JP3592155B2

JP3592155B2 - Distance measuring device

Info

Publication number: JP3592155B2
Application number: JP26794199A
Authority: JP
Inventors: 康裕川西; 廣記新原
Original assignee: 日本電気エンジニアリング株式会社
Priority date: 1999-09-22
Filing date: 1999-09-22
Publication date: 2004-11-24
Anticipated expiration: 2019-09-22
Also published as: JP2001091636A

Description

【０００１】
【発明の属する技術分野】
本発明は測距装置に関し、特に人工衛星と管理局間の距離を測定する測距装置に関する。
【０００２】
【従来の技術】
人工衛星（以下、衛星という）の管制を行う上で、衛星の地球との絶対位置を正確に知る必要がある。その必須事項として、管制局から見た方位角と仰角の角度検出と測距（衛星と管制局との距離を求めること）があげられる。本発明では、このうち測距についての提案を行う。
【０００３】
衛星と管制局との距離を測定する場合、管制局より衛星に対し、測距信号を送出し、衛星から中継されてきた測距信号を受信して、その送信から受信までの折り返し時間を測定することにより、管制局から衛星までの距離を求めることができる。
【０００４】
しかし、この測定には測距信号が管制局の送信機及び受信機を通過することにより発生する遅延時間が含まれるため、あらかじめ送信機と受信機の局内遅延時間を測定する必要があった。これまでは、局内遅延時間の測定には送信機の出力周波数と受信機の入力周波数が異なるため送信周波数を受信周波数に変換するための周波数変換装置、切替器及び接続ケーブルが必要であり、これらの持つ遅延時間を含んで局内折り返しの遅延時間を測定していた。そして、測距信号の衛星折り返し遅延時間から局内折り返し遅延時間の値を差引くことにより管制局から衛星までの距離算出に必要な時間を算出していた。
【０００５】
次に、従来の測距装置の一例について説明する。図６は従来の測距装置の一例の構成図である。図６を参照すると、従来の測距装置５０は、測距設備５１と、送信機５２と、切替器５３と、給電機５４と、初段受信機５５と、切替器５６と、受信機５７と、送受周波数変換装置５８と、指向性アンテナ５９とを含んで構成されていた。この測距装置５０が管制局を構成している。そして、測距装置５０から衛星６０に対し測距信号を送出することにより、測距装置５０は衛星６０と測距装置５０間の距離を測定する。
【０００６】
次に、測距装置５０の動作について説明する。測距設備５１から送出された測距信号Ｓ１は送信機５２にて周波数変換、変調及び電力増幅された後、切替器５３、給電器５４及び指向性アンテナ５９を経由し、衛星６０に送出される。衛星６０では受信した信号を復調して測距信号Ｓ１を取得し、さらにその測距信号Ｓ１で監理局からの搬送波（監理局搬送波）とは異なる搬送波周波数を有する搬送波（衛星搬送波）を変調して測距装置５０に送信する。測距装置５０の初段受信機５５は指向性アンテナ５９及び給電機５４を介してこの変調信号を受信する。初段受信機５５はこの変調信号を切替器５６を介して受信機５７へ送出する。受信機５７はこの変調信号を復調して測距信号Ｓ１を取得し測距設備５１へ送出する。
【０００７】
次に、切替器５３，５６は給電機５４側から送受周波数変換装置５８側に切替えられる。そして、送信機５２からの送信信号が切替器５３を介して送受周波数変換装置５８に入力される。送受周波数変換装置５８では送信信号の周波数が受信信号の周波数に変換される。そして、受信信号の周波数に変換された信号は切替器５６を介して受信機５７に入力される。受信機５７では入力信号が復調され測距信号Ｓ１が取得され、その測距信号Ｓ１は測距設備５１へ送出される。
【０００８】
測距設備５１は測距信号Ｓ１を出力した時刻Ｔ１と、切替器５３，５６で折返した（局内折返しの）測距信号Ｓ１を受信した時刻Ｔ２と、衛星６０経由（衛星折返し）の測距信号Ｓ１を受信した時刻Ｔ３とから、
（Ｔ３−Ｔ１）−（Ｔ２−Ｔ１）＝Ｔ３−Ｔ２
により衛星６０と測距装置５０間の距離測定に必要な遅延時間を算出する。
【０００９】
しかし、この従来の測距装置の一例の第１の問題点は、測距信号Ｓ１の衛星６０折り返し遅延時間から局内折り返し遅延時間の値を差引く必要があるが、局内折り返し遅延時間は正確には測定ができないことである。その理由は、局内折り返しの遅延時間には、送受信周波数変換装置５８、切替器５３，５６及び送受信周波数変換装置５８と切替器５３，５６間を接続する接続ケーブルの遅延時間が含まれ、これらの誤差は正確に測定することができないためである。
