JP2839487B2 - Antenna efficiency measurement method - Google Patents
Antenna efficiency measurement methodInfo
- Publication number
- JP2839487B2 JP2839487B2 JP62047849A JP4784987A JP2839487B2 JP 2839487 B2 JP2839487 B2 JP 2839487B2 JP 62047849 A JP62047849 A JP 62047849A JP 4784987 A JP4784987 A JP 4784987A JP 2839487 B2 JP2839487 B2 JP 2839487B2
- Authority
- JP
- Japan
- Prior art keywords
- antenna
- radio wave
- measured
- reception
- receiving
- 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.)
- Expired - Fee Related
Links
Landscapes
- Aerials With Secondary Devices (AREA)
- Monitoring And Testing Of Transmission In General (AREA)
Description
【発明の詳細な説明】
〔発明の目的〕
（産業上の利用分野）
本発明は、アンテナの効率を測定するアンテナ効率測
定方法改良に関する。
（従来の技術）
携帯無線機等に内蔵された小型アンテナは、アンテナ
の近傍にある電子部品や、人体等の影響によってアンテ
ナの効率が低下する。この種の小型アンテナの評価にお
いてアンテナ効率の測定は重要なものとなる。アンテナ
効率測定方法のひとつとしてランダムフィールド法に改
良を加え、電波散乱体を用いるアンテナ効率測定方法が
従来あった。この測定方法に係わる装置を第３図に示
す。同図において、基準用の送信アンテナ12に給電する
発振器13が接続されてる。送信アンテナ12の上部を含め
た周囲には電波散乱体11が配置されている。一方送信ア
ンテナ12から送信される電波を受信する受信アンテナ14
はアーム18の先端に取着され、モータ19によってアーム
18とともに回転される。受信アンテナ14により受信され
た電波は、電界強度測定器16とマイクロコンピュータ17
によって構成される電界強度分析器15に供給される。こ
のアンテナ効率の測定は、まず基準アンテナを前記電波
散乱体11で囲まれた内部におき、発振器により給電して
電波を送信する。そして、この送信電波を、回転する受
信アンテナ14により受信し、電界強度分析器15にとり込
んで、受信確立分布として分析し、受信確立分布グラフ
を作成する。次に被測定アンテナを上記と同様に電波散
乱体11でとり囲み、同様の測定を行い受信レベルが対受
信確立分布のグラフを作成する。そして、上記２つのグ
ラフの同一確立の受信レベル差から相対的に被測定アン
テナのアンテナ効率を測定するものである。
この方法は、人工的に電波散乱体を設け電波を燦爛さ
せることにより、ランダムフィールドを作り測定精度を
あげられる効果があった。
しかし、本来アンテナ効率測定において、被測定アン
テナをどの様な方向に設定しても受信確率分布は、同一
の結果とならねばならないし、受信確率分布がレーレー
分布に近づかねばならないのに対して、従来の方法は、
このような条件の測定精度がよくなったとはいえ、まだ
