JPS59103433A - Compensating device of interference wave - Google Patents
Compensating device of interference waveInfo
- Publication number
- JPS59103433A JPS59103433A JP21269082A JP21269082A JPS59103433A JP S59103433 A JPS59103433 A JP S59103433A JP 21269082 A JP21269082 A JP 21269082A JP 21269082 A JP21269082 A JP 21269082A JP S59103433 A JPS59103433 A JP S59103433A
- Authority
- JP
- Japan
- Prior art keywords
- signal
- interference
- receiving antenna
- pilot
- antenna
- 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.)
- Granted
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/14—Relay systems
- H04B7/15—Active relay systems
- H04B7/155—Ground-based stations
- H04B7/15564—Relay station antennae loop interference reduction
- H04B7/15585—Relay station antennae loop interference reduction by interference cancellation
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】
本発明は送信アンテナから空間を介して受信アンテナへ
廻り込む干渉電波を軽減する装置に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for reducing interference radio waves that go around from a transmitting antenna to a receiving antenna through space.
無線信号を受信アンテナで受信し、これを増幅後送信ア
ンテナより同一周波数にて再送信する無線中継方式にお
いては、送信アンテナから発射された信号の一部が空間
を介した廻り込み電波として受信アンテナに於いて再受
信される場合がある。In the wireless relay method, in which a radio signal is received by a receiving antenna, and then retransmitted at the same frequency from a transmitting antenna after being amplified, a part of the signal emitted from the transmitting antenna is transmitted to the receiving antenna as a wraparound radio wave through space. It may be re-received at some point.
このような場合に、受信アンテナに於いては、正規の到
来電波による信号と廻り込み電波による干渉信号とが相
加される為、中継装置の機能を阻害する要因となり得る
。従来この干渉信号を補償する方法としては、第１図に
示すように振幅・位相を調整できる帰還回路を中継装置
の送信端から受信端の間に設け、その帰還信号を干渉信
号と逆相等振幅にすることＫより干渉信号を相殺する構
成がある。図中、工は受信アンテナ、２は送信アンテナ
、３は中継増幅器、５は半固定移相器、６は半固定減衰
器、４は干渉補償のための帰還ループである。帰還ルー
プ４からの帰還信号が干渉信号を相殺する条件である逆
相・等振幅の条件の設定は、半固定移相器５と半固定減
衰器６の調整により行われろ。通常この調整は、測定器
を用いて手動で行われるため、極めて不便である。また
、一度調整が良好になされても、増幅器特性や送受アン
テナ間伝搬路特性の変動により干渉信号と帰還信号との
相殺状態が劣化するため、定常的に補償特性が得られな
い欠点があった。In such a case, at the receiving antenna, the signal due to the regular incoming radio wave and the interference signal due to the detouring radio wave are added, which may become a factor that inhibits the function of the relay device. Conventionally, as a method of compensating for this interference signal, as shown in Figure 1, a feedback circuit that can adjust the amplitude and phase is installed between the transmitting end and the receiving end of the repeater, and the feedback signal is sent to the interfering signal with the opposite phase and equal amplitude. There is a configuration that cancels out the interference signal. In the figure, numeral 1 is a receiving antenna, 2 is a transmitting antenna, 3 is a relay amplifier, 5 is a semi-fixed phase shifter, 6 is a semi-fixed attenuator, and 4 is a feedback loop for interference compensation. The conditions of opposite phase and equal amplitude under which the feedback signal from the feedback loop 4 cancels out the interference signal are set by adjusting the semi-fixed phase shifter 5 and the semi-fixed attenuator 6. This adjustment is usually done manually using a measuring instrument, which is very inconvenient. In addition, even if the adjustment is made well, the cancellation state between the interference signal and the feedback signal deteriorates due to variations in the amplifier characteristics and the propagation path characteristics between the transmitting and receiving antennas, so there is a drawback that compensation characteristics cannot be consistently obtained. .
本発明は、これらの欠点を解決するため、受信アンテナ
からパイロット信号を送出し、そのパイロット信号につ
いて帰還ループ信号と干渉信号との相殺残留成分を検出
することにより、帰還ループ信号の振幅と位相を制御し
自動的に最適補償条件を実現し、かつ受信アンテナより
パイロット信号を送出することによりパイロ、ト信号が
送信信号に与える影響を低減するようにした干渉波補償
装置を提供するものである。In order to solve these drawbacks, the present invention transmits a pilot signal from a receiving antenna, and detects the residual component of the pilot signal that cancels out the feedback loop signal and the interference signal, thereby determining the amplitude and phase of the feedback loop signal. The present invention provides an interference wave compensator that automatically realizes optimal compensation conditions through control and transmits a pilot signal from a receiving antenna to reduce the influence of pilot signals on transmitted signals.
