッチ制御器である。
【００２０】
次に動作について、図７を用いて説明する。観測時には、反射鏡駆動機構１５により反射鏡１４を一次放射器５のビーム方向と平行である反射鏡１４´の位置に設定するように制御されると共に、ＲＦスイッチ制御器２０で一次放射器５からの信号が受信機６に入力するように制御される。従って、地球１２表面から放射される雑音電波は、観測用反射鏡２により反射及び集光され一次放射器５に導かれる。一次放射器５に導かれた雑音電波は、断熱容器１０内に配置され冷却された受信機６に入力し増幅及び検波、積分された後、信号処理器７によってＡ／Ｄ変換及び編集された後、図示していない送信機により観測信号として地上に送出される。次に、低温校正時には、ＲＦスイッチ制御器２０により受信機６が無反射終端器１９側に接続されるようにＲＦスイッチ１８を切り換え制御される。受信機６には無反射終端器１９の物理温度に相当する雑音電波が入力されることになり、冷凍機９により冷却される温度を例えば４Ｋ程度の極低温となるように断熱容器１０内に収納した無反射終端器１９の温度を制御することにより、４Ｋ相当の雑音電波が一次放射器５に低温校正信号として一次放射器５に入力されることとなる。受信された受信信号は、観測時と同じ処理により地上に送出される。また、高温校正時には、ＲＦスイッチ制御器２０を用いて受信機６が観測時と同様に一次放射器５に接続されるように切り換え制御されると共に、反射鏡駆動機構１５により反射鏡１４の鏡面方向を一次放射のビーム方向と直交する位置に設定されるように制御される。このため、一次放射器５には反射鏡１４の物理温度に対応する雑音温度が入力する。反射鏡１４は、断熱容器１０の外部にありヒータ等を用いて３００Ｋ程度の物理温度に温度制御されることにより、物理温度３００Ｋに相当する電波が高温校正信号が一次放射器５に入力される。一次放射器５に入力した高温校正信号は、観測時と同様の処理により地上に送出される。
【００２１】
実施の形態５．
図８は、この発明の実施の形態５を示す図である。図において、１４は反射鏡、１５は反射鏡駆動機構、１６はＲＦスイッチ、２０はＲＦスイッチ制御器、２１はホーン、２２は電波吸収体である。
【００２２】
次に動作について、図８を用いて説明する。観測時には、反射鏡駆動機構１５により反射鏡１４を一次放射器５のビーム方向と平行である反射鏡１４´の位置に設定するように制御されると共に、ＲＦスイッチ制御器２０を用いて一次放射器５からの信号が受信機６に入力するようにＲＦスイッチ１６を切り換え制御される。地球１２表面から放射される雑音電波は、観測用反射鏡２により反射及び集光され一次放射器５に導かれる。一次放射器５に導かれた雑音電波は、受信機６に入力し増幅及び検波、積分された後、信号処理器７によってＡ／Ｄ変換及び編集された後、図示していない送信機により観測信号として地上に送出される。次に、低温校正時には、ＲＦスイッチ制御器２０により受信機６がホーン２１からの信号が受信機６に接続され入力するようにＲＦスイッチ１６が切り換え制御される。ホーン２１の前面に冷凍機９で冷却された電波吸収体２２を配置することにより、ホーン２１には電波吸収体２２の物理温度に相当する雑音電波が受信され、ＲＦスイッチ１６を介して受信機６に入力する。ここで、電波吸収体２２の冷却温度が例えば４Ｋ程度の極低温となるように断熱容器１０内に収納した無反射終端器の温度を制御されることにより、４Ｋ相当の雑音電波がホーン２１及びＲＦスイッチ１６を介して低温校正信号として受信機６に入力されることとなる。受信された受信信号は、観測時と同じ処理により地上に送出される。また、高温校正時には、ＲＦスイッチ制御器２０を用いて受信機６が観測時と同様に一次放射器５に接続されるように切り換え制御されると共に、反射鏡駆動機構１５により反射鏡１４の鏡面方向を一次放射のビーム方向と直交する位置に設定されるように制御される。このため、一次放射器５には反射鏡１４の物理温度に対応する雑音温度が入力する。反射鏡１４は、断熱容器１０の外部にありヒータ等を用いて３００Ｋ程度の物理温度に温度制御されることにより、物理温度３００Ｋに相当する電波が高温校正信号が一次放射器５に入力される。一次放射器５に入力した高温校正信号は、観測時と同様の処理により地上に送出される。
【００２３】
【発明の効果】
第１の発明によれば、地上からの電波を反射する観測用反射鏡と、一次放射器と、一次放射器の前に配置した反射鏡と、反射鏡を一次放射器のビーム方向と平行及び直交する方向の２状態に設定するための駆動機構と、受信機と、一次放射器及び反射鏡と受信機を冷却するための冷凍機と、一次放射器及び反射鏡と受信機を外界から遮断する断熱容器と、高温校正源と、信号処理器を具備することにより、低温校正用反射鏡を用いることなく冷凍機の冷却により生成させた低温校正雑音の入力が可能となり、低温校正用反射鏡の介在に伴う観測幅の制約を受けない観測が実施できるという効果がある。また、冷却機の冷却により安定した低温校正源を確保できることから、校正精度が向上ができるという効果がある。更に、走査周期と無関係に校正タイミングを設定でき、最適な校正タイミングでのデータ取得が可能となる効果がある。
【００２４】