【００１０】
第２の問題点は、衛星折り返し遅延時間と局内折り返し遅延時間を同時に測定することができないため、周囲温度の変化により発生する遅延時間の変動誤差が生じることである。その理由は、衛星折り返しと局内折り返しを同時に実施した場合、受信機に同一周波数の信号が入力されてしまうため、切替えが必要となるためである。
【００１１】
第３の問題点は、局内折り返し試験器が故障すると測距が行えないことである。その理由は、局内の遅延を測定することがでず、衛星折り返し遅延時間と局内遅延時間の差を求めることができないためである。
【００１２】
一方、第２の問題点を解決する手段が特開平７−４３４５６号公報（以下、文献という）に開示されている。次に、この文献開示の測距装置について説明する。図７は文献開示の測距装置の構成図である。なお、前述の図６と同様の構成部分については同一番号を付し、その説明を省略する。図７を参照すると、測距装置７０は、測距設備５１と、送信機５２と、給電機５４と、初段受信機５５と、受信機５７と、減衰器７１と、拡散変調器７２と、ＰＮコード発生器７３と、送受周波数変換装置５８と、指向性アンテナ５９とを含んで構成されている。この測距装置７０が管制局を構成している。そして、測距装置７０から衛星６０に対し測距信号を送出することにより、測距装置７０は衛星６０と測距装置７０間の距離を測定する。
【００１３】
ここで、図６記載の測距装置５０との相違点は切替器５３，５６を削除し、減衰器７１と、拡散変調器７２と、ＰＮコード発生器７３とを追加したことである。即ち、測距装置７０では局内折返しの測距信号Ｓ１を減衰器７１と、拡散変調器７２と、ＰＮコード発生器７３とを介して取得している。具体的には、送信機５２からの送信信号を減衰器７１を介して拡散変調器７２にて拡散変調する。そして、その拡散変調信号を送受周波数変換装置５８にて受信周波数に変換し受信機５７に入力する。受信機５７ではその拡散変調信号を逆拡散さらに復調して測距信号Ｓ１を取得し距離設備５１に送出する。このように測距装置７０では送信機５２からの送信信号を局内折り返し時に拡散変調したため切替器５３，５６による信号の切替えが不要となり、もって衛星折り返し遅延時間と局内折り返し遅延時間とを同時に測定することが可能となる。
【００１４】
【発明が解決しようとする課題】
しかし、この文献開示の技術をもってしても前述の第１及び第３の問題点は解決しない。そこで本発明の目的は、送受信周波数変換装置を含む局内折り返し設備を不要とし、しかも衛星折り返し遅延時間と局内折り返し遅延時間を同時に測定することが可能な測距装置を提供することにある。
【００１５】
【課題を解決するための手段】
前記課題を解決するために本発明は、監理局から対象物に対し第１信号を送信する送信手段と、前記第１信号を受信した前記対象物から前記監理局に返送される第２信号を受信する第１及び第２受信手段と、前記送信手段が前記第１信号を送信した時刻と前記第２受信手段が前記第２信号を受信した時刻とに基づき前記監理局と前記対象物間の距離を測定する測定手段とを含む測距装置であって、その測距装置は前記送信手段から送信される前記第１信号のうち少なくとも前記第１受信手段を飽和させるに必要なレベルの信号を前記第１受信手段へ入力させる帰還手段を含み、前記測定手段は前記第１受信手段へ前記第１信号の一部が入力された時刻に基づき前記監理局内の折返し遅延時間を算出することを特徴とする。
【００１６】
本発明によれば、第１信号の一部を受信手段へ入力させ、その入力された時刻に基づき監理局内の折返し遅延時間を算出するため、送受信周波数変換装置を含む局内折り返し設備を不要とし、しかも衛星折り返し遅延時間と局内折り返し遅延時間を同時に測定することが可能となる。
【００１７】
【発明の実施の形態】
まず、本発明の概要について説明する。図１に示すように、正確な局内折り返し遅延時間を求める方法として、誤差を生じる局内折り返し試験設備は使用しないこととする。目的は、送受信周波数変換装置、切替器及び接続ケーブルにて構成される局内折り返し設備にて発生する遅延誤差を排除し、局内折り返し遅延時間の測定精度を高めることである。給電機１には通常、送信機５２側の電力が受信機５７側に回り込まないようにフィルタを挿入するが、本発明では送信側の電力を受信側へ回し込み、拡張帯域特性を有する初段の受信機（低雑音増幅装置）２を用いてその漏洩してくる測距信号電力により受信機５７が飽和することを利用する。