以下図面により本発明の詳細な説明する。The present invention will be explained in detail below with reference to the drawings.
第２図は本発明の実施例であって、１は受信アンテナ、
２は送信アンテナ、３は中継増幅器、４は帰還ループ、
７は等振幅２相（０°、９０°）分配器、８は等振幅４
相（０°、９０°、１８０°、２７０°）分配器、９は
パイロット信号発生器、１０はパイロット信号除去沖波
器、ｌｌａとｌｌｂはパイロット信号検出Ｆ波器、１２
と１３は信号帯域通過Ｆ波器、１４はレベル調整のだめ
の増幅器、１５ａと１５ｂは同期検波器、１６ａと１６
ｂは電圧加算器、１７は整流器、１８は電気的可変減衰
器、１９ａ 、 １９ｂは可変遅延線路である。FIG. 2 shows an embodiment of the present invention, in which 1 is a receiving antenna;
2 is a transmitting antenna, 3 is a relay amplifier, 4 is a feedback loop,
7 is equal amplitude 2-phase (0°, 90°) distributor, 8 is equal amplitude 4
Phase (0°, 90°, 180°, 270°) distributor, 9 is a pilot signal generator, 10 is a pilot signal removal wave generator, lla and llb are pilot signal detection F wave generators, 12
and 13 are signal band-pass F wave filters, 14 is an amplifier for level adjustment, 15a and 15b are synchronous detectors, and 16a and 16
b is a voltage adder, 17 is a rectifier, 18 is an electrical variable attenuator, and 19a and 19b are variable delay lines.
受信アンテナ１で受信される信号は正規の到来電波によ
る信号（以下正規信号という）と、送信アンテナ２から
発射後空間を介して廻り込む干渉信号の合成されたもの
である。中継増幅器３０入力信号はこれからさらに帰還
ループ４を経由した帰還信号が相加されている。さて本
発明は干渉信号と帰還信号の相殺条件を自動的に実現す
るもので、その動作は次のとおりである。いま、受信ア
ンテナ１から単一周波数のノ（イロ、）信号が送出され
ている状態を考える。このときノくイロット信号検出ｐ
波器１１ａの出力信号は干渉信号伝搬路を伝搬した干渉
波路信号と帰還信号との合成信号であって、これを第３
図のベクトル図−で示す。ここで、同図中ｅ 、＋ ｅ
ｃはそれぞれ干渉波路信号および帰還信号を表わす。こ
の抽出されたノζイロット信号５ｓをパイロット信号発
生器９から分岐した信号の同相および直交成分を基準と
して同期検波器１５ａおよび１５ｂで同期検波すればベ
クトル６、の同相および直交成分ｅｘ＋ ｅｙが直流電
圧として検出できる。そこで、このｅｚ ｒ ｅｙの符
号を反転したベクトル−み。をさらにｅＢＫ相加すれば
・ζイロット検出Ｆ波器１１ｂの出力は消失し、干渉信
号と帰還信号の相殺条件が実現できる。これは具体的に
次のようにして実現される。１ず、同期検波器１５ａ、
１５ｂ ５−
で検出された同相成分ｅＸと直交成分ｅｙはそれぞれ電
圧加算器１６ａおよび１６ｂに入力され、その出力で等
振幅４相分配器８と電気的可変減衰器１８で構゛ 成さ
れるベクトル変調器を駆動する。ここで、ダイオード１
７は電圧加算器１６ａ 、 １６ｂの出力電圧の極性に
応じてベクトル変調器のＸ軸、Ｙ軸の極性を選択するも
ので、例えば敗が正ならばπ相の信号経路が導通となり
、その導通信号のレベルは検出電圧の大きさ例えば１ｅ
Ｘ１になるように電気的可変減衰器１８により設定され
る。このようＫして同期検波器１５ａ 、 １５ｂで検
出された電圧に対して、ベクトル変調器での制御を負帰
還状態にすることが可能である。例えば、第３図のベク
トル図に示すように送信アンテナより抽出したノぐイロ
ット信号成分の同相成分としてｅＸ、直交成分としてｅ
ｙが検出された場合、ベクトル変調器は帰還ル−プの出
力信号がそれ１での出力信号ｅｃにさらに−ｅｘｉ−ｅ
ｙｊ（但し１＋ｊはそれぞれ第３図Ｘ軸、Ｙ軸の単位ベ
クトル）すなわち−一の相加された信号となる。従って
、この制御により送信アンテナ２に−も−
より受信された信月中のパイロット信号の抑圧が実現さ
れる。The signal received by the receiving antenna 1 is a combination of a signal due to a regular arriving radio wave (hereinafter referred to as a regular signal) and an interference signal that is emitted from the transmitting antenna 2 and then circulates through space. A feedback signal via a feedback loop 4 is further added to the input signal of the relay amplifier 30. Now, the present invention automatically realizes the conditions for canceling the interference signal and the feedback signal, and its operation is as follows. Now, consider a situation where a single frequency signal is being transmitted from the receiving antenna 1. At this time, the signal detection p
The output signal of the wave transmitter 11a is a composite signal of the interference wave path signal propagated through the interference signal propagation path and the feedback signal, which is
It is shown in the vector diagram - in the figure. Here, e, + e in the same figure
