JPS60233570A - Disturbing wave measuring method - Google Patents
Disturbing wave measuring methodInfo
- Publication number
- JPS60233570A JPS60233570A JP8922284A JP8922284A JPS60233570A JP S60233570 A JPS60233570 A JP S60233570A JP 8922284 A JP8922284 A JP 8922284A JP 8922284 A JP8922284 A JP 8922284A JP S60233570 A JPS60233570 A JP S60233570A
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- Prior art keywords
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- external
- waves
- antenna
- received
- Prior art date
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- 238000000034 method Methods 0.000 title claims description 6
- 238000012360 testing method Methods 0.000 claims abstract description 17
- 230000010363 phase shift Effects 0.000 claims 1
- 230000002194 synthesizing effect Effects 0.000 abstract 1
- 238000005259 measurement Methods 0.000 description 8
- 239000002131 composite material Substances 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000000691 measurement method Methods 0.000 description 3
- 238000004891 communication Methods 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- 239000006096 absorbing agent Substances 0.000 description 1
- 238000012937 correction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 230000005672 electromagnetic field Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000002452 interceptive effect Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 230000010287 polarization Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
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- Monitoring And Testing Of Transmission In General (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明はオープンテストサイトにおいて電子機器よシ発
生する高周波電磁界強度（以下、妨害波と略称す。）を
測定する方法に関し、特に対象とする妨害波以外の放送
波や通信波等（以下。[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method for measuring the strength of high-frequency electromagnetic fields (hereinafter abbreviated as interference waves) generated by electronic equipment at open test sites, and is particularly directed to Broadcast waves and communication waves other than interference waves (hereinafter referred to as
これらの波を外来波と略称す。）を除去することにより
、混信などに起因する測定誤差をなくシ。These waves are abbreviated as foreign waves. ) eliminates measurement errors caused by interference.
測定精度を改善する方法に関するものである。This invention relates to a method for improving measurement accuracy.
オープンテストサイトにおいて電子機器より発生する妨
害波（以下、被測定波ともいう。）を測定する際、放送
用周波数帯や通信用周波数帯（１例えば、 ８０ＭＨｚ
〜３００ＭＨｚ ） （以下、これらの周波数帯を外
来周波数帯と略称す。）を含む周波数帯（例えば、 ３
０ＭＨｚ〜１’ＧＨｚ ）での測定を行なうとき、外来
周波数帯と同一または近傍での被測定波の測定が不可能
となる。When measuring interference waves generated by electronic equipment (hereinafter also referred to as measured waves) at an open test site, broadcasting frequency bands and communication frequency bands (for example, 80 MHz) are used.
~300MHz) (hereinafter, these frequency bands are abbreviated as external frequency bands) (for example, 3
When measuring at 0 MHz to 1' GHz), it is impossible to measure the wave to be measured in the same frequency band as or in the vicinity of the external frequency band.
従って、従来、可能な限シ外来波の影響を受けない土地
に測定°場を設けるか、或いは、電波吸収体及び金属遮
蔽材料を使用した所謂電波暗室を用い、外来波の侵入し
ない電磁環境を人工的に作る等の方策が計られていた。Therefore, conventional methods have been to create an electromagnetic environment in which foreign waves do not penetrate, by setting up a measurement field on land that is not affected by external waves as much as possible, or by using a so-called anechoic chamber using radio wave absorbers and metal shielding materials. Measures were taken to create it artificially.
このため、従来の方法では、測定環境の選択が必要で、
莫大な費用を要する等の欠点があった。For this reason, conventional methods require selection of the measurement environment.
There were drawbacks such as the huge cost involved.
本発明は、従来の欠点を解決するため、妨害波及び外来
波の両方の電波を受信する少なくとも２基のアンテナ、
該各アンテナの出力の振幅及び位相を相対的に変化させ
る可変振幅移相手段及び該可変振幅移相手段によって相
対的に振幅及び位相の変化された前記各アンテナの出力
を合成する混合器を有し、前記可変振幅移相手段により
前記各アンテナで受信された電波のうちの外来波を、互
いに実質上同振幅でかつ逆位相になるように調整し、前
記混合器の合成出力には前記外来波成分の除去された測
定すべき前記妨害波成分のみが合成されて出力されるよ
うにしたことを特徴とする。In order to solve the conventional drawbacks, the present invention provides at least two antennas for receiving both interference waves and external waves,
A variable amplitude phase shifter for relatively changing the amplitude and phase of the output of each of the antennas, and a mixer for combining the outputs of the antennas whose amplitudes and phases have been relatively changed by the variable amplitude phase shifter. The variable amplitude phase shifting means adjusts the external waves among the radio waves received by each of the antennas so that they have substantially the same amplitude and opposite phase, and the combined output of the mixer includes the external waves. The present invention is characterized in that only the interference wave component to be measured from which the wave component has been removed is synthesized and output.
