JPH09127229A - Specifying method for position of transmitting station by stationary satellite - Google Patents
Specifying method for position of transmitting station by stationary satelliteInfo
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- JPH09127229A JPH09127229A JP30502495A JP30502495A JPH09127229A JP H09127229 A JPH09127229 A JP H09127229A JP 30502495 A JP30502495 A JP 30502495A JP 30502495 A JP30502495 A JP 30502495A JP H09127229 A JPH09127229 A JP H09127229A
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- satellite
- station
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- Radar Systems Or Details Thereof (AREA)
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Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、静止衛星に向けて
電波を送信した送信局の位置を、静止衛星を用いて特定
することが可能な、静止衛星による送信局位置特性方法
に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a geostationary satellite transmitting station position characteristic method capable of specifying the position of a transmitting station that has transmitted radio waves to a geostationary satellite using the geostationary satellite. .
【０００２】[0002]
【従来の技術】近来の衛星通信技術の進展にともなって
小型で可搬型の地球局設備が利用できるようになり、斯
かる可搬型の地球局設備を用いると、どのような場所に
でも通信の必要に応じて機動的に衛星通信回線を設けら
れるようになった。ところがその反面、地球局設備の不
具合や誤操作、あるいは不法な操作によって不要な電波
が発射され、それが運用中の通信回線に妨害を与える、
ということが憂慮されるようになっている。そのよう
な、衛星通信の適正な運用を阻害する干渉波が発生する
と、その対処のためには、先ず干渉波の発生源である干
渉局の位置を特定することが肝要である。2. Description of the Related Art With the recent development of satellite communication technology, small and portable earth station equipment has become available. If such portable earth station equipment is used, communication can be performed anywhere. Satellite communication lines can now be flexibly installed as needed. However, on the other hand, unnecessary radio waves are emitted due to faulty or incorrect operation of the earth station equipment or illegal operation, which interferes with the operating communication line,
That is becoming a concern. When such an interference wave that hinders the proper operation of the satellite communication is generated, it is important to first identify the position of the interference station which is the source of the interference wave.
【０００３】そこで、干渉局の位置を決定するために用
いられている従来の方法を、図６に基づいて説明する。
例えば、第１通信衛星Ｓ１が、第１地球局Ｕ１の信号を
第２地球局Ｕ２へ中継している状態において、干渉局Ｘ
の信号がこの中継回線に干渉を与えたとすると、第２地
球局Ｕ２では、第１地球局Ｕ１の信号と干渉局Ｘの信号
が重なって受信され、それと同じものを、干渉の監視の
ために設けた地球局である監視局Ｋにおいて受信する。
また、第１通信衛星Ｓ１の付近に第２通信衛星Ｓ２を配
置し、この第２通信衛星Ｓ２は上記第１通信衛星Ｓ１と
同じチャンネルを用いつつ他の回線の中継を行っていた
ものとする。[0003] A conventional method used to determine the position of an interfering station will now be described with reference to FIG.
For example, in a state where the first communication satellite S1 is relaying the signal of the first earth station U1 to the second earth station U2, the interference station X
Suppose that this signal interferes with this relay line, the second earth station U2 receives the signal of the first earth station U1 and the signal of the interfering station X in an overlapping manner, and the same signal is used to monitor the interference. The signal is received by the monitoring station K which is the earth station provided.
Further, it is assumed that a second communication satellite S2 is arranged near the first communication satellite S1, and this second communication satellite S2 relays another line while using the same channel as the first communication satellite S1. .
【０００４】そして、干渉局Ｘの干渉信号は第１通信衛
星Ｓ１に向けられたものであるが、アンテナのサイドロ
ーブを通じてわずかながら第２通信衛星Ｓ２にも干渉を
与える。監視局Ｋでは、干渉を受けた第２通信衛星Ｓ２
からの信号をも合わせて受信する。このため、干渉局Ｘ
から送信された干渉信号は、第１，第２通信衛星Ｓ１，
Ｓ２を夫々経由して監視局Ｋに到達することとなる。従
って、監視局Ｋにおいて第１，第２通信衛星Ｓ１，Ｓ２
から夫々到達した信号を相関処理すると、同じ干渉信号
が、「干渉局Ｘ→第１通信衛星Ｓ１→監視局Ｋ」という
第１経路を経て干渉波が監視局Ｋに到達するのに要した
時間と、「干渉局Ｘ→第２通信衛星Ｓ２→監視局Ｋ」と
いう第２経路を経て干渉波が監視局Ｋに到達するのに要
した時間との差を求めることができる。[0004] The interference signal of the interfering station X is directed to the first communication satellite S1, but slightly interferes with the second communication satellite S2 through the side lobe of the antenna. In the monitoring station K, the second communication satellite S2
The signal from is also received. Therefore, the interference station X
The interference signals transmitted from the first and second communication satellites S1,
It reaches the monitoring station K via each of S2. Therefore, at the monitoring station K, the first and second communication satellites S1, S2
Are correlated, the same interference signal takes the time required for the interference wave to reach the monitoring station K via the first path of "interference station X → first communication satellite S1 → monitoring station K". And the time required for the interference wave to reach the monitoring station K via the second route “interference station X → second communication satellite S2 → monitoring station K”.
