JPH10242748A - Multi-path prevention fence - Google Patents
Multi-path prevention fenceInfo
- Publication number
- JPH10242748A JPH10242748A JP4311697A JP4311697A JPH10242748A JP H10242748 A JPH10242748 A JP H10242748A JP 4311697 A JP4311697 A JP 4311697A JP 4311697 A JP4311697 A JP 4311697A JP H10242748 A JPH10242748 A JP H10242748A
- Authority
- JP
- Japan
- Prior art keywords
- station antenna
- base station
- fence
- ceiling
- 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.)
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- Aerials With Secondary Devices (AREA)
- Mobile Radio Communication Systems (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は屋内高速無線通信装
置に関し、壁、床、天井からの反射によるマルチパスフ
ェージングを軽減し、誤り率（ＢＥＲ）、Ｄ／Ｕ（希望
波と干渉波の比）を改善した高品質な伝送を可能とする
屋内高速無線通信装置に係る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an indoor high-speed wireless communication apparatus, which reduces multipath fading caused by reflection from walls, floors, and ceilings, and has an error rate (BER), D / U (ratio between a desired wave and an interference wave). The present invention relates to an indoor high-speed wireless communication device that enables high-quality transmission with improved).
【０００２】[0002]
【従来の技術】図４は、従来の屋内高速無線通信装置と
短遅延の干渉波の伝搬経路を示す図である。同図におい
て、数字符号１は床、２は基地局アンテナ背後の壁、３
は端局アンテナの背後の壁、４は天井、５は基地局装
置、６は端末装置、７は基地局アンテナ、８は端局アン
テナ、９は基地局アンテナの垂直面内における放射パタ
ーン、１０は端局アンテナの垂直面内における放射パタ
ーンを示している。2. Description of the Related Art FIG. 4 is a diagram showing a conventional indoor high-speed wireless communication apparatus and a propagation path of a short-delay interference wave. In the figure, numeral 1 is a floor, 2 is a wall behind a base station antenna, 3
Is a wall behind the terminal station antenna, 4 is a ceiling, 5 is a base station device, 6 is a terminal device, 7 is a base station antenna, 8 is a terminal station antenna, 9 is a radiation pattern in a vertical plane of the base station antenna, 10 Indicates a radiation pattern in a vertical plane of the terminal station antenna.
【０００３】また、１７は基地局アンテナから直接、端
末アンテナに到来する波の伝搬経路、１８は基地局アン
テナより放射し、床に反射した後、端末アンテナに到来
する波の伝搬経路、１９は基地局アンテナより放射し、
天井で反射した後、端末アンテナに到来する波の伝搬経
路である。Further, 17 is a propagation path of a wave arriving directly at the terminal antenna from the base station antenna, 18 is a propagation path of a wave radiated from the base station antenna and reflected on the floor and arriving at the terminal antenna, 19 is Radiate from the base station antenna,
This is the propagation path of the wave that arrives at the terminal antenna after being reflected on the ceiling.
【０００４】基地局アンテナ７は天井高と同程度、また
はそれよりも低い高さに設置され、部屋の端に設置され
た端末局アンテナ８と通信を行う。基地局アンテナの垂
直面内放射パターンは、基地局アンテナの垂直面内にお
ける放射パターンのピークが端末局アンテナの方向と一
致するように水平方向から下方に傾けられている。[0004] A base station antenna 7 is installed at a height approximately equal to or lower than the ceiling height, and communicates with a terminal station antenna 8 installed at an end of a room. The radiation pattern in the vertical plane of the base station antenna is inclined downward from the horizontal direction so that the peak of the radiation pattern in the vertical plane of the base station antenna coincides with the direction of the terminal station antenna.
【０００５】基地局アンテナ７から端末局アンテナ８へ
到来する波としては、基地局アンテナ７から放射された
後、直接、端末基地局アンテナ８に到来する直接波以外
に、基地局アンテナ７より放射され、床１に反射した
後、端末局アンテナ８に到来する波、及び基地局アンテ
ナ７より放射され、天井４で反射した後、端末局アンテ
ナ８に到来する波がある。The waves arriving from the base station antenna 7 to the terminal station antenna 8 are radiated from the base station antenna 7 in addition to the direct waves arriving at the terminal base station antenna 8 after being radiated from the base station antenna 7. Then, there is a wave arriving at the terminal station antenna 8 after being reflected on the floor 1 and a wave radiated from the base station antenna 7 and arriving at the terminal station antenna 8 after being reflected on the ceiling 4.
【０００６】これらの波は基地局アンテナ７から直接端
末局アンテナ８に到来する波の伝搬時間との差（これを
遅延時間と呼ぶ）が短い、いわゆる短遅延の干渉波であ
る。一方、図５は従来の屋内高速通信無線装置と長遅延
の干渉波の伝搬経路を示す図である。基地局アンテナか
らの放射指向性は、対向する端末局アンテナのみならず
端末局アンテナ背後の壁や天井にも向けられている。[0006] These waves are so-called short-delay interference waves having a short difference from the propagation time of a wave arriving directly from the base station antenna 7 to the terminal station antenna 8 (this is called a delay time). On the other hand, FIG. 5 is a diagram showing a conventional indoor high-speed communication radio apparatus and a propagation path of a long-delay interference wave. The radiation directivity from the base station antenna is directed not only to the terminal station antenna facing the terminal station but also to the wall or ceiling behind the terminal station antenna.
