JP4297400B2

JP4297400B2 - Intermittent satellite signal positioning system

Info

Publication number: JP4297400B2
Application number: JP2000064475A
Authority: JP
Inventors: 勝男由井
Original assignee: Japan Radio Co Ltd
Current assignee: Japan Radio Co Ltd
Priority date: 2000-03-09
Filing date: 2000-03-09
Publication date: 2009-07-15
Anticipated expiration: 2020-03-09
Also published as: JP2001255363A

Description

【０００１】
【発明の属する技術分野】
本発明は、地すべり地帯の監視等、衛星信号搬送波を用いて高精度の測位位置を定期的に得る、間欠衛星信号測位システムに関する。
【０００２】
【従来の技術】
衛星信号搬送波を用いて高精度の測位位置を求める場合には、親局、子局とも同じタイミングでデータ収集する必要がある。一般的に、親局、子局間は距離が離れているため、伝送しあってタイミング同期を行うのは困難である。したがって、親局、子局とも、各局に設置されている衛星信号受信機において、追尾した衛星信号から衛星システムの時刻系における各局の現在時刻を求め、それを利用して同じタイミングでデータ収集しているのが一般的である。
【０００３】
また、高精度測位位置を求めるのに別の演算装置を用いると、リアルタイム性に劣る、データ転送量が極めて多い等の欠点があるため、最近では、どちらかの局のデータを他方の局に送信して、両局のデータを用いて測位位置を求めることが多い。
【０００４】
また、特に移動体においては、測位位置計算に不可欠な整数値バイアス（衛星信号搬送波の整数サイクル分の不確定値）を求めるため、衛星信号受信機を連続動作させているのが一般的である。しかし、地すべり地帯の監視等、移動速度が極めて遅い場合には省エネルギー化のため、子局側を間欠測位させるシステムも最近提案され、その場合に、子局側の再追尾を早くするため、親局から子局に衛星選択情報や、詳細衛星軌道情報を送る工夫がなされている。そのためには、親局側は詳細衛星軌道情報、並びに衛星選択情報の決定に必要な概略衛星軌道情報を収集する必要があるため、従来システムにおいては、親局側の衛星信号受信機を連続動作させている。
【０００５】
【発明が解決しようとする課題】
前記したように、従来の間欠測位させる衛星信号測位システムにおいては、親局側は連続受信する必要があったため、親局側の省エネルギー化が計れない欠点があった。また、子局側を間欠測位させる場合、親局からの起動待ちを行う場合が多いが、子局通信装置は親局からの起動信号監視のために常時待ち受け状態にしておく必要があり、通信装置部分での省エネルギー化が計れない欠点があった。
【０００６】
このため、本発明は、親局側、子局側の衛星信号受信機を共に間欠測位させ、且つ、親局、子局間通信装置を測位位置が得られる状態のときのみ稼働させることで、省エネルギー化を実現した衛星信号測位システムを提供することを目的とする。
【０００７】
【課題を解決するための手段】
請求項１の間欠衛星信号測位システムは、親局側と少なくとも１つの子局側との間で衛星搬送波位相を用いて高精度に測位する間欠衛星信号測位システムであって、親局側は、衛星信号からの基準時刻に基づいてそれぞれ間欠動作される親局側衛星信号受信機及び親局側通信装置を備え、前記親局側衛星信号受信機は、間欠動作中に衛星信号から同一基準時刻の全衛星の概略衛星軌道情報を順次取得し、この概略衛星軌道情報に基づいて受信すべき衛星情報を作成し記憶し、同じく間欠動作中に衛星信号から各衛星の詳細衛星軌道情報の更新をその軌道情報に含まれる基準時刻によって監視し、更新されたときのみ間欠動作を一時的に変更して更新された詳細軌道情報を取得し記憶し、記憶されている受信すべき衛星情報、更新された詳細軌道情報を測位に利用し、前記親局側通信装置は、その間欠動作時に、前記受信すべき衛星情報及び更新された詳細軌道情報を子局側に送信し、子局側は、衛星信号からの基準時刻に基づいてそれぞれ間欠動作される子局側衛星信号受信機及び子局側通信装置を備え、前記子局側通信装置は、その間欠動作時に、親局側から送信された受信すべき衛星情報及び更新された詳細軌道情報を受信し記憶し、前記子局側衛星信号受信機は、間欠動作時に、記憶されている受信すべき衛星情報、更新された詳細軌道情報を測位に利用することを特徴とする。
【０００８】
請求項２の間欠衛星信号測位システムは、請求項１の間欠衛星信号測位システムにおいて、親局側通信装置の間欠動作のタイミングを、親局側衛星信号受信機の間欠動作のタイミングと異ならせると共に、子局側通信装置の間欠動作のタイミングを、子局側衛星信号受信機の間欠動作のタイミングと異ならせることを特徴とする。
【０００９】
請求項３の間欠衛星信号測位システムは、親局側の衛星信号を受信し、現在時刻と、衛星信号受信機での搬送波位相等の追尾データを測定する衛星信号受信測位装置と、前記衛星信号受信測位装置からのデータから概略衛星軌道情報（アルマナックデータ）を求め記憶するアルマナック記憶装置と、前記アルマナック記憶装置で記憶した概略衛星軌道情報、及び衛星信号受信測位装置から得られる現在時刻と、既知である親局位置情報から受信すべき衛星情報を記憶する衛星選択記憶装置と、前記衛星信号受信測位装置からのデータから詳細衛星軌道情報（エフエメリスデータ）を求め記憶すると共に、その一部及び全てを出力するエフエメリス収集記憶装置と、前記衛星信号受信機での搬送波位相等の追尾データと、親局位置情報と、前記衛星選択記憶装置からの受信すべき衛星情報と、エフエメリス収集記憶装置からの詳細衛星軌道情報を少なくとも１つの子局に送出すると共に、各子局から送られてきた測位位置データを受信し、衛星信号受信測位装置に出力する親局側通信装置と、前記測位位置データを衛星信号受信測位装置経由で記憶する子局位置記憶装置と、前記衛星信号受信測位装置から得られる現在時刻を元に、間欠動作用の電源オン／オフ装置の動作タイミングを調整するタイミング装置と、前記タイミング装置で調整され、前記衛星信号受信測位装置と、前記親局側通信装置を別々のタイミングでオン／オフ制御する、電源オン／オフ装置と、で構成される親局側装置と、親局側から送られてくる親局の搬送波位相等の追尾データと親局位置情報と、受信すべき衛星情報と、詳細衛星軌道情報を受信し、各々を衛星信号受信測位装置、衛星選択記憶装置、エフエメリス記憶装置に出力すると共に、衛星信号受信測位装置からの測位位置データを親局側へ送出する子局側通信装置と、親局から送られてきた受信すべき衛星情報を記憶すると共に、その受信すべき衛星情報を衛星信号受信測位装置に出力する衛星選択記憶装置と、親局から送られてきた各衛星の詳細衛星軌道情報を記憶すると共に、記憶している全ての衛星の詳細衛星軌道情報を衛星信号受信測位装置に出力するエフエメリス記憶装置と、前記受信すべき衛星情報を元に子局側の衛星信号を受信し、現在時刻と、搬送波位相等の追尾データを測定し、そのデータと親局での搬送波位相等の迫尾データと、エフェメリス記憶装置からの詳細衛星軌道情報と、親局位置情報を用いて測位位置を求める衛星信号受信測位装置と、前記衛星信号受信測位装置から得られる現在時刻を元に、間欠動作用の電源オン／オフ装置の動作タイミングを調整するタイミング装置と、前記タイミング装置で調整され、前記衛星信号受信測位装置と前記子局側通信装置を別々のタイミングでオン／オフ制御する、電源オン／オフ装置と、で構成される少なくとも１つの子局側装置、から構成されることを特徴とする。
【００１０】
請求項４の間欠衛星信号測位システムは、請求項３の間欠衛星信号測位システムにおいて、親局から搬送波位相等の追尾データと親局位置情報を送る代わりに、親局側で求めた搬送波位相等の追尾データを補正した補正済み追尾データを送ることを特徴とする。
【００１１】
請求項５の間欠衛星信号測位システムは、請求項３の間欠衛星信号測位システムにおいて、親局から搬送波位相等の追尾データを送り、子局側で測位位置を求める代わりに、子局から搬送波位相等の追尾データを送り、親局側で各子局の測位位置を求めることを特徴とする。