また、第２の発明によれば、地上からの電波を反射する観測用反射鏡と、一次放射器と、観測用反射鏡と一次放射器の間に配置した第１の反射鏡及び第２の反射鏡と、一次放射器のビーム方向と平行及び直交する方向の２状態に設定するための反射鏡駆動機構と、受信機と、一次放射器及び反射鏡と受信機を冷却するための冷凍機と、一次放射器及び反射鏡と受信機を外界から熱的に遮断するための断熱容器と、信号処理器を具備することにより、高温校正源、低温校正用反射鏡及び回転機構を用いることなく低温校正雑音及び高温校正雑音の入力が可能となり、高温校正源及び低温校正用反射鏡の配置設定に伴う観測幅の制約を受けない観測が実施できると共に、回転機構が無くなることから簡易な放射計を構成できるとう効果がある。また、冷却機の冷却により安定した低温校正源を確保できることから、校正精度が向上ができるという効果がある。更に、走査周期と無関係に校正タイミングを設定でき、最適な校正タイミングでのデータ取得が可能となる効果がある。
【００２５】
また、第３の発明によれば、地上からの電波を反射する観測用反射鏡と、一次放射器と、観測用反射鏡と一次放射器の間に配置した第１の反射鏡と、第２の反射鏡と、メッシュ型の反射鏡と、反射鏡とメッシュ型反射鏡を一次放射器のビーム方向と平行及び直交する方向の２状態に設定するための反射鏡駆動機構と、メッシュ型反射鏡駆動機構と、受信機と、一次放射器及び反射鏡と受信機を冷却するための冷凍機と、一次放射器及び反射鏡と受信機を外界から熱的に遮断するための断熱容器と、信号処理器を具備することにより、高温校正源、低温校正用反射鏡及び回転機構を用いることなく低温校正雑音及び高温校正雑音の入力に加えて中間温度の校正が可能となり、校正精度を向上することが可能となると共に、高温校正源及び低温校正用反射鏡の配置設定に伴う観測幅の制約を受けない観測が実施でき簡易な放射計を構成できるという効果がある。更に、走査周期と無関係に校正タイミングを設定でき、最適な校正タイミングでのデータ取得が可能となる効果がある。
【００２６】
また、第４の発明によれば、地上からの電波を反射する観測用反射鏡と、一次放射器と、観測用反射鏡と一次放射器の間に配置した反射鏡と、一次放射器のビーム方向と平行及び直交する方向の２状態に設定するための反射鏡駆動機構と、無反射終端器と、ＲＦスイッチと、受信機と、一次放射器、反射鏡、無反射終端器とＲＦスイッチ及び受信機を冷却するための冷凍機と、一次放射器、反射鏡、無反射終端器とＲＦスイッチ及び受信機を外界から熱的に遮断し収納するための断熱容器と、信号処理器を具備することにより、高温校正源、低温校正用反射鏡及び回転機構を用いることなく低温校正雑音及び高温校正雑音の入力が可能となり、高温校正源及び低温校正用反射鏡の配置設定に伴う観測幅の制約を受けず回転機構が無い簡易な放射計を構成できるという効果がある。また、冷却機の利用により安定した低温校正源が確保でき、校正精度が向上できるという効果がある。
【００２７】
また、第５の発明によれば、地上からの電波を反射する観測用反射鏡と、一次放射器と、観測用反射鏡と一次放射器の間に配置した反射鏡と、一次放射器のビーム方向と平行及び直交する方向の２状態に設定するための反射鏡駆動機構と、電波吸収体と、ＲＦスイッチと、ＲＦスイッチ駆動機構と、受信機と、一次放射器と、反射鏡と、ＲＦスイッチ及び受信機を冷却するための冷凍機と、一次放射器、反射鏡、電波吸収体、ＲＦスイッチ及び受信機を外界から熱的に遮断し収納するための断熱容器と、信号処理器とを具備することにより、高温校正源、低温校正用反射鏡及び回転機構を用いることなく低温校正雑音及び高温校正雑音の入力が可能となり、高温校正源及び低温校正用反射鏡の配置設定に伴う観測幅の制約を受けず回転機構が無い簡易な放射計を構成できるという効果がある。また、冷凍機の利用による安定した低温校正源が確保でき、校正精度が向上できるという効果がある。
【図面の簡単な説明】
【図１】この発明の実施例１を示す放射計の構成例を示す図である。
【図２】この発明の実施例１を示す放射計の観測時を示す図である。
【図３】この発明の実施例１を示す放射計の低温校正時を示す図である。
【図４】この発明の実施例１を示す放射計の高温校正時を示す図である。
【図５】この発明の実施例２を示す放射計の構成例を示す図である。
【図６】この発明の実施例３を示す放射計の構成例を示す図である。
【図７】この発明の実施例４を示す放射計の構成例を示す図である。
【図８】この発明の実施例５を示す放射計の構成例を示す図である。
【図９】従来の放射計の構成例を示す図である。
【図１０】従来の放射計の観測時を示す図である。
【図１１】従来の放射計の低温構成時を示す図である。
【図１２】従来の放射計の高温構成時を示す図である。
【図１３】従来の放射計の観測タイミングを示す図である。
【符号の説明】
１放射計、２観測用反射鏡、３低温校正用反射鏡、４高温校正源、５一次放射器、６受信機、７信号処理器、８回転機構、９冷凍機、１０断熱容器、１１回転部、１２地球、１３深宇宙、１４反射鏡、１５反射鏡駆動機構、１６メッシュ型反射鏡、１７メッシュ型反射鏡駆動機構、１８ＲＦスイッチ、１９無反射終端器、２０ＲＦスイッチ制御器、２１ホーン、２２電波吸収体。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a radiometer that is mounted on a flying object such as an artificial satellite or an aircraft and observes the surface of the earth and the atmosphere.
