JPH055764A - Measuring method of gain of antenna - Google Patents

Measuring method of gain of antenna

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Publication number
JPH055764A
JPH055764A JP31695891A JP31695891A JPH055764A JP H055764 A JPH055764 A JP H055764A JP 31695891 A JP31695891 A JP 31695891A JP 31695891 A JP31695891 A JP 31695891A JP H055764 A JPH055764 A JP H055764A
Authority
JP
Japan
Prior art keywords
antenna
frequency
gain
signal
wave
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
Application number
JP31695891A
Other languages
Japanese (ja)
Other versions
JPH0577988B2 (en
Inventor
Kenji Oumaru
謙治 王丸
Hiroo Isono
宏夫 礒野
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Japan Broadcasting Corp
Original Assignee
Nippon Hoso Kyokai NHK
Japan Broadcasting Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Nippon Hoso Kyokai NHK, Japan Broadcasting Corp filed Critical Nippon Hoso Kyokai NHK
Priority to JP31695891A priority Critical patent/JPH055764A/en
Publication of JPH055764A publication Critical patent/JPH055764A/en
Publication of JPH0577988B2 publication Critical patent/JPH0577988B2/ja
Granted legal-status Critical Current

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Abstract

PURPOSE:To correctly measure the gain of a sample antenna by measuring the detecting level of a modulated wave of a receiving frequency by a first antenna, replacing the first antenna with the sample antenna whose gain is unknown and measuring the detecting level. CONSTITUTION:A frequency converter 2 converts the receiving wave of ft1 frequency to a signal of fL-fL1 frequency. The fL1 is the oscillating frequency of a local oscillator of the converter 2. The receiving wave of ft frequency is converted to a signal of ft-fL3 frequency by a frequency converter 8. The fL3 is the oscillating frequency of a local oscillator of the converter 8. The frequency component which is turned not to modulate is passed through a narrow band pass filter 11, and accordingly the noise component is removed and only the signal component is obtained. The level is measured by a level measuring device 12. A gain reference antenna 7 is replaced with a sample antenna 13 the gain of which is not known. The increasing amount L of the attenuation is measured. The gain G of the antenna 13 is obtained by an equation G=Gs+L wherein Gs is the gain of the antenna 7.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】この発明は衛星放送波などの周波
数変調された微弱電波を用いてアンテナ利得を正確に測
定する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 method for accurately measuring an antenna gain by using frequency-modulated weak radio waves such as satellite broadcast waves.

【0002】[0002]

【従来の技術】前述の方法を達成するには、利得既知の
利得基準アンテナおよび利得未知の供試アンテナを用い
て周波数変調された電波を受信し、両者の受信レベルを
正確に測定し比較する必要がある。
2. Description of the Related Art In order to achieve the above method, a frequency-modulated radio wave is received using a gain reference antenna with a known gain and a test antenna with a unknown gain, and the reception levels of both are accurately measured and compared. There is a need.

【0003】従来、この方法によりアンテナ利得を測定
するには、まず利得が既知の利得基準アンテナで周波数
変調波を受信し、その出力を較正された受信機あるいは
電力計で測定するなどの手段を講じていたが、利得基準
アンテナの利得は概して小さいので、周波数変調された
微弱電波の場合には、受信電波の信号対雑音比C/Nが
小さく、受信機や電力計では正確に測定できない欠点が
あった。又スペクトラムアナライザーによる狭帯域受信
で雑音レベルを下げることが考えられるが、その場合で
も周波数変調されていること、および衛星放送波の場合
には変調信号にエネルギー拡散信号が重畳されているこ
となどによって、受信電波のエネルギーが周波数的に分
散され、しかも分散の仕方が時間的に変動するのでスペ
クトラムアナライザーによっては正確に測定できなかっ
た。従って利得未知のアンテナ利得を正確に測定するこ
ともできない欠点があった。
Conventionally, in order to measure the antenna gain by this method, first, a frequency reference wave is received by a gain reference antenna whose gain is known, and its output is measured by a calibrated receiver or a power meter. However, the gain of the gain reference antenna is generally small, so in the case of weak frequency-modulated radio waves, the signal-to-noise ratio C / N of the received radio waves is small and cannot be accurately measured by a receiver or a power meter. was there. It is also possible to lower the noise level by narrow band reception with a spectrum analyzer, but even in that case, due to frequency modulation and in the case of satellite broadcast waves, the energy spread signal is superimposed on the modulation signal. However, the energy of the received radio wave is dispersed in frequency, and the way of dispersion varies with time, so it could not be measured accurately by a spectrum analyzer. Therefore, there is a drawback that the antenna gain of unknown gain cannot be accurately measured.