【００１２】
請求項６の間欠衛星信号測位システムは、請求項３〜５の間欠衛星信号測位システムにおいて、データ監視局との間でデータを送受するデータ監視局用通信装置を備え、データ監視局から位置情報を要求された時、間欠動作中であっても電源オン／オフ装置を制御して衛星信号受信測位装置の電源をオンにし、親局側の子局位置記憶装置に記憶した子局位置情報を衛星信号受信測位装置経由で読み込み、それをデータ監視局に送ることを特徴とする。
【００１３】
本発明によれば、親局側も、子局側と同様に、極めて動作電流が少ない電源オン／オフ装置により間欠動作とすることができるため、親局側も省エネルギー化が計ることが出来る。
【００１４】
また、子局側通信装置での親局からの起動待ちを行なわず、子局側通信装置も衛星システム時刻に同期した間欠動作が可能なため、通信装置部分での省エネルギー化が計れる。
【００１５】
また、親局、子局間の通信装置も、本当に測位位置を求める間のみ動作し、衛星信号受信機をオンにしてから、衛星信号受信機が安定するまでの間も電源断にさせることができる。このことにより、さらに通信装置部分での省エネルギー化が計れる。
【００１６】
【発明の実施の形態】
以下、図面を参照して、本発明の実施の形態について説明する。図１は本発明の間欠衛星信号測位システムのシステム構成を示す図であり、図２は衛星軌道情報の収集方法を説明する図である。
【００１７】
図１において、親局側は、アンテナ１０Ｂから衛星信号を受ける衛星信号受信機５０Ｂと、子局側との間でデータの送受信を行う親局側通信装置３Ｂと、アンテナ３０を介してデータ監視局とのデータの送受信を行うデータ監視局間通信装置９と、時刻情報を受けて電源オフ指令を出力するタイミング調整装置４Ｂと、電源オフ指令を受けて衛星信号受信機５０Ｂ等に電源オン／オフ指令信号を与える電源オン／オフ装置１Ｂとから構成される。
【００１８】
さらに、衛星信号受信機５０Ｂは、衛星信号受信測位装置２Ｂと、全衛星の概略衛星軌道情報（アルマナックデータ）を取得して記憶するアルマナック記憶装置７と、全衛星の概略衛星軌道情報等に基づいて選択する衛星を記憶し受信すべき衛星情報を出力する衛星選択記憶装置６Ｂと、各衛星の詳細衛星軌道情報（エフェメリスデータ）を取得して記憶するエフェメリス収集記憶装置５Ｂと、子局側から送信された子局の位置データを記憶する子局位置記憶装置８とから構成される。
【００１９】
子局側は、アンテナ１０Ａから衛星信号を受ける衛星信号受信機５０Ａと、親局側との間でデータの送受信を行う子局側通信装置３Ａと、時刻情報を受けて電源オフ指令を出力するタイミング調整装置４Ａと、電源オフ指令を受けて衛星信号受信機５０Ａ等に電源オン／オフ指令信号を与える電源オン／オフ装置１Ａとから構成される。子局側は、１つに限らず複数の子局に対しても同様に構成される。
【００２０】
さらに、衛星信号受信機５０Ａは、衛星信号受信測位装置２Ａと、親局側から送信された受信すべき衛星情報を出力する衛星選択記憶装置６Ａと、親局側から送信された各衛星の詳細衛星軌道情報（エフェメリスデータ）を記憶するエフェメリス記憶装置５Ａとから構成される。
【００２１】
次に、親局側の各装置の構成、動作について説明する。
【００２２】
衛星信号受信測位装置２Ｂは、間欠動作信号Ｐ５を受けて稼働開始時に、受信すべき衛星情報を衛星選択記憶装置６Ｂから読み出し、その衛星信号の受信を行う。そして、親局側にて衛星信号アンテナ１０Ｂからの衛星信号を受信し、その受信データから現在時刻Ｔ２をまず求める。現在時刻Ｔ２が求まった時点から、ある決まったタイミング（例えば正秒時）に、衛星信号受信機での搬送波位相等の追尾データＢ１を測定する。
【００２３】
アルマナック記憶装置７は、衛星信号受信測位装置２Ｂが間欠稼働している間、各衛星からのデータから概略衛星軌道情報（アルマナックデータ）とその情報の基準時刻に関する部分を切り出し、別々の稼働時間帯に収集したデータの内、同じ基準時刻のデータをまとめて記憶する。
【００２４】
このように、すべての衛星の概略衛星軌道情報が、間欠稼働中に収集され記憶されるから、その情報が必要なときにはいつでも利用することが出来る。
【００２５】
衛星選択記憶装置６Ｂは、アルマナック記憶装置７で記憶している概略衛星軌道情報、及び衛星信号受信測位装置２Ｂから得られる現在時刻Ｔ２と、明示しない入力装置から入力される既知の親局位置情報から、親局において現在受信できる可視衛星情報を求め、それを記憶する。そして、受信すべき衛星情報Ｓ１を衛星信号受信測位装置２Ｂ及び親局側通信装置３Ｂに出力する。衛星情報には可視衛星番号と、各局の移動速度、受信機内部発振器寄与分を加味しない各衛星のドップラー周波数予測値が含まれている。受信機内部発振器寄与分は、衛星信号受信測位装置２Ｂ稼働時に追尾した衛星信号データから求められるので、それをドップラー周波数予測値に加味し、それを衛星信号受信測位装置２Ｂ用として用いても良い。
【００２６】
エフエメリス収集記憶装置５Ｂは、衛星信号受信測位装置２Ｂが稼働している間、各衛星からのデータから詳細衛星軌道情報（エフェメリスデータ）とその情報の基準時刻に関する部分を切り出し、記憶している基準時刻と一致しているか、また新しい衛星のデータであるか否かをチェックする。記憶している基準時刻と一致しているとき、それまでの衛星のデータであるときは記憶している詳細衛星軌道情報をそのまま利用する。一方、基準時刻が更新された場合、及び新しい衛星のデータの場合のみ、電源オン／オフ装置に指示して、新しい基準時刻の詳細衛星軌道情報を全て収集するまで、間欠動作を変更し、稼働時間を一時的に延長する。また、その際詳細衛星軌道情報が新しくなった衛星の番号も記憶し、その衛星の詳細衛星軌道情報を、親局側通信装置が稼働している間に、順次子局側へ送信する。
【００２７】
このように、間欠稼働中に、各衛星の詳細衛星軌道情報がそれまでの基準時刻のものと変化が無いことを確認し、基準時刻に変化があったときには間欠動作を変更し、稼働時間を一時的に延長して、新しい詳細衛星軌道情報が収集され記憶されると共に、子局側にも送信されるから、間欠動作をしつつ、常に最新の詳細衛星軌道情報を利用することが出来る。
【００２８】
親局側通信装置３Ｂは、間欠動作信号Ｐ４を受けて動作し、衛星信号受信機２Ｂでの搬送波位相等の追尾データＢ１と、図示しない入力装置から入力された既知の親局位置情報と、衛星選択記憶装置６Ｂからの受信すべき衛星情報Ｓ１と、エフエメリス収集記憶装置５Ｂに記憶されている詳細衛星軌道情報Ｅ２を少なくとも１つの子局に送出すると共に、各子局から送られてきた測位位置データＦ１を受信し、衛星信号受信測位装置２Ｂに出力する。
【００２９】
子局位置記憶装置８は、各子局から送られてきた測位位置データＦ１を記憶し、データ監視局間通信装置９から要求された時、衛星信号受信機２Ｂ経由にて、その測位位置データＦ１を出力する。
【００３０】
電源オン／オフ装置１Ｂでは、タイミング調整装置からの電源断指令により、各装置（衛星信号受信測位装置２Ｂまたは親局側通信装置３Ｂ用）の電源を断にすると共に、カウンター動作を開始し、タイミング調整装置４Ｂから指示された電源断時間に相当する分カウンター動作をした後に各装置の電源をオンにする。なお、電源断時間帯であっても、データ監視局間通信装置９や、前述したエフエメリス収集記憶装置５Ｂから要求されている間は一時的に衛星信号受信測位装置２Ｂの電源をオンにする。この電源オン／オフ装置１Ｂは基本的には低精度の発振器、カウンター回路、電源オン／オフリレー回路のみで構成されるので、消費電流を通信装置の待ち受け状態時に比べ、その数１０分の１にすることができ、エネルギー消費量を極めて少なくできる。
【００３１】
タイミング調整装置４Ｂは、衛星信号受信測位装置２Ｂから得られる現在時刻を元にして、各装置（衛星信号受信測位装置２Ｂまたは親局側通信装置３Ｂ用）を希望する間欠間隔に調整する。具体的には、各装置の稼働を停止する前に、現在時刻ＴＡと電源オン希望時刻ＴＢの差ＴＣを電源オン／オフ装置１Ｂに出力した後、電源断指令を電源オン／オフ装置１Ｂに出力する。このタイミング調整は、衛星信号受信測位装置２Ｂ用と、親局側通信装置３Ｂ用の２種類について独立に実施する。
【００３２】