【０００７】このため、基地局アンテナ７から端末局ア
ンテナ８へ到来する波としては、２３の基地局アンテナ
から放射され、端末局アンテナ背後の壁で反射し、基地
局アンテナ背後の壁で再び反射した後、端末局アンテナ
に到来する波、及び２４の基地局アンテナ近傍の天井に
反射し、端末局アンテナ背後の壁で反射し、さらに基地
局アンテナ背後の壁で再び反射した後、端末局アンテナ
に到来する波が存在する。これらの波は、いわゆる長遅
延の干渉波である。For this reason, waves arriving from the base station antenna 7 to the terminal station antenna 8 are radiated from the 23 base station antennas, reflected on the wall behind the terminal station antenna, and reflected again on the wall behind the base station antenna. After that, the wave arriving at the terminal station antenna, reflected on the ceiling near the base station antenna of 24, reflected on the wall behind the terminal station antenna, and again reflected on the wall behind the base station antenna, There is a wave arriving at. These waves are so-called long delay interference waves.
【０００８】このため、屋内高速無線通信装置では、短
遅延の干渉波である床や天井、側壁による１回反射波の
干渉により受信レベルが低下した状態にさらに長遅延の
干渉波である端末局アンテナ背後の壁と基地局アンテナ
背後の壁でそれぞれ反射した２回以上反射した反射波と
が干渉し、符号誤りを発生させ、伝送特性を劣化させて
いる。For this reason, in the indoor high-speed radio communication apparatus, the terminal station antenna which is a longer delay interference wave is in a state where the reception level is lowered due to the interference of the once reflected wave by the floor, ceiling and side walls which are short delay interference waves. The reflected waves reflected two or more times at the wall behind the base station and at the wall behind the base station antenna interfere with each other, causing a code error and deteriorating the transmission characteristics.
【０００９】すなわち、伝送速度が数１０Ｍbit／sにも
達する準ミリ波、ミリ波帯を使った屋内高速ディジタル
伝送では、干渉波の遅延時間がシンボル長と同程度とな
り、干渉波の遅延時間がシンボル長の内外に存在する。
このような屋内マルチパス環境下では、符号誤り率は干
渉波の遅延時間には依存せず、希望波の干渉レベル
（Ｄ）と干渉波の全干渉レベル（Ｕ）との比（Ｄ／Ｕ）
により決定される。That is, in indoor high-speed digital transmission using a quasi-millimeter wave band and a millimeter wave band whose transmission speed reaches several tens of Mbit / s, the delay time of the interference wave becomes almost equal to the symbol length, and the delay time of the interference wave becomes It exists inside and outside the symbol length.
In such an indoor multipath environment, the bit error rate does not depend on the delay time of the interference wave, and the ratio (D / U) of the interference level (D) of the desired wave to the total interference level (U) of the interference wave )
Is determined by
【００１０】このため、伝送速度が数１０Ｍbit／sにも
達するミリ波帯での屋内高速ディジタル伝送では、多数
の干渉波に対する所望波のＤ／Ｕを改善することが屋内
高速通信の実現の基本といえる。（文献：中山，佐藤，
吉田：“ミリ波による屋内高速伝送特性”，信学論
（Ｂ), vol.77-C-I,no.11,pp.640-647，Nov.1994参照）For this reason, in indoor high-speed digital transmission in the millimeter wave band where the transmission speed reaches several tens of Mbit / s, it is essential to improve the D / U of a desired wave against a large number of interference waves. It can be said that. (Literature: Nakayama, Sato,
Yoshida: "Indoor high-speed transmission characteristics using millimeter waves", IEICE (B), vol.77-CI, no.11, pp.640-647, Nov.1994)
【００１１】[0011]
【発明が解決しようとする課題】このような、端末局ア
ンテナと基地局アンテナの背後の壁でそれぞれ反射した
２回以上反射した反射波の干渉による伝送特性の劣化を
改善するためには、垂直面内放射パターンにおいて、基
地局アンテナからみて対向する壁や天井を見込む角度に
ヌル点を形成することにより、対向する壁や天井からの
反射波を全て抑圧すれば、干渉波に対するＤ／Ｕを改善
できることは容易に考えられる。In order to improve the deterioration of the transmission characteristics due to the interference of the reflected waves reflected two or more times on the walls behind the terminal station antenna and the base station antenna, it is necessary to use a vertical antenna. In the in-plane radiation pattern, by forming a null point at an angle that looks into the opposing wall or ceiling when viewed from the base station antenna, all the reflected waves from the opposing wall or ceiling are suppressed, and the D / U for the interference wave can be reduced. It is easy to think that it can be improved.