【0004】[0004]

【発明が解決しようとする課題】前述の(従来の技術)
の項でも述べたように、周波数変調された微弱電波の場
合には、受信電波の信号対雑音比が小さく、従来の方法
ではその受信信号レベルを正確に測定できない、従って
利得未知のアンテナ利得を正確に測定することもできな
い欠点があった。
DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention (Prior Art)
As described in the section above, in the case of frequency-modulated weak radio waves, the signal-to-noise ratio of the received radio waves is small, and the received signal level cannot be accurately measured by the conventional method. There was a drawback that it could not be measured accurately.

【0005】そこで本発明の目的は上記従来の欠点を除
去し、比較的簡便な方法で、信号対雑音比が小さく、微
弱な周波数変調波の受信信号レベルを精度よく測定で
き、従って利得未知のアンテナ利得を正確に測定できる
アンテナ利得の測定方法を提供せんとするものである。
Therefore, an object of the present invention is to eliminate the above-mentioned conventional drawbacks and to measure the received signal level of a weak frequency-modulated wave with a small signal-to-noise ratio with a relatively simple method with high accuracy. An object of the present invention is to provide an antenna gain measuring method capable of accurately measuring the antenna gain.

【0006】[0006]

【課題を解決するための手段】その目的を達成するため
本発明アンテナ利得の測定方法は、あらかじめ利得の判
明している周波数変調波を受信する第1のアンテナと、
当該第1のアンテナより高利得でそれと同じ周波数変調
波を受信する第2のアンテナと、前記第1のアンテナの
第1の受信出力および前記第2のアンテナの第2の受信
出力から周波数変調成分の除去された無変調波成分を抽
出するため、前記第1の受信出力および前記第2の受信
出力の少なくとも一方に設けられた少なくとも1つの中
間周波数変換手段と、前記無変調波成分を抽出する手段
と、当該抽出された無変調波成分から前記周波数変調波
の受信レベルを求める手段とを備えた周波数変調波の受
信レベル測定装置を用意し、はじめに前記第1のアンテ
ナにより受信周波数変調波の受信レベルを測定し、次に
前記第1のアンテナを利得未知の供試アンテナに置換し
てその受信レベルを測定し、これによって前記利得未知
の供試アンテナの利得を測定するようにしたことを特徴
とするものである。
In order to achieve the object, an antenna gain measuring method according to the present invention comprises: a first antenna for receiving a frequency-modulated wave whose gain is known in advance;
A second antenna that has a higher gain than the first antenna and receives the same frequency-modulated wave, and a frequency-modulated component from the first received output of the first antenna and the second received output of the second antenna. In order to extract the removed non-modulation wave component, at least one intermediate frequency conversion means provided in at least one of the first reception output and the second reception output, and the non-modulation wave component are extracted. A reception level measuring device for a frequency modulation wave is provided, which comprises a means and a means for obtaining a reception level of the frequency modulation wave from the extracted non-modulation wave component, and first, the reception frequency modulation wave of the reception frequency modulation wave is received by the first antenna. The reception level is measured, and then the first antenna is replaced with a test antenna of unknown gain, and the reception level is measured. It is characterized in that the resulting was to measure.

【0007】[0007]

【実施例】以下添付図面を参照し実施例により本発明を
詳細に説明する。図1に本発明方法を達成するための第
1の実施例構成ブロック線図を示す。
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 shows a block diagram of the configuration of a first embodiment for achieving the method of the present invention.