なお、実際には、アルマナック記憶装置７、衛星選択記憶装置６Ｂ、エフエメリス収集記憶装置５Ｂ、子局位置記憶装置８は、衛星信号受信測位装置２Ｂと共に、衛星信号受信機５０Ｂを構成しているが、電源断時もバックアップ電池により内容が保持されるバックアップＲＡＭを用いる。したがって、衛星信号受信測位装置２Ｂは稼働時にその内容を常時参照することができる。しかしながら、逆に入出力部を持たないため、子局位置記憶装置８に記憶されている内容を読み出すためには、衛星信号受信潮位装置２Ｂを稼働させ、衛星信号受信測位装置２Ｂ経由にて読み出すことになる。
【００３３】
データ監視局間通信装置９は、遠方のデータ監視局から位置情報を要求された時、子局位置記憶装置８に記憶されている最新の子局位置情報を、衛星信号受信測位装置２Ｂ経由にて読み出し、データ監視局に送出する。このデータ監視局からの要求は不定期であるため、データ送出後は待ち受け状態となる。そして、子局位置記憶装置８に記憶されている内容を読み出すためには、衛星信号受信測位装置２Ｂを稼働させる必要がある。
【００３４】
このため、データ監視局用通信装置９は、遠方のデータ監視局から位置情報を要求された時には、まず要求信号Ｐ１を電源オン／オフ装置１Ｂに出力し、衛星信号受信測位装置２Ｂを稼働させる。（親局側通信装置については、稼働させる必要はないので、現在の稼働状態のままとする。）その後、衛星信号受信測位装置２Ｂに位置情報出力要求を行い、衛星信号受信測位装置２Ｂ経由にて子局位置記憶装置８に記憶されている最新の子局位置情報Ｆ１を得、データ監視局用通信装置９からデータ監視局に送信する。
【００３５】
なお、本実施の形態では、データ監視局用通信装置９をデータ送出期間以外は常時待ち受け状態とする構成にしているが、衛星信号受信測位装置２Ｂから得られる現在時刻を元に、更に待ち受け状態とする時間を限定することで、省エネルギー化を計っても良い。
【００３６】
次に、子局側の構成及び各装置の動作について説明する。
【００３７】
子局側通信装置３Ａは、親局側から送られてくる親局の搬送波位相等の追尾データＢ１と親局位置情報と、受信すべき衛星情報Ｓ１と、詳細衛星軌道情報Ｅ２を受信し、各々を衛星信号受信測位装置２Ａ、衛星選択記憶装置６Ａ、エフエメリス記憶装置５Ａに出力すると共に、衛星信号受信測位装置２Ａからの測位位置データＦ１を親局側へ送出する。
【００３８】
衛星選択記憶装置６Ａは、親局から送られてきた受信すべき衛星情報Ｓ１を記憶する。親局側からは、受信機内部発振器寄与分を加味しない、ドップラー周波数予測値が送られてくる。衛星信号受信測位装置２Ａ内の内部発振器寄与分は、衛星信号受信測位装置２Ａが稼働時に追尾した衛星信号データから求められるので、それをドップラー周波数予測値に加味しても良い。
【００３９】
エフエメリス記憶装置５Ａは、親局から送られてきた各衛星の詳細衛星軌道情報Ｅ２を記憶する。
【００４０】
衛星信号受信測位装置２Ａは、間欠動作信号Ｐ２を受けて稼働開始時には、受信すべき衛星情報Ｓ１を衛星選択記憶装置６Ａから読み出し、その衛星の受信を行う。その衛星データから、現在時刻Ｔ１をまず求める。
【００４１】
現在時刻Ｔ１が分かった時点で、親局側で搬送波位相等の追尾データＢ１を収集したのと同じタイミングで、子局側の搬送波位相等の追尾データＢ１を収集する。その子局側の搬送波位相等の追尾データＢ１と、親局での搬送波位相等の追尾データと、エフエメリス記憶装置５Ａに記憶されている各衛星の詳細衛星軌道情報Ｅ２と、親局位置情報を用いて高精度の測位位置Ｆ１を求める。なお、実際には通信装置による遅延があるため、衛星信号受信測位装置２Ａ側のデータを記憶しておき、同じタイミングの親局側からのデータを受信した時に、測位位置計算を行っている。
【００４２】
電源オン／オフ装置１Ａ，タイミング調整装置４Ａの動作は、前述した親局側に設置される電源オン／オフ装置１Ｂ，タイミング調整装置４Ｂと同様であるので、簡単のためにここでは説明を省略する。
【００４３】
以上の説明では、通常動作である間欠動作状態を説明しているが、高精度位置を求めるためには、まず整数値バイアス（衛星信号搬送波の整数サイクル分の不確定値）が必要である。
【００４４】
そのため、この間欠衛星信号測位システムを最初に動作開始した時のみ連続動作モードにして、整数値バイアスを求めている。または、子局の初期位置を別途入力する等の方法により、整数値バイアスを決定する。
【００４５】
さて、本発明では間欠動作にて、詳細衛星軌道情報（エフェメリスデータ）並びに概略衛星軌道情報（アルマナックデータ）を収集しており、親局側は連続動作を必要としていた従来のシステムとは、この点で大きく異なっている。このように親局側及び子局側とも間欠動作を行わせることにより、省エネルギーレベルを一段と高くすることが可能となっている。
【００４６】
このように親局側及び子局側とも間欠動作を行わせ、かつ測位データを得るためには、間欠動作をさせながらも、常時、最新の詳細衛星軌道情報及び並びに概略衛星軌道情報を収集しておく必要がある。その収集方法を、ＧＰＳ衛星の場合を例として説明する。
【００４７】
ＧＰＳの場合、基本メッセージは１フレーム（３０秒）単位で構成される。１フレームは、６秒単位の５つのサブフレームから構成される。この内、第１〜第３サブフレームには、衛星時計補正データや詳細衛星軌道情報がそれらの基準時刻と共に含まれており、第４、第５サブフレームには、概略衛星軌道情報や健康状態がそれらの基準時刻と共に含まれて構成されている。ただし、全衛星分の概略衛星軌道情報を得るには、連続する２５フレーム（マスターフレーム）に含まれている概略衛星軌道情報を収集する必要があり、そのためには１２．５分の時間を要する。
【００４８】
まず、概略衛星軌道情報の収集について説明する。概略衛星軌道情報は、前述のように、３０秒毎の繰り返しデータ内の、後半の１２秒分のデータ部分に、順次各衛星毎の概略衛星軌道情報とその基準時刻を含ませる構成となっているから、１２．５分間（０．５分＊２５フレーム）連続受信すれば、その基準時刻における全衛星の概略衛星軌道情報が得られる。ただし、１２．５分周期でその内容が更新される訳ではなく、１日程度の周期で更新され、更新した時は基準時刻も更新される。
【００４９】
本発明では、内容更新周期が１日と長く、１２．５分毎繰り返されることを利用し、間欠周期を１２．５分より短く、かつ概略衛星軌道情報周期と非同期になるように設定することで、１２．５分より長い時間が必要になるものの、全衛星の概略衛星軌道情報を得ている。
【００５０】
図２にその概念図を示す。図２における数字は、１２．５分毎繰り返される３０秒毎のフレーム番号である。斜線部分、又は塗りつぶし部分を、概略衛星軌道情報が含まれている部分とする。本システムでは衛星システムの時刻系における現在時刻を求めているので、衛星システムの時刻に同期した間欠動作が可能である。ここで、間欠周期を１分とし、間欠動作させる時間を概略衛星軌道情報が含まれている１２秒間に設定した場合を考える。この場合、斜線部分のデータは受信できないが、塗りつぶし部分のデータは受信できる。したがって、例えば最初の１２．５分・周期の間で、ＮＯ．１０フレームのデータは稼働時間帯のため受信できるが、ＮＯ．９フレームのデータは受信することはできない。しかしながら、次の１２．５分周期の部分では、ＮＯ．９フレームのデータは、図２に示すように、稼働時間帯になり、受信できる。
【００５１】
つまり、図２の例では、１２．５＊２＝２５分周期で、全衛星の概略衛星軌道情報を得ることができる。なお、図２では１フレーム飛びの間欠時間としているが、例えば２フレーム飛びの間欠時間としてもよく、１巡目では１，４，７・・・、２巡目では３，６，９・・・、３巡目では２，５，８・・・のフレームデータが受信できる。この場合には、１２．５＊３＝３７．５分周期で、全衛星の概略衛星軌道情報を得ることが出来る。
【００５２】
これらの周期はデータ更新周期１日に比べ十分短く、実用上問題はない。本発明では、このようにして、間欠動作でありながら、全衛星の概略衛星軌道情報を得ている。
【００５３】
次に、詳細衛星軌道情報について説明する。ＧＰＳの場合、概略衛星軌道情報は３０秒毎に繰り返す各衛星のデータの内、前半１８秒分に各衛星の詳細衛星軌道情報とその基準時刻を含ませる形とし、その１８秒分のデータを収集すれば、各衛星の詳細衛星軌道情報が得られるようになっている。ただし、３０秒周期でその内容が更新される訳ではなく、通常は１乃至２時間程度の周期で更新され、更新した時は基準時刻も更新される。また、１８秒分のデータは、各６秒毎の小フレーム３個に更に分割されており、その各小フレームの全てに基準時刻は含まれている。