c represent the interference wavepath signal and the feedback signal, respectively. If this extracted pilot signal 5s is synchronously detected by the synchronous detectors 15a and 15b using the in-phase and quadrature components of the signal branched from the pilot signal generator 9 as a reference, the in-phase and quadrature components ex+ ey of the vector 6 become DC. Can be detected as voltage. Therefore, the vector obtained by inverting the sign of this ez rey. If eBK is further added to .zeta., the output of the F wave detector 11b disappears, and the condition for canceling the interference signal and the feedback signal can be realized. Specifically, this is achieved as follows. 1. Synchronous detector 15a,
The in-phase component e Drive the modulator. Here, diode 1
7 selects the polarity of the X-axis and Y-axis of the vector modulator according to the polarity of the output voltage of the voltage adders 16a and 16b; for example, if the loss is positive, the π-phase signal path becomes conductive; The signal level is determined by the magnitude of the detection voltage, for example 1e.
It is set by the electrical variable attenuator 18 so that it becomes X1. In this way, it is possible to put the vector modulator in a negative feedback state for the voltages detected by the synchronous detectors 15a and 15b. For example, as shown in the vector diagram in Figure 3, e
If y is detected, the vector modulator changes the output signal of the feedback loop to the output signal ec at 1 in addition to -exi-e
yj (where 1+j are the unit vectors of the X-axis and Y-axis, respectively, in FIG. 3), that is, the signal is an added signal of -1. Therefore, by this control, suppression of the pilot signal during the signal period received by the transmitting antenna 2 is realized.
さて、送信アンテナ２より送出され、受信アンテナ１で
受信されろ干渉信号の伝搬経路と帰還ループはともに可
逆性があり、前記のパイロット信号の抑圧条件は送信ア
ンテナ２より送出される実際の信号による干渉信号が帰
還信号により相殺されろ条件に一致するので、本発明を
アンテナ間干渉の自動補償装置に応用できる。この際パ
イロット信号除去沖波器１０は主信号経路のパイロット
信号成分を除去するもので、これにより残留パイロット
成分が出力側に現われることにより空間を介して送信ア
ンテナ２より受信されるパイロット信号と干渉すること
を防止する。なお、加算される制御布、圧の−６８に対
する近似性はより良い方が収束を早めるので望ましいが
、近似性が良好でなくとも制御は負帰還となっているの
で収束し、干渉信号の抑圧は可能である。また、同期検
波器１５ａ。Now, both the propagation path and the feedback loop of the interference signal transmitted from the transmitting antenna 2 and received by the receiving antenna 1 are reversible, and the conditions for suppressing the pilot signal described above depend on the actual signal transmitted from the transmitting antenna 2. Since the interference signal satisfies the condition that it is canceled by the feedback signal, the present invention can be applied to an automatic compensation device for inter-antenna interference. At this time, the pilot signal removal transducer 10 removes the pilot signal component in the main signal path, and as a result, residual pilot components appear on the output side and interfere with the pilot signal received from the transmitting antenna 2 through space. prevent this from happening. It should be noted that it is desirable that the approximation of the added control cloth to -68 of the pressure be better because convergence will be faster, but even if the approximation is not good, the control will converge due to negative feedback, and the interference signal will be suppressed. is possible. Also, a synchronous detector 15a.