【０００５】上記のようにして求めた干渉波受信の時間
差と第１，第２通信衛星Ｓ１，Ｓ２の位置情報とに基づ
いて、“干渉局Ｘから第１通信衛星Ｓ１までの距離”と
“干渉局Ｘから第２通信衛星Ｓ２までの距離”との差を
知ることができる。そして、これらの距離差に基づい
て、第１通信衛星Ｓ１と第２通信衛星Ｓ２を焦点とする
ひとつの回転双曲面に地表面が交差して成すひとつの曲
線が測位曲線として取得され、この曲線は干渉局Ｘがそ
の上にあることを示唆する。すなわち、地表面上におけ
る干渉局Ｘの存在可能性を示す点の集合として測位曲線
が表れるのである。なお、このような測位の原理は、
「双曲線航法」として周知である。Based on the time difference of interference wave reception and the position information of the first and second communication satellites S1 and S2 obtained as described above, "the distance from the interference station X to the first communication satellite S1" and " It is possible to know the difference between the distance "from the interfering station X to the second communication satellite S2". Then, based on these distance differences, one curve formed by intersecting the ground surface with one rotational hyperboloid having the first communication satellite S1 and the second communication satellite S2 as focal points is obtained as a positioning curve, and this curve is obtained. Implies that interfering station X is over it. That is, the positioning curve appears as a set of points indicating the possibility of the presence of the interference station X on the ground surface. The principle of such positioning is
Also known as "hyperbolic navigation."
【０００６】図７は、第１通信衛星Ｓ１と第２通信衛星
Ｓ２による干渉波受信に基づいて得た測位曲線の例を示
すものであり、測位曲線は、第１通信衛星Ｓ１と第２通
信衛星Ｓ２を結ぶ直線が指す方向に依存する。従って、
第１通信衛星Ｓ１と第２通信衛星Ｓ２とを結ぶ直線の方
位が変化すると、同一の干渉局Ｘから干渉波を受けた場
合であっても、その方位の変化に伴って測位曲線が変化
することとなる。そして、第１通信衛星Ｓ１と第２通信
衛星Ｓ２は、共に静止衛星として許される範囲内で動き
を伴うので、時間とともに両通信衛星Ｓ１，Ｓ２の相対
位置が変化することとなって、第１計測時における第１
測位曲線Ｃ１（図７中、実線で示す）と、第２計測時に
おける第２測位曲線Ｃ２（図７中、破線で示す）とは異
なったものとなる。FIG. 7 shows an example of a positioning curve obtained based on interference wave reception by the first communication satellite S1 and the second communication satellite S2. The positioning curve is based on the first communication satellite S1 and the second communication satellite. It depends on the direction indicated by the straight line connecting the satellite S2. Therefore,
When the azimuth of the straight line connecting the first communication satellite S1 and the second communication satellite S2 changes, the positioning curve changes with the change of the azimuth even if an interference wave is received from the same interference station X. It will be. Since the first communication satellite S1 and the second communication satellite S2 both move within a range permitted as a geostationary satellite, the relative positions of both communication satellites S1 and S2 change with time, and First at the time of measurement
The positioning curve C1 (shown by a solid line in FIG. 7) is different from the second positioning curve C2 (shown by a broken line in FIG. 7) at the time of the second measurement.
【０００７】このようにして得られた第１測位曲線Ｃ１
と第２測位曲線Ｃ２とは、各々が干渉局Ｘの存在可能性
を示唆するものであることから、両測位曲線Ｃ１，Ｃ２
の交点に干渉局Ｘが位置していると看做すことができる
のである。[0007] The first positioning curve C1 obtained in this manner.
And the second positioning curve C2 each indicate the possibility of the presence of the interfering station X, so that both the positioning curves C1 and C2
It can be considered that the interference station X is located at the intersection of.
【０００８】[0008]
【発明が解決しようとする課題】しかしながら、上述し
たような送信位置決定方法によって、干渉局等の送信局
の位置を特定するためには、干渉を受けた通信衛星の付
近に、当該通信衛星と同じチャンネルを中継する他の通
信衛星が存在していなければならず、そのような通信衛
星が存在しない場合には、干渉が発生しても干渉波を送
信している送信局の位置を特定することができない。However, in order to specify the position of a transmitting station such as an interfering station by the above-described method for determining a transmitting position, it is necessary to place the transmitting station near the interfering communication satellite. There must be another communication satellite that relays the same channel, and if there is no such communication satellite, the position of the transmitting station transmitting the interference wave is specified even if interference occurs. Can not do.
【０００９】また、仮に干渉を受けた通信衛星の近傍に
他の通信衛星が存在していたとしても、他の通信衛星が
干渉局から受ける干渉信号は、干渉局のアンテナのサイ
ドローブから放射されたものであるため、受信レベルが
低い。そのため監視局での相関処理において、信号到達
時間差の正確な測定が困難となり、延いては位置決定に
少なからぬ誤差をもたらす可能性がある。Further, even if another communication satellite is present near the communication satellite that has received the interference, the interference signal received by the other communication satellite from the interference station is radiated from the side lobe of the antenna of the interference station. The reception level is low. Therefore, in the correlation processing at the monitoring station, it is difficult to accurately measure the signal arrival time difference, which may result in considerable errors in position determination.
【００１０】さらに、各通信衛星は、静止衛星として認
められる静止位置保持領域内で微妙に位置を変えている
に過ぎないため、測定時間の異なる２つの測位曲線を取
得したとしても、両測位曲線は略々重なり合った状態に
しかならず、０度に近い角度をもって交わることとな
る。このため、両測位曲線の交点を特定すること自体が
実際上困難であり、送信局の位置を特定できるとは言え
なかった。Further, since each communication satellite only slightly changes its position within the stationary position holding region recognized as a geostationary satellite, even if two positioning curves having different measurement times are obtained, both positioning curves are obtained. Are almost in an overlapped state, and they cross at an angle close to 0 degrees. For this reason, it is actually difficult to specify the intersection of both positioning curves, and it cannot be said that the position of the transmitting station can be specified.
【００１１】そこで、本発明は、送信局の位置特定を高
精度で行えるような静止衛星による送信位置測定方法の
提供を目的とするものである。SUMMARY OF THE INVENTION It is an object of the present invention to provide a transmission position measuring method using a geostationary satellite so that the position of a transmitting station can be specified with high accuracy.