【0008】図1において1は高利得アンテナであり、
微弱電波の場合でもC/Nが大きい信号を受信する。2
は周波数コンバーターであり、周波数がf(t) の受信波
を周波数がf(t) −fL1の信号に変換する。ただしfL1
は周波数コンバーター2の局部発振器の発振周波数であ
る。さらにミキサー3によって周波数がfL2の局部発振
器(LOSC)4の信号と混合し、周波数がf(t) −fL1−f
L2の周波数成分をバンドパスフィルター(BPF) 5によっ
て取り出し、振幅制限器6によって振幅を一定にする。
7は利得が既知の利得基準アンテナであり、周波数がf
(t) の受信波を周波数コンバーター8によって周波数が
(t) −fL3の信号に変換する。ただしfL3は周波数コ
ンバーター8の局部発振器の発振周波数である。可変遅
延時間器9によって遅延時間を調整して、可変遅延時間
器9および振幅制限器6の出力での信号の遅延時間を同
一にする。可変遅延時間器9の出力信号と振幅制限器6
の出力信号とをミキサー10によって混合し、周波数f
(t) −fL3−{f(t) −fL1−fL2}=fL1+fL2−f
L3の無変調化された周波数成分を狭帯域バンドパスフィ
ルター(BPF)11 によって雑音成分を除去し、信号成分だ
けを取り出し、レベル測定器12によってレベルを測定す
る。
In FIG. 1, 1 is a high gain antenna,
A signal with a large C / N is received even in the case of weak radio waves. Two
Is the frequency converter, the frequency is the frequency of the received wave f (t) is converted into a signal f (t) -f L1. However, f L1
Is the oscillation frequency of the local oscillator of the frequency converter 2. Further, the signal is mixed with the signal of the local oscillator (LOSC) 4 having the frequency f L2 by the mixer 3, and the frequency f (t) −f L1 −f
The frequency component of L2 is taken out by the bandpass filter (BPF) 5 and the amplitude is made constant by the amplitude limiter 6.
7 is a gain reference antenna whose gain is known, and whose frequency is f
Frequency by a frequency converter 8 received wave (t) is converted into a signal f (t) -f L3. However, f L3 is the oscillation frequency of the local oscillator of the frequency converter 8. The delay time is adjusted by the variable delay time device 9 so that the signal delay time at the output of the variable delay time device 9 and the delay time of the signal at the output of the amplitude limiter 6 become the same. Output signal of variable delay time device 9 and amplitude limiter 6
The output signal of is mixed by the mixer 10 and the frequency f
(t) −f L3 − {f (t) −f L1 −f L2 } = f L1 + f L2 −f
A narrowband bandpass filter (BPF) 11 removes a noise component from the non-modulated frequency component of L3 , extracts only a signal component, and measures the level with a level measuring device 12.

【0009】次に上述の基本構成の測定装置を用いて利
得未知のアンテナの利得を測定する。図1において利得
基準アンテナ7を、利得未知の供試アンテナ13に置換し
て、レベル測定器12の指示値が利得基準アンテナ7の場
合と同一になるように、可変抵抗減衰器14を調整し、そ
の時の減衰量の増加量L(dB)を測定する。供試アンテナ
13の利得G(dB)は利得基準アンテナ7の利得をGs (dB)
とすると次式で与えられる。
Next, the gain of the antenna of unknown gain is measured by using the measuring device having the above-mentioned basic structure. In FIG. 1, the gain reference antenna 7 is replaced with a test antenna 13 of unknown gain, and the variable resistance attenuator 14 is adjusted so that the level measurement device 12 has the same value as the gain reference antenna 7. Then, measure the increase amount L (dB) of the attenuation amount at that time. Test antenna
The gain G (dB) of 13 is the gain of the gain reference antenna 7 by G s (dB)
Then, it is given by the following equation.

【数1】G=Gs +L(dB) (1)[Equation 1] G = G s + L (dB) (1)

