JPS609231A - Correcting system for gain variance of satellite repeater - Google Patents
Correcting system for gain variance of satellite repeaterInfo
- Publication number
- JPS609231A JPS609231A JP11506783A JP11506783A JPS609231A JP S609231 A JPS609231 A JP S609231A JP 11506783 A JP11506783 A JP 11506783A JP 11506783 A JP11506783 A JP 11506783A JP S609231 A JPS609231 A JP S609231A
- Authority
- JP
- Japan
- Prior art keywords
- level
- satellite
- signal wave
- gain
- repeater
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/005—Control of transmission; Equalising
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Radio Relay Systems (AREA)
Abstract
Description
【発明の詳細な説明】
（技術分野）
本発明は例えばＦＤＭＡ方式に適用される衛星通信方式
における衛星中継器利得の変動を補正する方法に関する
ものである。DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a method for correcting variations in satellite repeater gain in a satellite communication system applied to, for example, an FDMA system.
（背景技術）
ＰＤＭＡ衛星通信方式では衛星中継器の利得が変動する
と次に示すような劣化が生じる。すなわち、衛星中継器
利得がΔＧｄＢ増加すると衛星送信出力増幅器の動作点
がΔＧｄＢ増加し混変調雑音の発生が大きくなること、
また衛星中継器利得がΔＧｄＰ！減少すると衛星送信出
力がΔＧｄＢＧｄ上、地球局受信の信号電力対雑力電力
比が低下することである。このため、この衛星中継器の
利得変動を小さく抑圧することが必要となる。(Background Art) In the PDMA satellite communication system, when the gain of the satellite repeater changes, the following deterioration occurs. In other words, when the satellite repeater gain increases by ΔGdB, the operating point of the satellite transmission output amplifier increases by ΔGdB, which increases the generation of cross-modulation noise.
Also, the satellite repeater gain is ΔGdP! When it decreases, the satellite transmission output increases by ΔGdBGd, and the signal power to noise power ratio of the earth station reception decreases. Therefore, it is necessary to suppress the gain fluctuation of this satellite repeater to a small level.
この種の方法について、従来提案されている方法に次の
２つが知られている。Regarding this type of method, the following two methods are known as conventionally proposed methods.
（１）方法Ｉ：複数の地球局のうちのある一局がある特
定の信号波を衛星に向けて送信し、衛星からのその折返
し信号波の受信レベルを検出し、この検出結果にもとづ
いて衛星中継器の利得を制御する方法である。本方法で
は受信信号波のレベルを常に該当地球局で監視する必要
があり、また衛星中継器の利得を制御するために地球局
から衛星に向けてコマンド信号を送出しなければならな
い欠点がある。(1) Method I: One of the multiple earth stations transmits a specific signal wave toward the satellite, detects the reception level of the returned signal wave from the satellite, and based on this detection result, This is a method of controlling the gain of a satellite repeater. This method has the disadvantage that the level of the received signal wave must be constantly monitored at the relevant earth station, and that a command signal must be sent from the earth station to the satellite in order to control the gain of the satellite repeater.
（２）方法■：ある地球局からある特定の信号波を衛星
に向けて送信し、衛星上でその信号波の衛星出力の絶対
レベル値を検出し、この検出結果にもとづいて衛星中継
器の利得を制御する方法である。(2) Method■: A certain earth station transmits a certain signal wave toward a satellite, the absolute level value of the satellite output of that signal wave is detected on the satellite, and based on this detection result, the satellite repeater This is a method of controlling gain.
一般に衛星中継器の周囲温度は蝕の影響もあり一１０°
Ｃから＋４０’Ｃの変化が予想される。このため、本方
法ではこのような広範囲な温度変化に対して信号波の絶
対レベルを簡易な検出器で精度高く検出することが難し
い欠点がある。Generally, the ambient temperature of a satellite repeater is -10° due to the influence of eclipses.
A change of +40'C is expected. For this reason, this method has the disadvantage that it is difficult to accurately detect the absolute level of the signal wave with a simple detector over such a wide range of temperature changes.