【００１２】[0012]
【課題を解決するための手段】上記課題を解決するため
に、第１発明に係る静止衛星による送信局の位置特定方
法は、静止衛星と認められる静止位置保持領域（Ａ）内
に２機の通信衛星（例えば、第１通信衛星Ｓ１，第２通
信衛星Ｓ２）を配し、これら２機の通信衛星は夫々同じ
チャンネルの電波を中継可能であると共に、両通信衛星
を結ぶ直線の方位が計時的に変化するものとし、送信局
（例えば、地球局Ｘ）から送信された電波が各通信衛星
に到達するまでの時間差に基づいて地表面上における送
信局の存在可能性を示す測位曲線を複数取得し、取得し
た複数の測位曲線（例えば、第１測曲線Ｌ１，第２測位
曲線Ｌ２）の交点を以て送信局の位置を特定するように
した。In order to solve the above-mentioned problems, the method for identifying the position of a transmitting station by means of a geostationary satellite according to the first aspect of the present invention is a method for identifying two stations within a geostationary position holding area (A) recognized as a geostationary satellite. A communication satellite (for example, a first communication satellite S1 and a second communication satellite S2) is arranged, and these two communication satellites can relay radio waves of the same channel, and the direction of a straight line connecting both communication satellites is timed. And a plurality of positioning curves indicating the existence possibility of the transmitting station on the ground surface based on the time difference until the radio wave transmitted from the transmitting station (for example, the earth station X) reaches each communication satellite. The position of the transmitting station is specified by the intersection of the acquired positioning curves (for example, the first measurement curve L1 and the second positioning curve L2).
【００１３】上記のような静止衛星による送信局の位置
特定方法によれば、国際規約によって定められた有限の
静止位置保持量域内で２機の通信衛星が移動して、２機
の通信衛星を結ぶ直線の方位が計時的に変化することか
ら、測位曲線を求めた時間に応じて測位曲線には比較的
大きな変化が生ずることとなり、各測位曲線の交点を求
めることが容易となる。なお、測位曲線が２本定まれば
送信位置を特定することは可能であるが、３本以上の測
位曲線の交点（或いは交差領域）を参照することによ
り、誤差範囲を推認することもできる。According to the method for specifying the position of a transmitting station using a geostationary satellite as described above, two communication satellites move within a finite geostationary position holding amount area defined by international regulations, and the two communication satellites are moved. Since the azimuth of the connecting straight line changes with time, a relatively large change occurs in the positioning curve in accordance with the time when the positioning curve is obtained, and it becomes easy to obtain the intersection of each positioning curve. Note that if two positioning curves are determined, it is possible to specify the transmission position, but it is also possible to estimate the error range by referring to the intersection (or intersection area) of three or more positioning curves.
【００１４】また、２機の通信衛星は、互いに等距離を
保ちながら等速円運動を行うものとしても良い。斯くす
れば、２機の通信衛星を結ぶ直線の方位が９０゜に近い
大きな角度を以て交わるような時刻を選んで測位曲線を
求めることが容易となり、２つの測位曲線も比較的大き
な角度を持って交わることとなり、交点の特定が容易と
なる。The two communication satellites may perform a constant-velocity circular motion while maintaining the same distance from each other. By doing so, it is easy to obtain a positioning curve by selecting a time at which the azimuth of a straight line connecting the two communication satellites crosses at a large angle close to 90 °, and the two positioning curves also have a relatively large angle. As a result, the intersection can be easily specified.
【００１５】さらに、第２発明に係る静止衛星による送
信局位置特定方法によれば、静止衛星と認められる静止
位置保持領域（Ｂ）内に３機以上の通信衛星（例えば、
第１通信衛星Ｓ１，第２通信衛星Ｓ２，第３通信衛星Ｓ
３）を配し、各通信衛星は夫々同じチャンネルの電波を
中継可能であると共に、通信衛星群中の２機で構成する
ペア通信衛星（例えば、第１通信衛星Ｓ１と第２通信衛
星Ｓ２より成る第１ペア通信衛星）を結ぶ直線（ａ）の
方位が他のペア通信衛星（例えば、第２通信衛星Ｓ２と
第３通信衛星Ｓ３より成る第２ペア通信衛星）を結ぶ直
線（ｂ）の方位と交差するように配置し、送信局（例え
ば、地球局Ｘ）から送信された電波が各ペア通信衛星の
各通信衛星に到達する時間差に基づいて地表面上におけ
る送信局の存在可能性を示す測位曲線をペア通信衛星毎
に取得し、取得した複数の測位曲線の交点を以て送信局
の位置を特定するようにした。Further, according to the method for specifying the position of a transmitting station using a geostationary satellite according to the second aspect of the present invention, three or more communication satellites (for example,
First communication satellite S1, second communication satellite S2, third communication satellite S
3), each communication satellite is capable of relaying radio waves of the same channel, and a pair communication satellite (for example, from the first communication satellite S1 and the second communication satellite S2) composed of two units in the communication satellite group. Of the straight line (a) connecting the first pair of communication satellites (a) and (b) of the straight line (b) connecting the other pair of communication satellites (for example, the second pair of communication satellites S2 and S3). It is arranged so as to intersect with the azimuth, and based on the time difference at which the radio wave transmitted from the transmitting station (for example, the earth station X) arrives at each communication satellite of each pair communication satellite, the possibility of the transmission station on the ground surface is determined The positioning curve shown is acquired for each pair of communication satellites, and the position of the transmitting station is specified based on the intersection of the acquired plural positioning curves.