【００１２】この条件を満足する放射パターン形状のア
ンテナを実現するアンテナの一例として垂直面内の放射
パターンがコセカント２乗の形状を持つ、いわゆるコセ
カント２乗成形ビームアンテナ等が考案されている。As an example of an antenna for realizing an antenna having a radiation pattern that satisfies this condition, a so-called cosecant square shaped beam antenna having a cosecant square radiation pattern in a vertical plane has been proposed.
【００１３】しかし、成形ビームアンテナで所望の放射
パターンを実現するためには、少なくとも数１０素子の
素子アンテナが必要であることから、給電回路を含めた
アンテナ装置全体が非常に大きくなるという難点があっ
た。また、成形ビームアンテナでは素子間の励振振幅の
比が大きくなることから、製造精度による誤差が無視で
きなくなり、特にミリ波帯では製造精度の影響が顕著に
なり、所望の性能を実現することが困難になるという課
題があった。However, in order to realize a desired radiation pattern with a shaped beam antenna, at least several tens of element antennas are required, so that the whole antenna device including the feed circuit becomes very large. there were. In addition, in the shaped beam antenna, since the ratio of the excitation amplitude between the elements becomes large, the error due to the manufacturing accuracy cannot be ignored. Particularly, in the millimeter wave band, the effect of the manufacturing accuracy becomes remarkable, and the desired performance can be realized. There was a problem that it became difficult.
【００１４】以上説明したように、従来の屋内無線通信
装置では、基地局アンテナとして成形ビームアンテナを
用いていたため、アレーを構成する素子数が多くなり、
アンテナ装置全体が大きくなる問題があり、これに加
え、アンテナ装置の製作及び所望の性能の実現が困難に
なるという問題があった。As described above, in the conventional indoor radio communication device, since the shaped beam antenna is used as the base station antenna, the number of elements constituting the array increases,
There is a problem that the whole antenna device becomes large, and in addition to this, there is a problem that it is difficult to manufacture the antenna device and to achieve desired performance.
【００１５】本発明は、このような従来の課題を解決す
るために成されたもので、屋内高速無線通信装置におい
て、受信アンテナ背後の壁や天井からの２回以上反射波
を抑圧し、長遅延反射波によるマルチパスフェージング
を低減させ、希望波の干渉レベル（Ｄ）と干渉波の全干
渉レベル（Ｕ）との比（Ｄ／Ｕ）を大きく改善すること
のできる高品質な屋内無線通信を、簡易なアンテナ構成
の無線通信装置で実現することを目的とする。SUMMARY OF THE INVENTION The present invention has been made to solve such a conventional problem. In an indoor high-speed wireless communication apparatus, a reflected wave from a wall or a ceiling behind a receiving antenna is suppressed two or more times, and a long signal is transmitted. High quality indoor wireless communication that can reduce multipath fading due to a delayed reflected wave and greatly improve the ratio (D / U) of the interference level (D) of the desired wave to the total interference level (U) of the interference wave Is realized by a wireless communication device having a simple antenna configuration.
【００１６】[0016]
【課題を解決するための手段】本発明によれば、上述の
課題は前記特許請求の範囲に記載した手段により解決さ
れる。すなわち、請求項１の発明は、少なくとも１つの
基地局と少なくとも１つの端末局の間で通信を行う屋内
無線通信装置において、部屋の天井の高さをＨ、床から
端末局アンテナまでの高さをＨｒ、基地局アンテナと天
井の距離をＨｔ、基地局アンテナから水平面においてＸ
軸に対する角度がφの方向の壁までの距離をＤφとする
とき、According to the present invention, the above-mentioned object is solved by the means described in the claims. That is, the invention according to claim 1 is an indoor wireless communication apparatus that performs communication between at least one base station and at least one terminal station, wherein the height of the ceiling of the room is H and the height from the floor to the terminal station antenna. Is Hr, the distance between the base station antenna and the ceiling is Ht, and X
When the distance to the wall in the direction where the angle to the axis is φ is Dφ,
【００１７】水平面から下方に前記“数１”で示す式
（１）で与えられるθｄφの範囲の電波を、無線基地局
アンテナを包囲する、電波遮蔽体等の電波を吸収もしく
は反射して透過させない材質で構成したフェンスで遮る
と共に、基地局アンテナからφ方向のフェンスまでの距
離をＲφとするとき、フェンスの天井からの垂直下方高
が、ほぼ、前記式（２）を満足するマルチパス防止フェ
ンスである。A radio wave in the range of θdφ given by the equation (1) expressed by the above formula 1 below the horizontal plane is absorbed or reflected by a radio wave shield or the like surrounding the radio base station antenna and is not transmitted. When the distance from the base station antenna to the fence in the φ direction is Rφ, the vertical lower height from the ceiling of the fence substantially satisfies the above formula (2), while blocking with a fence made of a material. It is.