（発明の課題）
本発明はこれらの欠点を除去するため、衛星送信出力レ
ベルが一定となるように地球局でレベル制御されたある
特定の信号波と、地球局で送信レベルが制御されていな
いある特定の信号波の２つの信号波の相対レベル差を衛
星上において検出し、この検出結果にもとづいて衛星中
継器の利得を制御させるもので、以下図面について詳細
に説明する。(Problems to be solved by the invention) In order to eliminate these drawbacks, the present invention uses a certain signal wave whose level is controlled at the earth station so that the satellite transmission output level is constant, and a signal wave whose transmission level is not controlled at the earth station. The relative level difference between two specific signal waves is detected on the satellite, and the gain of the satellite repeater is controlled based on the detection result.The drawings will be described in detail below.
（発明の構成および作用）
第１図はＦＤＭＡ固定局衛星通信方式を対象とした場合
の本発明の実施例であり、第２図は第１図の地球局１の
構成図を示したものである。(Structure and operation of the invention) FIG. 1 shows an embodiment of the present invention targeting an FDMA fixed station satellite communication system, and FIG. 2 shows a configuration diagram of the earth station 1 in FIG. 1. be.
最初に第１図の地球局１（以下、地球局Ａと呼ぶ）、地
球局２（以下、地球局Ｂと呼ぶ）の動作を説明する。First, the operations of earth station 1 (hereinafter referred to as earth station A) and earth station 2 (hereinafter referred to as earth station B) in FIG. 1 will be explained.
第２図において、信号波ｆ八′はアンテナ１３、送受分
波器１４、受信機１５を経由して受信レベル検出器１６
に入力し、その受信レベルが検出される。この検出器１
６の検出結果にもとづいて、信号波ｆＡ′の受信レベル
が常に一定となるように信号波生成回路１９の出力に接
続されている可変減衰器１８を制御する。これにより送
信機１７の出力レベルは衛星中継器の利得変動に起因す
る信号波ｆｉ／の受信レベル変動を補正するように変化
し、常に一定の衛星送信出力レベルの信号波ｆ八′を得
ることができる。第１０の地球局Ｂは地球局Ａのように
送信信号波のレベルを変化する機能は無く、常に一定の
送信レベルで信号波ｆｉ’を送出する地球局である。In FIG. 2, the signal wave f8' passes through the antenna 13, the transmitter/receiver splitter 14, and the receiver 15, and then passes through the reception level detector 16.
input, and its reception level is detected. This detector 1
Based on the detection result of step 6, the variable attenuator 18 connected to the output of the signal wave generation circuit 19 is controlled so that the reception level of the signal wave fA' is always constant. As a result, the output level of the transmitter 17 changes to compensate for fluctuations in the reception level of the signal wave fi/ caused by gain fluctuations of the satellite repeater, and it is possible to obtain a signal wave f8' with a constant satellite transmission output level. I can do it. The tenth earth station B does not have the function of changing the level of the transmitted signal wave like the earth station A, and is an earth station that always transmits the signal wave fi' at a constant transmission level.
つぎに第１図の衛星中継器の動作について説明する。第
１図で地球局ＡおよびＢからの信号波ｆＡ。Next, the operation of the satellite repeater shown in FIG. 1 will be explained. In Figure 1, signal waves fA from earth stations A and B.
ハはアンテナ３、送受分波器５を経由して受信機６に入
力する。いま、入力信号波ｆＡ 、 ｆｉの各々の入力
レベルをＰＡ（ｄＢｍ） 、 ＰＢ（ｄＢｍ）とし、そ
の対応する出力信号波をｆＡζｆＢ′とする。信号波ｆ
梧マ第１図に示されるように、分波器７、固定減衰器９
、分波器１０を経由して送信機１１に入力し、またｆｓ
／（、ま第１図の７．８．１００回路を経由して１１に
入力する。C is input to the receiver 6 via the antenna 3 and the transmitter/receiver duplexer 5. Now, let the input levels of the input signal waves fA and fi be PA (dBm) and PB (dBm), respectively, and let the corresponding output signal waves be fAζfB'. signal wave f
As shown in Fig. 1, a duplexer 7, a fixed attenuator 9
, input to the transmitter 11 via the duplexer 10, and fs
/(, is input to 11 via the 7.8.100 circuit in FIG. 1.
信号波ｆＡＩ、 ｆ’ｓｌの送信機１１の出力レベルを
Ｐｏｕｔａ （ｄＢｍ）。The output level of the transmitter 11 of the signal waves fAI and f'sl is Pouta (dBm).
ＰｏｕｔＢ（ｄＢｍ）とし、第１図の５９．６．７．８
．１ｑ。PoutB (dBm), 59.6.7.8 in Figure 1
．． 1q.