まだ十分な測定精度とはいえない。
（発明が解決しようとする問題点）
上述したように、従来にのアンテナ効率測定方法で
は、被測定アンテナの設置方向によってアンテナ効率の
測定精度がよくなったとはいえ、まだまだ十分な測定精
度とはいいがたい。
そこで、本発明は、このような点に鑑みてなされたも
ので、被測定アンテナ及び基準アンテナの設定方向を変
えても、受信アテナにおける受信レベルの差を少なくす
ることができ、被測定アンテナの指向性や偏波特性によ
らず、高精度にアンテナ効率の測定を行なことができる
アンテナ効率測定方法を提供することを目的とするもの
である。
〔発明の構成〕
（問題点を解決するための手段）
本発明は、上記目的を達成するために、被測定アンテ
ナ及び基準アンテナの回りに、金属体で構成された電波
散乱体を配置し、かつ少なくとも前記電波散乱体と受信
アンテナの間に電波遮蔽幕を配置して、測定するように
したものである。
（作用）
このように本発明によると、被測定アンテナ及び基準
アンテナから送信された電波は、アンテナの回りに構成
された電波散乱体と、この電波散乱体と受信アンテナの
間に電波遮蔽幕を設けることによって、電波が散乱を受
けるため、アンテナの設置方向の影響が軽減させるとと
もに、特定の偏波が受信アンテナに強く伝搬することが
ないため、送信アンテナの方向や偏波による受信アンテ
ナへの受信レベルの偏差を減少させることができる。従
って、電波のかたよりがなく、多重反射波を受信でき
る。
（実施例）
以下図面を参照して本発明の実施例を説明する。
第１図に、本発明の一実施例を示す。同図において、
被測定用又は基準用の送信アンテナ12に、これを給電す
る発振器13が接続されている。送信アンテナ12の上部を
含めた回りには、電波散乱体11が配置され、また電波散
乱体11と受信アンテナ14との間には電波遮蔽幕が配置さ
れている。電波散乱体11は、面積、形状が任意の複数の
金属板によって構成されており、例えば、天井より吊り
下げられている。また電波遮蔽幕は、例えば金属糸を織
り込んだ布で作られ、天井よりつり下げられており送信
アンテナと受信アンテナ間で電波の直接波や反射回数の
少ない反射波などがなくて、多重反射波が伝わるように
例えば壁と壁に囲まれた部屋のすみに送信アンテナ12が
配置されていると、この一方の壁に対して垂直に設置さ
れている。
一方この送信アンテナ12から送信される電波を受信す
る受信アンテナ14は、アーム18の先端に取着され、モー
タ19によってアーム18とともに回転される。受信アンテ
ナ14により受信された電波は、電界強度測定器16とマイ
クロコンピュータ17によって構成される電界強度分析器
15に供給される。
アンテナ効率の測定にあっては、まず基準アンテナを
前記電波散乱体11で囲み、かつ電波散乱体11と受信アン
テナの14の間に電波遮断幕20を配置し、発振器13により
給電して電波を送信する。そしてこの送信電波を、回転
する受信アンテナ14により受信し、電界強度分析器15に
とり込んで受信確率分布として分析し、受信確率分布グ
ラフを作成する。次に被測定アンテナを上記と同様に電
波散乱体11でとり囲み上記と同様の配置になるよう電波
遮蔽幕20を設置し、同様の測定を行い受信レベル対受信
確率分布のグラフを作成する。そして上記２つのグラフ
の同一確率の受信レベル差から相対的に被測定アンテナ
のアンテナ効率を測定し得る。
第５図は、上記本発明の測定方法により得られた受信
レベル対受信確率分布を示す。これはアンテナの偏波を
ｚ方向、ｙ方向伸呼びｘ方向に設定した場合の特性であ
る。なおこの特性は、屋内において、受信アンテナを1.