[0002]
[Prior art]
FIG. 9 is a diagram showing a conventional radiometer that is mounted on an artificial satellite and observes the surface of the earth and the atmosphere. In the figure, 1 is a radiometer, 2 is a reflector for observation, 3 is a reflector for low-temperature calibration, 4 is a high-temperature calibration source, 5 is a primary radiator, 6 is a receiver, 7 is a signal processing unit, 8 is a rotating mechanism, 9 is a refrigerator, 10 is an insulated container, 11 is a rotating unit, 12 is the earth, and 13 is a low temperature. It is a deep space that emits a cosmic background radiation of about 2.7K that becomes a calibration signal at the time of calibration. FIG. 10 is a diagram showing a signal flow during observation. FIG. 11 is a diagram illustrating a signal flow during low-temperature calibration. FIG. 12 is a diagram showing a signal flow during high-temperature calibration. FIG. 13 is a diagram showing the timing of observation, low temperature calibration, and high temperature calibration.
[0003]
Next, the operation will be described. This will be described with reference to FIGS. 10 to 13. A radiometer 1 that scans an observation target of the earth 12 and observes a luminance temperature includes an observation reflector 2, a primary radiator 5, a receiver 6, a rotating unit 9 including a signal processing unit 7, and an observation reflector 2. It is rotated by the rotation mechanism 8. The signal measured by the radiometer 1 is extremely weak noise radio waves radiated from the natural world such as the surface of the earth 12 and seawater, and it is necessary to reduce the noise temperature of the receiver 6 as much as possible. The receiver 6 is housed in a heat insulating container cooled by a refrigerator 9 and used. Further, since there is a gain fluctuation of the low noise receiver 6 due to an external thermal environment or the like, it is necessary to calibrate the input / output of the radiometer by observing the low temperature calibration source and the high temperature calibration source at regular intervals. Uses a low-temperature calibration reflector 3 to obtain a cosmic background radiation from the deep space 13 which is about 2.7 K as a low calibration source, and uses a radio wave absorber whose temperature is controlled by a heater as the high-temperature calibration source 4 Shown in case. The timing of this low temperature calibration, high temperature calibration, and observation is as shown in FIG. 13. The low temperature calibration reflector 3 and the high temperature calibration source 4 are mechanically installed on the scanning arc of the primary radiator 5. When the primary radiator 5 passes directly under the low-temperature calibration reflector 3 once per cycle, a low-temperature calibration signal is acquired, and when the primary radiator 5 passes directly under the high-temperature calibration source 4, Get to get. First, the flow of signals during observation will be described with reference to FIG. At the time of observation, the power radiated from the surface of the earth 12 is received by the primary radiator 5 via the observation reflecting mirror 2. The received signal received by the primary radiator 5 is amplified and detected and integrated by the receiver 6, then A / D converted and edited by the signal processor 7, and sent to the ground as an observation signal by a transmitter (not shown). The Next, the signal flow during low-temperature calibration will be described with reference to FIG. At the time of low-temperature calibration, when the reflector 3 for low-temperature calibration is positioned directly above the primary radiator 5 by the rotation mechanism 8, the cosmic background radiation from the deep space 13 of about 2.7 K passes through the reflector 3 for low-temperature calibration. And received by the primary radiator 5. The signal flow after reception by the primary radiator 5 is the same as that during observation.
[0004]
[Problems to be solved by the invention]
The conventional radiometer 1 is mounted on a flying object such as an artificial satellite or an aircraft, and when calibrating the reception output, the low-temperature calibration reflector 3 and the high-temperature calibration source 4 for inputting the cosmic background radiation are independently provided. It was necessary to observe them during a fixed rotation period. Therefore, all devices except the low-temperature calibration reflector 3 and the high-temperature calibration source 4 are rotated by the rotation mechanism 8 so that the primary radiator 5 can receive radio waves from the low-temperature calibration reflector 3 and the high-temperature calibration source 4. It was necessary to limit to. For this reason, it is necessary to switch antennas so that both the outer space as a low-temperature calibration source and the ground surface to be observed can be observed, and the antenna calibration and drive mechanism are complicated and large.
[0005]
In addition, in order to secure the field of view of the low-temperature calibration reflector 3, the arrangement of the equipment and the position where the satellite is mounted are limited. In addition, the satellite structure, struts for holding the main reflector, etc. enter the field of view of the low-temperature calibration reflector 3, and a clear field of view cannot be secured. There is a problem that an error occurs in the low-temperature calibration signal due to the uncertainty of the fluctuation amount of the noise temperature of the satellite structure, strut and the like in the orbit.
[0006]
In addition, the calibration timing and the number of calibration data are limited to the positional relationship in which the calibration reflector 3 and the high-temperature calibration source 4 can be observed by the primary radiator 5 regardless of the necessity. This is possible only with one calibration timing per rotation cycle, and there is a problem that calibration cannot be performed with the optimum calibration timing.
[0007]
The present invention has been made to improve the above-described problems, and is intended to provide a radiometer that can be calibrated without using an independent low-temperature calibration reflector and a high-temperature calibration source. It is.
[0008]
[Means for Solving the Problems]
The radiometer according to the first aspect of the invention provides an observation reflector, a first reflector, a first reflector driving mechanism, and a second reflector so that a low-temperature calibration input can be performed without using a low-temperature calibration source. A mirror, a second reflecting mirror driving mechanism, a refrigerator, a heat insulating container, a primary radiator, a receiver, and a signal processor are provided.
[0009]
In addition, the radiometer according to the second invention is provided with an observation reflecting mirror, a reflecting mirror, a reflecting mirror driving mechanism, a refrigerator, and a primary so that calibration input can be performed without using a low temperature calibration source and a high temperature calibration source. A radiator, a receiver, and a signal processor are provided.
[0010]
In addition, the radiometer according to the third aspect of the invention provides an observation reflecting mirror, a first reflecting mirror, and a first reflecting mirror driving mechanism so that calibration input can be performed without using a low temperature calibration source and a high temperature calibration source. A second reflector, a second reflector driving mechanism, a mesh reflector, a mesh reflector driving mechanism, a refrigerator, a primary radiator, a receiver, and a signal processor. It is what you did.