１５ｂの基準信号ならびに入力信号とベクトル変調器の
出力信号との位相同期はそれぞれ可変遅延線路１９ａ
、 １９ｂの調整により行ない、捷だ、パイロット除去
Ｆ波器１０はパイロット信号が信号帯域通過Ｆ波器】２
で十分に除去可能なときは不要である。The phase synchronization between the reference signal 15b and the input signal and the output signal of the vector modulator is achieved through variable delay lines 19a, respectively.
, 19b is adjusted, and the pilot removal F-wave converter 10 is a pilot signal bandpass F-wave converter]2
It is not necessary if it can be sufficiently removed by
以上説明したように、本発明を用いることにより、アン
テナ受信信号において干渉波信号をアンテナ送受聞伝搬
路および中継増幅器の特性変動と無関係に自動的に低減
することが可能となるから、送受信号周波数が同一であ
る無線中継方式において送受アンテナ間の干渉信号を補
償することができ、中継装置の増幅利得として送受アン
テナ間結合減衰量（干渉補償を用いない場合の値）以上
のものを配分できる。また、受信アンテナよりパイロッ
ト信号を送出することから、送信信号に混入するパイロ
ット信号のレベルは極めて低（なるため、パイロット信
号を挿入したことにより中継増幅する信号にパイロット
信号による干渉歪が発生するといった悪影響が生ずるこ
とを防止できる利点がある。As explained above, by using the present invention, it is possible to automatically reduce the interference wave signal in the antenna reception signal regardless of the characteristic fluctuations of the antenna transmission/reception propagation path and the relay amplifier. It is possible to compensate for interference signals between the transmitting and receiving antennas in a radio relay system in which the transmitting and receiving antennas are the same, and it is possible to allocate more than the coupling attenuation between the transmitting and receiving antennas (the value when no interference compensation is used) as the amplification gain of the relay device. In addition, since the pilot signal is sent out from the receiving antenna, the level of the pilot signal mixed into the transmitted signal is extremely low. This has the advantage of preventing adverse effects from occurring.
第１図は従来の干渉補償装置の−例を示すブロック図、
第２図は本発明の一実施例を示すブロック図、第３図は
受信パイロット信号のベクトル図である。
１・・・受信アンテナ、２・・・送信アンテナ、３・・
・中継増幅器、４・・・帰還ループ、５・・・半固定移
相器、６・・・半固定減衰器、７・・・等振幅２相分配
器、８・・・等振幅４相分配器、９・・・パイロット信
号発生器、 １０・・・パイロット信号除去Ｆ波器、］
１・・・パイロット信号検出Ｐ波器、１２ 、１３・・
・信号帯域通過沖波器、 １４・・・増幅器、１５ａ
、 １５ｂ・・・同期検波器、１６ａ 、 １６ｂ・・
・電圧加算器、 １７・・・ダイオード、 １８・・・
電気的可変減衰器、１９ａ 、 １９ｂ・・・可変遅延
線路、 ２０・・・抽出されたパイロット信号ベクトル
、 ２１・・・干渉信号ベクトル、 ２２・・・帰還信
号ベクトル、 ２３・・・パイロット信号の逆ベクトル
、 ２４・・・パイロット信号ベクトルのＸ成分（同相
成分）、 ２５・・・・５イヮ、ッ・ト信号ベクトルの
Ｙ成分（直交成分）、２６ａ、２６ｂ・・・サーキュレ
ータ。
９−
第 １ 図FIG. 1 is a block diagram showing an example of a conventional interference compensation device,
FIG. 2 is a block diagram showing an embodiment of the present invention, and FIG. 3 is a vector diagram of received pilot signals. 1...Receiving antenna, 2...Transmitting antenna, 3...
・Relay amplifier, 4... Feedback loop, 5... Semi-fixed phase shifter, 6... Semi-fixed attenuator, 7... Equal amplitude 2-phase divider, 8... Equal amplitude 4-phase distribution 9...Pilot signal generator, 10...Pilot signal removal F-wave device,]
1... Pilot signal detection P wave device, 12, 13...
・Signal bandpass transducer, 14...Amplifier, 15a
, 15b...Synchronous detector, 16a, 16b...
・Voltage adder, 17...diode, 18...