【００１６】上記のような静止衛星による送信局の位置
特定方法によれば、国際規約によって定められた有限の
静止位置保持量域内に配された３機以上の通信衛星群で
２組以上のペア通信衛星を構成すると共に、各ペア通信
衛星を結ぶ直線の方位が交差するような配置としたの
で、各ペア通信衛星毎の測位曲線を略々同時に取得し、
各測位曲線の交点を求めることが容易となる。なお、測
位曲線が２本定まれば送信位置を特定することができる
ので、ペア通信衛星は最低２組あれば良いが、３組以上
のペア通信衛星から各々測位曲線を取得して、３本以上
の測位曲線の交点（或いは交差領域）を参照するものと
すれば、送信局の位置特定における誤差範囲を推認する
こともできる。According to the above-described method for specifying the position of a transmitting station using geostationary satellites, two or more pairs of three or more communication satellite groups arranged within a finite geostationary position holding amount area defined by international regulations. Since the communication satellites were configured and arranged so that the directions of the straight lines connecting the paired communication satellites intersected, the positioning curves for each paired communication satellite were acquired almost simultaneously,
It is easy to find the intersection of each positioning curve. If two positioning curves are determined, the transmission position can be specified. Therefore, it is sufficient that at least two pairs of communication satellites are used. However, three positioning satellites are obtained from three or more pairs of communication satellites. By referring to the intersection (or intersection area) of the above-described positioning curves, it is possible to estimate an error range in specifying the position of the transmitting station.
【００１７】また、全ての通信衛星は、互いに等距離を
保ちながら等速円運動を行うものとしても良い。Further, all the communication satellites may perform a constant velocity circular motion while keeping the same distance from each other.
【００１８】[0018]
【発明の実施の形態】次に、本発明に係る静止衛星によ
る送信局の位置特定方法の実施形態を添付図面に基づい
て説明する。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a method for specifying the position of a transmitting station by a geostationary satellite according to the present invention will be described with reference to the accompanying drawings.
【００１９】図１に示すのは、２機の通信衛星による送
信局の位置特定方法により、干渉局の位置を特定する実
施形態を示すものである。FIG. 1 shows an embodiment in which the position of an interfering station is specified by a method of specifying the position of a transmitting station using two communication satellites.
【００２０】先ず、静止衛星は、地球に対して完全に静
止しているのではなく、有限な大きさの空間領域の中に
保持される事をもって静止衛星と見なす。その領域、す
なわち静止位置保持領域の広がりは、国際規約により緯
度及び経度方向それぞれに０．２度である。従って、通
信衛星が静止位置保持領域から逸脱しないように常に管
制が施される必要があるものの、この領域内においては
通信衛星は任意に動きまわることが許される。First, a geosynchronous satellite is regarded as a geosynchronous satellite if it is not completely stationary with respect to the earth but is held in a space area of a finite size. The area, that is, the extension of the stationary position holding area is 0.2 degrees in each of the latitude and longitude directions according to international regulations. Therefore, although it is necessary to always control the communication satellite so as not to deviate from the stationary position holding area, the communication satellite is allowed to move freely in this area.
【００２１】そこで、一つの静止位置保持領域Ａの中に
２機の通信衛星として、第１通信衛星Ｓ１と第２通信衛
星Ｓ２を配備し、両通信衛星Ｓ１，Ｓ２の運用を同じ管
制局Ｋにおいて行うものとする。この静止位置保持領域
Ａ内における第１，第２通信衛星Ｓ１，Ｓ２の配置構成
の詳細は、図２に示すようなものとしてある。すなわ
ち、これら第１，第２通信衛星Ｓ１，Ｓ２の２通信衛星
が一つの円軌道の直径の両端に在る、という配置関係を
維持しながら回転円運動を行うように、上記管制局Ｋで
衛星管制を行うのである。Therefore, the first communication satellite S1 and the second communication satellite S2 are provided as two communication satellites in one stationary position holding area A, and the operation of both communication satellites S1 and S2 is controlled by the same control station K. Shall be performed. Details of the arrangement of the first and second communication satellites S1 and S2 in the stationary position holding area A are as shown in FIG. That is, in the control station K, the two communication satellites of the first and second communication satellites S1 and S2 perform a rotating circular motion while maintaining an arrangement relationship of being at both ends of the diameter of one circular orbit. It does satellite control.
【００２２】上記のような第１，第２通信衛星Ｓ１，Ｓ
２を同一の静止位置保持領域Ａ内に配した状態で、第１
地球局Ｕ１が第２地球局Ｕ２に向けて通信を行うとき
は、通信のチャンネルに応じて第１，第２通信衛星Ｓ
１，Ｓ２の何れか一方がその中継を受け持つ。このとき
衛星通信の利用者は、静止位置保持領域Ａの全体が一つ
の通信衛星であると看做すことができ、中継を受け持つ
のが何れの通信衛星であるかを意識する必要はない。そ
のため各地球局Ｕ１，Ｕ２では、静止位置保持領域Ａの
全体をメインローブ内に含むようなアンテナを用いる。The first and second communication satellites S1, S as described above
2 in the same stationary position holding area A,
When the earth station U1 performs communication toward the second earth station U2, the first and second communication satellites S correspond to communication channels.
One of S1 and S2 is responsible for the relay. At this time, the user of the satellite communication can regard the whole of the stationary position holding area A as one communication satellite, and does not need to be aware of which communication satellite is responsible for the relay. Therefore, each of the earth stations U1 and U2 uses an antenna that includes the entire stationary position holding area A in the main lobe.
【００２３】ここで、第１通信衛星Ｓ１が中継を受け持
っていたある一つのチャンネルに、地球局Ｘからの干渉
信号が混入したとする。それに応じて他方の第２通信衛
星Ｓ２も、予備に有する中継器を動作させ、干渉を受け
たチャンネルを中継できるようにする。すなわち、同一
の静止位置保持領域Ａ内に配した各通信衛星Ｓ１，Ｓ２
は、共に他方の通信衛星の持つチャンネルを互いにバッ
クアップ可能な構成としてあり、使用中のチャンネルの
何れかが干渉を受けた際には、第１通信衛星Ｓ１と第２
通信衛星Ｓ２が共に干渉を受けたチャンネルを中継する
のである。なお、干渉波による干渉を受けることに基づ
くチャンネル中継の切替は、管制局Ｋの制御によって行
う。Here, it is assumed that an interference signal from the earth station X is mixed in one channel which the first communication satellite S1 is in charge of relaying. In response, the other second communication satellite S2 also operates the spare repeater so that it can relay the interfered channel. That is, each of the communication satellites S1, S2 arranged in the same stationary position holding area A
Are configured so that the channels of the other communication satellites can be backed up to each other, and when any of the used channels receives interference, the first communication satellite S1 and the second communication satellite
The communication satellite S2 relays the interference channel. The switching of the channel relay based on the interference by the interference wave is performed under the control of the control station K.