【００１８】
以下、本発明の実施の形態について添付図面を参照しながら説明する。図１は本発明に係る測距装置の最良の実施の形態の構成図である。なお、同図において従来例（図６）と同様の構成部分については同一番号を付し、その説明を省略する。図１を参照すると、測距装置１０は測距設備５１と、送信機５２と、給電機１と、初段受信機２と、受信機５７と、指向性アンテナ５９とを含んで構成されている。この測距装置１０が管制局を構成している。そして、測距装置１０から衛星６０に対し測距信号を送出することにより、測距装置１０は衛星６０と測距装置１０間の距離を測定する。
【００１９】
衛星６０からは衛星自身の状態を示すテレメトリ信号Ｓ２が測距信号Ｓ１に重畳されて測距装置１０に対し送信されている。図２はこの測距装置１０が使用する周波数帯域を示す周波数帯域図である。同図に示すように、管制局から衛星に対して送信される信号（コマンドと測距信号Ｓ１）の周波数帯域は衛星から管制局に対して送信される信号（テレメトリ信号Ｓ２と測距信号Ｓ１）の周波数帯域よりも高い周波数の帯域が割当てられている。
【００２０】
次に、給電機１について説明する。図３は給電機１内に設けられたフィルタの通過帯域特性図である。従来は送信帯域の周波数成分が受信部へ漏れ込みを起こさないように給電機１にフィルタを挿入し周波数特性を調整していたが、本発明では送信帯域の周波数成分を通過させることとする。図３を参照すると、従来、衛星６０からの受信信号であるテレメトリ信号Ｓ２と測距信号Ｓ１に対しては減衰量を小さくし、衛星６０に対する送信信号であるコマンドと測距信号Ｓ１に対しては減衰量を大きくするようフィルタを構成していた。これにより、受信機５７において衛星６０からの信号は受信するが送信機５２からの回り込み信号は受信しないようにしていた。これに対し、本発明では送信機５２からの回り込み信号を受信するようにコマンドと測距信号Ｓ１の送信に使用する周波数帯域の減衰量を従来よりも小さくしている。
【００２１】
次に、初段受信機２について説明する。初段受信機２は低雑音増幅装置にて構成されている。図４は初段受信機２に入力される信号の周波数特性図である。同図を参照すると、初段受信機２は衛星６０からの受信信号であるテレメトリ信号Ｓ２及び測距受信信号Ｓ１と、送信機５２からの回り込み信号（測距送信信号Ｓ１）の両者が受信可能となるよう受信周波数帯域が従来よりも拡張されている。又、同図を参照すると、測距送信信号Ｓ１のレベルの方がテレメトリ信号Ｓ２及び測距受信信号Ｓ１のレベルより高くなっているが、これは測距送信信号Ｓ１が少なくとも初段受信機２を飽和させるに必要なレベルを有していることを示している。
【００２２】
次に、測距装置１０の動作について説明する。本提案の構成では測距設備５１から送信機５２を経由し給電機１から衛星６０に測距信号Ｓ１が送信される。又、衛星６０からの測距信号Ｓ１は、給電機１から受信機５７を経由し測距設備５１にて受信される。この間に、実際の測距に不要な局内折り返し信号を取り込むための構成（送受信周波数変換器、入出力部切り替え器、接続ケーブル）は存在しない。又、給電機１から初段受信器（低雑音増幅装置）２までの路長が遅延過誤差となるが、本発明では初段受信機２が給電機１の出力部に導波管にて直結されているため、局内折り返し時間の誤差とはならない。
【００２３】
図５は測距装置１０の動作を示すタイミングチャートである。同図において、（Ａ）は測距装置５１から出力される測距信号Ｓ１の出力波形を示し、（Ｂ）は初段受信機２におけるテレメトリ信号Ｓ２の受信波形を示し、（Ｃ）は測距装置５１に入力される衛星折返しの測距信号Ｓ１の受信波形を示す。
【００２４】
図１及び図５を参照すると、測距設備５１より、測距信号Ｓ１が図５（Ａ）のタイミングで出力される。この時刻をＴ１とする。出力された信号Ｓ１は、送信機５２にて周波数変換、変調及び電力増幅され、給電機１及び指向性アンテナ５９を介して衛星６０に送出される。このとき測距信号Ｓ１の電力の一部は給電機１にて受信ポートに分岐され、給電機１に直結された初段受信機２（低雑音増幅装置）に入力される。
【００２５】
すると、初段受信機２である低雑音増幅装置は過入力を起こし飽和する。衛星６０からはテレメトリ信号Ｓ２が発信されているが、初段受信機２が飽和すると受信スペクトラムが圧縮され、テレメトリ信号Ｓ２のレベルが見掛上、下がったように見える。即ち、初段受信器２（低雑音増幅装置）が飽和することにより、初段受信器２の利得が下がり、受信機５７において衛星からのテレメトリ信号Ｓ２の受信レベルが低下する。図５（Ｂ）に示すようにその動作レベルが低下する時刻をＴ２とする。この（Ｔ２−Ｔ１）が局内折り返し遅延時間に相当する。