Electrical variable attenuator, 19a, 19b... Variable delay line, 20... Extracted pilot signal vector, 21... Interference signal vector, 22... Feedback signal vector, 23... Pilot signal vector. Inverse vector, 24...X component (in-phase component) of the pilot signal vector, 25...5 Y component (orthogonal component) of the t signal vector, 26a, 26b... circulator. 9- Figure 1
Claims (1)
増幅し該受信信号と同一周波数で送信アンテナから送信
信号として再送信する無線中継装置において、前記受信
アンテナより特定周波数のパイロット信号を送出する手
段と、前記送信アンテナより該パイロット信号を抽出す
る手段と、前記受信信号へ廻り込む前記パイロ、ト信号
を除去して前記受信信号を前記増幅器に印加する手段と
。 前記パイロット信号及び前記送信信号の一部を分岐して
振幅・位相を調整するためのベクトル変調器に印加する
手段と、該ベクトル変調器の送信信号出力とパイロ、ト
信号出力とを前記受信信号の経路及び前記送信信号の経
路にそれぞれ帰還する手段と、前記送信アンテナから抽
出したパイロン１− ト信号の同相成分および直交成分を検出する手段と、検
出された同相成分および直交成分の情報により前記ベク
トル変調器を制御する手段とを有し、前記送信アンテナ
より空間を介して前記受信アンテナに帰還する干渉信号
を低減させるように構成されたことを特徴とする干渉波
補償装置。[Claims] In a radio relay device that receives a radio signal with a receiving antenna, amplifies the received signal with an amplifier, and retransmits it as a transmitting signal from a transmitting antenna at the same frequency as the received signal, wherein a pilot signal of a specific frequency is transmitted from the receiving antenna. means for transmitting a signal; means for extracting the pilot signal from the transmitting antenna; and means for removing the pilot signal from the received signal and applying the received signal to the amplifier. means for branching the pilot signal and a part of the transmission signal and applying it to a vector modulator for adjusting the amplitude and phase; means for returning to the path of the pylon and the transmission signal, means for detecting an in-phase component and a quadrature component of the pylon-to-signal extracted from the transmitting antenna, An interference wave compensating device comprising: means for controlling a vector modulator, and configured to reduce interference signals that return from the transmitting antenna to the receiving antenna via space.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21269082A JPS59103433A (en) | 1982-12-06 | 1982-12-06 | Compensating device of interference wave |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21269082A JPS59103433A (en) | 1982-12-06 | 1982-12-06 | Compensating device of interference wave |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS59103433A true JPS59103433A (en) | 1984-06-14 |
| JPS643099B2 JPS643099B2 (en) | 1989-01-19 |
Family
ID=16626807
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP21269082A Granted JPS59103433A (en) | 1982-12-06 | 1982-12-06 | Compensating device of interference wave |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59103433A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5860057A (en) * | 1995-03-15 | 1999-01-12 | Hitachi, Ltd. | Satellite communications system and method |
| JP2001077739A (en) * | 1999-07-20 | 2001-03-23 | Andrew Corp | Flank-to-flank repeater and its operating method |
| KR100350968B1 (en) * | 2000-04-20 | 2002-08-28 | 이종삼 | Coupled interference cancellation system for wideband repeaters in a cellular system |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS55133148A (en) * | 1979-04-04 | 1980-10-16 | Nippon Telegr & Teleph Corp <Ntt> | Interference wave removal system |
| JPS5619239A (en) * | 1979-06-08 | 1981-02-23 | Plessey Handel Investment Ag | Am double communication transceiver |
-
1982
- 1982-12-06 JP JP21269082A patent/JPS59103433A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS55133148A (en) * | 1979-04-04 | 1980-10-16 | Nippon Telegr & Teleph Corp <Ntt> | Interference wave removal system |
| JPS5619239A (en) * | 1979-06-08 | 1981-02-23 | Plessey Handel Investment Ag | Am double communication transceiver |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5860057A (en) * | 1995-03-15 | 1999-01-12 | Hitachi, Ltd. | Satellite communications system and method |
| JP2001077739A (en) * | 1999-07-20 | 2001-03-23 | Andrew Corp | Flank-to-flank repeater and its operating method |
| KR100350968B1 (en) * | 2000-04-20 | 2002-08-28 | 이종삼 | Coupled interference cancellation system for wideband repeaters in a cellular system |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS643099B2 (en) | 1989-01-19 |
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