JPH0357325A - Earth station communication equipment - Google Patents
Earth station communication equipmentInfo
- Publication number
- JPH0357325A JPH0357325A JP19368389A JP19368389A JPH0357325A JP H0357325 A JPH0357325 A JP H0357325A JP 19368389 A JP19368389 A JP 19368389A JP 19368389 A JP19368389 A JP 19368389A JP H0357325 A JPH0357325 A JP H0357325A
- Authority
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- Japan
- Prior art keywords
- frequency
- attained
- circuit
- earth station
- receiving
- Prior art date
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- Granted
Links
- 238000004891 communication Methods 0.000 title claims description 37
- 230000005540 biological transmission Effects 0.000 claims abstract description 25
- 238000000926 separation method Methods 0.000 abstract description 5
- 238000000034 method Methods 0.000 description 7
- 238000010586 diagram Methods 0.000 description 4
- 238000001514 detection method Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000000969 carrier Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
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Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、衛星通信の地球局通信装置に利用する。特に
、複数のチャネルを周波数多重して通信衛星を介して複
数の地球局と通信を行うscpc方式(Single
Channel Per Carrier方式)の地球
局通信装置に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is applied to an earth station communication device for satellite communication. In particular, the SCPC method (Single
The present invention relates to an earth station communication device based on the Channel Per Carrier method.
本発明は地球局通信装置において、
所定の周期で短時間の無変調キャリヤを送信し、通信衛
星で折返された無変調キャリヤと送信した無変調キャリ
ヤとの周波数を比較し、この比較結果に基づき受信側周
波数を補正することにより、規模が小さく安価でチャネ
ル効率が良く、かつ良好なチャネル分離ができるように
したものである。The present invention uses an earth station communication device to transmit a short-time unmodulated carrier at a predetermined period, compare the frequencies of the unmodulated carrier returned by the communication satellite and the transmitted unmodulated carrier, and based on the comparison result, By correcting the frequency on the receiving side, it is possible to achieve small scale, low cost, high channel efficiency, and good channel separation.
従来、地球局通信装置は、周波数変換器やフィルタを用
いてチャネルの分離を行っていた。このために、チャネ
ルの帯域に比べて無線周波数が極めて大きな場合には、
周波数変換器等は極めて高い周波数精度が要求される。Conventionally, earth station communication equipment has used frequency converters and filters to separate channels. For this reason, when the radio frequency is extremely large compared to the channel band,
Frequency converters and the like require extremely high frequency accuracy.
この要求を満たすために、従来種々のAFC方式(Au
tomatic Frequen−cy CoITIp
ensation方式)が用いられてきた。In order to meet this demand, various AFC methods (Au
tomatic Frequency CoITIp
ensation method) has been used.
一例としてパイロットキャリヤを用いる方法がある。こ
れは多数チャネルのうち特定チャネルに無変調キャリヤ
を送出し、送出局以外の局はその無変調キャリヤを周波
数基準とする方式である。One example is a method using a pilot carrier. This is a system in which a non-modulated carrier is sent to a specific channel among a large number of channels, and stations other than the sending station use the non-modulated carrier as a frequency reference.
特に、衛星通信では、衛星トランスボンダの周波数変動
や衛星自体のドップラ効果による周波数変動が大きく、
回線全体の周波数安定度を所要の値に抑えるためには、
パイロットキャリヤ方式が必要不可欠なものとなってい
た。In particular, in satellite communications, there are large frequency fluctuations due to frequency fluctuations of the satellite transbonder and the Doppler effect of the satellite itself.
In order to suppress the frequency stability of the entire line to the required value,
The pilot carrier system had become indispensable.
「発明が解決しようとする問題点〕
しかし、このような従来の地球局通信装置では、パイロ
ットキャリヤを用いるAFC方式であるために、パイロ
ットキャリヤ専用の送信装置および受信装置が必要で装
置規模が大きく、小容量の通信局ではその占める比率は
無視できずまた高価な欠点があった。"Problems to be Solved by the Invention" However, since such conventional earth station communication equipment uses an AFC method that uses a pilot carrier, it requires a transmitter and a receiver dedicated to the pilot carrier, resulting in a large equipment scale. However, in small-capacity communication stations, their proportion could not be ignored, and they also had the disadvantage of being expensive.
また、パイロットキャリヤのために周波数帯域を通常1
チャネル分占有することになり、本来の通信に用いるチ
ャネル数が減少する欠点があった。Also, one frequency band is usually allocated for the pilot carrier.