【0010】図2に示す本発明方法を達成するための第
2の実施例構成ブロック線図は図1に示した構成と基本
的には同じであるが、電界強度に時間変動があってもア
ンテナ利得の測定を可能にするため以下に述べる点が異
なっている。図2における周波数コンバーター2の出力
(f(t) −fL1)を分配器15によって分配し、一方の出
力を可変抵抗減衰器16によってレベルを調整した後、周
波数コンバーター8の出力(f(t) −fL3)と合成器17
によって合成する。その場合BPF 11の出力をスペクトラ
ムアナライザー18によって測定すると、利得基準アンテ
ナ7による受信信号と高利得アンテナ1による受信信号
を、周波数コンバーター2(fL1)および8(fL3)の
局部発振周波数の差(fL1−fL3)だけずれた位置に同
時に表示することができる。スペクトラムアナライザー
18上の二つの信号レベルが同一になるように可変抵抗減
衰器16を調整した後、利得基準アンテナ7を供試アン
テナ13に置換し、再びスペクトラムアナライザー上の二
つの信号のレベルが同一になるように可変抵抗減衰器14
を調整して、その減衰量の増加量L(dB)を測定すると、
供試アンテナ13の利得G(dB)は、利得基準アンテナ7の
利得をGs (dB)とすると再び式(1) で与えられる(G=
s +L)。
The block diagram of the second embodiment for achieving the method of the present invention shown in FIG. 2 is basically the same as the structure shown in FIG. 1, but even if the electric field strength varies with time. The following points are different so that the antenna gain can be measured. The output (f (t) -f L1 ) of the frequency converter 2 in FIG. 2 is distributed by the distributor 15, and one output is adjusted in level by the variable resistance attenuator 16, and then the output of the frequency converter 8 (f (t ) -F L3 ) and combiner 17
Synthesize by. In that case, when the output of the BPF 11 is measured by the spectrum analyzer 18, the signal received by the gain reference antenna 7 and the signal received by the high gain antenna 1 are compared with each other by the difference between the local oscillation frequencies of the frequency converters 2 (f L1 ) and 8 (f L3 ). It is possible to display simultaneously at positions shifted by (f L1 −f L3 ). Spectrum analyzer
After adjusting the variable resistance attenuator 16 so that the two signal levels on 18 are the same, the gain reference antenna 7 is replaced with the test antenna 13, and the two signal levels on the spectrum analyzer are again the same. Variable resistance attenuator 14
Is adjusted and the increase L (dB) of the attenuation is measured,
The gain G (dB) of the sample antenna 13 is again given by the equation (1) when the gain of the gain reference antenna 7 is G s (dB) (G =
G s + L).

【0011】図3に受信電界変動時に供試アンテナの利
得を測定する本発明方法を達成するための第3の実施例
構成ブロック線図を示す。
FIG. 3 shows a block diagram of the configuration of a third embodiment for achieving the method of the present invention for measuring the gain of the antenna under test when the received electric field changes.

【0012】図3において1は高利得アンテナであり、
周波数f(t) の受信信号を周波数コンバーター2によっ
て周波数がf(t) −fL1の信号に変換する。周波数コン
バーター2の出力信号を分配器15によって分配し、ミキ
サー3によって周波数がfL2の局部発振器(LOSC)4の出
力と混合し、周波数がf(t) −fL1−fL2の周波数成分
をバンドバスフィルター(BPF) 5によって取り出す。分
配器15の別の出力を可変遅延時間器19によって遅延時間
を調整し、可変抵抗減衰器20によってレベル調整し、バ
ンドパスフィルター(BPF) 5の出力を分配器27によって
分配した信号とミキサー21によって混合する。得られた
L2の周波数成分をさらにミキサー22によって周波数が
L4の局部発振器(LOSC)23の出力と混合し、周波数がf
L2−fL4の周波数成分をバンドパスフィルター(BPF)24
によって雑音成分を除去し、所望の信号成分だけを取り
出す。その出力信号を包絡線検波器25によって検波し、
ローパスフィルター(LPF)26 によって直流成分を取り出
す。
In FIG. 3, 1 is a high gain antenna,
Frequency is converted into a signal f (t) -f L1 the received signal in the frequency f (t) by the frequency converter 2. The output signal of the frequency converter 2 is distributed by the distributor 15, and mixed by the mixer 3 with the output of the local oscillator (LOSC) 4 having a frequency of f L2 to generate a frequency component having a frequency of f (t) −f L1 −f L2. Take out with bandpass filter (BPF) 5. The other output of the distributor 15 has its delay time adjusted by the variable delay time device 19, its level adjusted by the variable resistance attenuator 20, and the output of the bandpass filter (BPF) 5 distributed by the distributor 27 and the mixer 21. Mix by. The obtained frequency component of f L2 is further mixed by the mixer 22 with the output of the local oscillator (LOSC) 23 having a frequency of f L4 , and the frequency is f
L2- f L4 frequency component is bandpass filter (BPF) 24
The noise component is removed by and only the desired signal component is extracted. The output signal is detected by the envelope detector 25,
The low-pass filter (LPF) 26 extracts the DC component.