5mのアームの先端に取着して送信アテナから15m離して
配置し、かつ送信アンテナの偏波（アンテナの方向）を
互いに直交する３つの方向に可変し、各偏波方向におい
て、合計６回、アームとともに受信アンテナを回転させ
てデータの取り込みを行なって得たものである。この測
定条件は、送信アンテナの回りに電波散乱体11を配置さ
せかつ、電波散乱体11と受信アンテナの間に電波遮蔽幕
20を配置したことにを除いて、第４図の特性測定の場合
と同一の条件である。
この第４図及び第５図の特性図から電波散乱体だけを
用いた場合、送信アンテナの方向と偏波によるレベル差
が4.9〔dB〕あったものが、本発明の方法するなわち送
信アンテナの回りに電波散乱体を配置し、電波散乱体の
受信アンテナの間に電波遮蔽幕を配置することにより、
レベル差が0.7〔dB〕程度まで改善されたことが分る。
この改善効果は、電波散乱体のみの場合に比べて大きい
ものがある。
次に、第２図に、本発明の他の実施例を示す。同図に
おいては、受信アンテナ系は第１図と同様であるので省
略している。この実施例では、内壁23と外壁24を有し、
その間に電波散乱体27を入れた非金属のキャップ30を用
意し、送信アテナ21と発振器22をキャップ30に設けられ
た空気送風口25を通して送風機28から空気を送り、電波
散乱体27を移動させ、送信アンテナ21と受信アンテナ14
の間に電波遮蔽幕29を設けたものである。このような方
法を用いると、送信アンテナから送信された電波は、電
波散乱体27と電波遮蔽幕29によって、より効果的に散乱
を受けるようになるため、上記受信レベルの差をさらに
少なくすることができる。
尚、上記実施例において、送信アンテナをとり囲む電
波散乱体は、電波は多重反射するほど、特性上は好まし
いが、発射される電波強度との関係で適宜設計され得
る。
また、上記実施例では、送信アンテナを固定し、受信
アテナを回転するように測定したが、受信アンテナを固
定し、送信アンテナを回転するようにしてもより。但
し、受信アンテナを回転するほうが構造的に簡単である
ので好ましい。
〔発明の効果〕
以上説明したように、本発明によると、被測定アンテ
ナ及び基準アンテナの回りに設けられた電波散乱体と少
なくとも電波散乱体の受信アンテナの間に設けられた電
波遮蔽幕により、被測定アンテナ及び基準アテナから送
出された電波は散乱を受けるため、被測定アンテナ及び
基準アンテナの設置方向を変化させても受信アンテナに
おける受信レベルの差を少なくすることができ、被測定
アンテナの指向性や偏波特性によらず精度の高いアンテ
ナ効率の測定が行なえる。更に電波散乱体及び電波遮蔽
幕により電波が散乱を受けるため。受信確率分布を、よ
りレーレ分布に近づけることができる。DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to an improvement in an antenna efficiency measuring method for measuring antenna efficiency. (Prior Art) The efficiency of a small antenna built in a portable wireless device or the like is reduced due to the influence of electronic components near the antenna or a human body. In the evaluation of this type of small antenna, the measurement of the antenna efficiency is important. As one of the antenna efficiency measuring methods, there has been an antenna efficiency measuring method using a radio wave scatterer by improving the random field method. FIG. 3 shows an apparatus according to this measuring method. In the figure, an oscillator 13 for feeding power to a reference transmission antenna 12 is connected. A radio scatterer 11 is arranged around the transmission antenna 12 including the upper portion. On the other hand, a receiving antenna 14 for receiving a radio wave transmitted from the transmitting antenna 12
Is attached to the tip of the arm 18 and the arm is
Rotated with 18. The electric wave received by the receiving antenna 14 is transmitted to the electric field strength measuring device 16 and the microcomputer 17.