This has the disadvantage that the number of channels used for actual communication is reduced because the number of channels is occupied.
本発明は上記の欠点を解決するもので、規模が小さく安
価でチャネル効率が良く、かつ良好なチャネル分離がで
きる地球局通信装置を提供することを目的とする。The present invention solves the above-mentioned drawbacks, and aims to provide an earth station communication device that is small in scale, inexpensive, has good channel efficiency, and can perform good channel separation.
本発明は、入力する送信ベースバンド信号に基づいて複
数のチャネルのそれぞれの周波数を変調する変調手段と
、この変調手段の出力信号を通信衛星に送信する送信手
段と、この通信衛星の出力信号を受信する受信手段と、
この受信手段の出力信号を上記各チャネルごとに復調し
て受信ベースバンド信号を出力する復調手役と、上記変
調手段およびこの復調手段の周波数分割制御を行う周波
数制御手段とを備えた地球局通信装置において、上記周
波数制御手段は、所定の周期で短時間上記送信ベースバ
ンド信号を上記変調手段に与えることを中断してその期
間に無変調キャリヤを送出させる手段と、この送出され
た無変調キャリヤが上記通信衛星により折返された信号
を上記復調手段から入力しその信号の周波数変動を検出
する手段と、この検出する手段の検出結果に基づいて上
記受信手段の出力周波数の制御を行う手段とを含むこと
を特徴とする。The present invention provides a modulation means for modulating the frequency of each of a plurality of channels based on an input transmission baseband signal, a transmission means for transmitting an output signal of the modulation means to a communication satellite, and a transmission means for transmitting an output signal of the communication satellite. a receiving means for receiving;
Earth station communication comprising a demodulator for demodulating the output signal of the receiving means for each channel and outputting a received baseband signal, and a frequency control means for frequency division control of the modulating means and the demodulating means. In the apparatus, the frequency control means includes means for interrupting the application of the transmission baseband signal to the modulation means for a short period of time at a predetermined period and transmitting an unmodulated carrier during the period; means for inputting a signal returned by the communication satellite from the demodulating means and detecting the frequency fluctuation of the signal; and means for controlling the output frequency of the receiving means based on the detection result of the detecting means. It is characterized by containing.
周波数制御手段は所定の周期で短時間送信ベースバンド
信号を変調手段に与えることを中断してその期間に無変
調キャリヤを送出させる。またこの送出された無変調キ
ャリヤが通信衛星を介して折返された信号を復調手段か
ら人力しその信号と送出したときの無変調キャリヤとの
周波数を比較して周波数変動を検出する。さらにこの検
田結果に基づいて次の無変調キャリヤを送出するまでの
期間受信手段の出力周波数を制御する。以上の動作によ
り規模が小さく安価でチャネル効率が良く、かつ良好な
チャネル分離ができる。The frequency control means interrupts supplying the transmission baseband signal to the modulation means for a short time at a predetermined period, and causes the unmodulated carrier to be transmitted during that period. Further, a signal obtained by returning the transmitted non-modulated carrier via a communication satellite is manually inputted from a demodulating means, and the frequency of the signal is compared with that of the transmitted non-modulated carrier to detect frequency fluctuations. Furthermore, based on the result of this field detection, the output frequency of the receiving means is controlled for a period until the next non-modulated carrier is sent out. The above operation makes it possible to achieve small scale, low cost, high channel efficiency, and good channel separation.
本発明の実施例について図面を参照して説明する。第1
図は本発明一実施例地球局通信装置のブロック構成図で
ある。第1図において、地球局通信装置は、入力する送
信ベースバンド信号に基づいて複数のチャネルのそれぞ
れの周波数を変調する変調手段として送信側シンセサイ
ヂ回路6および変調器7と、この変調器7の出力信号を
通信衛星に送信する送信手段として送信周波数変換器3
、フィーダ回路2の一部およびアンテナiの一部と、こ
の通信衛星の出力信号を受信する受信手段としてアンテ
ナ1の一部、フィーダ回路2の一部および受信周波数変
換器4と、受信周波数変換器4の出力信号を上記各チャ
ネルごとに復調して受信ベースバンド信号を出力する復
調手役として受信側シンセサイザ回路9および復調器8
と、変調器7および復調器8の周波数分割制御を行う周
波数制御手段として周波数制御回路l1の一部とを備え
る。Embodiments of the present invention will be described with reference to the drawings. 1st
The figure is a block diagram of an earth station communication device according to an embodiment of the present invention. In FIG. 1, the earth station communication device includes a transmitting side synthesis circuit 6 and a modulator 7 as modulating means for modulating the frequencies of each of a plurality of channels based on an input transmitting baseband signal, and an output of the modulator 7. Transmission frequency converter 3 as a transmission means for transmitting signals to a communication satellite
, a part of the feeder circuit 2, a part of the antenna i, a part of the antenna 1, a part of the feeder circuit 2, a reception frequency converter 4, and a reception frequency converter as receiving means for receiving the output signal of this communication satellite. A receiving side synthesizer circuit 9 and a demodulator 8 serve as demodulators to demodulate the output signal of the converter 4 for each channel and output a received baseband signal.