【００２６】
次に衛星６０から測距信号Ｓ１がテレメトリ信号Ｓ２に重畳され送信されてくる。初段受信機２にて電力増幅された信号は受信機５７にて周波数変換及び復調されたのち測距設備５１にて測距信号Ｓ１を取り出し測距設備５１で測定した衛星折り返しの時刻Ｔ３が求められる（図５（Ｃ）参照）。
【００２７】
測距設備５１での衛星折り返しの遅延時間は（Ｔ３−Ｔ１）にて求められる。ここで、衛星折り返し（Ｔ３−Ｔ１）と局内折り返し（Ｔ２−Ｔ１）から求める衛星測距のための遅延時間は
（Ｔ３−Ｔ１）−（Ｔ２−Ｔ１）＝Ｔ３−Ｔ２
にて求められる。即ち、初段受信機２の動作レベルが低下した時刻Ｔ２から衛星折り返し信号を受信した時刻Ｔ３の差を求めれば管制局から衛星６０までの折り返し時間を求められ、これにより管制局から衛星６０までの正確な遅延時間を求めることができる。
【００２８】
【発明の効果】
本発明によれば、監理局から対象物に対し第１信号を送信する送信手段と、前記第１信号を受信した前記対象物から前記監理局に返送される第２信号を受信する受信手段と、前記送信手段が前記第１信号を送信した時刻と前記受信手段が前記第２信号を受信した時刻とに基づき前記監理局と前記対象物間の距離を測定する測定手段とを含む測距装置であって、その測距装置は前記送信手段から送信される前記第１信号の一部を前記受信手段へ入力させる帰還手段を含み、前記測定手段は前記受信手段へ前記第１信号の一部が入力された時刻に基づき前記監理局内の折返し遅延時間を算出するため、送受信周波数変換装置を含む局内折り返し設備を不要とし、しかも衛星折り返し遅延時間と局内折り返し遅延時間を同時に測定することが可能となる。
【００２９】
具体的には、本発明の第１の効果は、正確な測距ができることである。第１の効果が得られる理由は、局内折り返し用設備を必要としないため、折り返し用送受信周波数変換器、切替器及び接続ケーブルによる誤差を生じることがないためである。本発明の第２の効果は、正確な測距ができることである。第２の効果が得られる理由は、局内折り返しと衛星折り返しを同時に行うことができるため、切替時間内に発生する測定誤差をなくすことができるためである。本発明の第３の効果は、折り返し用試験設備が存在しなくても測距ができることである。第３の効果が得られる理由は、測距のための専用の折り返し試験設備が不要であるため、折り返し試験設備が故障したことにより測距ができなくなるということがなくなるためである。
【図面の簡単な説明】
【図１】本発明に係る測距装置の最良の実施の形態の構成図である。
【図２】測距装置１０が使用する周波数帯域を示す周波数帯域図である。
【図３】給電機１内に設けられたフィルタの通過帯域特性図である。
【図４】初段受信機２に入力される信号の周波数特性図である。
【図５】測距装置１０の動作を示すタイミングチャートである。
【図６】従来の測距装置の一例の構成図である。
【図７】文献開示の測距装置の構成図である。
【符号の説明】
１給電機
２初段受信機
１０測距装置
５１測距設備
５２送信機
５７受信機
５９指向性アンテナ[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a distance measuring device, and particularly to a distance measuring device that measures a distance between an artificial satellite and a management station.
[0002]
[Prior art]
In order to control an artificial satellite (hereinafter referred to as a satellite), it is necessary to accurately know the absolute position of the satellite with respect to the earth. The essential items include detection of the azimuth angle and elevation angle as viewed from the control station and ranging (finding the distance between the satellite and the control station). The present invention proposes distance measurement.