[0011]
In addition, the radiometer according to the fourth invention is provided with an observation reflecting mirror, a reflecting mirror, a reflecting mirror driving mechanism, a refrigerator, and a primary so that calibration input can be performed without using a low temperature calibration source and a high temperature calibration source. A radiator, an RF switch, a reflection-free terminator, a receiver, and a signal processor are provided.
[0012]
In addition, the radiometer according to the fifth aspect of the present invention provides an observation reflector, reflector, reflector drive mechanism, refrigerator, primary unit so that calibration input can be performed without using a low-temperature calibration source and a high-temperature calibration source. A radiator, an RF switch, an RF switch driving mechanism, a horn, a radio wave absorber, a receiver, and a signal processor are provided.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
FIG. 1 is a diagram showing Embodiment 1 of the present invention. FIG. 1 is a diagram showing a configuration of a radiometer that can be calibrated without using a low-temperature calibration source reflecting mirror, in which 14 is a reflecting mirror, and 15 is a reflecting mirror driving mechanism. FIG. 2 is a diagram showing a signal flow during observation by the radiometer of the present invention. FIG. 3 is a diagram showing a signal flow during low-temperature calibration of the radiometer of the present invention. FIG. 4 is a diagram showing a signal flow at the time of high-temperature calibration of the radiometer of the present invention.
[0014]
Next, the operation will be described with reference to FIGS. The signal flow during observation will be described with reference to FIG. At the time of observation, the reflecting mirror 14 is parallel to the beam direction of the primary radiator 5 by the reflecting mirror driving mechanism 15, and the noise radio wave radiated from the surface of the earth 12 is reflected and condensed by the observation reflecting mirror 2 and is reflected by the primary radiator. The noise radio wave radiated from the surface of the earth 12 is set and controlled in a direction that does not interfere with the beam direction guided to 5, reflected and collected by the observation reflecting mirror 2, and guided to the primary radiator 5. The noise radio wave guided to the primary radiator 5 is input into the cooled receiver 6 placed in the heat insulating container 10, amplified, detected, integrated, and then A / D converted and edited by the signal processor 7. Thereafter, it is sent to the ground as an observation signal by a transmitter (not shown). A signal flow during low-temperature calibration will be described with reference to FIG. At the time of low-temperature calibration, the reflector 14 is controlled in a direction perpendicular to and orthogonal to the beam direction of the primary radiator 5 using the reflector driving mechanism 15. At this time, radio waves from the observation reflecting mirror 2 and the high-temperature calibration source 4 are blocked by the reflecting mirror 14, and only the reflecting mirror 14 is interposed in the field of view of the primary radiator 5. The received radio waves are only thermal noise generated by the cooled primary radiator 5 itself and thermal noise of the reflecting mirror 14. The thermal noise of the primary radiator 5 and the thermal noise of the reflector 14 are equivalent to the physical temperatures of the primary radiator 5 and the reflector 14 cooled by the refrigerator 9, and the physical temperature cooled by the refrigerator is the primary radiator. 5 is input. By controlling the temperature cooled by the refrigerator 9 to be, for example, an extremely low temperature of about 4K, a radio wave corresponding to 4K is input to the primary radiator as a low-temperature calibration signal. The received signal is sent to the ground by the same processing as that at the time of observation. At the time of high temperature calibration, since the high temperature calibration source 4 is mechanically installed on the scanning arc of the primary radiator 5, the primary radiation is directly below the high temperature calibration source 4 by the control of the rotating mechanism 8 as shown in FIG. When the device 5 is located, the primary radiator 5 receives the radio wave from the high temperature calibration source. The signal flow after reception is sent in the same manner as the observation signal.
[0015]
Embodiment 2. FIG.
FIG. 5 is a diagram showing a second embodiment of the present invention. In the figure, 14a and 14b are reflecting mirrors, and 15a and 15b are reflecting mirror driving mechanisms.
[0016]
Next, the operation of the signal will be described with reference to FIG. 5 at the time of observation, low temperature calibration, and high temperature calibration. At the time of observation, the reflecting mirrors 14a and 14b are parallel to the beam direction of the primary radiator 5 by the reflecting mirror driving mechanisms 15a and 15b, and the noise radio waves radiated from the surface of the earth 12 are reflected and collected by the reflecting reflector 2 for the primary. The noise radio waves radiated from the surface of the earth 12 are set and controlled at positions 14a 'and 14b' which are directions that do not disturb the direction of the beam guided to the radiator 5, and are reflected and collected by the observation reflecting mirror 2 to be a primary radiator. Guided to 5. The introduced noise radio wave is input to the cooled receiver 6 placed in the heat insulating container 10, amplified, detected, integrated, A / D converted and edited by the signal processor 7, and then illustrated. Not sent to the ground as an observation signal by a transmitter. At the time of low-temperature calibration, the reflecting mirrors 14a and 14b are controlled in a direction perpendicular to and orthogonal to the beam direction of the primary radiator 5 using the reflecting mirror driving mechanisms 15a and 15b. At the time of this low-temperature calibration, the noise radio wave incident from the observation reflecting mirror is blocked by the reflecting mirror 14b and is not input to the primary radiator 5, but the thermal noise of the cooled primary radiator 5 itself and the reflecting mirror. It becomes the sum of the thermal noise which 14a has. The thermal noise of the primary radiator 5 and the thermal noise of the reflector 14a are equivalent to the physical temperatures of the primary radiator 5 and the reflector 14a cooled by the refrigerator 9, and the primary radiator 5 and the reflection cooled by the refrigerator. The sum of the physical temperatures of the mirror 14 a is input to the primary radiator 5. Therefore, by controlling the temperature cooled by the refrigerator 9 in the heat insulating container 10 so as to be an extremely low temperature of about 4K, for example, a radio wave equivalent to 4K is sent to the primary radiator 5 as a low-temperature calibration signal. Will be entered. The received signal is sent to the ground by the same processing as that at the time of observation. At the time of high temperature calibration, the mirror surface direction of the reflecting mirror 14a is controlled to be parallel to the beam direction of the primary radiation by the reflecting mirror driving mechanism 15a, and the mirror surface direction of the reflecting mirror 14b is controlled by the reflecting mirror driving mechanism 15b. Therefore, only the reflecting mirror 14b exists in the visual field of the primary radiator 5, and the noise temperature corresponding to the physical temperature of the reflecting mirror 14b is set. input. The reflecting mirror 14b is outside the heat insulating container and is controlled to a physical temperature of about 300K by a heater or the like, so that a radio wave corresponding to 300K is input to the primary radiator 5 as a high-temperature calibration signal. The high-temperature calibration signal input to the primary radiator 5 is sent to the ground by the same processing as at the time of observation.