【0013】7は利得基準アンテナであり、周波数f
(t) の受信信号を周波数コンバーター8によって、周波
数f(t) −fL3の信号に変換する。ただしfL3は周波数
コンバーター8の局部発振器の発振周波数である。周波
数コンバーター8の出力信号を可変遅延時間器9によっ
て遅延時間を調整し、ミキサー10によって分配器27の出
力と混合し、得られた周波数fL1+fL2−fL3の周波数
成分を、ミキサー28によって周波数がfL5の局部発振器
(LOSC)29の出力と混合し、バンドパスフィルター(BPF)3
0 によってfL1+fL2−fL3−fL5の成分だけを取り出
す。その出力信号を包絡線検波器31によって検波し、ロ
ーパスフィルター(LPF)32によって直流成分を取り出
す。次に差動増幅器33によってローパスフィルター(LP
F)26 の出力との差を取り、レベルメーター34によって
その値を指示する。この指示値が0になるように可変抵
抗減衰器20を調整した後、利得基準アンテナ7を供試ア
ンテナ13に置換し、レベルメーター34の指示値が再び0
になるように可変抵抗減衰器14を調整し、その減衰量の
増加量L(dB)を測定すると供試アンテナ13の利得G(dB)
は利得基準アンテナ7の利得をGs (dB)とすると先の式
(1) で与えられる。なお図3でミキサー22, 28での変換
はBPF 24とBPF 30の設計を容易にするためのものであ
る。
Reference numeral 7 denotes a gain reference antenna, which has a frequency f
the frequency converter 8 to receive signals (t), into a signal of a frequency f (t) -f L3. However, f L3 is the oscillation frequency of the local oscillator of the frequency converter 8. The output signal of the frequency converter 8 is adjusted in delay time by the variable delay time device 9, mixed with the output of the distributor 27 by the mixer 10, and the obtained frequency component of the frequency f L1 + f L2- f L3 is mixed by the mixer 28. Local oscillator with frequency f L5
(LOSC) 29 mixed with output, bandpass filter (BPF) 3
Only the components of f L1 + f L2 −f L3 −f L5 are extracted by 0. The output signal is detected by the envelope detector 31, and the low-pass filter (LPF) 32 extracts the DC component. Next, the low-pass filter (LP
F) The difference with the output of 26 is taken, and the value is indicated by the level meter 34. After adjusting the variable resistance attenuator 20 so that the indicated value becomes 0, the gain reference antenna 7 is replaced with the sample antenna 13, and the indicated value of the level meter 34 becomes 0 again.
Adjust the variable resistance attenuator 14 so that, and measure the increase L (dB) of the attenuation amount, the gain G (dB) of the antenna 13 under test
If the gain of the gain reference antenna 7 is G s (dB),
It is given in (1). The conversion in mixers 22 and 28 in FIG. 3 is to facilitate the design of BPF 24 and BPF 30.

【0014】図4に受信電界変動時に供試アンテナ利得
を測定する本発明方法を達成するための第4の実施例構
成ブロック線図を示す。
FIG. 4 shows a block diagram of the configuration of a fourth embodiment for achieving the method of the present invention for measuring the antenna gain under test when the received electric field changes.

【0015】図4において1は高利得アンテナであり、
周波数がf(t) の受信信号を周波数コンバーター2によ
って周波数がf(t) −fL1の信号に変換する。ただしf
L1は周波数コンバーター2の局部発振器の発振周波数で
ある。周波数コンバーター2の出力信号を分配器15によ
って二分配し、さらに分配器35によって二分配した出力
をミキサー3によって周波数がfL2の局部発振器(LOSC)
4の出力と混合し、周波数がf(t) −fL1−fL2の周波
数成分をバンドパスフィルター(BPF) 5によって取り出
す。その出力と分配器15の出力を可変遅延時間器19によ
って遅延時間を調整した出力とをミキサー21によって混
合し、周波数がfL2の周波数成分をバンドパスフィルタ
ー(BPF)36 によって取り出す。
In FIG. 4, 1 is a high gain antenna,
Frequency is the frequency by the frequency converter 2 a reception signal f (t) is converted into a signal f (t) -f L1. However f
L1 is the oscillation frequency of the local oscillator of the frequency converter 2. The output signal of the frequency converter 2 is divided into two by the divider 15, and the output divided by the divider 35 is further divided by the mixer 3 into a local oscillator (LOSC) having a frequency of f L2.
It is mixed with the output of No. 4 and the frequency component of frequency f (t) -f L1 -f L2 is taken out by the band pass filter (BPF) 5. The output and the output of the distributor 15 are mixed by the mixer 21 with the output whose delay time has been adjusted by the variable delay time device 19, and the frequency component of the frequency f L2 is taken out by the band pass filter (BPF) 36.