以下９図面を参照して本発明の実施例について説明する
。Embodiments of the present invention will be described below with reference to nine drawings.
第１図を参照すると、２基のアンテナ１，２へ供試装置
（電子機器）３から発生する妨害波４ａ。Referring to FIG. 1, interference waves 4a are generated from the device under test (electronic equipment) 3 to two antennas 1 and 2.
４ｂ及び４／ａ、４１ｂと外来波５及び５′が受信され
るように、アンテナ１，２を適当な距離を隔てて配置さ
れる。なお、この適当な距離の一例については後述する
。The antennas 1 and 2 are placed at an appropriate distance so that the external waves 5 and 5' can be received by the antennas 4b, 4/a, and 41b. Note that an example of this appropriate distance will be described later.
アンテナ２にて受信された外来波５′は、まず増幅器６
で適当な値に増幅された後、移相器７において、アンテ
ナ１にて受信された外来波５と実質上逆移相になるよう
に調整される。さらに、外来波５′は、アンテナ１にて
受信された外来波５と実質上同振幅となるように、上記
増幅器６と減衰器８によって調整される。このように、
アンテナ１で受信された外来波５と実質上回振幅、逆位
相になったアンテナｉで受信された外来波５′（減衰器
８の出方信号）は、上記アンテナ１で受信された外来波
５と混合器９により合成されると９両波は互いに打ち消
され。The external wave 5' received by the antenna 2 is first transmitted to the amplifier 6.
After being amplified to an appropriate value at , it is adjusted by a phase shifter 7 so that it is substantially out of phase with the external wave 5 received by the antenna 1 . Furthermore, the external wave 5' is adjusted by the amplifier 6 and attenuator 8 so that it has substantially the same amplitude as the external wave 5 received by the antenna 1. in this way,
The external wave 5' (output signal of the attenuator 8) received by the antenna i, which has a substantially higher amplitude and opposite phase than the external wave 5 received by the antenna 1, is the external wave received by the antenna 1. When combined by wave 5 and mixer 9, both waves cancel each other.
アンテナ１で受信された妨害波４ａ、４ｂと増幅器６．
移相器７及び減衰器８により振幅と位相が変化したアン
テナ１′で受信された妨害波４′へ４’ｂとが合成され
て出力される。従って、混合器９の出力を受けるスペク
トラムアナライザーや電界強度計に代表される計測器１
ｏへは、外来波成分は出力されず、妨害波成分のみが出
力される。Interfering waves 4a, 4b received by antenna 1 and amplifier 6.
The interference waves 4' and 4'b received by the antenna 1' whose amplitude and phase have been changed by the phase shifter 7 and the attenuator 8 are combined and output. Therefore, the measuring device 1 typified by a spectrum analyzer or electric field strength meter that receives the output of the mixer 9
No external wave components are outputted to the channel o, and only interference wave components are outputted.
また、増幅器６．移相器７及び減衰器８として、マイク
ロコンピュータ等からなる制御装置１１により、計測器
１０と同時に制御を行なうことができるものを使用する
と、測定精度向上や測定時間の効率化を計ることができ
る。Also, the amplifier 6. By using a phase shifter 7 and an attenuator 8 that can be controlled simultaneously with the measuring instrument 10 by a control device 11 consisting of a microcomputer or the like, measurement accuracy can be improved and measurement time can be made more efficient. .
本装置の操作の１例としては、先ず、被試験器なる供試
装置３の電源をオフにした状態で。As an example of the operation of this device, first, the power of the device under test 3, which is the device under test, is turned off.
予め２基のアンテナ１，２で受信した外来波５，５′を
、増幅器６．移相器７及び減衰器８により。External waves 5, 5' received in advance by two antennas 1, 2 are transmitted to an amplifier 6. By phase shifter 7 and attenuator 8.