【００５４】
本発明では、内容更新周期は１時間程度と長く、３０秒毎に繰り返され、１８秒の内の各６秒毎の小フレームに基準時刻が含まれていることを利用し、詳細衛星軌道情報を収集する頻度を極めて少なくしている。概略衛星軌道情報の場合と同様に、図２を利用してその概念を説明する。図２において、斜線部分、塗りつぶし部分を、詳細衛星軌道情報が含まれている部分のある小フレームとする。ここで、間欠周期を１分とし、間欠動作させる時間をある小フレームが含まれている６秒間に設定した場合を考える。この場合、斜線部分のデータは受信できないが、塗りつぶし部分のデータは受信できる。したがって、例えばＮＯ．９フレームにおけるデータはチェックできないが、次のＮＯ．１０フレームにおけるデータはチェックできる。
【００５５】
各小フレームには、基準時刻が含まれているから、詳細衛星軌道情報が更新されたかは、その基準時刻をチェックすれば良い。エフェメリス収集記憶装置５Ｂに記憶されている、当該衛星の詳細衛星軌道情報の基準時刻と、図２の塗りつぶし部分に含まれる詳細衛星軌道情報の基準時刻が一致するかどうかをチェックする。或いは、新しく取得した塗りつぶし部分に含まれる詳細衛星軌道情報の基準時刻が、それ以前に取得していた詳細衛星軌道情報の基準時刻と一致するかどうかをチェックする。そして、これらが一致しなかったときに、詳細衛星軌道情報が更新された訳であるから、この小フレーム及び他の小フレームの詳細衛星軌道情報を収集すれば、各衛星の新しい詳細衛星軌道情報が得られる。
【００５６】
なお、概略衛星軌道情報の取得と詳細衛星軌道情報のチェックとは、図２の斜線部及び塗りつぶし部で引き続いて行ってもよく、また別々の時間帯に実施してもよい。
【００５７】
また、新しい衛星が可視範囲に現れ、追尾に初めて成功した時にも、詳細衛星軌道情報収集を行う。新衛星が現れる頻度は短くて２０分に一回程度、各衛星の詳細衛星軌道情報の更新周期は通常１乃至２時間程度の周期であるので、詳細衛星軌道情報を収集する頻度は２０分に１回（１８秒）程度と極めて少なくできる。
【００５８】
なお、詳細衛星軌道情報を収集する場合には、一時期、間欠動作を中止することになるが、これは図１の構成図で説明したように、電源オン／オフ装置がエフェメリス収集記憶装置５Ｂからの更新情報を受けて、詳細衛星軌道情報の収集が終了するまで間欠動作を停止する。
【００５９】
なお、この間欠衛星信号測位システムでは、前記工夫により連続動作している場合と比較して、詳細衛星軌道情報の更新が遅れる。しかし、親局データについても子局データについても、親局からのエフエメリスデータを共通に使用しているから、この程度の更新の遅れは全く精度劣化には結びつかないので、問題はない。
【００６０】
以上のように、本発明では、概略及び詳細衛星軌道情報を問題なく収集しながら、親局側も間欠動作とすることができるため、親局側も省エネルギー化が計れる。
【００６１】
また、従来システムにおける子局側の間欠動作は、通信装置部分を受け持ち状態とさせる構成であったため、通信装置部分での省エネルギー化が計れなかったが、本発明では、子局側でも、電源オン／オフ装置１Ａにて、通信装置部分も衛星システム時刻に同期した間欠動作としたため、通信装置部分を大きく省エネルギー化することができる。
【００６２】
さらに、従来システムにおいて、子局側における衛星追尾時間短縮のため、子局の間欠動作開始時に、親局側から衛星選択情報と全衛星の詳細衛星軌道情報を送付するシステムがある。この従来システムの場合、親局子局間の通信装置は、衛星信号受信機稼働に先立って動作し、衛星信号受信機稼働中全て稼働してなくてはならなかった。本発明では、基本的には親局子局間の通信装置は、搬送波位相を送信するときなど、測位解が得られる状況のみ稼働させることができるため、更に通信装置部分の省エネルギー化が行える。
【００６３】
また、衛星配置変化はゆっくりであるので、１０分程度時間が異なっていても、せいぜい可視衛星が１つ異なる程度であり、その異なった衛星は仰角が低く間欠測位稼働時の短い時間内に追尾することは困難な衛星である。また、１０分時間が異なっていてもドップラー周波数の変化はわずかである。したがって、１０分以内に求めた衛星選択情報を用いれば、実質上の問題は生じない。
【００６４】
そこで、本実施の形態では、親局で現在時刻が分かった時点で求めた衛星選択情報を子局側に送るが、衛星信号受信測位装置２Ａはその情報を次回の間欠動作時に参照する形としている。したがって、この方式にすれば、親局子局間の通信装置は、衛星信号受信機稼働に先立って衛星選択情報を送る必要がなくなり、測位解が得られる状況のみ稼働させれば良くなる。
【００６５】
また、本実施例では、エフエメリス記憶装置５Ａを用いているため、各稼働時間内に親局から送出する際、全衛星の詳細衛星軌道情報を送る必要はなく、順次（例えば各稼働時間内に１衛星ずつ）送出していけば良いので、詳細衛星軌道情報を送るための通信時間も１秒以内と極めて短くできる。
【００６６】
また、前記したように、測位解を求める際、親局データ、子局データ共、親局から送られてくるエフェメリスデー夕を共通に使用するので、エフエメリス更新が遅れても精度劣化は発生しない。したがって、親局、子局間の通信装置は本当に測位位置を求める間のみ動作させればよく、衛星信号受信機をオンにしてから衛星信号受信機が安定するまでの間も、電源断にさせることができるため、通信装置部分での省エネルギー化が計れる。
【００６７】
また、本発明では、親局及び子局で常に同じエフェメリスデータを使用することが確保されているから、親局側において、子局側に送るべき親局側での搬送波位相等の追尾データに関する観測値の誤差分等の補正量を算出することが出来る。このため、他の実施形態として、親局側から搬送波位相等の追尾データと親局位置情報を送ることに代えて、親局側で求めた搬送波位相等の追尾データを補正し、補正済み追尾データを送る方式にしても良い。
【００６８】
また、測位位置を求める処理の処理負荷が重いため、複数の子局において、親局から搬送波位相等の追尾データを送り、子局側で測位位置を求める形で、処理負荷の分散を行っている。これに代えて、子局から搬送波位相等の追尾データを送り、親局側で各子局の測位位置を求める形にしても良い。この場合には、親局側の処理負荷が増えるので、各子局データが得られた時点から、親局での信号追尾を中止し、その測位計算のみを行うことにより、親局での処理時間を短縮し、省エネルギー化を計っても良い。
【００６９】
【発明の効果】
本発明では、親局側も、子局側と同様に、極めて動作電流が少ない電源オン／オフ装置により間欠動作とすることができるため、親局側も省エネルギー化が計れる効果がある。
【００７０】
また、子局側通信装置での親局からの起動待ちを行なわず、子局側通信装置も衛星システム時刻に同期した間欠動作が可能なため、通信装置部分での省エネルギー化が計れる効果がある。
【００７１】
また、親局、子局間の通信装置も、本当に測位位置を求める間のみ動作し、衛星信号受信機をオンにしてから、衛星信号受信機が安定するまでの間も電源断にさせることができる。このことにより、通信装置部分での省エネルギー化が計れる効果がある。
【図面の簡単な説明】
【図１】本発明の間欠衛星信号測位システムのシステム構成を示す図。
【図２】間欠動作状態における衛星軌道情報の収集方法を説明する図。
【符号の説明】
５０Ａ子局側衛星信号受信機
５０Ｂ親局側衛星信号受信機
１Ａ，１Ｂ電源オン／オフ装置
２Ａ，２Ｂ衛星信号受信測位装置
３Ａ，３Ｂ子局側、親局側通信装置
４Ａ，４Ｂタイミング調整装置
５Ａエフェメリス記憶装置
５Ｂエフェメリス収集記憶装置
６Ａ，６Ｂ衛星選択記憶装置
７アルマナック記憶装置
８子局位置記憶装置
９データ監視局間通信装置[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an intermittent satellite signal positioning system that periodically obtains a highly accurate positioning position using a satellite signal carrier wave, such as monitoring of a landslide area.