[0003]
When measuring the distance between the satellite and the control station, the control station sends a ranging signal to the satellite, receives the ranging signal relayed from the satellite, and measures the return time from transmission to reception By doing so, the distance from the control station to the satellite can be obtained.
[0004]
However, since this measurement includes a delay time generated when the ranging signal passes through the transmitter and the receiver of the control station, it is necessary to measure the in-station delay time of the transmitter and the receiver in advance. Until now, measurement of intra-station delay time requires a frequency converter, switch, and connection cable to convert the transmission frequency to the reception frequency because the output frequency of the transmitter and the input frequency of the receiver are different. The delay time of the loopback in the station was measured including the delay time of. Then, the time required for calculating the distance from the control station to the satellite is calculated by subtracting the value of the intra-station return delay time from the satellite return delay time of the ranging signal.
[0005]
Next, an example of a conventional distance measuring device will be described. FIG. 6 is a configuration diagram of an example of a conventional distance measuring device. Referring to FIG. 6, a conventional distance measuring apparatus 50 includes a distance measuring equipment 51, a transmitter 52, a switch 53, a power supply 54, a first-stage receiver 55, a switch 56, and a receiver 57. , A transmission / reception frequency conversion device 58 and a directional antenna 59. This distance measuring device 50 constitutes a control station. Then, by sending a ranging signal from the ranging device 50 to the satellite 60, the ranging device 50 measures the distance between the satellite 60 and the ranging device 50.
[0006]
Next, the operation of the distance measuring device 50 will be described. The ranging signal S1 transmitted from the ranging equipment 51 is frequency-converted, modulated, and power-amplified by the transmitter 52, and then transmitted to the satellite 60 via the switch 53, the power supply 54, and the directional antenna 59. You. The satellite 60 demodulates the received signal to obtain a ranging signal S1, and further modulates a carrier (satellite carrier) having a carrier frequency different from the carrier from the supervisory station (supervisory station carrier) with the ranging signal S1. To the distance measuring device 50. The first-stage receiver 55 of the distance measuring device 50 receives the modulated signal via the directional antenna 59 and the power supply 54. The first-stage receiver 55 sends out the modulated signal to the receiver 57 via the switch 56. The receiver 57 demodulates the modulated signal to obtain a distance measurement signal S1 and sends it to the distance measurement equipment 51.
[0007]
Next, the switches 53 and 56 are switched from the power supply 54 to the transmission / reception frequency converter 58. Then, a transmission signal from the transmitter 52 is input to the transmission / reception frequency conversion device 58 via the switch 53. The transmission / reception frequency conversion device 58 converts the frequency of the transmission signal to the frequency of the reception signal. Then, the signal converted into the frequency of the received signal is input to the receiver 57 via the switch 56. In the receiver 57, the input signal is demodulated to obtain a distance measurement signal S1, and the distance measurement signal S1 is transmitted to the distance measurement equipment 51.
[0008]
The distance measuring equipment 51 outputs the distance measuring signal S1 at time T1, the time T2 at which the switches 53 and 56 receive the return (intra-station return) distance measuring signal S1, and the distance measurement via the satellite 60 (satellite return). From time T3 when the signal S1 is received,
(T3-T1)-(T2-T1) = T3-T2
Calculates the delay time required for measuring the distance between the satellite 60 and the distance measuring device 50.
[0009]
However, a first problem of this conventional distance measuring apparatus is that it is necessary to subtract the value of the return delay time in the station from the return delay time of the satellite 60 of the ranging signal S1, but the return delay time in the office is accurately calculated. Means that measurement is not possible. The reason is that the delay time of the loopback in the office includes the delay time of the transmission / reception frequency conversion device 58, the switches 53 and 56, and the connection cable connecting the transmission / reception frequency conversion device 58 and the switches 53 and 56. This is because the error cannot be measured accurately.
[0010]
A second problem is that since the satellite return delay time and the intra-station return delay time cannot be measured simultaneously, a delay time variation error occurs due to a change in ambient temperature. The reason is that, when the satellite return and the intra-station return are performed at the same time, a signal of the same frequency is input to the receiver, so that switching is required.
[0011]
A third problem is that distance measurement cannot be performed if the in-station loopback tester fails. The reason is that the delay in the station cannot be measured, and the difference between the satellite return delay time and the intra-station delay time cannot be obtained.