and a part of a frequency control circuit l1 as frequency control means for performing frequency division control of the modulator 7 and demodulator 8.
ここで本発明の特徴とするところは、周波数制御手段は
、所定の周期で短時間上記送信ベースバンド信号を変調
器7に与えることを中断してその期間に無変調キャリヤ
を送出させる手段として切替器10および周波数制御回
路11の一部と、この送出された無変調キャリヤが上記
通信衛星により折返された信号を復調器8から入力しそ
の信号の周波数変動を検出する手段として周波数制御回
路11の一部と、この検出する手段の検出結果に基づい
て受信周波数変換器4の出力周波数の制御を行う手段と
して電圧制御発振器5および周波数制御回路11の一部
とを含むことにある。Here, the feature of the present invention is that the frequency control means interrupts supplying the transmission baseband signal to the modulator 7 for a short time at a predetermined period, and switches the frequency control means to transmit an unmodulated carrier during that period. 10 and a part of the frequency control circuit 11, and a part of the frequency control circuit 11 as a means for inputting a signal from the demodulator 8 into which the transmitted non-modulated carrier is reflected by the communication satellite and detecting the frequency fluctuation of the signal. and a part of the voltage controlled oscillator 5 and the frequency control circuit 11 as means for controlling the output frequency of the receiving frequency converter 4 based on the detection result of the detecting means.
このような構或の地球局通信装置の動作について説明す
る。第2図は本発明の地球局通信装置の無変調キャリヤ
の送受信タイミングを示す図である。第1図において、
通信データの送信時には、送信ベースバンド装置より入
力された送信信号は、切替器10を通った後に変調器7
により変調される。The operation of the earth station communication device having such a structure will be explained. FIG. 2 is a diagram showing the transmission and reception timing of an unmodulated carrier in the earth station communication device of the present invention. In Figure 1,
When transmitting communication data, the transmission signal input from the transmission baseband device passes through the switch 10 and then the modulator 7.
Modulated by
次に送信側シンセサイザ回路6により無線チャネルを選
択された後に送信周波数変換器3、フィーダ回路2およ
びアンテナ1を介して通信衛星に送信される。Next, after a radio channel is selected by the transmitting side synthesizer circuit 6, the signal is transmitted to the communication satellite via the transmitting frequency converter 3, the feeder circuit 2, and the antenna 1.
一方、通信データの受信時はアンテナ1とフィーダ回路
2を通った後に受信周波数変換器4を通った後に復調器
8で復調される。ここで、受信チャネルは受信側シンセ
サイザ回路9により選択される。復調器8の出力は受信
ベースバンド装置へ出力される。On the other hand, when receiving communication data, the data passes through the antenna 1 and the feeder circuit 2, passes through the reception frequency converter 4, and is then demodulated by the demodulator 8. Here, the receiving channel is selected by the receiving synthesizer circuit 9. The output of the demodulator 8 is output to the receiving baseband device.
なお本実施例では簡単のため変復調部が1回路のみ示さ
れているが多数の変復調部を周波数変換器に接続し周波
数多重も可能である。In this embodiment, only one modulation/demodulation section is shown for simplicity, but it is also possible to connect multiple modulation/demodulation sections to a frequency converter to perform frequency multiplexing.
一方、本実施例で与えられる周波数制御回路11は、送
信側シンセサイザ回路6および受信側シンセサイザ回路
9の周波数制御を行う手段をもつ。On the other hand, the frequency control circuit 11 provided in this embodiment has means for controlling the frequencies of the transmitting synthesizer circuit 6 and the receiving synthesizer circuit 9.