１１の回路、あるいは５．６．７．９．１０．１１の回
路の総合利得（これを衛星中継器利得と呼ぶ）をＱ （
ｄＢ）とすると次式の関係が成立する。The total gain of the circuit No. 11 or the circuit No. 5.6.7.9.10.11 (this is called the satellite repeater gain) is Q (
dB), the following relationship holds true.
ＰｏｕｔＡ＝Ｇ＋ＰＡ、Ｐｏｕｔｎ＝Ｇ＋ＰＢ −・−
・・・（１）ここで、説明を簡単にするために衛星中継
器利得Ｑ （ｄＢ）のときＰＡとＰＢが等しく、減衰器
８と９の減衰量が同一であるとする。このとき、相対レ
ベル差検出器１２には同一レベルの信号波ｆ八′とｆＢ
′が入力し、その出力は零となる。（ただしＰＡとＰＢ
が等しくないとき、又は減衰器８と９の利得変動がない
ときの減衰量が等しくないときは、相対レベル差検出器
１２の出力は両者の差に従った値になる）。PoutA=G+PA, Poutn=G+PB -・-
(1) Here, to simplify the explanation, it is assumed that when the satellite repeater gain Q (dB) is, PA and PB are equal and the attenuation amounts of attenuators 8 and 9 are the same. At this time, the relative level difference detector 12 detects signal waves f8' and fB of the same level.
′ is input, and its output is zero. (However, PA and PB
(If the attenuation amounts of the attenuators 8 and 9 are not equal when there is no gain variation, the output of the relative level difference detector 12 will be a value according to the difference between the two).
しかし、衛星中継器利得がＧ（ｄＢ）からＧ＋ΔＧ（ｄ
Ｂ）に変化した場合、信号波ｆＡ′とハ′の送信機１１
の出力Ｐｏｕｔ’Ａ、 Ｐｏｕｔ′Ｂｋま各々次式のよ
うになる。However, the satellite repeater gain changes from G(dB) to G+ΔG(d
B), the transmitter 11 of the signal waves fA' and H'
The outputs Pout'A and Pout'Bk are as shown in the following equations.
Ｐｏｕｔ′Ａ＝Ｇ十ΔＧ十ＰＡ’＝Ｇ十ＰＡ ＝Ｐｏｕ
ｔＡ ｒＰ ｏｕ ｔ’ｎ ＝ Ｑ十ΔＱ＋ｐＢ＝Ｐｏ
ｕｔＢ＋ΔＧ・・・・・・（２）ただし、ＰＡ／は衛星
中継器利得Ｇ＋ΔＧにおける受信機６での入力レベルで
あり、先の地球局Ａでの動作説明よりＰＡ′＝Ｐ八−Δ
Ｇとなる。Pout'A=G0ΔG0PA'=G0PA=Pou
tA rP out t'n = Q0ΔQ+pB=Po
utB + ΔG (2) However, PA/ is the input level at the receiver 6 at the satellite repeater gain G + ΔG, and from the previous explanation of the operation at earth station A, PA' = P8 - Δ
It becomes G.
したがって、式（２）より相対レベル検出器１２の出力
はΔＧ（ｄＢ）となる。この検出器１２の出力により可
変減衰器８の減衰量をΔＧ（ｄＢ）増加させることによ
り、第１図の５．６．７．８．１０．１１の回路の衛星
中継器利得を再びＧ（ｄＢ）にすることができ、中継器
利得変動が補正されたことになる。本方法によれば衛星
中継器利得の設定精度は、相対レベル差検出器１２の精
度で決定される。相対的なレベル差は絶対値を検出する
のに比較して高精度が得られるため、この結果利得設定
精度は高いものが得られる特長がある。Therefore, from equation (2), the output of the relative level detector 12 is ΔG (dB). By increasing the attenuation of the variable attenuator 8 by ΔG (dB) using the output of this detector 12, the satellite repeater gain of the circuit 5.6.7.8.10.11 in FIG. dB), which means that repeater gain fluctuations have been corrected. According to this method, the accuracy of setting the satellite transponder gain is determined by the accuracy of the relative level difference detector 12. Since higher accuracy can be obtained by detecting a relative level difference than by detecting an absolute value, this method has the advantage that high gain setting accuracy can be obtained as a result.