[0012]
On the other hand, means for solving the second problem is disclosed in Japanese Patent Application Laid-Open No. 7-43456 (hereinafter referred to as literature). Next, a distance measuring device disclosed in this document will be described. FIG. 7 is a configuration diagram of a distance measuring device disclosed in the literature. The same components as those in FIG. 6 described above are denoted by the same reference numerals, and description thereof will be omitted. Referring to FIG. 7, the distance measuring device 70 includes a distance measuring device 51, a transmitter 52, a power supply 54, a first-stage receiver 55, a receiver 57, an attenuator 71, a spread modulator 72, It includes a PN code generator 73, a transmission / reception frequency conversion device 58, and a directional antenna 59. This distance measuring device 70 constitutes a control station. Then, by transmitting a ranging signal to the satellite 60 from the ranging device 70, the ranging device 70 measures the distance between the satellite 60 and the ranging device 70.
[0013]
Here, the difference from the distance measuring apparatus 50 shown in FIG. 6 is that the switches 53 and 56 are deleted, and an attenuator 71, a spread modulator 72, and a PN code generator 73 are added. That is, the ranging device 70 acquires the ranging signal S1 of the return in the station via the attenuator 71, the spread modulator 72, and the PN code generator 73. Specifically, the transmission signal from the transmitter 52 is spread-modulated by the spread modulator 72 via the attenuator 71. Then, the spread modulation signal is converted into a reception frequency by the transmission / reception frequency conversion device 58 and input to the receiver 57. The receiver 57 despreads and further demodulates the spread modulation signal to obtain a distance measurement signal S1 and sends it to the distance equipment 51. As described above, in the distance measuring apparatus 70, the transmission signal from the transmitter 52 is spread-modulated at the time of looping back in the station, so that signal switching by the switches 53 and 56 becomes unnecessary. It becomes possible.
[0014]
[Problems to be solved by the invention]
However, the first and third problems described above are not solved even by the technology disclosed in this document. SUMMARY OF THE INVENTION It is an object of the present invention to provide a distance measuring apparatus which eliminates the need for in-station loopback equipment including a transmission / reception frequency conversion apparatus and is capable of simultaneously measuring a satellite loopback delay time and a loopback delay time in a station.
[0015]
[Means for Solving the Problems]
In order to solve the above-described problem, the present invention provides a transmitting unit that transmits a first signal from a supervisory station to an object, and a second signal that is returned from the object that has received the first signal to the supervisory station. First and second receiving means for receiving, a time between the control station and the object based on a time at which the transmitting means transmits the first signal and a time at which the second receiving means receives the second signal; And a measuring means for measuring a distance. The distance measuring apparatus outputs a signal of a level necessary to saturate at least the first receiving means among the first signals transmitted from the transmitting means. Feedback means for inputting to the first receiving means, wherein the measuring means calculates a return delay time in the supervisory station based on a time when a part of the first signal is input to the first receiving means. And
[0016]
According to the present invention, a part of the first signal is input to the receiving means, and the return delay time in the supervisory station is calculated based on the input time. Moreover, the satellite return delay time and the intra-station return delay time can be measured simultaneously.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
First, an outline of the present invention will be described. As shown in FIG. 1, as a method for obtaining an accurate intra-station loop-back delay time, it is assumed that an intra-station loop test equipment that causes an error is not used. It is an object of the present invention to eliminate a delay error generated in an intra-station loop-back facility composed of a transmission / reception frequency converter, a switch, and a connection cable, and to improve the accuracy of measuring the intra-station loop-back delay time. Normally, a filter is inserted into the power supply 1 so that the power of the transmitter 52 does not sneak into the receiver 57. In the present invention, the power of the transmission side is diverted to the reception side, and the first stage having the extended band characteristic is provided. The fact that the receiver 57 is saturated by the leaked ranging signal power using the receiver (low noise amplifier) 2 is used.
[0018]
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a configuration diagram of a preferred embodiment of a distance measuring apparatus according to the present invention. In the figure, the same components as those of the conventional example (FIG. 6) are denoted by the same reference numerals, and description thereof will be omitted. Referring to FIG. 1, a distance measuring apparatus 10 includes a distance measuring equipment 51, a transmitter 52, a power supply 1, a first-stage receiver 2, a receiver 57, and a directional antenna 59. . This distance measuring device 10 constitutes a control station. Then, by sending a ranging signal from the ranging device 10 to the satellite 60, the ranging device 10 measures the distance between the satellite 60 and the ranging device 10.