Is supplied to the electric field intensity analyzer 15 composed of In the measurement of the antenna efficiency, first, a reference antenna is placed inside the radio wave scatterer 11, and power is supplied from an oscillator to transmit radio waves. Then, the transmitting radio wave is received by the rotating receiving antenna 14, taken into the electric field intensity analyzer 15, and analyzed as a reception probability distribution, and a reception probability distribution graph is created. Next, the antenna to be measured is surrounded by the radio wave scatterer 11 in the same manner as described above, and the same measurement is performed to create a graph of the distribution of reception level versus reception probability. Then, the antenna efficiency of the antenna to be measured is relatively measured from the reception level difference between the two graphs having the same probability. This method has the effect of creating a random field and increasing the measurement accuracy by artificially providing a radio wave scatterer and radiating radio waves. However, in the antenna efficiency measurement, the reception probability distribution must be the same regardless of the orientation of the antenna under test in any direction, and the reception probability distribution must approach the Rayleigh distribution, The traditional method is
Although the measurement accuracy under such conditions has been improved, it cannot be said that the measurement accuracy is still sufficient. (Problems to be Solved by the Invention) As described above, in the conventional antenna efficiency measurement method, although the measurement accuracy of the antenna efficiency is improved depending on the installation direction of the antenna to be measured, the sufficient measurement accuracy is still not enough. I'm sorry. Therefore, the present invention has been made in view of such a point, and even if the setting directions of the antenna under test and the reference antenna are changed, it is possible to reduce the difference in the reception level at the receiving attenuator, It is an object of the present invention to provide an antenna efficiency measuring method capable of measuring antenna efficiency with high accuracy regardless of directivity and polarization characteristics. [Configuration of the invention] (Means for solving the problems) In order to achieve the above object, the present invention arranges a radio wave scatterer made of a metal body around an antenna to be measured and a reference antenna, In addition, at least the radio wave shielding screen is arranged between the radio wave scatterer and the receiving antenna to perform measurement. (Operation) As described above, according to the present invention, the radio waves transmitted from the antenna to be measured and the reference antenna have a radio wave scatterer formed around the antenna and a radio wave shielding curtain between the radio scatterer and the reception antenna. By providing the antenna, the radio waves are scattered, and the influence of the installation direction of the antenna is reduced.In addition, since the specific polarized wave does not propagate strongly to the receiving antenna, the direction of the transmitting antenna and the polarization to the receiving antenna due to the polarized wave are reduced. The deviation of the reception level can be reduced. Therefore, it is possible to receive multiple reflected waves without any deflection of radio waves. Embodiment An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment of the present invention. In the figure,
An oscillator 13 for supplying power to the measured or reference transmitting antenna 12 is connected thereto. A radio wave scatterer 11 is arranged around the upper portion including the transmission antenna 12, and a radio wave shielding curtain is arranged between the radio wave scatterer 11 and the reception antenna 14. The radio wave scatterer 11 is formed of a plurality of metal plates having arbitrary areas and shapes, and is suspended from a ceiling, for example. In addition, the radio wave shielding curtain is made of cloth woven with metal thread, for example, and is suspended from the ceiling.There is no direct wave or reflected wave with a small number of reflections between the transmitting antenna and receiving antenna, and multiple reflected waves For example, if the transmitting antenna 12 is arranged in a corner of a room surrounded by a wall so as to transmit the signal, the antenna is installed perpendicular to the one wall. On the other hand, the receiving antenna 14 for receiving the radio wave transmitted from the transmitting antenna 12 is attached to the tip of the arm 18, and is rotated by the motor 19 together with the arm 18. The electric wave received by the receiving antenna 14 is transmitted to an electric field intensity analyzer constituted by an electric field intensity measuring device 16 and a microcomputer 17.
Supplied to 15. In measuring the antenna efficiency, first, the reference antenna is surrounded by the radio wave scatterer 11, and the radio wave shielding screen 20 is arranged between the radio wave scatterer 11 and the receiving antenna 14, and the radio wave is fed by the oscillator 13 and fed. Send. Then, the transmission radio wave is received by the rotating reception antenna 14, taken into the electric field strength analyzer 15, and analyzed as a reception probability distribution, and a reception probability distribution graph is created. Next, the antenna to be measured is surrounded by the radio wave scatterer 11 in the same manner as described above, and the radio wave shielding curtain 20 is installed so as to have the same arrangement as above, and the same measurement is performed to create a graph of the reception level versus the reception probability distribution. Then, the antenna efficiency of the antenna to be measured can be relatively measured from the reception level difference of the same probability in the two graphs. FIG. 5 shows a reception level versus reception probability distribution obtained by the above-described measurement method of the present invention. This is a characteristic when the polarization of the antenna is set in the z direction, the y direction, and the x direction. In addition, this characteristic, indoors, the receiving antenna 1.