また、切替器10を制御することにより無変調キャリヤ
を送信する手段をもつ。さらに受信周波数変換器4の出
力信号を入力し、周波数をカウントするカウント手段を
もつ。また上記カウント手段で得られた周波数と本来の
周波数との差分を検出し、それを補償するために電圧制
御発振器5を制御する手段をもつ。It also has means for transmitting unmodulated carriers by controlling the switch 10. Furthermore, it has a counting means for inputting the output signal of the receiving frequency converter 4 and counting the frequency. It also has means for detecting the difference between the frequency obtained by the counting means and the original frequency and controlling the voltage controlled oscillator 5 to compensate for the difference.
次に本発明による自局内折返しによる自動周波数補償の
方法について説明する。周波数制御回路11は所定の周
期毎に切替器10を制御し、強制的に無変調キャリヤを
作る。この無変調キャリヤ送出時間は、短時間でよく、
また周波数制御回路l1のカウント手段がカウントでき
る程度の時間で良い。Next, a method of automatic frequency compensation by loopback within the local station according to the present invention will be explained. The frequency control circuit 11 controls the switch 10 at predetermined intervals to forcibly create a non-modulated carrier. This unmodulated carrier sending time may be short,
Further, the time may be long enough to be counted by the counting means of the frequency control circuit l1.
また、無変調キャリヤの送出周期は、周波数変動の支配
的要素が通信衛星および送受信周波数変換器でありそれ
らが短期的変動よりは長期的変動である点を考慮し、た
とえば1時間周期程度の長時間に選択される。In addition, the transmission period of the unmodulated carrier should be set to a period of about one hour, for example, considering that the dominant elements of frequency fluctuation are communication satellites and transmitting/receiving frequency converters, and these fluctuations are long-term rather than short-term fluctuations. selected at the time.
次に、自局折返しによる周波数補正は第2図に示すタイ
ミングにて行われる。第2図(a)において、Txは無
変調キャリヤ退出時間を示す。無変調キャリヤを受信す
るため受信側シンセサイザ回路9を送信側と同一チャネ
ルに切換えるがそのタイミングを示したものが第2図ら
)である。すなわち、通信衛星による遅延時間TIll
分だけ遅らせた後に無変調キャリヤ送出時間T1の時間
のみ送受同一チャネルとなっている。無変調キャリヤの
受信時には、瞬時に周波数制御回路11のカウント手段
のゲートが開き、周波数をカウントし、その結果本来の
周波数との比較によりその周波数差分に相当する電圧を
電圧制御発振器5に与える。Next, frequency correction by local station loopback is performed at the timing shown in FIG. In FIG. 2(a), Tx indicates the unmodulated carrier exit time. In order to receive an unmodulated carrier, the receiving side synthesizer circuit 9 is switched to the same channel as the transmitting side, and the timing thereof is shown in FIGS. In other words, the delay time TIll due to the communication satellite
After a delay of 1 minute, the same channel is used for transmission and reception only during the non-modulated carrier transmission time T1. When a non-modulated carrier is received, the gate of the counting means of the frequency control circuit 11 is instantaneously opened, the frequency is counted, and as a result, a voltage corresponding to the frequency difference is applied to the voltage controlled oscillator 5 by comparison with the original frequency.
以上で自局内周波数補正が完了し、完了と同時に通常の
データ送受信状態となる。この場合に電圧制御発振器5
の制御電圧は、周波数制御回路l1によって記憶され次
の周波数補正時まで同一制御電圧を使用する。With the above steps, the internal frequency correction is completed, and at the same time, the normal data transmission/reception state is established. In this case, the voltage controlled oscillator 5
The control voltage is stored by the frequency control circuit l1, and the same control voltage is used until the next frequency correction.
上述した自局内周波数補正を各地球局が行うことにより
衛星トランスポンダの周波数変動や受信系高周波回路の
周波数変動を抑えることができる。By each earth station performing the above-described internal frequency correction, it is possible to suppress frequency fluctuations in the satellite transponder and in the receiving system high frequency circuit.
なお本実施例は自局折返しによる周波数補正を行ってい
るために各地球局間の通信では各送信系が自局折返し時
と異なるため周波数補正されないことになる。このため
に各地球局の送信側高周波回路すなわち送信周波数変換
器3の周波数偏差を少なくして各地球局間の周波数誤差
をなくすことが必要である。Note that in this embodiment, since frequency correction is performed by returning to the own station, in communication between each earth station, each transmission system is different from when returning to the own station, so frequency correction is not performed. For this purpose, it is necessary to reduce the frequency deviation of the transmitting side high frequency circuit of each earth station, that is, the transmission frequency converter 3, and eliminate the frequency error between each earth station.