[0017]
Embodiment 3 FIG.
FIG. 6 is a diagram showing a third embodiment of the present invention. In the drawing, 14a and 14b are reflecting mirrors, 15a and 15b are reflecting mirror driving mechanisms, 16 is a mesh type reflecting mirror, and 17 is a mesh type reflecting mirror driving mechanism.
[0018]
Next, the operation will be described for each observation, low temperature calibration, and high temperature calibration with reference to FIG. First, the observation time will be described. At the time of observation, the reflecting mirror 14a and the mesh type reflecting mirror 16 that are cooled by the refrigerator 9 and stored in the heat insulating container 10, and the reflecting mirror 14b installed outside the heat insulating container 10 are all driven by the reflecting mirror driving mechanism 15a and the mesh reflecting mirror. The position is set parallel to the beam direction of the primary radiator 5 by the mechanism 17 and the reflector driving mechanism 15b. For this reason, the noise radio wave radiated from the surface of the earth 12 is reflected and collected by the observation reflecting mirror 2 and guided to the primary radiator 5 without being disturbed. The noise radio wave guided to the primary radiator 5 is input to the receiver 6 disposed in the heat insulating container 10, amplified, detected, integrated, A / D converted and edited by the signal processor 7, It is sent to the ground as an observation signal by a transmitter (not shown). Next, at the time of low temperature calibration, the reflecting mirror drive mechanism 15a is used to control the reflecting mirror 14a so as to be positioned in a direction perpendicular to and orthogonal to the beam direction of the primary radiator 5. Therefore, at the time of low-temperature calibration, the noise radio wave incident from the observation reflecting mirror 2 is blocked by the reflecting mirror 14a and is not input to the primary radiator 5, but the signal received by the primary radiator 5 is cooled. Further, it is the sum of the thermal noise of the primary radiator 5 itself and the thermal noise of the reflecting mirror 14a. The thermal noise of the primary radiator 5 and the thermal noise of the reflecting mirror 14a are equivalent to the physical temperatures of the primary radiator 5 and the reflecting mirror 14a cooled by the refrigerator 9, and the primary radiator 5 cooled by the refrigerator 9 and The sum of the physical temperatures of the reflecting mirror 14 a is input to the primary radiator 5. Therefore, by controlling the temperature cooled by the refrigerator 9 in the heat insulating container 10 so as to be an extremely low temperature of about 4K, for example, a radio wave equivalent to 4K is sent to the primary radiator 5 as a low-temperature calibration signal. Will be entered. The received signal is sent to the ground by the same processing as that at the time of observation. At the time of high-temperature calibration, the reflecting mirror drive mechanism 15a controls the mirror surface direction of the reflecting mirror 14a to be the position of the reflecting mirror 14a 'that is parallel to the beam direction of the primary radiation. Thus, the mesh type reflecting mirror 16 is set in a direction parallel to the beam direction of the primary radiator 5, and the mirror surface direction of the reflecting mirror 14 b is perpendicular to the beam direction of the primary radiator 5 and is positioned at 14 b ′. In this case, only the reflecting mirror 14b exists in the field of view of the primary radiator 5, and a noise temperature corresponding to the physical temperature of the reflecting mirror 14b is input. The reflecting mirror 14b is outside the heat insulating container and is controlled to a physical temperature of about 300K by a heater or the like, so that a radio wave corresponding to 300K is input to the primary radiator 5 as a high-temperature calibration signal. The high-temperature calibration signal input to the primary radiator 5 is sent to the ground by the same processing as at the time of observation. Furthermore, at the time of high temperature calibration, the mirror surface direction of the reflecting mirror 14a is controlled by the reflecting mirror driving mechanism 15a to a position where the reflecting mirror 14a 'is parallel to the beam direction of the primary radiation, and the mesh reflecting mirror driving mechanism 17 is used to control the mesh type reflection. The mirror 16 is controlled to the position of the mesh reflector 16 ′ that is orthogonal to the beam direction of the primary radiator 5, and the mirror surface direction of the reflector 14 a is perpendicular to the beam direction of the primary radiator 5 and is orthogonal to 14 b. Therefore, the reflecting mirror 14b 'and the mesh reflecting mirror 16' exist in the field of view of the primary radiator 5, and the noise temperature corresponding to the physical temperature is input. The reflecting mirror 14b is outside the heat insulating container 10 and is controlled by a heater or the like to a physical temperature of about 300K. In addition, the physical temperature of the mesh reflecting mirror 16 'is added, and the physical temperature of the mesh reflecting mirror is the total temperature. For example, by setting it to be 200K, a noise radio wave corresponding to 200K can be input to the primary radiator 5 as a high-temperature calibration signal. Therefore, it is possible to set two types of temperatures of the high-temperature calibration source. The high-temperature calibration signal input to the primary radiator 5 is sent to the ground by the same processing as at the time of observation.