[0002]
[Prior art]
When obtaining a highly accurate positioning position using a satellite signal carrier wave, it is necessary to collect data at the same timing for both the master station and the slave station. In general, since the distance between the master station and the slave station is large, it is difficult to perform timing synchronization by transmission. Therefore, in both the master station and the slave station, the satellite signal receiver installed in each station obtains the current time of each station in the time system of the satellite system from the tracked satellite signal, and uses it to collect data at the same timing. It is common.
[0003]
Also, if another arithmetic unit is used to obtain a high-accuracy positioning position, there are disadvantages such as inferior real-time performance and a very large amount of data transfer. Recently, data from one station is transferred to the other station. It is often the case that the positioning position is obtained using the data of both stations.
[0004]
In particular, in a mobile body, in order to obtain an integer bias (an uncertain value corresponding to an integer cycle of a satellite signal carrier wave) indispensable for positioning position calculation, it is common to operate a satellite signal receiver continuously. . However, a system for intermittent positioning on the slave station side has recently been proposed to save energy when the moving speed is extremely slow, such as monitoring landslide areas. A device is devised to send satellite selection information and detailed satellite orbit information from the station to the slave station. For that purpose, the master station side needs to collect detailed satellite orbit information and rough satellite orbit information necessary for determining satellite selection information. In the conventional system, the satellite signal receiver on the master station side is continuously operated. I am letting.
[0005]
[Problems to be solved by the invention]
As described above, in the conventional satellite signal positioning system for intermittent positioning, since the master station side needs to continuously receive, there is a drawback that the master station side cannot save energy. In addition, when the slave station side is intermittently positioned, it often waits for startup from the master station, but the slave station communication device must always be in a standby state to monitor the startup signal from the master station. There was a disadvantage that energy saving could not be achieved in the device part.
[0006]
For this reason, the present invention is to intermittently position the satellite signal receiver on the master station side and the slave station side, and to operate the master station and the slave station communication device only when the positioning position is obtained, It aims at providing the satellite signal positioning system which realized energy saving.
[0007]
[Means for Solving the Problems]
The intermittent satellite signal positioning system according to claim 1 is an intermittent satellite signal positioning system that performs positioning with high accuracy using a satellite carrier phase between a master station side and at least one slave station side. A master station side satellite signal receiver and a master station side communication device that are intermittently operated based on a reference time from a satellite signal, respectively, and the master station side satellite signal receiver receives the same reference time from the satellite signal during the intermittent operation. The satellite orbit information of all the satellites is sequentially acquired, the satellite information to be received is created and stored based on the satellite orbit information, and the detailed satellite orbit information of each satellite is updated from the satellite signal during intermittent operation. Monitor based on the reference time included in the orbit information, and only when updated, intermittent operation is temporarily changed to acquire and store updated detailed orbit information, stored satellite information to be received, updated Detailed gauge Using the information for positioning, the master station side communication device transmits the satellite information to be received and the updated detailed orbit information to the slave station side during the intermittent operation, and the slave station side receives the satellite signal from the satellite signal. A slave station side satellite signal receiver and a slave station side communication device that are intermittently operated based on a reference time, respectively, and the slave station side communication device receives a satellite to be received transmitted from the master station side during the intermittent operation. Information and updated detailed orbit information are received and stored, and the slave side satellite signal receiver uses the stored satellite information to be received and the updated detailed orbit information for positioning during intermittent operation. It is characterized by.
[0008]
The intermittent satellite signal positioning system according to claim 2 is the intermittent satellite signal positioning system according to claim 1, wherein the timing of the intermittent operation of the master station side communication device is different from the timing of the intermittent operation of the master station side satellite signal receiver. The timing of the intermittent operation of the slave station side communication device is different from the timing of the intermittent operation of the slave station side satellite signal receiver.
[0009]
An intermittent satellite signal positioning system according to claim 3 receives a satellite signal on the master station side, measures a current time and tracking data such as a carrier wave phase at a satellite signal receiver, and the satellite signal. Almanac storage device that obtains and stores the approximate satellite orbit information (almanac data) from the data from the receiving positioning device, the approximate satellite orbit information stored in the almanac storage device, the current time obtained from the satellite signal receiving positioning device, and the known A satellite selection storage device for storing satellite information to be received from the master station location information, and detailed satellite orbit information (Femeris data) is obtained from the data from the satellite signal reception positioning device, and a part thereof and FEMERIS collection and storage device for outputting all, tracking data such as carrier phase in the satellite signal receiver, master station position information, and The satellite information to be received from the star selection storage device and the detailed satellite orbit information from the FEMERIS collection storage device are sent to at least one slave station, and the positioning position data sent from each slave station is received, and the satellite Based on the master station side communication device that outputs to the signal reception positioning device, the slave station position storage device that stores the positioning position data via the satellite signal reception positioning device, and the current time obtained from the satellite signal reception positioning device, A timing device that adjusts the operation timing of a power on / off device for intermittent operation, and an on / off control of the satellite signal reception positioning device and the master station side communication device that are adjusted by the timing device at different timings. A master station side device composed of a power on / off device, tracking data such as a carrier phase of the master station sent from the master station side, master station position information, and Receives satellite information and detailed satellite orbit information, outputs each to the satellite signal receiving positioning device, satellite selection storage device, and FEMERIS storage device, and sends the positioning position data from the satellite signal receiving positioning device to the master station side A slave station side communication device, a satellite selection storage device for storing satellite information to be received sent from the master station, and outputting the satellite information to be received to the satellite signal receiving positioning device, and a master station sending the satellite information A detailed satellite orbit information for each of the satellites, and an ephemeris storage device for outputting the detailed satellite orbit information of all the stored satellites to the satellite signal receiving positioning device, and a child based on the satellite information to be received. It receives the satellite signal of the station side, measures the tracking data such as the current time and carrier phase, and the data and the tail data such as the carrier phase at the master station, and the detail information from the ephemeris storage device. The satellite signal receiving positioning device that obtains the positioning position using the star orbit information and the master station position information, and the operation timing of the power on / off device for intermittent operation based on the current time obtained from the satellite signal receiving positioning device And a power on / off device that is adjusted by the timing device and controls on / off of the satellite signal reception positioning device and the slave station side communication device at different timings. It is characterized by comprising one slave station side device.
[0010]
The intermittent satellite signal positioning system according to claim 4 is the intermittent satellite signal positioning system according to claim 3, wherein instead of sending tracking data such as the carrier phase and the parent station position information from the parent station, the carrier phase determined by the parent station side, etc. The corrected tracking data obtained by correcting the tracking data is sent.
[0011]
The intermittent satellite signal positioning system according to claim 5 is the intermittent satellite signal positioning system according to claim 3, wherein instead of sending tracking data such as a carrier phase from the master station and obtaining the positioning position on the slave station side, the carrier phase from the slave station is obtained. Or the like, and the positioning position of each slave station is obtained on the master station side.
[0012]
The intermittent satellite signal positioning system according to claim 6 is the intermittent satellite signal positioning system according to claims 3 to 5, comprising a data monitoring station communication device for transmitting and receiving data to and from the data monitoring station. Even when intermittent operation is in progress, the power on / off device is controlled to turn on the satellite signal receiving positioning device, and the slave station location information stored in the slave station location storage device on the master station side is stored. It is characterized in that it is read via a satellite signal receiving positioning device and sent to a data monitoring station.
[0013]
According to the present invention, similar to the slave station side, the master station side can be operated intermittently by the power on / off device having a very small operating current, so that the master station side can also save energy.
[0014]
Further, since the slave station side communication device does not wait for activation from the master station and the slave station side communication device can also perform intermittent operation synchronized with the satellite system time, energy saving in the communication device portion can be achieved.
[0015]
In addition, the communication device between the master station and the slave station operates only while the positioning position is actually obtained, and the power can be turned off until the satellite signal receiver is stabilized after the satellite signal receiver is turned on. it can. This further saves energy in the communication device portion.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a system configuration of an intermittent satellite signal positioning system of the present invention, and FIG. 2 is a diagram for explaining a method for collecting satellite orbit information.
[0017]
In FIG. 1, the master station side monitors the data via the satellite signal receiver 50B that receives the satellite signal from the antenna 10B, the master station side communication device 3B that transmits and receives data to and from the slave station side, and the antenna 30. The data monitoring inter-station communication device 9 that transmits and receives data to and from the station, the timing adjustment device 4B that receives the time information and outputs a power-off command, and the satellite signal receiver 50B that receives the power-off command It comprises a power on / off device 1B that provides an off command signal.