【００２４】そして、地球局Ｘの信号は第１，第２通信
衛星Ｓ１，Ｓ２を各々経由して管制局Ｋへ到達すること
となり、管制局Ｋでは信号の相関処理により、同じ干渉
信号が「地球局Ｘ→第１通信衛星Ｓ１→管制局Ｋ」とい
う第１経路を経て管制局Ｋに到達するまでに要した時間
と「地球局Ｘ→第２通信衛星Ｓ２→管制局Ｋ」の第２経
路を経て管制局Ｋに到達するまでに要した時間との差を
測定する。この時間差に基づいて、地球局Ｘの存在可能
性を示す第１測位曲線Ｌ１を取得することができる（図
３中、実線で示す）。Then, the signal from the earth station X reaches the control station K via the first and second communication satellites S1 and S2, respectively. The time required to reach the control station K via the first route of “earth station X → first communication satellite S1 → control station K” and the second time of “earth station X → second communication satellite S2 → control station K” The difference from the time required to reach the control station K via the route is measured. Based on this time difference, a first positioning curve L1 indicating the possibility of the presence of the earth station X can be obtained (shown by a solid line in FIG. 3).
【００２５】上記のようにして第１測位曲線Ｌ１を取得
した測定基準時から数時間が経過した後に同様の測定を
行い、第２測位曲線Ｌ２（図３中、破線で示す）を取得
すると、測定基準時からの経過時間に応じて第１通信衛
星Ｓ１と第２通信衛星Ｓ２とを結ぶ直線の方位が変化し
ているので、取得した第１測位曲線Ｌ１と第２測位曲線
Ｌ２とは異なったものとなる。When several hours have passed since the measurement reference time when the first positioning curve L1 was obtained as described above, the same measurement was performed, and the second positioning curve L2 (shown by a broken line in FIG. 3) was obtained. Since the direction of the straight line connecting the first communication satellite S1 and the second communication satellite S2 changes according to the elapsed time from the measurement reference time, the acquired first positioning curve L1 and the obtained second positioning curve L2 are different. It will be.
【００２６】例えば、第１通信衛星Ｓ１と第２通信衛星
Ｓ２とが略々２４時間周期で１回の円運動を行うものと
仮定すると、測定基準時における第１，第２通信衛星Ｓ
１，Ｓ２を結ぶ直線の方位ａ（図２中、実線で示す）
が、６時間後には方位ｂ（図２中、破線で示す）に変化
し、方位ａから略々９０゜回転したこととなるので、第
１測位曲線Ｌ１と第２測位曲線Ｌ２も９０゜に近い角度
をもって交わることとなる。よって、干渉波の発信源で
ある地球局Ｘの位置を示す第１測位曲線Ｌ１と第２測位
曲線Ｌ２との交点を明確に特定できるのである。For example, assuming that the first communication satellite S1 and the second communication satellite S2 make one circular motion approximately every 24 hours, the first and second communication satellites S1 and M2 at the measurement reference time are used.
Direction a of a straight line connecting 1 and S2 (shown by a solid line in FIG. 2)
However, after 6 hours, the direction changes to the direction b (indicated by a broken line in FIG. 2), and the rotation is substantially 90 ° from the direction a, so that the first positioning curve L1 and the second positioning curve L2 also change to 90 °. They will meet at a close angle. Therefore, the intersection of the first positioning curve L1 and the second positioning curve L2 indicating the position of the earth station X which is the source of the interference wave can be clearly specified.
【００２７】上記した２機の通信衛星による送信局の特
定方法においては、静止位置保持領域内に２機の通信衛
星を配備することと、両通信衛星を結ぶ直線の方位を計
時的に変化させるという条件のみで、干渉信号等の目標
とする信号を送信した送信局を特定することができると
いう利点があるものの、送信局の位置を特定するために
は、両通信衛星を結ぶ直線の方位がある程度変化するの
を待って再度測位曲線を取得しなければならないため
に、位置特定の即時性という観点からは、必ずしも望ま
しいものではない。そこで、次に送信局の位置特定を即
時的に行える送信局の特定方法について説明する。In the above-described method for specifying a transmitting station by using two communication satellites, two communication satellites are provided in the stationary position holding area, and the direction of a straight line connecting both communication satellites is timely changed. Only under the condition that there is an advantage that the transmitting station that transmitted the target signal such as the interference signal can be specified, but in order to specify the position of the transmitting station, the direction of the straight line connecting both communication satellites must be Since the positioning curve has to be acquired again after waiting for some change, it is not always desirable from the viewpoint of the immediacy of the position specification. Therefore, a method of specifying a transmitting station that can immediately specify the position of the transmitting station will be described.
【００２８】図４に示すのは、３機以上の通信衛星によ
る送信局の位置特定方法により、干渉局の位置を即時に
特定する実施形態を示すものである。FIG. 4 shows an embodiment in which the position of an interfering station is immediately specified by a method of specifying the position of a transmitting station by three or more communication satellites.