互いに打ち消すように調整しておく。この状態で、供試
装置３を動作させ、妨害波成分のみを測定する。なお、
この場合、調整可能な周波数帯域は狭帯域となるために
、調整は周波数ごとに行なう必要がある。Adjust so that they cancel each other out. In this state, the device under test 3 is operated and only the interference wave component is measured. In addition,
In this case, since the frequency band that can be adjusted is narrow, it is necessary to perform adjustment for each frequency.
次に、第２図の誘起電圧のベクトル図をも参照して９本
測定方法を論理的に説明する。Next, the nine-line measurement method will be logically explained with reference to the vector diagram of induced voltage shown in FIG.
アンテナ１で受信された妨害波４ａ、 ４ｂの誘起電圧
をそれぞれＶｌ 、 Ｖ、 、外来波５の誘起電屋を■
３とし、アンテナ２で受信された妨害波４′ａ。Let the induced voltages of interference waves 4a and 4b received by antenna 1 be Vl and V, respectively, and the induced voltage of external wave 5 as ■
3, and the interference wave 4'a received by the antenna 2.
４’ｂの誘起電圧をそ五ぞれＶ４ ＨＶ５’、外来波５
′の誘起電圧を■６とする。誘起電圧ｖ６は増幅器６゜
移相器７及び減衰器８によシ、誘起電圧Ｖ、と実質上回
振幅、逆位相の電圧ｖ６′に変換され、誘起電ＩＥ Ｖ
ａ 、Ｖａ’は混合器９にょシ合成されて打ち消し合い
、消滅する。一方、このときアンテナ２で受信された妨
害波４’ａ、 ４’ｂの誘起電圧Ｖ、、Ｖ、も、増幅器
６．移相器７及び減衰器８によシ、振幅と位相が変換さ
れて、それぞれ電圧Ｖ４’ 、 Ｖ５’となる。従って
、混合器９よシ計測器１０へ出力される電圧■は、電圧
Ｖ、、Ｖ２と電圧ｖ４’ 、 Ｖ、’との合成電圧とな
る。電圧Ｖ、 、 Ｖ２゜Ｖ３． Ｖ４． Ｖ６． Ｖ
６． Ｖ、’、″′Ｖ、′及び■の関係を以下に示す。The induced voltage of 4'b is V4 HV5', external wave 5
Let the induced voltage at ' be 6. The induced voltage v6 is converted by the amplifier 6° phase shifter 7 and attenuator 8 into a voltage v6' having an amplitude substantially higher than that of the induced voltage V and an opposite phase, and the induced voltage IE V
a and Va' are combined in the mixer 9, cancel each other out, and disappear. On the other hand, the induced voltages V, , V of the interference waves 4'a, 4'b received by the antenna 2 at this time are also applied to the amplifier 6. The amplitude and phase are converted by the phase shifter 7 and the attenuator 8, resulting in voltages V4' and V5', respectively. Therefore, the voltage (2) outputted from the mixer 9 to the measuring device 10 is a composite voltage of the voltages V, , V2 and the voltages v4', V,'. Voltage V, , V2°V3. V4. V6. V
6. The relationship between V,','''V,' and ■ is shown below.
■、トＶ２ノ位相差ψ。＝ −２ｒｃ （Ｒ２−Ｒ，）
／ λ−ｙｒ■、と■４の位相差ψ１＝−２π（ＬＩ
Ｒ１）／λ■、と■、の位相差ψ２−−２π（Ｒ２−Ｒ
１）／λ−π■３と■。の位相差ψ３−−２πＤ／λこ
こで＋ Ｒ１は供試装置３とアンテナ１への直接波の行
程距離＋ Ｒ２は供試装置３とアンテナｌへの反射波の
行程距離＋”１は供試装置３とアンテナ２への直接波の
行程距離＋ ”２は供試装置３とアンテナ２への反射波
の行程距離、λは波長。■, phase difference ψ of V2. = −2rc (R2−R,)
/ λ-yr■, and the phase difference between ■4 ψ1=-2π(LI
R1)/λ■, and the phase difference between ψ2−2π(R2−R
1)/λ−π■3 and ■. phase difference ψ3--2πD/λ where + R1 is the distance of the direct wave to the device under test 3 and antenna 1 + R2 is the distance of the reflected wave to the device under test 3 and antenna l + "1 is the distance of the direct wave to the device under test 3 and antenna l The distance of the direct wave to the test device 3 and the antenna 2 + 2 is the distance of the reflected wave to the test device 3 and the antenna 2, and λ is the wavelength.