[0018]
Further, the satellite signal receiver 50B is based on the satellite signal reception positioning device 2B, the almanac storage device 7 that acquires and stores the approximate satellite orbit information (almanac data) of all the satellites, the approximate satellite orbit information of all the satellites, and the like. A satellite selection storage device 6B that stores satellites to be selected and outputs satellite information to be received, an ephemeris collection storage device 5B that acquires and stores detailed satellite orbit information (ephemeris data) of each satellite, and a slave station side It is comprised from the slave station position memory | storage device 8 which memorize | stores the transmitted position data of the slave station.
[0019]
The slave station side receives the satellite signal from the antenna 10A, the satellite signal receiver 50A, the slave station side communication device 3A that transmits and receives data to and from the master station side, and outputs the power-off command in response to the time information. The timing adjustment device 4A and a power-on / off device 1A that receives a power-off command and gives a power-on / off command signal to the satellite signal receiver 50A and the like. The slave station side is similarly configured for a plurality of slave stations as well as one.
[0020]
Further, the satellite signal receiver 50A includes a satellite signal reception positioning device 2A, a satellite selection storage device 6A that outputs satellite information to be received transmitted from the parent station side, and details of each satellite transmitted from the parent station side. An ephemeris storage device 5A that stores satellite orbit information (ephemeris data).
[0021]
Next, the configuration and operation of each device on the master station side will be described.
[0022]
When the satellite signal reception positioning device 2B receives the intermittent operation signal P5 and starts operation, the satellite signal reception positioning device 2B reads the satellite information to be received from the satellite selection storage device 6B and receives the satellite signal. Then, the master station receives the satellite signal from the satellite signal antenna 10B, and first obtains the current time T2 from the received data. The tracking data B1 such as the carrier wave phase in the satellite signal receiver is measured at a certain fixed timing (for example, at the time of the second) from the time when the current time T2 is obtained.
[0023]
While the satellite signal reception positioning device 2B is intermittently operating, the almanac storage device 7 cuts out part of the information from each satellite regarding the approximate satellite orbit information (almanac data) and the reference time of the information, and operates in different operating time zones. Among the collected data, data at the same reference time are stored together.
[0024]
In this way, the approximate satellite orbit information of all satellites is collected and stored during intermittent operation, so that the information can be used whenever necessary.
[0025]
The satellite selection storage device 6B includes the approximate satellite orbit information stored in the almanac storage device 7, the current time T2 obtained from the satellite signal reception positioning device 2B, and the known master station location information input from an input device not explicitly shown. The visible satellite information that can be received at the master station is obtained and stored. Then, the satellite information S1 to be received is output to the satellite signal reception positioning device 2B and the master station side communication device 3B. The satellite information includes a visible satellite number, a moving speed of each station, and a predicted Doppler frequency value of each satellite not including the contribution of the internal oscillator of the receiver. The contribution of the internal oscillator of the receiver is obtained from the satellite signal data tracked when the satellite signal reception positioning device 2B is in operation. Therefore, it can be added to the predicted Doppler frequency and used for the satellite signal reception positioning device 2B. .
[0026]
The FEMERIS collection and storage device 5B extracts and stores a portion of detailed satellite orbit information (ephemeris data) and the reference time of the information from the data from each satellite while the satellite signal reception positioning device 2B is operating. It is checked whether it matches the time and whether it is new satellite data. When the stored reference time coincides with the satellite data up to that point, the stored detailed satellite orbit information is used as it is. On the other hand, only when the reference time is updated or only for new satellite data, the power on / off device is instructed to change the intermittent operation until all the detailed satellite orbit information of the new reference time is collected. Extend the time temporarily. At that time, the satellite number of the detailed satellite orbit information is also stored, and the detailed satellite orbit information of the satellite is sequentially transmitted to the slave station side while the master station side communication device is operating.
[0027]
In this way, during intermittent operation, confirm that the detailed satellite orbit information of each satellite is the same as that of the reference time so far, and if there is a change in the reference time, change the intermittent operation and change the operation time. Since it is temporarily extended and new detailed satellite orbit information is collected and stored and also transmitted to the slave station, the latest detailed satellite orbit information can always be used while performing intermittent operation.
[0028]
The master station side communication device 3B operates by receiving the intermittent operation signal P4, tracking data B1 such as a carrier wave phase in the satellite signal receiver 2B, known master station position information input from an input device (not shown), The satellite information S1 to be received from the satellite selection storage device 6B and the detailed satellite orbit information E2 stored in the Ephemeris collection storage device 5B are transmitted to at least one slave station, and the positioning sent from each slave station. The position data F1 is received and output to the satellite signal reception positioning device 2B.
[0029]
The slave station position storage device 8 stores the positioning position data F1 sent from each slave station, and when requested by the data monitoring inter-station communication device 9, the positioning position data via the satellite signal receiver 2B. F1 is output.
[0030]
In the power on / off device 1B, the power of each device (for the satellite signal receiving positioning device 2B or the master station side communication device 3B) is turned off and the counter operation is started in response to the power cut command from the timing adjustment device. After performing a counter operation corresponding to the power-off time instructed from the timing adjustment device 4B, the power of each device is turned on. Even during the power interruption time period, the satellite signal reception positioning device 2B is temporarily turned on while requested by the inter-data monitoring station communication device 9 or the above-described FEMERIS collection storage device 5B. Since this power on / off device 1B is basically composed of only a low-precision oscillator, counter circuit, and power on / off relay circuit, the current consumption is reduced to one-tenth of that in the standby state of the communication device. Energy consumption can be greatly reduced.
[0031]
The timing adjustment device 4B adjusts each device (for the satellite signal reception positioning device 2B or the master station side communication device 3B) to a desired intermittent interval based on the current time obtained from the satellite signal reception positioning device 2B. Specifically, before stopping the operation of each device, after outputting the difference TC between the current time TA and the power-on desired time TB to the power-on / off device 1B, a power-off command is sent to the power-on / off device 1B. Output. This timing adjustment is performed independently for the satellite signal reception positioning device 2B and the master station side communication device 3B.
[0032]
Actually, the almanac storage device 7, the satellite selection storage device 6B, the F-meris collection storage device 5B, and the slave station position storage device 8 together with the satellite signal reception positioning device 2B constitute a satellite signal receiver 50B. A backup RAM whose contents are held by a backup battery even when the power is turned off is used. Therefore, the satellite signal reception positioning device 2B can always refer to the contents at the time of operation. However, since it does not have an input / output unit, in order to read the contents stored in the slave station position storage device 8, the satellite signal reception tide level device 2B is operated and read out via the satellite signal reception positioning device 2B. It will be.
[0033]
When the position information is requested from a remote data monitoring station, the inter-data monitoring station communication device 9 sends the latest slave station location information stored in the slave station location storage device 8 via the satellite signal reception positioning device 2B. Read out and send to the data monitoring station. Since this request from the data monitoring station is irregular, it enters a standby state after data transmission. And in order to read the content memorize | stored in the slave station position memory | storage device 8, it is necessary to operate the satellite signal receiving positioning apparatus 2B.
[0034]
For this reason, the data monitoring station communication device 9 first outputs the request signal P1 to the power on / off device 1B when the position information is requested from a remote data monitoring station, and operates the satellite signal receiving positioning device 2B. . (Since the master station side communication device does not need to be operated, it is left in the current operating state.) After that, a position information output request is sent to the satellite signal receiving positioning device 2B, and the satellite signal receiving positioning device 2B is passed through. The latest slave station location information F1 stored in the slave station location storage device 8 is obtained and transmitted from the data monitoring station communication device 9 to the data monitoring station.
[0035]
In the present embodiment, the data monitoring station communication device 9 is always in a standby state except for the data transmission period. However, the standby state is further increased based on the current time obtained from the satellite signal receiving positioning device 2B. It is possible to save energy by limiting the time.
[0036]
Next, the configuration on the slave station side and the operation of each device will be described.
[0037]
The slave station side communication device 3A receives tracking data B1 such as the carrier phase of the master station transmitted from the master station side, master station position information, satellite information S1 to be received, and detailed satellite orbit information E2. Each of them is output to the satellite signal reception positioning device 2A, the satellite selection storage device 6A, and the ephemeris storage device 5A, and the positioning position data F1 from the satellite signal reception positioning device 2A is sent to the master station side.
[0038]
The satellite selection storage device 6A stores the satellite information S1 to be received sent from the master station. From the master station side, a predicted Doppler frequency value that does not take into account the contribution of the internal oscillator of the receiver is sent. Since the contribution of the internal oscillator in the satellite signal reception positioning device 2A is obtained from the satellite signal data tracked when the satellite signal reception positioning device 2A is in operation, it may be added to the predicted Doppler frequency.
[0039]
The FEMERIS storage device 5A stores the detailed satellite orbit information E2 of each satellite transmitted from the master station.
[0040]
When the satellite signal reception positioning device 2A receives the intermittent operation signal P2 and starts operation, the satellite signal reception positioning device 2A reads the satellite information S1 to be received from the satellite selection storage device 6A and receives the satellite. First, the current time T1 is obtained from the satellite data.