第３図はＦＤＭＡ移動衛星通信方式を対象とじた本発明
の実施例である。移動衛星通信方式では基地局・衛星間
の通信に割り当てられる周波数と移動局・衛星間の通信
に割り当てられる周波数とが異なる。このため、第３図
に示す衛星中継器では受信機２７．２９、送信機２８、
蜀が必要となり、さらに移動局相互間の通信を行うため
の周波数変換器３１が必要となる。以下では移動局相互
間を接続する衛星中継器の利得変動を補、正する場合に
ついて説明する。第３図の基地局２１では信号波ｆｈを
衛星に向けて送信する。この信号波ｆｈは衛星アンテナ
お、送受分波器５、受信機２７、送信機３０、送受分波
器あ、衛星アンテナ冴を経由して信号波ｆ八′となって
擬似移動局で受信される。ここで、擬似移動局とは基地
局に隣接して設置され、移動局のアンテナ、送受分波器
、送受信機を有する局である。FIG. 3 shows an embodiment of the present invention intended for the FDMA mobile satellite communication system. In the mobile satellite communication system, the frequency assigned to communication between a base station and a satellite is different from the frequency assigned to communication between a mobile station and a satellite. Therefore, in the satellite repeater shown in FIG. 3, the receiver 27, 29, the transmitter 28,
In addition, a frequency converter 31 is required for communication between mobile stations. In the following, a case will be explained in which the gain fluctuation of a satellite repeater that connects mobile stations is corrected. The base station 21 in FIG. 3 transmits a signal wave fh toward the satellite. This signal wave fh passes through the satellite antenna, the transmitter/receiver splitter 5, the receiver 27, the transmitter 30, the transmitter/receiver splitter A, and the satellite antenna, and is then received by the pseudo mobile station as a signal wave f8'. Ru. Here, the pseudo mobile station is a station that is installed adjacent to a base station and has a mobile station antenna, a transmitter/receiver duplexer, and a transceiver.
擬似移動局ではこの受信されたｆＡ′の受信レベルを検
出し、この検出結果を信号線３４により基地局に伝達す
る。基地局２１はこの検出結果にもとづいてｆへの送信
レベルを変化し、ｆＡＩの衛星出力レベルを一定とする
゛。擬似移動局ｎは信号波ｆＡ／を受信Ｉるとともに、
送信出力レベル一定の信号波ｆＢを衛星に向けて送信す
る。この信号波ｆＢは第１図の冴、２６．２９．３１．
３２．３０．２６．２４を経由して信号波ｆＢ′となっ
て衛星より送信される。つぎに、衛星中継器の送信機３
０では信号波ｆｈおよびｆＢに対応した信号波ｆＡ′お
よびｆＢ′を分岐した信号を相対レベル差検出器３３に
供給する。ここで信号波ｆＡ／は常に一定レベルとなる
ようにレベル制御された信号であり、またもう１つの信
号波ｆＢ′は衛星中継器の２９．３１．３０の利得変動
に応じたレベル変化を有する信号である。このため、検
出器３３でｆＡ′とｆＢ′の相対レベル差の変動を検出
することにより、衛星中継器の２９、３１．３０の利得
変動に比例したレベル情報が得られる。この情報で可変
減衰器３２の減衰量を制御して利得変動の補正を行うこ
とができる。The pseudo mobile station detects the reception level of the received fA' and transmits the detection result to the base station via the signal line 34. The base station 21 changes the transmission level to f based on this detection result, and keeps the satellite output level of fAI constant. The pseudo mobile station n receives the signal wave fA/, and
A signal wave fB with a constant transmission output level is transmitted toward the satellite. This signal wave fB is shown in Fig. 1, 26.29.31.
32.30.26.24, and is transmitted from the satellite as a signal wave fB'. Next, transmitter 3 of the satellite repeater
0, a signal obtained by branching the signal waves fA' and fB' corresponding to the signal waves fh and fB is supplied to the relative level difference detector 33. Here, the signal wave fA/ is a signal whose level is controlled so that it is always at a constant level, and the other signal wave fB' has a level change according to the gain fluctuation of the satellite repeater. It's a signal. Therefore, by detecting fluctuations in the relative level difference between fA' and fB' with the detector 33, level information proportional to gain fluctuations of 29 and 31.30 of the satellite repeater can be obtained. Using this information, the amount of attenuation of the variable attenuator 32 can be controlled to correct gain fluctuations.