【0016】分配器35のもう一方の出力をミキサー22に
よって周波数がfL4の局部発振器(LOSC)23の出力と混合
し、周波数がf(t) −fL1−fL4の成分をバンドパスフ
ィルター(BPF)37 によって取り出す。7は利得基準アン
テナであり、周波数がf(t) の受信信号を周波数コンバ
ーター8によって周波数がf(t) −fL3の信号に変換す
る。ただしfL3は周波数コンバーター8の局部発振周波
数である。周波数コンバーター8の出力信号を可変遅延
時間器9によって遅延時間を調整した後、ミキーサ10に
よってバンドパスフィルター(BPF)37 の出力信号と混合
し、周波数がf L1+fL4−fL3の成分をバンドパスフィ
ルター(BPF)38 によって取り出す。位相検波器39によっ
てBPF 36とBPF 38との出力信号の位相差が一定となるよ
うに、局部発振器23の発振周波数を制御する。その結果
BPF 38の出力周波数fL1+fL4−fL3はBPF 36の出力周
波数fL2に一致する。
The other output of the distributor 35 to the mixer 22
Therefore, the frequency is fL4Local oscillator (LOSC) 23 output mixed
And the frequency is f(t)-FL1-FL4Ingredients for bandpass
Filter (BPF) 37. 7 is the gain reference
Tena, frequency f(t)Frequency conversion of the received signal of
Frequency is f(t)-FL3Signal of
It However fL3Is the local oscillation frequency of the frequency converter 8
Is a number. Variable delay of output signal of frequency converter 8
After adjusting the delay time with the time counter 9,
Therefore, it is mixed with the output signal of the bandpass filter (BPF) 37.
And the frequency is f L1+ FL4-FL3The components of the bandpass filter
Take out by Luther (BPF) 38. By the phase detector 39
The phase difference between the output signals of BPF 36 and BPF 38 becomes constant.
As described above, the oscillation frequency of the local oscillator 23 is controlled. as a result
Output frequency f of BPF 38L1+ FL4-FL3Is the output frequency of BPF 36
Wave number fL2Matches

【0017】バンドパスフィルター(BPF)36 の出力信号
を可変移相器40と可変抵抗減衰器20とによって位相と振
幅を調整し、バンドパスフィルター(BPF)38 の出力信号
と合成器41によって合成し、その出力レベルをレベル指
示器34によって指示する。合成器41の二つの入力信号が
同振幅で逆位相になるように可変移相器40と可変抵抗減
衰器20とを調整し、レベル指示器34の指示値が0になる
ようにした後、利得基準アンテナ7を供試アンテナ13に
置換し、レベル指示器34の指示値が再び0になるように
可変抵抗減衰器14を調整し、その減衰量の増加量L(dB)
を測定すると、供試アンテナ、利得基準アンテナのそれ
ぞれの利得をG(dB), Gs (dB)とすればG=Gs +Lな
る(1) 式で与えられる。
The output signal of the bandpass filter (BPF) 36 is adjusted in phase and amplitude by the variable phase shifter 40 and the variable resistance attenuator 20, and is combined with the output signal of the bandpass filter (BPF) 38 by the combiner 41. Then, the output level is indicated by the level indicator 34. After adjusting the variable phase shifter 40 and the variable resistance attenuator 20 so that the two input signals of the combiner 41 have the same amplitude and opposite phases, and the value indicated by the level indicator 34 becomes 0, The gain reference antenna 7 is replaced with the sample antenna 13, the variable resistance attenuator 14 is adjusted so that the value indicated by the level indicator 34 becomes 0 again, and the amount of increase L (dB) in the attenuation amount is adjusted.
When measured a test antenna, the respective gains of the gain reference antenna G (dB), is given by if G s (dB) becomes G = G s + L (1 ) formula.