【００１８】請求項２の発明は、上記請求項１の発明に
おいて、Ｘ軸からの角度φに依らずＲφを一定値にし基
地局アンテナを中心とする水平面の円周上にフェンスを
配置し、基地局アンテナからの方向φに依らず、電波の
フェンスへ水平面の入射角が９０度となるように構成し
たものである。According to a second aspect of the present invention, in the first aspect of the present invention, a fence is arranged on a circumference of a horizontal plane centered on a base station antenna with Rφ being constant regardless of the angle φ from the X axis. The configuration is such that the angle of incidence of the radio wave on the horizontal plane is 90 degrees regardless of the direction φ from the base station antenna.
【００１９】請求項３の発明は、請求項１、または、請
求項２記載の発明において、前記式（２）の特殊な解と
して与えられる方向φに依らずフェンスの高さＨφが一
定となる部屋の水平断面形状の極座標（φ，Ｄφ）と前
記式（３）の関係を持つ部屋の水平断面と相似形の水平
面フェンス配列（φ，Ｒφ′）で、フェンスの方向φの
厚みＴが（Ｒφ′−Ｒφ）であるように構成したもので
ある。According to a third aspect of the present invention, in the first or the second aspect of the present invention, the height Hφ of the fence is constant irrespective of the direction φ given as a special solution of the equation (2). In the horizontal fence arrangement (φ, Rφ ′) similar to the horizontal cross section of the room having the relationship of the above equation (3) with the polar coordinates (φ, Dφ) of the horizontal cross section of the room, the thickness T in the direction φ of the fence is ( Rφ′−Rφ).
【００２０】請求項４の発明は、請求項１〜請求項３記
載の発明において、基地局アンテナを囲むマルチパス防
止フェンスに囲まれた範囲の内側の天井に電波を吸収す
る材質の板状パネルを配置したものである。According to a fourth aspect of the present invention, in the first to third aspects of the present invention, a plate-like panel made of a material absorbing radio waves is provided on a ceiling inside a range surrounded by a multipath prevention fence surrounding a base station antenna. Is arranged.
【００２１】請求項５の発明は、請求項１〜請求項４記
載の発明において、基地局アンテナを囲むマルチパス防
止フェンスに囲まれる範囲の側壁に電波を吸収する材質
の板状パネルを配置したものである。According to a fifth aspect of the present invention, in the first to fourth aspects of the present invention, a plate-like panel made of a material for absorbing radio waves is disposed on a side wall in a range surrounded by a multipath prevention fence surrounding the base station antenna. Things.
【００２２】本発明は、上述のように、少なくとも１つ
の基地局と少なくとも１つの端末局の間で通信を行う屋
内無線通信において、部屋の形状と大きさ、基地局設置
位置等によって変化する抑圧すべき２回以上反射した反
射波が含まれる長遅延波の放射角の範囲を、抑圧しては
いけない基地局アンテナから放射され、直接、端末局ア
ンテナに到来する直接波の基地局アンテナからの放射角
を基準境界として範囲の特定を行うものである。According to the present invention, as described above, in indoor wireless communication in which communication is performed between at least one base station and at least one terminal station, suppression that varies depending on the shape and size of the room, the installation position of the base station, and the like. The range of the radiation angle of the long delay wave including the reflected wave which should be reflected two or more times should not be suppressed. The direct wave from the base station antenna which is radiated from the base station antenna and directly arrives at the terminal station antenna The range is specified using the radiation angle as a reference boundary.
【００２３】部屋の幅Ｌｘ、奥行きＬｙ、天井の高さを
Ｈ、床から端末局アンテナまでの高さをＨｒ、基地局ア
ンテナと天井の距離をＨｔ、基地局アンテナと部屋の基
準対向壁面までの距離をＸ、基地局アンテナと部屋の基
準側壁面までの距離をＹ、基地局アンテナからの方向を
φ、基地局アンテナからφ方向の壁までの距離のＤφよ
り、The width Lx and depth Ly of the room, the height of the ceiling is H, the height from the floor to the terminal station antenna is Hr, the distance between the base station antenna and the ceiling is Ht, and the distance between the base station antenna and the reference opposed wall surface of the room is Ht. X is the distance between the base station antenna and the reference side wall surface of the room, Y is the direction from the base station antenna, and D is the distance from the base station antenna to the wall in the φ direction.
【００２４】基地局アンテナからφ方向の屋内最遠点で
の直接波の垂直面放射角のθｄφを求めると、抑圧して
はいけない放射角の範囲は基地局アンテナから水平面φ
方向の屋内最遠点への直接波の垂直面放射角のθｄφを
含む下方の範囲となり、逆に抑圧すべき放射角の範囲は
基地局アンテナから水平面φ方向の屋内最遠点での直接
波の垂直面放射角のθｄφより上方の範囲となる。When the vertical plane radiation angle θdφ of the direct wave at the farthest point in the indoor in the φ direction from the base station antenna is obtained, the range of the radiation angle that must not be suppressed is the horizontal plane φ from the base station antenna.
Is the lower range including the vertical plane radiation angle θdφ of the direct wave to the farthest point indoors in the direction, and the range of the radiation angle to be suppressed is the direct wave at the farthest point indoors in the horizontal φ direction from the base station antenna. Above the vertical plane radiation angle θdφ.