（発明の効果）
以上説明したように、本発明による方式は衛星送信出力
が一定レベルとなるように制御された信号波と衛星中継
器の利得変動によりレベルが変化する信号波の２つの信
号波の相対レベル差を衛星中継器上で検出して衛星中継
器の利得変動を補正している。このため、衛星中継器の
周囲温度変化によるレベル検出器の特性劣化が信号波の
絶対レベルを検出する検出器に比較して小さく、精度の
高い補正効果を得ることができる利点がある。(Effects of the Invention) As explained above, the method according to the present invention uses two signal waves, one controlled so that the satellite transmission output is at a constant level, and the other whose level changes due to gain fluctuations of the satellite repeater. The relative level difference between the two is detected on the satellite transponder and the gain fluctuation of the satellite transponder is corrected. Therefore, there is an advantage that the characteristic deterioration of the level detector due to changes in the ambient temperature of the satellite repeater is smaller than that of a detector that detects the absolute level of a signal wave, and a highly accurate correction effect can be obtained.
なお、本発明の説明で述べたある特定の信号波ＣｆＡ、
ｆＢ ）は衛星中継器利得変動補正用の信号波として
使用すると同時に、周波数変動補正用のパイロット信号
、あるいは制御回線の信号と併用して使用することもで
きる。Note that a certain signal wave CfA mentioned in the explanation of the present invention,
fB) can be used as a signal wave for correcting satellite repeater gain fluctuations, and can also be used in combination with a pilot signal for frequency fluctuation correction or a control line signal.
また、第１図において、地球局への送信レベル制御速度
が衛星中継器４の可変減衰器８０制御速度より十分速い
場合には、信号波ｆｉ／とｆＢ′を分離する分波器７、
合波器１０、固定減衰器９を省略し、受信機６のｆへ′
とｊＢ′の出力を可変減衰器８に供給しても本発明の動
作はそこなわれることはない。In addition, in FIG. 1, if the transmission level control speed to the earth station is sufficiently faster than the control speed of the variable attenuator 80 of the satellite repeater 4, a duplexer 7 that separates the signal waves fi/ and fB';
The multiplexer 10 and the fixed attenuator 9 are omitted, and the signal is sent to f of the receiver 6'
Even if the outputs of and jB' are supplied to the variable attenuator 8, the operation of the present invention will not be impaired.
第１図は本発明の一実施例を示す図、第２図は第１図の
地球局Ａの詳細図、第３図は本発明の別の実施例を示す
図である。
１・・・地球局（５）、２・・・地球局（Ｂｌ、３・・
・衛星アンテナ、４・・・衛星中継器、５・・・送受分
波器、６・・・受信機、７・・・分波器、８・・・可変
減衰器、９・・・固定減衰器、１０・・・合波器、１１
・・・送信機、１２・・・相対レベル差検出器、１３・
・・地球局アンテナ、１４・・・送受分波器、１５・・
・受信機、１６・・・受信レベル検出器、１７・・・送
信機、１８・・・可変減衰器、１９・・・信号波生成回
路、２１・・・基地局、２２・・・擬似移動局、乙・・
・衛星アンテナ（基地局用）、Ｕ・・・衛星アンテナ（
移動局用）、５．２６・・・送受分波器、２７・・・受
信機、２８・・・送信機、２９・・・受信機、３０・・
・送信機、３１・・・周波数変換器、３２・・・可変減
衰器、３３・・・相対レベル差検出器、３４・・・信号
線。
特許出願人
日本電信電話公社
特許出願代理人
弁理士 山本恵−
第１図
７，４
ｒ ”＠FIG. 1 is a diagram showing one embodiment of the present invention, FIG. 2 is a detailed view of earth station A in FIG. 1, and FIG. 3 is a diagram showing another embodiment of the present invention. 1... Earth station (5), 2... Earth station (Bl, 3...
・Satellite antenna, 4... Satellite repeater, 5... Transmission/reception duplexer, 6... Receiver, 7... Duplexer, 8... Variable attenuator, 9... Fixed attenuation Device, 10... Multiplexer, 11
...Transmitter, 12...Relative level difference detector, 13.
...Earth station antenna, 14...Transmission/reception duplexer, 15...
-Receiver, 16... Reception level detector, 17... Transmitter, 18... Variable attenuator, 19... Signal wave generation circuit, 21... Base station, 22... Pseudo movement Bureau, B...
・Satellite antenna (for base station), U...satellite antenna (
(for mobile station), 5.26...transmission/reception duplexer, 27...receiver, 28...transmitter, 29...receiver, 30...