[0019]
Embodiment 4 FIG.
FIG. 7 is a diagram showing a fourth embodiment of the present invention. In the figure, 14 is a reflecting mirror, 15 is a reflecting mirror drive mechanism, 18 is an RF switch, 19 is a non-reflective terminator, and 20 is an RF switch controller.
[0020]
Next, the operation will be described with reference to FIG. At the time of observation, the reflecting mirror drive mechanism 15 controls the reflecting mirror 14 to be set at a position of the reflecting mirror 14 ′ parallel to the beam direction of the primary radiator 5, and the primary radiator 5 is controlled by the RF switch controller 20. Is controlled so as to be input to the receiver 6. Therefore, the noise radio wave radiated from the surface of the earth 12 is reflected and collected by the observation reflecting mirror 2 and guided to the primary radiator 5. The noise radio wave guided to the primary radiator 5 is input into the cooled receiver 6 placed in the heat insulating container 10, amplified, detected, integrated, and then A / D converted and edited by the signal processor 7. Thereafter, it is sent to the ground as an observation signal by a transmitter (not shown). Next, at the time of low temperature calibration, the RF switch 18 is switched and controlled by the RF switch controller 20 so that the receiver 6 is connected to the non-reflection terminator 19 side. The receiver 6 receives a noise radio wave corresponding to the physical temperature of the non-reflective terminator 19, and the temperature cooled by the refrigerator 9 is set in the heat insulating container 10 so as to be a very low temperature of about 4K, for example. By controlling the temperature of the housed non-reflective terminator 19, a noise radio wave equivalent to 4K is input to the primary radiator 5 as a low-temperature calibration signal. The received signal is sent to the ground by the same processing as that at the time of observation. At the time of high-temperature calibration, the RF switch controller 20 is used to switch the receiver 6 to be connected to the primary radiator 5 in the same way as during observation, and the mirror surface of the reflector 14 is mirrored by the reflector driving mechanism 15. The direction is controlled to be set at a position orthogonal to the beam direction of the primary radiation. For this reason, a noise temperature corresponding to the physical temperature of the reflecting mirror 14 is input to the primary radiator 5. The reflector 14 is outside the heat insulating container 10 and is temperature-controlled to a physical temperature of about 300 K using a heater or the like, so that a radio wave corresponding to the physical temperature 300 K is input to the primary radiator 5 as a high-temperature calibration signal. . The high-temperature calibration signal input to the primary radiator 5 is sent to the ground by the same processing as at the time of observation.
[0021]
Embodiment 5 FIG.
FIG. 8 is a diagram showing a fifth embodiment of the present invention. In the figure, 14 is a reflecting mirror, 15 is a reflecting mirror drive mechanism, 16 is an RF switch, 20 is an RF switch controller, 21 is a horn, and 22 is a radio wave absorber.
[0022]
Next, the operation will be described with reference to FIG. At the time of observation, the reflecting mirror drive mechanism 15 controls the reflecting mirror 14 to be set at the position of the reflecting mirror 14 ′ parallel to the beam direction of the primary radiator 5 and also uses the RF switch controller 20 to perform primary radiation. The RF switch 16 is controlled so that the signal from the device 5 is input to the receiver 6. Noise radio waves radiated from the surface of the earth 12 are reflected and collected by the observation reflecting mirror 2 and guided to the primary radiator 5. The noise radio wave guided to the primary radiator 5 is input to the receiver 6, amplified, detected and integrated, then A / D converted and edited by the signal processor 7, and then observed by a transmitter (not shown). It is sent to the ground as a signal. Next, at the time of low-temperature calibration, the RF switch controller 20 switches and controls the RF switch 16 so that the receiver 6 is connected to and inputs the signal from the horn 21 to the receiver 6. By placing the radio wave absorber 22 cooled by the refrigerator 9 on the front surface of the horn 21, the horn 21 receives noise radio waves corresponding to the physical temperature of the radio wave absorber 22, and receives the receiver via the RF switch 16. 6 Here, by controlling the temperature of the non-reflection terminator housed in the heat insulating container 10 so that the cooling temperature of the radio wave absorber 22 is extremely low, for example, about 4K, The low-temperature calibration signal is input to the receiver 6 through the RF switch 16. The received signal is sent to the ground by the same processing as that at the time of observation. At the time of high temperature calibration, the RF switch controller 20 is used to switch the receiver 6 to be connected to the primary radiator 5 in the same way as during observation, and the mirror surface of the reflecting mirror 14 is controlled by the reflecting mirror driving mechanism 15. The direction is controlled to be set at a position orthogonal to the beam direction of the primary radiation. For this reason, the noise temperature corresponding to the physical temperature of the reflecting mirror 14 is input to the primary radiator 5. The reflector 14 is outside the heat insulating container 10 and is temperature-controlled to a physical temperature of about 300 K using a heater or the like, so that a radio wave corresponding to the physical temperature 300 K is input to the primary radiator 5 as a high-temperature calibration signal. . The high-temperature calibration signal input to the primary radiator 5 is sent to the ground by the same processing as at the time of observation.
[0023]
【The invention's effect】
According to the first invention, the reflecting mirror for observation that reflects radio waves from the ground, the primary radiator, the reflecting mirror disposed in front of the primary radiator, the reflecting mirror parallel to the beam direction of the primary radiator, and Drive mechanism for setting two states in orthogonal directions, receiver, primary radiator, reflector and refrigerator for cooling receiver, primary radiator, reflector and receiver cut off from outside By providing a heat insulating container, a high temperature calibration source, and a signal processor, low temperature calibration noise generated by cooling the refrigerator can be input without using a low temperature calibration reflector. There is an effect that it is possible to carry out observations that are not limited by the observation width associated with the interposition of the. In addition, since a stable low-temperature calibration source can be secured by cooling the cooler, there is an effect that calibration accuracy can be improved. Furthermore, the calibration timing can be set regardless of the scanning cycle, and there is an effect that data can be acquired at the optimal calibration timing.