Attached to the tip of a 5 m arm, placed 15 m away from the transmitting athena, and changed the polarization of the transmitting antenna (antenna direction) in three directions orthogonal to each other, a total of 6 times in each polarization direction , And the data is acquired by rotating the receiving antenna together with the arm. The measurement conditions are as follows: the radio wave scatterer 11 is placed around the transmission antenna, and the radio wave shielding curtain is placed between the radio scatterer 11 and the reception antenna.
The conditions are the same as those in the case of the characteristic measurement of FIG. 4, except that 20 is arranged. From the characteristic diagrams of FIGS. 4 and 5, when only the radio wave scatterer was used, the level difference due to the direction and polarization of the transmitting antenna was 4.9 [dB]. By placing a radio wave scatterer around and placing a radio wave shielding screen between the reception antennas of the radio wave scatterer,
It can be seen that the level difference has been improved to about 0.7 [dB].
This improvement effect is larger than that of the case where only the radio wave scatterer is used. Next, FIG. 2 shows another embodiment of the present invention. In the figure, the receiving antenna system is omitted because it is the same as in FIG. In this embodiment, it has an inner wall 23 and an outer wall 24,
In the meantime, prepare a non-metallic cap 30 containing the radio wave scatterer 27, send air from the blower 28 to the transmission athena 21 and the oscillator 22 through the air blowing port 25 provided in the cap 30, and move the radio wave scatterer 27. , The transmitting antenna 21 and the receiving antenna 14
A radio wave shielding curtain 29 is provided between them. When such a method is used, the radio wave transmitted from the transmitting antenna is more effectively scattered by the radio wave scatterer 27 and the radio wave shielding screen 29, so that the difference in the reception level is further reduced. Can be. In the above-described embodiment, the radio wave scatterer surrounding the transmission antenna is preferable in terms of characteristics as radio waves are reflected multiple times, but can be appropriately designed in relation to the intensity of radio waves to be emitted. Further, in the above-described embodiment, the measurement was performed such that the transmission antenna was fixed and the reception antenna was rotated. However, the reception antenna may be fixed and the transmission antenna may be rotated. However, it is preferable to rotate the receiving antenna because it is structurally simpler. [Effects of the Invention] As described above, according to the present invention, the radio wave shielding screen provided between the receiving antenna of the radio wave scatterer and at least the radio wave scatterer provided around the antenna to be measured and the reference antenna, Since the radio waves transmitted from the antenna to be measured and the reference antenna are scattered, even if the installation directions of the antenna to be measured and the reference antenna are changed, the difference in the reception level at the receiving antenna can be reduced, and the directivity of the antenna to be measured can be reduced. The antenna efficiency can be measured with high accuracy regardless of the characteristics and polarization characteristics. In addition, radio waves are scattered by radio wave scatterers and radio wave shielding curtains. The reception probability distribution can be made closer to the Rayleigh distribution.