Ｄはアンテナ１，２間の距離（路差長）をそれぞれ表わ
す。このとき９合成電圧■の大きさＩＶＩ（＝Ｖ）は９
次のようになる。D represents the distance (path difference length) between antennas 1 and 2, respectively. At this time, the magnitude IVI (=V) of 9 composite voltage ■ is 9
It will look like this:
１ｖｌ ＝（（ｖ、＋ｖ２轡。塚ｃｏｓ（ｓ−ψ３’＋
ψ、 ）＋ｖ；ｃｏｓ（ｙｒ−９’３＋９２） ’１２
＋（Ｖ２ｓｉｎψ。＋Ｖ、５ｉｎ（ｚ−ψ３＋’Ａ ）
＋ｖ、５ｉｎ（ｙｒ−ψ３＋９＋２））２］ ”以下年
日
なお、外来波のないとき、かつアンテナ１で受信した妨
害波４ａ、４ｂの誘起電圧Ｖ、 、 Ｖ２のみを、直接
計測器１０へ接続したときの誘起電圧の大きさｌ■ｌ＋
ｖ２１は。1vl = ((v, +v2轡. Tsukacos(s-ψ3'+
ψ, )+v;cos(yr-9'3+92) '12
+(V2sinψ.+V, 5in(z-ψ3+'A)
+v, 5in (yr-ψ3+9+2))2] ``When there is no external wave, only the induced voltages V, , V2 of the interference waves 4a and 4b received by the antenna 1 are connected directly to the measuring device 10. The magnitude of the induced voltage when
v21 is.
１■１＋ｖ２１＝〔（ｖ１＋ｖ２部％）２＋ （ｖ２ｓ
ｉｎψ。）２〕１′２となシ、これは通常のオープンテ
ストサイトにおける希望測定電圧となる。1■1+v21=[(v1+v2 part%)2+(v2s
inψ. )2]1'2, which is the desired voltage to be measured at a normal open test site.
次に、真値電圧ＩＶＩ＋Ｖ２１と合成電圧ＩＶＩ との
誤差について検討する。アンテナ２と供試装置３との距
離Ｌ１．Ｌ２を、アンテナ１と供試装置３との距離ＲＩ
＋Ｒ２より長くすると、受信電圧はその伝搬距離に逆比
例することによシ、電圧Ｖ４゜■、の大きさｖ、、ｖ、
を、電圧■１．■２の大きさＶ、、Ｖ２よシ小さくする
ことができる。例えば。Next, the error between the true value voltage IVI+V21 and the composite voltage IVI will be considered. Distance L1 between the antenna 2 and the device under test 3. L2 is the distance RI between the antenna 1 and the device under test 3
If it is longer than +R2, the received voltage is inversely proportional to its propagation distance, so the magnitude of the voltage V4゜■, v, , v,
, voltage ■1. (2) The size of V2 can be made smaller than V2. for example.
距離Ｌｌ＋Ｌ２を距離ＲＩ ＋ Ｒ２の６倍長くしたと
す更に、アンテナ２０指向性によるヌル点に供試装置３
の方向を合わせると、さらに約２０ｄＢ低下する（ダイ
ポールアンテナを使用した場合：水平偏波）。 このよ
うに、電圧の大きさＶ４． Ｖ。If the distance Ll + L2 is made six times longer than the distance RI + R2, furthermore, the test device 3 is placed at the null point due to the directivity of the antenna 20.
If the direction of the antenna is adjusted, the reduction will be further reduced by about 20 dB (when using a dipole antenna: horizontal polarization). Thus, the voltage magnitude V4. V.
でも、約０．３ｄＢの誤差となる。このように、アンテ
ナ距離及びアンテナ指向性を利用することにより、たと
え２基のアンテナ１，２が供試装置３からの妨害波４．
ａ、４ｂ及び４′ａ、４′ｂを受信しても、それによる
誤差を少なくすることができる。However, the error is approximately 0.3 dB. In this way, by utilizing the antenna distance and antenna directivity, even if two antennas 1 and 2 are used, interference waves 4.
Even if signals a, 4b and 4'a, 4'b are received, the resulting error can be reduced.
させなくても、予め外来波５，５′の到来方向。Even if the direction of arrival of the external waves 5, 5' is determined in advance.
周波数による誤差を測定しておくことによシ。It is best to measure the error due to frequency.
その値を補正値として扱うことができる。また。The value can be treated as a correction value. Also.