【００２５】基地局アンテナを囲むように電波を透過さ
せない材質のフェンスを天井等に配置し、基地局アンテ
ナから垂直面放射角のθｄφより上方に放射された、マ
ルチパス干渉の原因となる電波を伝搬経路上で吸収、減
衰、遮断することにより抑圧し、基地局アンテナでビー
ム成形を行わず、対向する壁や天井からの反射波を抑圧
し、Ｄ／Ｕを改善できる。この点が本発明と従来技術が
異なる点である。A fence made of a material that does not transmit radio waves is placed on the ceiling or the like so as to surround the base station antenna, and radio waves that are emitted from the base station antenna above the vertical plane radiation angle θdφ and cause multipath interference are disposed. Suppression is achieved by absorbing, attenuating, and blocking on the propagation path, and the reflected wave from the opposing wall or ceiling can be suppressed without performing beam shaping by the base station antenna, and D / U can be improved. This is the difference between the present invention and the prior art.
【００２６】すなわち、本発明は、基地局アンテナのビ
ーム成形をアンテナ本体でなく、室内に設置したフェン
スによる遮蔽で行い、例えばホーンアンテナ等の非常に
簡易な構成の基地局アンテナを備えた無線通信装置自体
を改良することなく屋内高速無線通信の課題を克服する
ものである。That is, according to the present invention, the beam shaping of the base station antenna is performed not by the antenna body but by the fence installed in the room, and for example, the radio communication provided with a very simple base station antenna such as a horn antenna. The object of the present invention is to overcome the problem of indoor high-speed wireless communication without improving the device itself.
【００２７】[0027]
【発明の実施の形態】以下、本発明の実施の形態の例を
図に基づいて説明する。図１は本発明の実施の形態の第
１の例を示す図である。同図において、数字符号１は
床、２は基地局アンテナ背後の壁、３は端末局アンテナ
背後の壁、４は天井、５は基地局装置、６は端末局装
置、７は基地局アンテナ、８は端末局アンテナ、９は基
地局アンテナの垂直面内における放射パターンを表わし
ている。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a first example of an embodiment of the present invention. In the figure, numeral 1 indicates a floor, 2 indicates a wall behind a base station antenna, 3 indicates a wall behind a terminal station antenna, 4 indicates a ceiling, 5 indicates a base station apparatus, 6 indicates a terminal station apparatus, 7 indicates a base station antenna, Reference numeral 8 denotes a terminal station antenna, and 9 denotes a radiation pattern in a vertical plane of the base station antenna.
【００２８】また、１０は端末局アンテナの垂直面内に
おける放射パターン、１３は電波を遮断する材質のフェ
ンス、１７は基地局アンテナから直接、端末局アンテナ
に到来する波の伝搬経路、１８は基地局アンテナより放
射し、床に反射した後、端末局アンテナに到来する波の
伝搬経路を示している。Numeral 10 is a radiation pattern in the vertical plane of the terminal station antenna, 13 is a fence made of a material that blocks radio waves, 17 is a propagation path of a wave arriving at the terminal station antenna directly from the base station antenna, and 18 is a base station. It shows a propagation path of a wave radiated from the station antenna and reflected on the floor, and then arriving at the terminal station antenna.
【００２９】また、２０は基地局アンテナより放射し、
天井で反射した後、端末局アンテナに到来する波の伝搬
経路のフェンスによる遮蔽、２１は基地局アンテナよ
り、端末局アンテナ背後の壁３に反射し、基地局アンテ
ナ背後の壁２に反射した後、端末局アンテナに到来する
波の伝搬経路のフェンスによる遮蔽、２２は基地局アン
テナより天井４で反射し、端末局アンテナ背後の壁３に
反射し、さらに基地局アンテナ背後の壁２に反射した
後、端末局アンテナに到来する波の伝搬経路のフェンス
による遮蔽を表わしている。Also, 20 radiates from the base station antenna,
After being reflected by the ceiling, the fence of the propagation path of the wave arriving at the terminal station antenna is shielded by a fence. 21 is reflected from the base station antenna to the wall 3 behind the terminal station antenna and to the wall 2 behind the base station antenna. , The fence of the propagation path of the wave arriving at the terminal station antenna is reflected by the ceiling 4 from the base station antenna, reflected on the wall 3 behind the terminal station antenna, and further reflected on the wall 2 behind the base station antenna. Later, the fence of the wave arriving at the terminal station antenna is shielded by a fence.
【００３０】図２は本発明のマルチパス防止フェンスが
遮蔽すべき角度の定式化を説明する図である。図２
（ａ）の水平面図において、Ｌｘは部屋の幅、Ｌｙは奥
行き、Ｘは基地局アンテナと部屋の基準対向壁面までの
距離、Ｙは基地局アンテナと部屋の基準側壁までの距
離、φはＸ軸からの水平方向、Ｄφは基地局アンテナか
ら水平面φ方向の壁までの水平距離である。FIG. 2 is a diagram for explaining the formulation of the angle to be shielded by the multipath prevention fence of the present invention. FIG.