以上説明したように、本発明は、高価なパイロットキャ
リヤ方式を使用せず規模が小さく安価な制御回路で正確
な受信ができる優れた高価がある。As described above, the present invention is advantageous in that it does not use an expensive pilot carrier system and can perform accurate reception with a small scale and inexpensive control circuit.
また電圧制御発振器を高い周波数精度で制御することが
不必要な利点がある。Another advantage is that it is not necessary to control the voltage controlled oscillator with high frequency accuracy.
第1図は本発明一実施例地球局通信装置のブロック構戊
図。
第2図は本発明の地球局通信装置の無変調キャリヤの送
受信タイミングを示す図。
l・・・アンテナ、2・・・フィーダ回路、3・・・送
信周波数変換器、4・・・受信周波数変換器、5・・・
電圧制御発振器、6・・・送信側シンセサイザ回路、7
・・・変調器、8・・・復調器、9・・・受信側シンセ
サイザ回路、10・・・切替器、l1・・・周波数制御
回路。
実施例
無変調キャソヤの送受信タイミング
第
2
図FIG. 1 is a block diagram of an earth station communication device according to an embodiment of the present invention. FIG. 2 is a diagram showing the transmission and reception timing of an unmodulated carrier in the earth station communication device of the present invention. l...Antenna, 2...Feeder circuit, 3...Transmission frequency converter, 4...Reception frequency converter, 5...
Voltage controlled oscillator, 6... Transmission side synthesizer circuit, 7
... Modulator, 8 ... Demodulator, 9 ... Receiving side synthesizer circuit, 10 ... Switch, l1 ... Frequency control circuit. Embodiment: Transmission and reception timing of non-modulated CASSOYA Figure 2
Claims (1)
ャネルのそれぞれの周波数を変調する変調手段と、この
変調手段の出力信号を通信衛星に送信する送信手段と、
この通信衛星の出力信号を受信する受信手段と、この受
信手段の出力信号を上記各チャネルごとに復調して受信
ベースバンド信号を出力する復調手段と、上記変調手段
およびこの復調手段の周波数分割制御を行う周波数制御
手段とを備えた 地球局通信装置において、 上記周波数制御手段は、所定の周期で短時間上記送信ベ
ースバンド信号を上記変調手段に与えることを中断して
その期間に無変調キャリヤを送出させる手段と、この送
出された無変調キャリヤが上記通信衛星により折返され
た信号を上記復調手段から入力しその信号の周波数変動
を検出する手段と、この検出する手段の検出結果に基づ
いて上記受信手段の出力周波数の制御を行う手段とを含
む ことを特徴とする地球局通信装置。[Claims] 1. A modulating means for modulating the frequency of each of a plurality of channels based on an input transmission baseband signal, and a transmitting means for transmitting an output signal of the modulating means to a communication satellite;
A receiving means for receiving the output signal of the communication satellite, a demodulating means for demodulating the output signal of the receiving means for each channel and outputting a received baseband signal, and frequency division control of the modulating means and the demodulating means. In the earth station communication device, the frequency control means interrupts providing the transmission baseband signal to the modulation means for a short time at a predetermined period, and transmits the unmodulated carrier during that period. means for transmitting the unmodulated carrier, a means for inputting a signal obtained by returning the transmitted unmodulated carrier by the communication satellite from the demodulating means and detecting the frequency fluctuation of the signal; An earth station communication device comprising: means for controlling the output frequency of the receiving means.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP19368389A JPH0728255B2 (en) | 1989-07-25 | 1989-07-25 | Earth station communication equipment |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP19368389A JPH0728255B2 (en) | 1989-07-25 | 1989-07-25 | Earth station communication equipment |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH0357325A true JPH0357325A (en) | 1991-03-12 |
JPH0728255B2 JPH0728255B2 (en) | 1995-03-29 |
Family
ID=16312052
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP19368389A Expired - Lifetime JPH0728255B2 (en) | 1989-07-25 | 1989-07-25 | Earth station communication equipment |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH0728255B2 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2010141380A (en) * | 2008-12-09 | 2010-06-24 | Panasonic Electric Works Co Ltd | Radio transmitter, and radio communication system |
-
1989
- 1989-07-25 JP JP19368389A patent/JPH0728255B2/en not_active Expired - Lifetime
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2010141380A (en) * | 2008-12-09 | 2010-06-24 | Panasonic Electric Works Co Ltd | Radio transmitter, and radio communication system |
Also Published As
Publication number | Publication date |
---|---|
JPH0728255B2 (en) | 1995-03-29 |
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