【００２９】一つの静止位置保持領域Ｂの中に３機の通
信衛星として、第１通信衛星Ｓ１と第２通信衛星Ｓ２と
第３通信衛星Ｓ３を配備し、各通信衛星Ｓ１，Ｓ２，Ｓ
３の運用を同じ管制局Ｋにおいて行うものとする。この
静止位置保持領域Ｂ内における第１〜第３通信衛星Ｓ１
〜Ｓ３の配置構成の詳細は、図５に示すようなものとし
てある。すなわち、これら第１〜第３通信衛星Ｓ１〜Ｓ
３の各通信衛星が一つの正円軌道上で正三角形を成す、
という配置関係を維持しながら回転円運動を行うよう
に、上記管制局Ｋで衛星管制を行うのである。In one stationary position holding area B, a first communication satellite S1, a second communication satellite S2, and a third communication satellite S3 are provided as three communication satellites, and each communication satellite S1, S2, S
Operation 3 is performed in the same control station K. The first to third communication satellites S1 in the stationary position holding area B
Details of the arrangement configuration of S3 are as shown in FIG. That is, the first to third communication satellites S1 to S
3, each communication satellite forms an equilateral triangle in one circular orbit,
The satellite control is performed by the control station K so as to perform the rotating circular motion while maintaining the above arrangement relationship.
【００３０】上記のような第１〜第３通信衛星Ｓ１〜Ｓ
３を同一の静止位置保持領域Ｂ内に配した状態で、第１
地球局Ｕ１が第２地球局Ｕ２に向けて通信を行うとき
は、通信のチャンネルに応じて第１〜第３通信衛星Ｓ１
〜Ｓ３の何れか一つがその中継を受け持つ。このとき衛
星通信の利用者は、静止位置保持領域Ｂの全体が一つの
通信衛星であると看做すことができ、中継を受け持つの
が何れの通信衛星であるかを意識する必要はない。その
ため各地球局Ｕ１，Ｕ２では、静止位置保持領域Ｂの全
体をメインローブ内に含むようなアンテナを用いる。The first to third communication satellites S1 to S as described above
3 in the same stationary position holding area B,
When the earth station U1 performs communication toward the second earth station U2, the first to third communication satellites S1 are used according to the communication channel.
-S3 is responsible for the relay. At this time, the user of the satellite communication can regard the entire stationary position holding area B as one communication satellite, and does not need to be aware of which communication satellite is responsible for the relay. Therefore, each of the earth stations U1 and U2 uses an antenna that includes the entire stationary position holding area B in the main lobe.
【００３１】ここで、第１通信衛星Ｓ１が中継を受け持
っていたある一つのチャンネルに、地球局Ｘからの干渉
信号が混入したとする。それに応じて、他の第２，第３
通信衛星Ｓ２，Ｓ３も予備に有する中継器を動作させ、
干渉を受けたチャンネルを中継できるようにする。すな
わち、同一の静止位置保持領域Ｂ内に配した各通信衛星
Ｓ１〜Ｓ３は、共に他の通信衛星の持つチャンネルを互
いにバックアップ可能な構成としてあり、使用中のチャ
ンネルの何れかが干渉を受けた際には、第１〜第３通信
衛星Ｓ１〜Ｓ３の全てが干渉を受けたチャンネルを中継
するのである。なお、干渉波による干渉を受けることに
基づくチャンネル中継の切替は、管制局Ｋの制御によっ
て行う。Here, it is assumed that an interference signal from the earth station X is mixed in one channel which the first communication satellite S1 is in charge of relaying. The other second and third
The communication satellites S2 and S3 also operate the repeaters that are provided as spares,
Be able to relay the channel that suffered interference. That is, each of the communication satellites S1 to S3 arranged in the same stationary position holding area B has a configuration in which channels of other communication satellites can be backed up to each other, and any one of the channels in use suffers interference. In this case, all of the first to third communication satellites S1 to S3 relay the channel in which the interference has occurred. The switching of the channel relay based on the interference by the interference wave is performed under the control of the control station K.
【００３２】そして、地球局Ｘの信号は第１〜第３通信
衛星Ｓ１〜Ｓ３の全てを経由して管制局Ｋへ到達するこ
ととなり、管制局Ｋでは信号の相関処理により、同じ干
渉信号が「地球局Ｘ→第１通信衛星Ｓ１→管制局Ｋ」と
いう第１経路を経て管制局Ｋに到達するまでに要した時
間と「地球局Ｘ→第２通信衛星Ｓ２→管制局Ｋ」の第２
経路を経て管制局Ｋに到達するまでに要した時間との差
（第１時間差）、並びに「地球局Ｘ→第２通信衛星Ｓ２
→管制局Ｋ」の第２経路を経て管制局Ｋに到達するまで
に要した時間と「地球局Ｘ→第３通信衛星Ｓ３→管制局
Ｋ」の第３経路を経て管制局Ｋに到達するまでに要した
時間との差（第２時間差）を、各々測定する。Then, the signal of the earth station X reaches the control station K via all of the first to third communication satellites S1 to S3, and the control station K generates the same interference signal by correlation processing of the signals. The time required to reach the control station K via the first route of “earth station X → first communication satellite S1 → control station K” and the time required for “earth station X → second communication satellite S2 → control station K” 2
The difference from the time required to reach the control station K via the route (first time difference), and "Earth station X → second communication satellite S2"
→ The time required to reach the control station K via the second route of the control station K and the control station K via the third route of the “earth station X → third communication satellite S3 → control station K”. The difference from the time required until (second time difference) is measured.