In the horizontal plan view of (a), Lx is the width of the room, Ly is the depth, X is the distance between the base station antenna and the reference facing wall surface of the room, Y is the distance between the base station antenna and the reference side wall of the room, and φ is X The horizontal direction from the axis, Dφ, is the horizontal distance from the base station antenna to the wall in the horizontal φ direction.
【００３１】特に、方形の室内の場合の極座標（φ，Ｄ
φ）は、極座標原点から見た四隅の角度をφ1、φ2、φ
3、φ4で表わすと、平面座標（ｘ，ｙ）で以下の“数
２”で示す式（４）〜式（７）ように表わせる。但し、
０°＜φ1＜９０°＜φ2＜１８０°＜φ3＜２７０°＜
φ4＜３６０°である。In particular, polar coordinates (φ, D
φ) is the angles of the four corners as viewed from the polar coordinate origin, φ 1 , φ 2 , φ
3, expressed in phi 4, Equation (4) shown by the following "Formula 2" in plane coordinates (x, y) ~ (7) as represented. However,
0 ° <φ 1 <90 ° <φ 2 <180 ° <φ 3 <270 ° <
φ 4 <360 °.
【００３２】[0032]
【数２】 (Equation 2)
【００３３】またＤφは、φの大きさによって、“数
３”で示す式（８）〜式（１１）のように表わせる。す
なわち、０°≦φ＜φ1及びφ4≦φ＜３６０°の場合は
（８）式、φ1≦φ＜φ2の場合は（９）式、φ2≦φ＜
φ3の場合は（１０）式、φ3≦φ＜φ4の場合は（１
１）式のように表わせる。Further, Dφ can be expressed as shown in Expressions (8) to (11) represented by “Equation 3” according to the size of φ. That is, when 0 ° ≦ φ <φ 1 and φ 4 ≦ φ <360 °, the expression (8) is used, when φ 1 ≦ φ <φ 2 is the expression (9), φ 2 ≦ φ <
For phi 3 (10) wherein in the case of φ 3 ≦ φ <φ 4 ( 1
It can be expressed as in equation (1).
【００３４】[0034]
【数３】 (Equation 3)
【００３５】図２（ｂ）は基地局からφ方向の垂直断面
図である。Ｈは天井の高さ、Ｈｒは床から端末局アンテ
ナまでの高さ、Ｈｔは基地局アンテナと天井の距離、Ｄ
φは基地局アンテナから水平面φ方向の壁までの水平距
離、θｄφは基地局アンテナから水平φ方向の屋内最遠
点へ届く直接波の放射角のθｄφである。θｄφは“数
４”で示す式（１２）のように表わされる。FIG. 2B is a vertical sectional view in the φ direction from the base station. H is the height of the ceiling, Hr is the height from the floor to the terminal station antenna, Ht is the distance between the base station antenna and the ceiling, D
φ is the horizontal distance from the base station antenna to the wall in the horizontal φ direction, and θdφ is the radiation angle θdφ of the direct wave reaching the indoor farthest point in the horizontal φ direction from the base station antenna. θdφ is expressed as Expression (12) shown by “Equation 4”.
【００３６】[0036]
【数４】 (Equation 4)
【００３７】図３は本発明の実施の形態の第１の例の遮
蔽に使用するフェンスの高さの定式化を説明する図であ
って、基地局からφ方向の垂直断面図を示している。λ
は送信波長、Ｈφは第一フレネル半径を考慮したフェン
スの天井からの垂直下方高、Ｒφは基地局アンテナから
φ方向のマルチパス防止フェンスまでの距離でＲφを満
足する値を使用する。FIG. 3 is a diagram for explaining the formulation of the height of the fence used for shielding in the first example of the embodiment of the present invention, and shows a vertical sectional view in the φ direction from the base station. . λ
Is the transmission wavelength, Hφ is the vertical lower height from the ceiling of the fence considering the first Fresnel radius, and Rφ is a value that satisfies Rφ by the distance from the base station antenna to the multipath prevention fence in the φ direction.
【００３８】Ｄφは基地局アンテナから水平面φ方向の
壁までの水平距離、Ｈは天井の高さ、Ｈｒは床から端末
局アンテナまでの高さ、Ｈｔは基地局アンテナと天井の
距離、θｄφは基地局アンテナから水平φ方向の屋内最
遠点へ届く直接波の放射角のθｄφである。Dφ is the horizontal distance from the base station antenna to the wall in the horizontal φ direction, H is the height of the ceiling, Hr is the height from the floor to the terminal station antenna, Ht is the distance between the base station antenna and the ceiling, θdφ is The radiation angle θdφ of the direct wave reaching the indoor farthest point in the horizontal φ direction from the base station antenna.