[0019]
From the satellite 60, a telemetry signal S2 indicating the state of the satellite itself is superimposed on the ranging signal S1 and transmitted to the ranging device 10. FIG. 2 is a frequency band diagram showing a frequency band used by the distance measuring apparatus 10. As shown in the figure, the frequency band of the signal (command and ranging signal S1) transmitted from the control station to the satellite is the signal (telemetry signal S2 and ranging signal S1) transmitted from the satellite to the control station. ) Is assigned to a frequency band higher than the frequency band.
[0020]
Next, the power supply device 1 will be described. FIG. 3 is a passband characteristic diagram of a filter provided in the power supply 1. Conventionally, a filter has been inserted into the power supply 1 to adjust the frequency characteristic so that the frequency component of the transmission band does not leak into the receiving unit. However, in the present invention, the frequency component of the transmission band is passed. Referring to FIG. 3, conventionally, attenuation is reduced for a telemetry signal S2 and a ranging signal S1 which are reception signals from a satellite 60, and a command and a ranging signal S1 which are transmission signals to the satellite 60 are reduced. Has configured a filter to increase the amount of attenuation. Thereby, the receiver 57 receives the signal from the satellite 60 but does not receive the sneak signal from the transmitter 52. On the other hand, in the present invention, the attenuation of the frequency band used for transmitting the command and the distance measurement signal S1 is made smaller than that of the related art so as to receive the wraparound signal from the transmitter 52.
[0021]
Next, the first-stage receiver 2 will be described. The first-stage receiver 2 is configured by a low-noise amplifier. FIG. 4 is a frequency characteristic diagram of a signal input to the first-stage receiver 2. Referring to the figure, the first-stage receiver 2 is capable of receiving both a telemetry signal S2 and a ranging reception signal S1 which are reception signals from the satellite 60, and a wraparound signal (ranging transmission signal S1) from the transmitter 52. The receiving frequency band has been extended more than before. Referring to FIG. 3, the level of the distance measurement transmission signal S1 is higher than the levels of the telemetry signal S2 and the distance measurement reception signal S1. This indicates that the level has the level required for saturation.
[0022]
Next, the operation of the distance measuring device 10 will be described. In the proposed configuration, the ranging signal S1 is transmitted from the power supply device 1 to the satellite 60 from the ranging device 51 via the transmitter 52. The ranging signal S1 from the satellite 60 is received by the ranging equipment 51 from the power feeding device 1 via the receiver 57. During this time, there is no configuration (transmission / reception frequency converter, input / output unit switcher, connection cable) for capturing an intra-station return signal unnecessary for actual distance measurement. The path length from the feeder 1 to the first-stage receiver (low-noise amplifier) 2 causes an excessive delay error. In the present invention, the first-stage receiver 2 is directly connected to the output of the feeder 1 by a waveguide. Therefore, there is no error in the intra-station turnaround time.
[0023]
FIG. 5 is a timing chart showing the operation of the distance measuring apparatus 10. In the figure, (A) shows the output waveform of the ranging signal S1 output from the ranging device 51, (B) shows the reception waveform of the telemetry signal S2 in the first stage receiver 2, and (C) shows the ranging. 6 shows a reception waveform of a ranging signal S <b> 1 of a satellite return input to the device 51.
[0024]
Referring to FIG. 1 and FIG. 5, the ranging signal 51 is output from the ranging device 51 at the timing of FIG. This time is defined as T1. The output signal S1 is frequency-converted, modulated, and power-amplified by the transmitter 52, and transmitted to the satellite 60 via the power supply 1 and the directional antenna 59. At this time, a part of the power of the ranging signal S1 is branched to the receiving port by the power supply 1 and is input to the first-stage receiver 2 (low-noise amplifier) directly connected to the power supply 1.
[0025]
Then, the low-noise amplifier, which is the first-stage receiver 2, causes over-input and saturates. Although the telemetry signal S2 is transmitted from the satellite 60, when the first-stage receiver 2 is saturated, the reception spectrum is compressed, and the level of the telemetry signal S2 appears to have dropped. That is, when the first-stage receiver 2 (low-noise amplifier) is saturated, the gain of the first-stage receiver 2 decreases, and the reception level of the telemetry signal S2 from the satellite in the receiver 57 decreases. The time when the operation level decreases as shown in FIG. This (T2-T1) corresponds to the intra-station turnaround delay time.
[0026]
Next, the ranging signal S1 is superimposed on the telemetry signal S2 and transmitted from the satellite 60. The signal that has been power-amplified by the first-stage receiver 2 is frequency-converted and demodulated by the receiver 57, and then the distance measuring signal S1 is taken out by the distance measuring equipment 51, and the satellite return time T3 measured by the distance measuring equipment 51 is obtained. (See FIG. 5C).