[0024]
According to the second invention, the observation reflector that reflects radio waves from the ground, the primary radiator, the first reflector disposed between the observation reflector and the primary radiator, and the second radiator Reflector, reflector driving mechanism for setting two states parallel and orthogonal to the beam direction of primary radiator, receiver, refrigerator for cooling primary radiator, reflector and receiver And a heat-insulating container for thermally isolating the primary radiator, reflector and receiver from the outside, and a signal processor, without using a high-temperature calibration source, a low-temperature calibration reflector and a rotating mechanism. Low-temperature calibration noise and high-temperature calibration noise can be input, and observations that are not subject to the observation width restrictions associated with the arrangement of the high-temperature calibration source and reflector for low-temperature calibration can be performed. There is an effect that can be configured. In addition, since a stable low-temperature calibration source can be secured by cooling the cooler, there is an effect that calibration accuracy can be improved. Furthermore, the calibration timing can be set regardless of the scanning cycle, and there is an effect that data can be acquired at the optimal calibration timing.
[0025]
Further, according to the third invention, the observation reflecting mirror that reflects radio waves from the ground, the primary radiator, the first reflecting mirror disposed between the observation reflecting mirror and the primary radiator, and the second Reflector, mesh-type reflector, reflector drive mechanism for setting the reflector and mesh-type reflector in two states parallel to and orthogonal to the beam direction of the primary radiator, and mesh-type reflector A drive mechanism; a receiver; a refrigerator for cooling the primary radiator and reflector and the receiver; a heat insulating container for thermally isolating the primary radiator, reflector and receiver from the outside; and a signal By including a processor, it is possible to calibrate intermediate temperatures in addition to low-temperature calibration noise and high-temperature calibration noise without using a high-temperature calibration source, low-temperature calibration reflector and rotating mechanism, and improve calibration accuracy. As well as high temperature calibration sources and low temperature schools Constraints receiving no observation of the observation width due to the arrangement setting of use reflector there is an effect that can be configured simple radiometer can be performed. Furthermore, the calibration timing can be set regardless of the scanning cycle, and there is an effect that data can be acquired at the optimal calibration timing.
[0026]
According to the fourth aspect of the invention, the observation reflector for reflecting radio waves from the ground, the primary radiator, the reflector disposed between the observation reflector and the primary radiator, and the beam of the primary radiator Reflector driving mechanism for setting two states parallel and orthogonal to the direction, non-reflective terminator, RF switch, receiver, primary radiator, reflective mirror, non-reflective terminator and RF switch, A refrigerator for cooling the receiver, a primary radiator, a reflecting mirror, a non-reflective terminator, an RF switch, a heat insulating container for thermally blocking and storing the receiver from the outside, and a signal processor. This makes it possible to input low-temperature calibration noise and high-temperature calibration noise without using a high-temperature calibration source, a low-temperature calibration reflector, and a rotating mechanism. Simple release with no rotation mechanism There is an effect that can be configured in total. In addition, a stable low-temperature calibration source can be secured by using a cooler, and the calibration accuracy can be improved.
[0027]
According to the fifth aspect of the invention, the observation reflector that reflects radio waves from the ground, the primary radiator, the reflector disposed between the observation reflector and the primary radiator, and the beam of the primary radiator Reflector driving mechanism, radio wave absorber, RF switch, RF switch driving mechanism, receiver, primary radiator, reflecting mirror, and RF for setting the two states parallel and orthogonal to the direction A refrigerator for cooling the switch and the receiver, a primary radiator, a reflecting mirror, a radio wave absorber, an RF switch and a heat insulating container for thermally shutting out and storing the receiver from the outside, and a signal processor This makes it possible to input low-temperature calibration noise and high-temperature calibration noise without using a high-temperature calibration source, a low-temperature calibration reflector, and a rotating mechanism. Rotation mechanism without any restrictions There is an effect that can be configured have a simple radiometer. Further, there is an effect that a stable low-temperature calibration source can be secured by using a refrigerator and the calibration accuracy can be improved.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration example of a radiometer showing Embodiment 1 of the present invention.
FIG. 2 is a diagram showing an observation time of a radiometer showing Embodiment 1 of the present invention.
FIG. 3 is a diagram showing a low-temperature calibration of the radiometer showing Embodiment 1 of the present invention.
FIG. 4 is a diagram showing a high temperature calibration of the radiometer showing Embodiment 1 of the present invention.
FIG. 5 is a diagram showing a configuration example of a radiometer showing Embodiment 2 of the present invention.
FIG. 6 is a diagram showing a configuration example of a radiometer showing Embodiment 3 of the present invention.
FIG. 7 is a diagram showing a configuration example of a radiometer showing Embodiment 4 of the present invention.
FIG. 8 is a diagram showing a configuration example of a radiometer showing Embodiment 5 of the present invention.
FIG. 9 is a diagram showing a configuration example of a conventional radiometer.
FIG. 10 is a diagram showing the time of observation of a conventional radiometer.
FIG. 11 is a diagram showing a conventional radiometer at a low temperature configuration.
FIG. 12 is a diagram showing a high-temperature configuration of a conventional radiometer.
FIG. 13 is a diagram showing observation timing of a conventional radiometer.