【００３９】反射・吸収面となるフェンスの距離Ｒφの
値は９０度に近い入射角を得るために、基地局アンテナ
からφ方向によらず一定の値とする。フェンスの天井か
らの垂直下方高Ｈφは式（１３）で求められる。 Ｈφ＝Ｈｔ＋Ｒφtan（θｄφ）−λＲφ（１−Ｒφ／Ｄφ）……（１３）The value of the distance Rφ of the fence serving as the reflection / absorption surface is constant regardless of the φ direction from the base station antenna in order to obtain an incident angle close to 90 degrees. The vertical lower height Hφ from the ceiling of the fence is obtained by Expression (13). Hφ = Ht + Rφtan (θdφ) −λRφ (1-Rφ / Dφ) (13)
【００４０】図６は本発明の実施の形態の第２の例を示
す図であって、（ａ）は外観図、（ｂ）は放射方向の垂
直断面図である。この例は、円筒形の電波遮蔽体を基地
局アンテナからφ方向に応じたＨφで変化させた高さで
カットした形となる。同図において、数字符号４は天
井、１２は送信点、１３は電波を遮蔽する材質のフェン
ス、１７は基地局アンテナから直接、端末局アンテナに
到来する波の伝搬経路を表わしている。FIGS. 6A and 6B show a second example of the embodiment of the present invention. FIG. 6A is an external view, and FIG. 6B is a vertical sectional view in the radial direction. In this example, a cylindrical radio wave shield is cut from a base station antenna at a height changed by Hφ according to the φ direction. In the figure, numeral 4 indicates a ceiling, 12 indicates a transmission point, 13 indicates a fence made of a material for shielding radio waves, and 17 indicates a propagation path of a wave arriving directly from a base station antenna to a terminal station antenna.
【００４１】図７は、本発明の第１の配置例を示す図で
あって、三面図を示している。同図において、（ａ）は
上面図、（ｂ）は側面図、（ｃ）は正面図を示してい
る。同図において、数字符号１は床、４は天井、１２は
送信点、１３は電波を遮蔽する材質のフェンス、１６は
端末局アンテナの高さを示す線を表わしている。FIG. 7 is a view showing a first arrangement example of the present invention, and is a three-view drawing. In the figure, (a) shows a top view, (b) shows a side view, and (c) shows a front view. In the figure, numeral 1 denotes a floor, 4 denotes a ceiling, 12 denotes a transmission point, 13 denotes a fence made of a material for shielding radio waves, and 16 denotes a line indicating the height of the terminal station antenna.
【００４２】図８は本発明の実施の形態の第３の例を示
す図であって、（ａ）は外観図、（ｂ）は放射方向の垂
直断面図である。請求項４の天井設置の例で部屋と相似
形にすることにより、フェンスの高さが均一になる。同
図において、数字符号４は天井、１１は電波遮蔽体、１
２は送信点、１３は電波を遮蔽する材質のフェンスを表
わしている。FIGS. 8A and 8B are views showing a third example of the embodiment of the present invention, wherein FIG. 8A is an external view, and FIG. 8B is a vertical sectional view in the radial direction. By making the shape similar to the room in the example of the ceiling installation of claim 4, the height of the fence becomes uniform. In the figure, numeral 4 is a ceiling, 11 is a radio wave shield, 1
Reference numeral 2 denotes a transmission point, and reference numeral 13 denotes a fence made of a material for shielding radio waves.
【００４３】図９は、本発明の第２の配置例を示す図で
あって、図８に示すフェンスを天井に設置した場合の三
面図を示しており、（ａ）は上面図、（ｂ）は側面図、
（ｃ）は正面図を示している。同図において、数字符号
１は床、４は天井、１２は送信点、１３は電波を遮蔽す
る材質のフェンス、１６は端末局アンテナの高さを示す
線を表わしている。FIGS. 9A and 9B are views showing a second arrangement example of the present invention, showing three views when the fence shown in FIG. 8 is installed on the ceiling, wherein FIG. 9A is a top view, and FIG. ) Is a side view,
(C) shows a front view. In the figure, numeral 1 denotes a floor, 4 denotes a ceiling, 12 denotes a transmission point, 13 denotes a fence made of a material for shielding radio waves, and 16 denotes a line indicating the height of the terminal station antenna.
【００４４】図１０は、本発明のその他の配置例を示す
図であって、本発明のフェンスを側壁付近に設置した場
合の上面図と、コーナーに設置した場合の上面図を示し
ている。同図において、数字符号１２は送信点、１３は
電波を遮蔽する材質のフェンスを表わしている。FIG. 10 is a view showing another arrangement example of the present invention, and shows a top view when the fence of the present invention is installed near a side wall and a top view when it is installed at a corner. In the figure, numeral 12 indicates a transmission point, and 13 indicates a fence made of a material for shielding radio waves.
【００４５】図１１は、本発明の実施の形態の第４の例
を示す図であって、本発明のフェンスを天井に設置した
場合の三面図を示している。同図において、数字符号１
は床、４は天井、１２は送信点、１３は電波を遮蔽する
材質のフェンス、１４は天井に配置した電波吸収体パネ
ル、１６は端末局アンテナの高さを示す線を表わしてい
る。FIG. 11 is a view showing a fourth example of the embodiment of the present invention, and is a three-view drawing when the fence of the present invention is installed on a ceiling. In FIG.