アンテナを追加することにより、 ｌＶＩ＋Ｖ２１とＩ
ＶＩとが一致するようにもできる。さらに、電係数を設
けることも可能である。By adding an antenna, lVI+V21 and I
It is also possible to match the VI. Furthermore, it is also possible to provide an electric coefficient.
以上説明したように９本発明による妨害波測定方法は、
２基以上のアンテナで妨害波及び外来波を受信しても、
アンテナの指向性等を利用することにより、測定周囲環
境における外来波を容易に除去して、妨害波成分のみを
測定することができる。よって、測定環境を特に選ぶ必
要もなく９例えば都市環境下であっても、外来波の影響
を受けることなく、妨害波の測定を行なうことが出来、
極めて有用である。As explained above, the interference wave measurement method according to the present invention is as follows:
Even if interference waves and external waves are received with two or more antennas,
By utilizing the directivity of the antenna, it is possible to easily remove external waves in the measurement surrounding environment and measure only the interference wave component. Therefore, there is no need to select a particular measurement environment.9 For example, even in an urban environment, interference waves can be measured without being affected by external waves.
Extremely useful.
第１図は本発明による妨害波測定方法を実現するための
装置の一構成例を示したブロック図。
第２図は受信信号の処理を説明するための誘起電圧ベク
トル図である。
第２図FIG. 1 is a block diagram showing an example of the configuration of an apparatus for implementing the interference wave measurement method according to the present invention. FIG. 2 is an induced voltage vector diagram for explaining processing of received signals. Figure 2
Claims (1)
る妨害波を外来波の影響をなくして測定する方法であっ
て、前記妨害波及び前記外来波の両方の電波を受信する
少なくとも２基のアンテナ、該各アンテナの出力の振幅
及び位相を相対的に変化させる可変振幅移相手段及び該
可変振幅移相手段によって相対的に振幅及び位相の変化
された前記各アンテナの出力を合成する混合器を有し、
前記可変振幅移相手段により前記各アンテナで受信され
た電波のうちの外来波を。 互いに実質上同振幅でかつ逆位相になるように調整し、
前記混合器の合成出力には前記外来波の除去された測定
すべき前記妨害波のみが合成されて出力されるようにし
たことを特徴とする妨害波測定方法。[Scope of Claims] 1. A method for measuring interference waves generated by electronic equipment at an open test site without the influence of external waves, the method comprising: receiving both the interference waves and the external waves; Two antennas, variable amplitude phase shifting means for relatively changing the amplitude and phase of the output of each antenna, and combining the outputs of the respective antennas whose amplitudes and phases have been relatively changed by the variable amplitude phase shifting means. It has a mixer that
An external wave among the radio waves received by each of the antennas by the variable amplitude phase shift means. adjusted so that they have substantially the same amplitude and opposite phases,
An interference wave measuring method characterized in that only the interference wave to be measured from which the external wave has been removed is combined and outputted as a combined output of the mixer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8922284A JPS60233570A (en) | 1984-05-07 | 1984-05-07 | Disturbing wave measuring method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8922284A JPS60233570A (en) | 1984-05-07 | 1984-05-07 | Disturbing wave measuring method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS60233570A true JPS60233570A (en) | 1985-11-20 |
Family
ID=13964698
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8922284A Pending JPS60233570A (en) | 1984-05-07 | 1984-05-07 | Disturbing wave measuring method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60233570A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02268277A (en) * | 1989-04-11 | 1990-11-01 | Yuuseishiyou Tsushin Sogo Kenkyusho | Ambient noise removal system for measurement of jamming wave |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS51144256A (en) * | 1975-06-06 | 1976-12-11 | Hitachi Ltd | Acoustic oscillatory test method and its device |
| JPS595974A (en) * | 1982-07-01 | 1984-01-12 | Mitsubishi Electric Corp | Apparatus for testing interference noise |
-
1984
- 1984-05-07 JP JP8922284A patent/JPS60233570A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS51144256A (en) * | 1975-06-06 | 1976-12-11 | Hitachi Ltd | Acoustic oscillatory test method and its device |
| JPS595974A (en) * | 1982-07-01 | 1984-01-12 | Mitsubishi Electric Corp | Apparatus for testing interference noise |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02268277A (en) * | 1989-04-11 | 1990-11-01 | Yuuseishiyou Tsushin Sogo Kenkyusho | Ambient noise removal system for measurement of jamming wave |
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