[0027]
The delay time of the return of the satellite in the distance measuring equipment 51 is obtained by (T3-T1). Here, the delay time for satellite ranging obtained from the satellite return (T3-T1) and the intra-station return (T2-T1) is (T3-T1)-(T2-T1) = T3-T2.
Is required. That is, if the difference between the time T2 at which the operation level of the first-stage receiver 2 decreases and the time T3 at which the satellite return signal is received is obtained, the return time from the control station to the satellite 60 can be obtained. An accurate delay time can be obtained.
[0028]
【The invention's effect】
According to the present invention, transmitting means for transmitting a first signal from a supervisory station to an object, and receiving means for receiving a second signal returned from the object having received the first signal to the supervisory station, A distance measuring device including a measuring unit that measures a distance between the supervisory station and the object based on a time when the transmitting unit transmits the first signal and a time when the receiving unit receives the second signal. Wherein the distance measuring device includes feedback means for inputting a part of the first signal transmitted from the transmitting means to the receiving means, and the measuring means transmits a part of the first signal to the receiving means. Since the return delay time in the supervisory station is calculated based on the input time, the need for an in-station return facility including a transmission / reception frequency converter is eliminated, and the satellite return delay time and the in-station return delay time can be measured simultaneously. That.
[0029]
Specifically, a first effect of the present invention is that accurate distance measurement can be performed. The reason why the first effect is obtained is that no equipment is required for the loopback transmission / reception frequency converter, the switching device, and the connection cable because the loopback equipment is not required. A second effect of the present invention is that accurate distance measurement can be performed. The second effect is obtained because the intra-station return and the satellite return can be performed at the same time, so that a measurement error occurring within the switching time can be eliminated. A third effect of the present invention is that distance measurement can be performed without the need for a folding test facility. The reason why the third effect can be obtained is that a dedicated loopback test facility for distance measurement is not required, so that the failure of the loopback test facility does not prevent the distance measurement from being performed.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a preferred embodiment of a distance measuring apparatus according to the present invention.
FIG. 2 is a frequency band diagram showing a frequency band used by the distance measuring apparatus 10.
FIG. 3 is a passband characteristic diagram of a filter provided in the power supply device 1.
FIG. 4 is a frequency characteristic diagram of a signal input to a first-stage receiver 2.
FIG. 5 is a timing chart showing an operation of the distance measuring apparatus 10.
FIG. 6 is a configuration diagram of an example of a conventional distance measuring device.
FIG. 7 is a configuration diagram of a distance measuring device disclosed in the literature.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Power supply 2 First stage receiver 10 Distance measuring device 51 Distance measuring equipment 52 Transmitter 57 Receiver 59 Directional antenna

Claims

Transmitting means for transmitting a first signal from the control station to the object, first and second receiving means for receiving a second signal returned from the object receiving the first signal to the control station, A distance measuring device that measures a distance between the control station and the object based on a time at which the transmitting means transmits the first signal and a time at which the second receiving means receives the second signal; A device,
Feedback means for inputting a signal of a level necessary to saturate at least the first receiving means among the first signals transmitted from the transmitting means to the first receiving means, wherein the measuring means comprises a first receiving means A distance measuring apparatus, wherein a return delay time in the supervisory station is calculated based on a time when a part of the first signal is input to the means.

The measuring means calculates the object return delay time from the time when the first signal is transmitted and the time when the second signal is received, based on the object return delay time and the return delay time in the control station. distance measuring apparatus according to claim 1, wherein the calculating the aliasing delay time of the supervision station.

Unlike frequency of said second signal of said first signal, said first receiving means measuring according to claim 1 or 2, characterized by having a band capable of receiving the first and second signals Distance device.

The feedback means includes a first pass band for passing the second signal with a predetermined attenuation, a second pass band for passing the first signal with an attenuation larger than the attenuation of the second signal, distance measuring apparatus according to 3 claim 1, characterized in that it comprises a third pass band for passing a signal other than the first and second signals with a large amount of attenuation than the attenuation of the first signal.

A telemetry signal is constantly transmitted from the object to the supervisory station, and the second signal is superimposed on the transmission signal. When a part of the first signal is input to the first receiving means, the telemetry signal is transmitted. distance measuring apparatus according to claims 1 in which the reception level of the signal, characterized in that drops to 4 or.

The distance measuring device according to any one of claims 1 to 5, wherein the object is an artificial satellite.