【００３３】上記のようにして測定した第１時間差に基
づいて地球局Ｘの存在可能性を示す第１測位曲線を、第
２時間差に基づいて地球局Ｘの存在可能性を示す第２測
位曲線を、各々取得することができる。上述した如く、
第１〜第３通信衛星Ｓ１〜Ｓ３を各々正三角形の頂点に
位置するように配置していることから、等「第１通信衛
星Ｓ１と第２通信衛星Ｓ２とを結ぶ直線の方位」と「第
２通信衛星Ｓ２と第３通信衛星Ｓ２とを結ぶ直線の方
位」とは６０゜の角度を成すので、第１測位曲線Ｌ１と
第２測位曲線Ｌ２も６０゜に近い角度をもって交わるこ
ととなり、干渉波の発信源である地球局Ｘの位置を示す
第１測位曲線と第２測位曲線との交点を明確に特定でき
るのである。しかも、第１測位曲線と第２測位曲線とを
取得するために、数時間の経過を待って再度測定する必
要がないので、即時に地球局Ｘの位置決定を行うことが
できる。The first positioning curve showing the existence possibility of the earth station X based on the first time difference measured as described above, and the second positioning curve showing the existence possibility of the earth station X based on the second time difference. Can be obtained respectively. As mentioned above,
Since the first to third communication satellites S1 to S3 are arranged so as to be located at the vertices of an equilateral triangle, respectively, the "direction of a straight line connecting the first communication satellite S1 and the second communication satellite S2" and " Since the azimuth of the line connecting the second communication satellite S2 and the third communication satellite S2 "forms an angle of 60 °, the first positioning curve L1 and the second positioning curve L2 also cross at an angle close to 60 °, The intersection of the first positioning curve and the second positioning curve indicating the position of the earth station X which is the source of the interference wave can be clearly specified. In addition, since it is not necessary to wait for several hours to measure again in order to acquire the first positioning curve and the second positioning curve, the position of the earth station X can be immediately determined.
【００３４】なお、上記実施形態においては、第１通信
衛星Ｓ１と第２通信衛星Ｓ２を第１ペア通信衛星として
第１測位曲線を取得し、第２通信衛星Ｓ２と第３通信衛
星Ｓ３を第２ペア通信衛星として第２測位曲線を取得す
るものとしたが、第３通信衛星と第１通信衛星をペア通
信衛星の一つとして測位曲線を取得するようにしても良
い。また、測位曲線の取得対象となる第１ペア通信衛星
と第２ペア通信衛星とを予め定めておき、これらのペア
通信衛星を構成する各通信衛星を結ぶ直線の各方位が直
交するように配置すれば、第１測位曲線と第２測位曲線
が９０゜に近い角度で交わるようにすることができる。
さらに、正円軌道上に配置する通信衛星の数は３機に限
らず、４機以上として、何れかの通信衛星に支障が生じ
た場合でも、ペア通信衛星の代替が可能なようにしても
よい。In the above embodiment, the first communication satellite S1 and the second communication satellite S2 are used as the first pair communication satellite to obtain the first positioning curve, and the second communication satellite S2 and the third communication satellite S3 are used as the first communication satellite. Although the second positioning curve is obtained as a two-pair communication satellite, the positioning curve may be obtained using the third communication satellite and the first communication satellite as one of the pair communication satellites. In addition, a first pair communication satellite and a second pair communication satellite from which a positioning curve is to be acquired are determined in advance, and are arranged such that the directions of straight lines connecting the communication satellites constituting the pair communication satellite are orthogonal to each other. Then, the first positioning curve and the second positioning curve can intersect at an angle close to 90 °.
Further, the number of communication satellites arranged in a perfect circular orbit is not limited to three, but may be four or more, so that even if any communication satellite is disturbed, a pair communication satellite can be replaced. Good.
【００３５】[0035]
【発明の効果】以上説明したように、本発明に係る静止
衛星による送信局位置特定方法によれば、送信局の位置
特定を容易に行うことができるので、衛星通信の円滑な
運用を阻害する干渉波を送信する干渉局が存在した場合
には、干渉局の位置を簡便に特定することが可能とな
り、干渉に対する対策を迅速に行うことができ、衛星通
信システム自体の信頼性を高めることに寄与できる。As described above, according to the method of locating a transmitting station by a geostationary satellite according to the present invention, the position of the transmitting station can be easily specified, which hinders a smooth operation of satellite communication. If there is an interfering station that transmits the interfering wave, it is possible to easily specify the position of the interfering station, to quickly take measures against the interference, and to improve the reliability of the satellite communication system itself. Can contribute.
【図１】静止衛星保持領域内に２機の通信衛星を配して
行う送信位置特定方法の概念図である。FIG. 1 is a conceptual diagram of a transmission position identifying method performed by arranging two communication satellites in a geostationary satellite holding area.
【図２】図１の静止衛星保持領域内における通信衛星の
配置状態を示す概略配置図である。FIG. 2 is a schematic arrangement diagram showing an arrangement state of communication satellites in a geostationary satellite holding area of FIG.
【図３】図２の衛星配置で異なる時間に取得した測位曲
線の例示図である。FIG. 3 is a view showing an example of positioning curves obtained at different times in the satellite constellation of FIG. 2;
【図４】静止衛星保持領域内に３機の通信衛星を配して
行う送信位置特定方法の概念図である。FIG. 4 is a conceptual diagram of a transmission position specifying method performed by arranging three communication satellites in a geostationary satellite holding area.
【図５】図４の静止衛星保持領域内における通信衛星の
配置状態を示す概略配置図である。5 is a schematic layout diagram showing an arrangement state of communication satellites in a geostationary satellite holding area in FIG. 4;
【図６】２機の通信衛星で行う従来の送信位置特定方法
の概念図である。FIG. 6 is a conceptual diagram of a conventional transmission position identification method performed by two communication satellites.