[0041]
When the current time T1 is known, the tracking data B1 such as the carrier phase on the slave station side is collected at the same timing as the tracking data B1 such as the carrier phase is collected on the master station side. Using the tracking data B1 such as the carrier phase on the slave station side, the tracking data such as the carrier phase on the master station, the detailed satellite orbit information E2 of each satellite stored in the FEMERIS storage device 5A, and the master station position information To obtain a highly accurate positioning position F1. Since there is actually a delay due to the communication device, data on the satellite signal reception positioning device 2A side is stored, and the positioning position calculation is performed when data from the parent station side at the same timing is received.
[0042]
Since the operations of the power on / off device 1A and the timing adjustment device 4A are the same as those of the power on / off device 1B and the timing adjustment device 4B installed on the master station side, the description is omitted here for the sake of simplicity. To do.
[0043]
In the above description, the intermittent operation state, which is a normal operation, has been described, but in order to obtain a highly accurate position, an integer value bias (an uncertain value for an integer cycle of a satellite signal carrier wave) is first required.
[0044]
Therefore, the integer value bias is obtained by setting the intermittent satellite signal positioning system to the continuous operation mode only when the operation is first started. Alternatively, the integer value bias is determined by a method such as separately inputting the initial position of the slave station.
[0045]
In the present invention, detailed satellite orbit information (ephemeris data) and general satellite orbit information (almanac data) are collected by intermittent operation, and the master station side requires continuous operation. It is very different in terms. As described above, by causing the master station side and the slave station side to perform the intermittent operation, the energy saving level can be further increased.
[0046]
As described above, in order to perform intermittent operation on both the master station side and the slave station side and obtain positioning data, the latest detailed satellite orbit information and approximate satellite orbit information are always collected while intermittent operation is performed. It is necessary to keep. The collection method will be described using a GPS satellite as an example.
[0047]
In the case of GPS, the basic message is configured in units of one frame (30 seconds). One frame is composed of five subframes in units of 6 seconds. Of these, the first to third subframes include satellite clock correction data and detailed satellite orbit information along with their reference times, and the fourth and fifth subframes include approximate satellite orbit information and health status. Are included together with their reference times. However, in order to obtain the approximate satellite orbit information for all the satellites, it is necessary to collect the approximate satellite orbit information contained in 25 consecutive frames (master frames), which requires 12.5 minutes. .
[0048]
First, collection of general satellite orbit information will be described. As described above, the approximate satellite orbit information includes the approximate satellite orbit information for each satellite and its reference time sequentially in the data portion for the latter 12 seconds in the repetitive data every 30 seconds. Therefore, if continuous reception is performed for 12.5 minutes (0.5 minutes * 25 frames), the approximate satellite orbit information of all the satellites at the reference time can be obtained. However, the content is not updated at a cycle of 12.5 minutes, but is updated at a cycle of about one day. When updated, the reference time is also updated.
[0049]
In the present invention, using the fact that the content update period is as long as 1 day and repeated every 12.5 minutes, the intermittent period is set to be shorter than 12.5 minutes and asynchronous with the satellite orbit information period. However, although it takes a longer time than 12.5 minutes, the satellite information of all satellites is obtained.
[0050]
The conceptual diagram is shown in FIG. The numbers in FIG. 2 are frame numbers every 30 seconds repeated every 12.5 minutes. The hatched portion or the filled portion is a portion including the approximate satellite orbit information. In this system, since the current time in the time system of the satellite system is obtained, intermittent operation synchronized with the time of the satellite system is possible. Here, let us consider a case where the intermittent period is set to 1 minute and the intermittent operation time is set to 12 seconds including the approximate satellite orbit information. In this case, the shaded portion data cannot be received, but the filled portion data can be received. Thus, for example, during the first 12.5 minutes / cycle, NO. Although 10 frames of data can be received during the operating time, NO. Nine frames of data cannot be received. However, in the next 12.5 minute period, NO. As shown in FIG. 2, the 9-frame data is in the operating time zone and can be received.
[0051]
That is, in the example of FIG. 2, the approximate satellite orbit information of all the satellites can be obtained with a period of 12.5 * 2 = 25 minutes. In FIG. 2, the intermittent time of skipping one frame is used, but it may be intermittent time of skipping two frames, for example, 1, 4, 7 in the first round, 3, 6, 9,.・ Frame data of 2, 5, 8... Can be received in the third round. In this case, the approximate satellite orbit information of all the satellites can be obtained at a period of 12.5 * 3 = 37.5 minutes.
[0052]
These periods are sufficiently shorter than the data update period of one day, and there is no practical problem. In the present invention, in this way, the approximate satellite orbit information of all the satellites is obtained while performing the intermittent operation.
[0053]
Next, detailed satellite orbit information will be described. In the case of GPS, the approximate satellite orbit information is such that each satellite's detailed satellite orbit information and its reference time are included in the first 18 seconds of the data of each satellite that repeats every 30 seconds. If collected, detailed satellite orbit information of each satellite can be obtained. However, the content is not updated every 30 seconds, and is usually updated every 1 to 2 hours. When updated, the reference time is also updated. The data for 18 seconds is further divided into three small frames every 6 seconds, and the reference time is included in all the small frames.
[0054]
In the present invention, the content update cycle is as long as about 1 hour, is repeated every 30 seconds, and the fact that the reference time is included in a small frame every 6 seconds out of 18 seconds is used for detailed satellite orbit information. The frequency of collecting is extremely low. As in the case of the outline satellite orbit information, the concept will be described with reference to FIG. In FIG. 2, the hatched portion and the filled portion are small frames with a portion including detailed satellite orbit information. Here, let us consider a case where the intermittent period is set to 1 minute and the intermittent operation time is set to 6 seconds including a certain small frame. In this case, the shaded portion data cannot be received, but the filled portion data can be received. Therefore, for example, NO. Although the data in the 9th frame cannot be checked, the following NO. Data in 10 frames can be checked.
[0055]
Since each small frame includes a reference time, whether or not the detailed satellite orbit information has been updated can be checked. It is checked whether the reference time of the detailed satellite orbit information of the corresponding satellite stored in the ephemeris collection storage device 5B matches the reference time of the detailed satellite orbit information included in the shaded portion of FIG. Alternatively, it is checked whether the reference time of the detailed satellite orbit information included in the newly acquired filled portion matches the reference time of the detailed satellite orbit information acquired before that. When these do not match, the detailed satellite orbit information is updated, so if the detailed satellite orbit information of this small frame and other small frames is collected, the new detailed satellite orbit information of each satellite is collected. Is obtained.
[0056]
Note that the acquisition of the approximate satellite orbit information and the check of the detailed satellite orbit information may be performed subsequently in the shaded area and the filled area in FIG. 2 or may be performed in different time zones.
[0057]
Also, when a new satellite appears in the visible range and tracking is successful for the first time, detailed satellite orbit information is collected. The frequency at which new satellites appear is short, about once every 20 minutes, and the update interval of detailed satellite orbit information for each satellite is usually about 1 to 2 hours, so the frequency of collecting detailed satellite orbit information is about 20 minutes. It can be very small, about once (18 seconds).
[0058]
Note that when detailed satellite orbit information is collected, the intermittent operation is stopped for a period of time. As described in the configuration diagram of FIG. 1, the power on / off device is connected to the ephemeris collection storage device 5B. The intermittent operation is stopped until the collection of detailed satellite orbit information is completed.
[0059]
In this intermittent satellite signal positioning system, the update of the detailed satellite orbit information is delayed as compared with the case of continuous operation due to the device. However, since both the master station data and the slave station data use the Ephemeris data from the master station in common, the update delay of this degree does not lead to deterioration in accuracy at all, so there is no problem.
[0060]
As described above, according to the present invention, since the master station side can be operated intermittently while collecting the outline and detailed satellite orbit information without any problem, the master station side can also save energy.
[0061]
In addition, since the intermittent operation on the slave station side in the conventional system is configured to take charge of the communication device portion, energy saving cannot be achieved in the communication device portion. In the 1A off / off device, the communication device portion is also intermittently operated in synchronization with the satellite system time, so that the communication device portion can greatly save energy.
[0062]
Further, in the conventional system, there is a system that sends satellite selection information and detailed satellite orbit information of all satellites from the master station side when the slave station starts an intermittent operation in order to shorten the satellite tracking time on the slave station side. In the case of this conventional system, the communication device between the master station and the slave station must be operated before the satellite signal receiver is operated, and must be operated during the operation of the satellite signal receiver. In the present invention, basically, the communication device between the master station and the slave station can be operated only in a situation where a positioning solution is obtained, such as when transmitting a carrier wave phase.