[Explanation of symbols]
1 Radiometer, 2 Reflecting mirror for observation, 3 Reflecting mirror for low temperature calibration, 4 High temperature calibration source, 5 Primary radiator, 6 Receiver, 7 Signal processor, 8 Rotating mechanism, 9 Refrigerator, 10 Thermal insulation container, 11 Rotating Part, 12 earth, 13 deep space, 14 reflector, 15 reflector drive mechanism, 16 mesh reflector, 17 mesh reflector drive mechanism, 18 RF switch, 19 non-reflective terminator, 20 RF switch controller, 21 Horn, 22 radio wave absorber.

Claims

A radiometer that is mounted on a flying object such as an artificial satellite or an aircraft, receives weak noise radio waves naturally radiated from the earth's surface or the atmosphere, and measures the brightness temperature proportional to the received noise radio waves. An observation reflector to be used, a receiver for amplifying, detecting and integrating the received signal to obtain an output proportional to the noise radio wave input from the observation reflector, and A / D conversion and editing of the receiver output. A signal processor for generating a high temperature calibration signal for obtaining a correlation between the receiver output and luminance temperature, a primary radiator connected to the receiver, and a low temperature calibration signal for obtaining the low temperature calibration signal. A reflecting mirror movable in a direction orthogonal to and parallel to the beam direction of the primary radiator, a reflecting mirror driving mechanism for changing and controlling the direction of the reflecting mirror, the receiver, the reflecting mirror, and the primary A refrigerator that cools the projector, the receiver, the reflecting mirror, and the primary radiator and a heat insulating container for thermally shielding and insulating from the outside, and the signal for switching the reception signal of the primary radiator A radiometer comprising a rotation mechanism for rotating other than the high-temperature calibration source.

A radiometer that is mounted on a flying object such as an artificial satellite or an aircraft, receives weak noise radio waves naturally radiated from the earth's surface or the atmosphere, and measures the brightness temperature proportional to the received noise radio waves. An observation reflector to be used, a receiver for amplifying, detecting and integrating the received signal to obtain an output proportional to the noise radio wave input from the observation reflector, and A / D conversion and editing of the receiver output. A signal processor for generating a high-temperature calibration signal to obtain a correlation between the receiver output and luminance temperature, a primary radiator connected to the receiver, and a primary radiator A second reflecting mirror disposed on the front surface for obtaining a low-temperature calibration signal; a reflecting mirror driving mechanism for variably controlling the directions of the first and second reflecting mirrors; the receiver; the second reflecting mirror; Cool the reflector and the primary radiator. A refrigerator for said receiver, said second reflecting mirror, and the radiometer to the outside by housing the primary radiator, characterized by comprising a heat-insulating container for shielding heat insulating thermally.

A radiometer that is mounted on a flying object such as an artificial satellite or an aircraft, receives weak noise radio waves naturally radiated from the earth's surface or the atmosphere, and measures the brightness temperature proportional to the received noise radio waves. An observation reflector to be used, a receiver for amplifying, detecting and integrating the received signal to obtain an output proportional to the noise radio wave input from the observation reflector, and A / D conversion and editing of the receiver output. A signal processor for generating, a first reflecting mirror for generating a first high-temperature calibration signal to obtain a correlation between the receiver output and luminance temperature, and a mesh-type reflecting mirror for generating a second high-temperature calibration signal A second reflector for obtaining a low-temperature calibration signal, a primary radiator connected to the receiver, and a reflector driving mechanism for changing and controlling the directions of the first and second reflectors , Direction of the mesh reflector A mesh-type reflector driving mechanism for changing and controlling, the receiver, the second reflector, the refrigerator for cooling the mesh-type reflector and the primary radiator, the receiver, the second A radiometer comprising: a reflecting mirror, a mesh-type reflecting mirror and the primary radiator, and a heat insulating container for thermally shielding and insulating from the outside.

A radiometer that is mounted on a flying object such as an artificial satellite or an aircraft, receives weak noise radio waves naturally radiated from the earth's surface or the atmosphere, and measures the brightness temperature proportional to the received noise radio waves. An observation reflector to be used, a receiver for amplifying, detecting and integrating the received signal to obtain an output proportional to the noise radio wave input from the observation reflector, and A / D conversion and editing of the receiver output. A signal processor, a reflector for generating a high-temperature calibration signal for obtaining a correlation between the receiver output and the luminance temperature, a reflector driving mechanism for changing and controlling the direction of the reflector, A primary radiator connected to a receiver; an RF switch for switching signals interposed between the primary radiator and the receiver; an RF switch controller for controlling the RF switch; and the R A non-reflective terminator connected to a switch; a refrigerator that cools the receiver, the reflective mirror, the primary radiator, and the non-reflective terminator; the receiver, the reflective mirror, the primary radiator, and the non-reflective A radiometer comprising a heat insulating container for accommodating a reflection terminator and thermally shielding and insulating from the outside.

A radiometer that is mounted on a flying object such as an artificial satellite or an aircraft, receives weak noise radio waves naturally radiated from the earth's surface or the atmosphere, and measures the brightness temperature proportional to the received noise radio waves. An observation reflector to be used, a receiver for amplifying, detecting and integrating the received signal to obtain an output proportional to the noise radio wave input from the observation reflector, and A / D conversion and editing of the receiver output. A signal processor, a reflector for generating a high-temperature calibration signal for obtaining a correlation between the receiver output and the luminance temperature, a reflector driving mechanism for changing and controlling the direction of the reflector, A primary radiator connected to a receiver; an RF switch for switching signals interposed between the primary radiator and the receiver; an RF switch controller for controlling the RF switch; A horn connected to an RF switch; a radio wave absorber disposed in front of the horn; the receiver, the reflecting mirror, the primary radiator, a refrigerator that cools the radio wave absorber, the receiver, and the reflection A radiometer comprising a mirror, the primary radiator, and the heat absorbing container for accommodating the electromagnetic wave absorber and thermally shielding and insulating from the outside.