- Transmitter, 31... Frequency converter, 32... Variable attenuator, 33... Relative level difference detector, 34... Signal line. Patent applicant Nippon Telegraph and Telephone Public Corporation Patent application agent Megumi Yamamoto - Figure 1 7, 4 r ”@
Claims (1)
において、衛星送信出方レベルが常に一定となるように
地球局の送信レベルが制御されたある特定の信号波と、
地球局の送信レベルか−、定のある特定の信号波の各々
の衛星送信出力レベルの相対レベル差を衛星上で検出し
、この検出結果にもとづいて衛星中継器の利得を一定と
するごとく制御することを特徴とする衛星中継器利得変
動補正方式。In a satellite communication system that uses multiple carrier waves to set up a satellite line, a certain signal wave whose transmission level from the earth station is controlled so that the satellite transmission output level is always constant,
The relative level difference between the earth station's transmission level and the satellite transmission output level of each specific signal wave is detected on the satellite, and based on this detection result, the gain of the satellite repeater is controlled to be constant. A satellite repeater gain fluctuation correction method characterized by:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11506783A JPS609231A (en) | 1983-06-28 | 1983-06-28 | Correcting system for gain variance of satellite repeater |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11506783A JPS609231A (en) | 1983-06-28 | 1983-06-28 | Correcting system for gain variance of satellite repeater |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS609231A true JPS609231A (en) | 1985-01-18 |
Family
ID=14653354
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP11506783A Pending JPS609231A (en) | 1983-06-28 | 1983-06-28 | Correcting system for gain variance of satellite repeater |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS609231A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05218920A (en) * | 1992-02-03 | 1993-08-27 | Nec Corp | Control system for satellite communication equipment transmission power |
| EP1645545A1 (en) | 2004-10-06 | 2006-04-12 | Schott AG | Process for making lenses and tool for pressing a glass blank |
-
1983
- 1983-06-28 JP JP11506783A patent/JPS609231A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05218920A (en) * | 1992-02-03 | 1993-08-27 | Nec Corp | Control system for satellite communication equipment transmission power |
| EP1645545A1 (en) | 2004-10-06 | 2006-04-12 | Schott AG | Process for making lenses and tool for pressing a glass blank |
| DE102004048500B4 (en) * | 2004-10-06 | 2009-11-05 | Schott Ag | Method for producing a projection headlight lens and a tool for molding |
| DE102004048500B9 (en) * | 2004-10-06 | 2010-03-25 | Schott Ag | Method for producing a projection headlight lens and a tool for molding |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5095528A (en) | Repeater with feedback oscillation control | |
| KR100341069B1 (en) | Dynamic control of transmitting power at a transmitter and attenuation at a receiver | |
| KR100353413B1 (en) | Booster, monitoring apparatus, booster system, control method and monitoring method | |
| USRE37870E1 (en) | CDMA/TDD radio communication system | |
| US3315164A (en) | Control of ground station transmitter power to supply suitable signal level to satellite repeater | |
| JPH04267612A (en) | Parallel amplifier and signal amplification method | |
| US4313220A (en) | Circuit and method for reducing polarization crosstalk caused by rainfall | |
| EP1219037B1 (en) | Method of measuring receiver sensitivity, and transceiver | |
| JPH04372234A (en) | Transmission power control system | |
| JPS609231A (en) | Correcting system for gain variance of satellite repeater | |
| JPS583613B2 (en) | Satellite communication method | |
| JP2965821B2 (en) | Wireless relay device | |
| JP2679445B2 (en) | Transmission power control method | |
| JP2504214B2 (en) | Automatic Level Control Method for Micro Satellite Communication Equipment | |
| JPS61195028A (en) | Repeater for communication satellite | |
| JP2842596B2 (en) | Earth station transmission power control method | |
| JP2795055B2 (en) | Transmission power control method | |
| US3440539A (en) | Remote controlled system for reducing distortion | |
| CN100512265C (en) | Gain measurement device for on-line calibration and method thereof | |
| JP2699725B2 (en) | Transmission power control method for multiple transponders | |
| JPS5884547A (en) | Transmission power control system of earth station for satellite communication | |
| JPH01181238A (en) | Transmission power control system | |
| JPH0376437A (en) | Automatic level control system for subminiature satellite communication equipment | |
| JPH02104131A (en) | Transmitter | |
| JPH0425222A (en) | Automatically level controlled system |