【0018】[0018]

【発明の効果】この発明を実施することにより、周波数
変調波を無変調信号に変換することができるので、スペ
クトラムアナライザーによってレベルを測定する場合に
は測定が正確になる。また無変調信号に変換した後、周
波数変調波の帯域よりも十分狭い帯域に帯域制限するこ
とが可能となり、雑音成分を除去してC/Nを大きくす
ることができるので正確にレベルを測定することができ
る。その結果、図1に示す第1の実施例では微弱な周波
数変調波の場合でも利得基準アンテナおよび供試アンテ
ナの受信レベルを正確に測定することができ、従って供
試アンテナの利得を正確に測定することができる。
By implementing the present invention, the frequency-modulated wave can be converted into an unmodulated signal, so that the measurement becomes accurate when the level is measured by the spectrum analyzer. In addition, after converting to an unmodulated signal, it is possible to limit the band to a band sufficiently narrower than the band of the frequency modulated wave, and it is possible to remove the noise component and increase the C / N, so that the level is accurately measured. be able to. As a result, in the first embodiment shown in FIG. 1, the reception levels of the gain reference antenna and the test antenna can be accurately measured even in the case of a weak frequency modulated wave, and thus the gain of the test antenna can be accurately measured. can do.

【0019】なおアンテナの利得を測定する際には、受
信する電波の強度が時間変動しないことが必要である
が、衛星放送波の場合には衛星の姿勢変動や、大気の伝
搬特性の変動に伴って電波の強度が時間変動するので正
確な測定が不可能になる。しかし、図2に示す第2の実
施例では、利得を測定しようとするアンテナによる受信
波と別に設置したアンテナによる受信波とをスペクトラ
ムアナライザー上に同時に表示し、同一レベルになるよ
うにしてアンテナ利得の測定を行うので電波の強度が時
間変動する場合でも、その影響を除去することができ、
正確にアンテナ利得の測定をすることができる。さらに
図3に示す第3の実施例および図4に示す第4の実施例
では、利得を測定しようとするアンテナによる受信波と
別に設置したアンテナによる受信波とが同じレベルにな
るようにし、両信号のレベル差が常に0になるようにし
てアンテナ利得の測定を行なうので、電波の強度が時間
変動する場合でもその影響を除去することができ、正確
にアンテナ利得の測定をすることができる。
When measuring the gain of the antenna, it is necessary that the intensity of the received radio wave does not fluctuate over time, but in the case of satellite broadcast waves, there are variations in the attitude of the satellite and variations in the atmospheric propagation characteristics. As a result, the strength of the radio wave changes with time, making accurate measurement impossible. However, in the second embodiment shown in FIG. 2, the received wave by the antenna whose gain is to be measured and the received wave by the separately installed antenna are simultaneously displayed on the spectrum analyzer so that they are at the same level. Even if the strength of the radio wave fluctuates over time, the effect can be eliminated because
The antenna gain can be measured accurately. Furthermore, in the third embodiment shown in FIG. 3 and the fourth embodiment shown in FIG. 4, the received wave by the antenna whose gain is to be measured and the received wave by the antenna separately installed are set to the same level, Since the antenna gain is measured so that the signal level difference is always 0, the influence can be removed even when the radio wave intensity fluctuates with time, and the antenna gain can be accurately measured.

【図面の簡単な説明】[Brief description of drawings]

【図1】図1は本発明方法を達成するための第1の実施
例構成ブロック線図を示す。
FIG. 1 shows a block diagram of a first embodiment for achieving the method of the present invention.

【図2】図2は本発明方法を達成するための第2の実施
例構成ブロック線図を示す。
FIG. 2 shows a block diagram of a second embodiment for achieving the method of the present invention.

【図3】図3は本発明方法を達成するための第3の実施
例構成ブロック線図を示す。
FIG. 3 shows a block diagram of a third embodiment for achieving the method of the present invention.

【図4】図4は本発明方法を達成するための第4の実施
例構成ブロック線図を示す。
FIG. 4 shows a block diagram of a fourth embodiment for achieving the method of the present invention.