[0063]
In addition, since the satellite arrangement changes slowly, even if the time is different for about 10 minutes, the visible satellite is different by one at most, and the different satellites have a low elevation angle and are tracked within a short time during intermittent positioning operation. It is a difficult satellite to do. Even if the 10 minute time is different, the change of the Doppler frequency is slight. Therefore, if the satellite selection information obtained within 10 minutes is used, no substantial problem occurs.
[0064]
Therefore, in the present embodiment, the satellite selection information obtained when the current time is known at the master station is sent to the slave station side. The satellite signal receiving positioning device 2A refers to the information at the next intermittent operation. Yes. Therefore, with this method, the communication device between the master station and the slave station does not need to send the satellite selection information prior to the operation of the satellite signal receiver, and only needs to be operated in a situation where a positioning solution can be obtained.
[0065]
Further, in the present embodiment, since the FEMERIS storage device 5A is used, it is not necessary to send detailed satellite orbit information of all the satellites when transmitting from the master station within each operation time, and sequentially (for example, within each operation time) Therefore, the communication time for sending detailed satellite orbit information can be shortened to less than 1 second.
[0066]
In addition, as described above, when the positioning solution is obtained, both the master station data and the slave station data, and the ephemeris data sent from the master station are used in common, so that accuracy degradation does not occur even if the ephemeris update is delayed. . Therefore, the communication device between the master station and the slave station only needs to be operated while the positioning position is actually obtained, and the power is cut off after the satellite signal receiver is turned on until the satellite signal receiver is stabilized. Therefore, energy saving can be achieved in the communication device portion.
[0067]
Further, in the present invention, since it is ensured that the same ephemeris data is always used in the master station and the slave station, on the master station side, the tracking data such as the carrier phase on the master station side to be sent to the slave station side is related. A correction amount such as an error of the observed value can be calculated. Therefore, as another embodiment, instead of sending the tracking data such as the carrier phase and the parent station position information from the parent station side, the tracking data such as the carrier phase obtained on the parent station side is corrected, and the corrected tracking is performed. A method of sending data may be adopted.
[0068]
In addition, since the processing load for determining the positioning position is heavy, in multiple slave stations, tracking data such as the carrier wave phase is sent from the master station, and the positioning position is calculated on the slave station side to distribute the processing load. Yes. Alternatively, tracking data such as a carrier wave phase may be sent from the slave station, and the positioning position of each slave station may be obtained on the master station side. In this case, the processing load on the master station increases, so when each slave station data is obtained, the signal tracking at the master station is stopped and only the positioning calculation is performed. You can save time and save energy.
[0069]
【The invention's effect】
In the present invention, the master station side can also be intermittently operated by a power on / off device having a very small operating current, similarly to the slave station side, so that the master station side can also save energy.
[0070]
In addition, the slave station side communication device does not wait for activation from the master station, and the slave station side communication device can also perform intermittent operation in synchronization with the satellite system time, so that there is an effect of saving energy in the communication device portion. .
[0071]
In addition, the communication device between the master station and the slave station operates only while the positioning position is actually obtained, and the power can be turned off until the satellite signal receiver is stabilized after the satellite signal receiver is turned on. it can. This has the effect of saving energy in the communication device portion.
[Brief description of the drawings]
FIG. 1 is a diagram showing a system configuration of an intermittent satellite signal positioning system of the present invention.
FIG. 2 is a diagram illustrating a method for collecting satellite orbit information in an intermittent operation state.
[Explanation of symbols]
50A Slave station side satellite signal receiver
50B Master station side satellite signal receiver
1A, 1B Power on / off device
2A, 2B Satellite signal receiving positioning device
3A, 3B Slave station side, master station side communication device
4A, 4B Timing adjustment device
5A Ephemeris storage device
5B Ephemeris collection storage device
6A, 6B Satellite selection storage device
7 Almanac storage device
8 Slave station location storage device
9 Communication device between data monitoring stations

Claims

An intermittent satellite signal positioning system that performs positioning with high accuracy using a satellite carrier phase between a master station side and at least one slave station side,
The master station side includes a master station side satellite signal receiver and a master station side communication device that are intermittently operated based on a reference time from the satellite signal,
The master station side satellite signal receiver sequentially acquires the approximate satellite orbit information of all the satellites at the same reference time from the satellite signal during the intermittent operation, and creates and stores the satellite information to be received based on the approximate satellite orbit information. Similarly, during the intermittent operation, the update of the detailed satellite orbit information of each satellite is monitored based on the reference time included in the orbit information from the satellite signal, and the updated details are obtained by temporarily changing the intermittent operation only when updated. Obtain and store orbit information, use the stored satellite information to be received and updated detailed orbit information for positioning,
The master station side communication device transmits the satellite information to be received and the updated detailed orbit information to the slave station side during the intermittent operation,
The slave station side includes a slave station side satellite signal receiver and a slave station side communication device that are intermittently operated based on the reference time from the satellite signal,
The slave station side communication device receives and stores the satellite information to be received and the updated detailed orbit information transmitted from the master station side during the intermittent operation,
The slave satellite signal receiver uses the stored satellite information to be received and the updated detailed orbit information for positioning during intermittent operation.

2. The intermittent satellite signal positioning system according to claim 1, wherein the intermittent operation timing of the master station side communication device is different from the intermittent operation timing of the master station side satellite signal receiver and the intermittent operation timing of the slave station side communication device. Is different from the timing of intermittent operation of the slave station side satellite signal receiver.

Satellite signal reception positioning device that receives the satellite signal of the master station and measures tracking data such as the current time and carrier wave phase at the satellite signal receiver, and approximate satellite orbit information from the data from the satellite signal reception positioning device The almanac storage device for obtaining and storing (almanac data), the approximate satellite orbit information stored in the almanac storage device, the current time obtained from the satellite signal receiving positioning device, and the satellite to be received from the known master station position information A satellite selection storage device for storing information, a detailed satellite orbit information (Femeris data) obtained from data from the satellite signal receiving positioning device, and a Femeris collection storage device for outputting a part and all of the information, and Tracking data such as carrier phase in the satellite signal receiver, master station position information, and satellite information to be received from the satellite selection storage device And the detailed satellite orbit information from the FM melis collection storage device to the at least one slave station, the positioning position data sent from each slave station is received, and the master station side communication that outputs to the satellite signal receiving positioning device Operation of the power on / off device for intermittent operation based on the current time obtained from the device, the slave station position storage device for storing the positioning position data via the satellite signal receiving positioning device, and the satellite signal receiving positioning device A timing device that adjusts timing, and a power on / off device that is adjusted by the timing device and that controls the satellite signal reception positioning device and the master station side communication device at different timings. A master station side device,
Receives tracking data such as the carrier phase of the master station sent from the master station side, master station position information, satellite information to be received, and detailed satellite orbit information. And the slave station side communication device that outputs the positioning position data from the satellite signal reception positioning device to the master station side, and stores the satellite information to be received sent from the master station. The satellite selection storage device that outputs the satellite information to be received to the satellite signal receiving positioning device, and the detailed satellite orbit information of each satellite sent from the master station, and the details of all the stored satellites FEMERIS storage device that outputs satellite orbit information to a satellite signal reception positioning device, and receives satellite signals on the slave station side based on the satellite information to be received, and measures tracking data such as current time and carrier phase, Satellite signal reception positioning device that obtains a positioning position using the master data, the data of the tail of the carrier wave at the master station, detailed satellite orbit information from the ephemeris storage device, and the master station position information, and the satellite signal reception positioning A timing device that adjusts the operation timing of the power on / off device for intermittent operation based on the current time obtained from the device, and the satellite signal reception positioning device and the slave station side communication device that are adjusted by the timing device. At least one slave station side device configured with a power on / off device that performs on / off control at different timings;
Intermittent satellite signal positioning system characterized by comprising.

4. In the intermittent satellite signal positioning system according to claim 3, instead of sending tracking data such as carrier phase and parent station position information from the master station, corrected tracking data obtained by correcting tracking data such as carrier phase obtained on the master station side is used. An intermittent satellite signal positioning system characterized by sending.

4. In the intermittent satellite signal positioning system according to claim 3, instead of sending tracking data such as carrier phase from the master station and obtaining the positioning position on the slave station side, tracking data such as carrier phase is sent from the slave station and An intermittent satellite signal positioning system characterized by determining the positioning position of each slave station.

6. The intermittent satellite signal positioning system according to claim 3, further comprising a data monitoring station communication device that transmits and receives data to and from the data monitoring station, and is in an intermittent operation when position information is requested from the data monitoring station. Even if the power on / off device is controlled to turn on the satellite signal reception positioning device, the slave station position information stored in the slave station location storage device on the master station side is read via the satellite signal reception positioning device, An intermittent satellite signal positioning system characterized by being sent to a data monitoring station.