【図面の簡単な説明】
第１図は本発明の一実施例を示す図、第２図は本発明の
他の一実施例を示す図、第３図は従来のアンテナ効率測
定法の原理図、第４図は従来の測定方法による受信レベ
ル対受信確率分布図、第５図は本発明の受信レベル対受
信確率分布図である。
11……電波散乱体
12……送信アンテナ
13……発振器
14……受信アンテナ
15……電界強度分布器
16……電界強度測定器
17……マイクロコンピュータ
18……アーム
19……モータ
20、29……電波遮蔽幕BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing one embodiment of the present invention, FIG. 2 is a diagram showing another embodiment of the present invention, and FIG. 3 is a principle diagram of a conventional antenna efficiency measuring method. FIG. 4 is a distribution diagram of reception level versus reception probability according to the conventional measuring method, and FIG. 5 is a distribution diagram of reception level versus reception probability according to the present invention. 11 radio wave scatterer 12 transmitting antenna 13 oscillator 14 receiving antenna 15 electric field intensity distributor 16 electric field intensity measuring device 17 microcomputer 18 arm 19 motors 20 and 29 …… Electromagnetic shielding
Claims (1)
アンテナを各々の軸方向に固定した際に放射された電波
をその基準アンテナの位置に対して相対的に所定の経路
で移動する受信アンテナでそれぞれ受信することにより
基準となる電波の受信電界強度を観測した後、前記３軸
方向に固定可能な被測定アンテナを各々の軸方向に固定
した際に放射された電波をその被測定アンテナの位置に
対して相対的に所定の経路で移動する受信アンテナで受
信することにより被測定アンテナから放射された電波の
受信電界強度を観測し、前記基準電波の受信電界強度の
観測結果と前記被測定アンテナから放射された電波の受
信電界強度の観測結果とから被測定アンテナの放射効率
を求めるアンテナ効率測定方法において、 前記基準アンテナの周囲に複数の電波散乱体を設け、か
つ前記電波散乱体と前記受信アンテナとの間に電波遮蔽
幕を設け、前記の電波の受信強度を測定した後、前記基
準アンテナを前記被測定アンテナに置き換えて前記被測
定アンテナから放射された前記電波の受信強度を観測す
ることを特徴とするアンテナ効率測定方法。(57) [Claims] Radio waves radiated when the reference antennas that can be fixed in three axial directions that are spatially orthogonal to each other are fixed in each axial direction are receiving antennas that move along a predetermined path relatively to the position of the reference antenna. After observing the received electric field strength of the reference radio wave by receiving each, the radio waves radiated when the antennas to be measured that can be fixed in the three axial directions are fixed in the respective axial directions are represented by the positions of the measured antennas. The reception electric field strength of the radio wave radiated from the antenna to be measured is observed by receiving the signal with the reception antenna moving on a predetermined route relatively to the antenna, and the observation result of the reception electric field strength of the reference radio wave and the antenna to be measured are received. An antenna efficiency measuring method for obtaining a radiation efficiency of an antenna to be measured from an observation result of a received electric field strength of a radio wave radiated from a plurality of antennas. A wave scatterer is provided, and a radio wave shielding screen is provided between the radio wave scatterer and the receiving antenna, and after measuring the reception intensity of the radio wave, the reference antenna is replaced with the antenna to be measured, and the measurement is performed. An antenna efficiency measuring method characterized by observing the reception intensity of the radio wave radiated from an antenna.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62047849A JP2839487B2 (en) | 1987-03-04 | 1987-03-04 | Antenna efficiency measurement method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62047849A JP2839487B2 (en) | 1987-03-04 | 1987-03-04 | Antenna efficiency measurement method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63215971A JPS63215971A (en) | 1988-09-08 |
| JP2839487B2 true JP2839487B2 (en) | 1998-12-16 |
Family
ID=12786814
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62047849A Expired - Fee Related JP2839487B2 (en) | 1987-03-04 | 1987-03-04 | Antenna efficiency measurement method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2839487B2 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02120915A (en) * | 1988-10-31 | 1990-05-08 | Toshiba Corp | Switching power supply |
| FR2906040B1 (en) * | 2006-09-14 | 2009-03-20 | Eads Ccr Groupement D Interet | REVERBERANT ROOM |
| FR2917835B1 (en) * | 2007-06-22 | 2009-08-28 | Thales Sa | DEVICE AND METHOD FOR MEASURING THE TWO POLARIZATIONS OF AN ELECTROMAGNETIC FIELD PRODUCED BY A SOURCE, IN PARTICULAR AN ANTENNA |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58168970A (en) * | 1982-03-30 | 1983-10-05 | Toshiba Corp | Measuring method of antenna efficiency |
-
1987
- 1987-03-04 JP JP62047849A patent/JP2839487B2/en not_active Expired - Fee Related
Non-Patent Citations (1)
| Title |
|---|
| 電子通信学会技術研究報告Ｖｏｌ．８６，Ｎｏ．２３０ ｐｐ．５１−５８（１９８６） |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63215971A (en) | 1988-09-08 |
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