【符号の説明】[Explanation of symbols]

1 高利得アンテナ 2,8 周波数コンバーター 3,10, 21, 22, 28 ミキサー 4,23, 29 局部発振器 5,11, 24, 30, 36, 37, 38 バンドパスフィルター 6 振幅制限器 7 利得基準アンテナ 9,19 可変遅延時間器 12, 34 レベル測定器 13 供試アンテナ 14, 16, 20 可変抵抗減衰器 15, 27, 35 分配器 17, 41 合成器 18 スペクトラムアナライザー 25, 31 包絡線検波器 26, 32 ローパスフィルター 33 差動増幅器 39 位相検波器 40 可変移相器 1 High gain antenna 2,8 Frequency converter 3,10, 21, 22, 28 Mixer 4,23, 29 Local oscillator 5,11, 24, 30, 36, 37, 38 Bandpass filter 6 Amplitude limiter 7 Gain reference antenna 9, 19 Variable delay time device 12, 34 Level measurement device 13 Test antenna 14, 16, 20 Variable resistance attenuator 15, 27, 35 Distributor 17, 41 Combiner 18 Spectrum analyzer 25, 31 Envelope detector 26, 32 Low-pass filter 33 Differential amplifier 39 Phase detector 40 Variable phase shifter

Claims (1)

【特許請求の範囲】 【請求項1】 あらかじめ利得の判明している周波数変
調波を受信する第1のアンテナと、当該第1のアンテナ
より高利得でそれと同じ周波数変調波を受信する第2の
アンテナと、前記第1のアンテナの第1の受信出力およ
び前記第2のアンテナの第2の受信出力から周波数変調
成分の除去された無変調波成分を抽出するため、前記第
1の受信出力および前記第2の受信出力の少なくとも一
方に設けられた少なくとも1つの中間周波数変換手段
と、前記無変調波成分を抽出する手段と、当該抽出され
た無変調波成分から前記周波数変調波の受信レベルを求
める手段とを備えた周波数変調波の受信レベル測定装置
を用意し、はじめに前記第1のアンテナにより受信周波
数変調波の受信レベルを測定し、次に前記第1のアンテ
ナを利得未知の供試アンテナに置換してその受信レベル
を測定し、これによって前記利得未知の供試アンテナの
利得を測定するようにしたことを特徴とするアンテナの
利得測定方法。
Claim: What is claimed is: 1. A first antenna for receiving a frequency-modulated wave whose gain is known in advance, and a second antenna for receiving the same frequency-modulated wave with a higher gain than the first antenna. The first reception output of the antenna and the first reception output of the first antenna and the second reception output of the second antenna, for extracting the unmodulated wave component from which the frequency modulation component is removed, At least one intermediate frequency conversion means provided in at least one of the second reception outputs, means for extracting the non-modulation wave component, and a reception level of the frequency modulation wave from the extracted non-modulation wave component. A reception level measuring device for a frequency modulated wave having a means for obtaining is prepared, first, the reception level of the reception frequency modulated wave is measured by the first antenna, and then the first antenna. The received levels measured, whereby gain measurement method of the antenna, characterized in that so as to measure the gain of said gain unknown test antenna is replaced with a gain unknown test antenna.
JP31695891A 1991-11-29 1991-11-29 Measuring method of gain of antenna Granted JPH055764A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP31695891A JPH055764A (en) 1991-11-29 1991-11-29 Measuring method of gain of antenna

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP31695891A JPH055764A (en) 1991-11-29 1991-11-29 Measuring method of gain of antenna

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
JP20202084A Division JPS6180059A (en) 1984-09-28 1984-09-28 System for measuring intensity of electric field of frequency modulated wave

Publications (2)

Publication Number Publication Date
JPH055764A true JPH055764A (en) 1993-01-14
JPH0577988B2 JPH0577988B2 (en) 1993-10-27

Family

ID=18082835

Family Applications (1)

Application Number Title Priority Date Filing Date
JP31695891A Granted JPH055764A (en) 1991-11-29 1991-11-29 Measuring method of gain of antenna

Country Status (1)

Country Link
JP (1) JPH055764A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103242585A (en) * 2013-05-23 2013-08-14 苏州富通高新材料科技股份有限公司 Impact-resistant plastic alloy special for foaming guardrail and preparation method of plastic alloy

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103242585A (en) * 2013-05-23 2013-08-14 苏州富通高新材料科技股份有限公司 Impact-resistant plastic alloy special for foaming guardrail and preparation method of plastic alloy

Also Published As

Publication number Publication date
JPH0577988B2 (en) 1993-10-27

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