【図７】図６の衛星配置で異なる時間に取得した測位曲
線の例示図である。FIG. 7 is a view showing an example of positioning curves obtained at different times in the satellite constellation of FIG. 6;
Ａ 静止衛星保持領域 Ｂ 静止衛星保持領域 Ｓ１ 第１通信衛星 Ｓ２ 第２通信衛星 Ｓ３ 第３通信衛星 Ｘ 地球局 Ｋ 管制局 Ｌ１ 第１測位曲線 Ｌ２ 第２測位曲線 A geostationary satellite holding area B geostationary satellite holding area S1 first communication satellite S2 second communication satellite S3 third communication satellite X earth station K control station L1 first positioning curve L2 second positioning curve
Claims (4)
内に２機の通信衛星を配し、これら２機の通信衛星は夫
々同じチャンネルの電波を中継可能であると共に、両通
信衛星を結ぶ直線の方位が計時的に変化するものとし、
送信局から送信された電波が各通信衛星に到達するまで
の時間差に基づいて地表面上における送信局の存在可能
性を示す測位曲線を複数取得し、取得した複数の測位曲
線の交点を以て送信局の位置を特定するようにしたこと
を特徴とする静止衛星による送信局位置特定方法。1. Two communication satellites are arranged in a geostationary position holding area recognized as a geostationary satellite, and these two communication satellites can respectively relay radio waves of the same channel and have a straight line connecting the two communication satellites. Direction changes in time,
Based on the time difference until the radio waves transmitted from the transmitting station reach each communication satellite, multiple positioning curves indicating the existence possibility of the transmitting station on the ground surface are acquired, and the transmitting station is determined by the intersection of the acquired positioning curves. A method for identifying the position of a transmitting station using a geostationary satellite, characterized in that the position of the satellite is specified.
ながら等速円運動を行うものとしたことを特徴とする請
求項１に記載の静止衛星による送信局位置特定方法。2. The method according to claim 1, wherein the two communication satellites perform a constant-velocity circular motion while maintaining the same distance from each other.
内に３機以上の通信衛星を配し、各通信衛星は夫々同じ
チャンネルの電波を中継可能であると共に、通信衛星群
中の２機で構成するペア通信衛星を結ぶ直線の方位が他
のペア通信衛星を結ぶ直線の方位と交差するように配置
し、送信局から送信された電波が各ペア通信衛星の各通
信衛星に到達する時間差に基づいて地表面上における送
信局の存在可能性を示す測位曲線をペア通信衛星毎に取
得し、取得した複数の測位曲線の交点を以て送信局の位
置を特定するようにしたことを特徴とする静止衛星によ
る送信局位置特定方法。3. Three or more communication satellites are arranged in a stationary position holding area recognized as a geostationary satellite. Each communication satellite can relay radio waves of the same channel, and two or more satellites in the group of communication satellites. Arrange so that the direction of the straight line connecting the pair communication satellites that composes intersects the direction of the straight line connecting the other pair communication satellites. A positioning curve indicating the possibility of the transmitting station on the ground surface is acquired for each pair of communication satellites based on the ground surface, and the position of the transmitting station is specified based on the intersection of the obtained plurality of positioning curves. Transmitter station location method by satellite.
ながら等速円運動を行うものとしたことを特徴とする請
求項３に記載の静止衛星による送信局位置特定方法。4. The method according to claim 3, wherein all communication satellites perform a constant-velocity circular motion while maintaining the same distance from each other.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30502495A JP2739894B2 (en) | 1995-10-30 | 1995-10-30 | Transmitter station location method using geostationary satellites |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30502495A JP2739894B2 (en) | 1995-10-30 | 1995-10-30 | Transmitter station location method using geostationary satellites |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH09127229A true JPH09127229A (en) | 1997-05-16 |
| JP2739894B2 JP2739894B2 (en) | 1998-04-15 |
Family
ID=17940179
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP30502495A Expired - Lifetime JP2739894B2 (en) | 1995-10-30 | 1995-10-30 | Transmitter station location method using geostationary satellites |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2739894B2 (en) |
Cited By (6)
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|---|---|---|---|---|
| JP2007088612A (en) * | 2005-09-20 | 2007-04-05 | Mitsubishi Electric Corp | Communication satellite, manufacturing method thereof, and earth station |
| JP2009250865A (en) * | 2008-04-09 | 2009-10-29 | Mitsubishi Electric Corp | Positioning system and positioning method |
| JP2013029419A (en) * | 2011-07-28 | 2013-02-07 | Mitsubishi Electric Corp | Positioning device |
| JP2015184276A (en) * | 2014-03-21 | 2015-10-22 | ザ・ボーイング・カンパニーＴｈｅＢｏｅｉｎｇ Ｃｏｍｐａｎｙ | Interference geolocation using satellite constellation |
| JP2016511719A (en) * | 2012-12-05 | 2016-04-21 | エスエーエス・エス・ア | Apparatus, system, and method for obtaining information about electromagnetic energy from the earth, eg, for searching for interference sources on the earth |
| US10720986B2 (en) | 2012-12-05 | 2020-07-21 | Ses S.A. | Apparatuses, systems and methods for obtaining information about electromagnetic energy emitted from the earth, such as for locating an interference source on earth |
-
1995
- 1995-10-30 JP JP30502495A patent/JP2739894B2/en not_active Expired - Lifetime
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007088612A (en) * | 2005-09-20 | 2007-04-05 | Mitsubishi Electric Corp | Communication satellite, manufacturing method thereof, and earth station |
| JP2009250865A (en) * | 2008-04-09 | 2009-10-29 | Mitsubishi Electric Corp | Positioning system and positioning method |
| JP2013029419A (en) * | 2011-07-28 | 2013-02-07 | Mitsubishi Electric Corp | Positioning device |
| JP2016511719A (en) * | 2012-12-05 | 2016-04-21 | エスエーエス・エス・ア | Apparatus, system, and method for obtaining information about electromagnetic energy from the earth, eg, for searching for interference sources on the earth |
| US9985719B2 (en) | 2012-12-05 | 2018-05-29 | Ses S.A. | Apparatuses, systems and methods for obtaining information about electromagnetic energy emitted from the earth, such as for locating an interference source on earth |
| US10720986B2 (en) | 2012-12-05 | 2020-07-21 | Ses S.A. | Apparatuses, systems and methods for obtaining information about electromagnetic energy emitted from the earth, such as for locating an interference source on earth |
| JP2015184276A (en) * | 2014-03-21 | 2015-10-22 | ザ・ボーイング・カンパニーＴｈｅＢｏｅｉｎｇ Ｃｏｍｐａｎｙ | Interference geolocation using satellite constellation |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2739894B2 (en) | 1998-04-15 |
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