Denotes a floor, 4 denotes a ceiling, 12 denotes a transmission point, 13 denotes a fence made of a material for shielding radio waves, 14 denotes a radio wave absorber panel arranged on the ceiling, and 16 denotes a line indicating the height of the terminal station antenna.
【００４６】図１２は、本発明の実施の形態の第５の例
を示す図であって、本発明のフェンスを側壁に設置した
場合の三面図を示している。同図において、数字符号１
は床、４は天井、１２は送信点、１３は電波を遮蔽する
材質のフェンス、１５は壁に配置した電波吸収体のパネ
ル、１６は端末局アンテナの高さを示す線を表わしてい
る。FIG. 12 is a view showing a fifth example of the embodiment of the present invention, and is a three-view drawing in which the fence of the present invention is installed on a side wall. In FIG.
Denotes a floor, 4 denotes a ceiling, 12 denotes a transmission point, 13 denotes a fence made of a material for shielding radio waves, 15 denotes a panel of a radio wave absorber disposed on a wall, and 16 denotes a line indicating the height of a terminal station antenna.
【００４７】図１３は、本発明の実施の形態の第６の例
を示す図であって、本発明のフェンスをコーナーに設置
した場合の三面図を示している。同図において、数字符
号１は床、４は天井、１２は送信点、１３は電波を遮蔽
する材質のフェンス、１４は天井に配置した電波吸収体
のパネル、１５は壁に配置した電波吸収体のパネル、１
６は端末局アンテナの高さを示す線を表わしている。FIG. 13 is a view showing a sixth example of the embodiment of the present invention, and is a three-view drawing in which the fence of the present invention is installed at a corner. In the figure, numeral 1 is a floor, 4 is a ceiling, 12 is a transmission point, 13 is a fence made of a material for shielding radio waves, 14 is a panel of a radio wave absorber arranged on the ceiling, and 15 is a radio wave absorber arranged on a wall Panel, 1
Reference numeral 6 denotes a line indicating the height of the terminal station antenna.
【００４８】[0048]
【発明の効果】以上、説明したように、本発明のマルチ
パス防止フェンスは、無線ＬＡＮ等の屋内高速無線通信
装置を実現する上で問題となるマルチパスフェージング
を、無線基地局アンテナを包囲して設置したフェンスに
よって、その原因となる放射角で伝搬する電波を伝搬経
路上で遮断することにより抑圧する。As described above, the multipath prevention fence of the present invention covers multipath fading, which is a problem in realizing an indoor high-speed wireless communication device such as a wireless LAN, around a radio base station antenna. The fence installed in the vertical direction suppresses the radio wave propagating at the radiation angle that causes it by blocking it on the propagation path.
【００４９】基地局アンテナにマルチパスフェージング
を低減させるためのヌル点成形等の複雑なビーム成形機
能を持つアンテナを使用すること無く、対向する壁や天
井からの２回以上反射波を抑圧し、長遅延反射波による
マルチパスフェージングを低減させることにより、誤り
率（ＢＥＲ）、Ｄ／Ｕ（希望波と干渉波の比）を大きく
改善した高品質な屋内高速無線通信を、非常に簡易なア
ンテナ構成の無線通信装置で実現することができる。Without using an antenna having a complicated beam shaping function such as null point shaping for reducing multipath fading in the base station antenna, the reflected wave from the opposing wall or ceiling can be suppressed twice or more, A high-quality indoor high-speed wireless communication with greatly improved error rate (BER) and D / U (ratio of desired wave to interference wave) by reducing multipath fading due to long-delay reflected waves, using a very simple antenna The present invention can be realized by a wireless communication device having a configuration.
【図１】本発明の実施の形態の第１の例を示す図であ
る。FIG. 1 is a diagram showing a first example of an embodiment of the present invention.
【図２】電波の遮蔽すべき角度の定式化を説明する図で
ある。FIG. 2 is a diagram illustrating the formulation of an angle at which radio waves should be shielded.
【図３】遮蔽に使用するフェンスの高さの定式化を説明
する図である。FIG. 3 is a diagram illustrating the formulation of the height of a fence used for shielding.
【図４】従来の屋内無線通信装置と短遅延の干渉波の伝
搬経路を示す図である。FIG. 4 is a diagram showing a conventional indoor wireless communication apparatus and a propagation path of a short-delay interference wave.
【図５】従来の屋内無線通信装置と長遅延の干渉波の伝
搬経路を示す図である。FIG. 5 is a diagram showing a conventional indoor wireless communication apparatus and a propagation path of a long-delay interference wave.
【図６】本発明の実施の形態の第２の例を示す図であ
る。FIG. 6 is a diagram showing a second example of the embodiment of the present invention.
【図７】本発明の第１の配置例を示す図である。FIG. 7 is a diagram showing a first arrangement example of the present invention.
【図８】本発明の実施の形態の第３の例を示す図であ
る。FIG. 8 is a diagram showing a third example of the embodiment of the present invention.
【図９】本発明の第２の配置例を示す図である。FIG. 9 is a diagram showing a second arrangement example of the present invention.
【図１０】本発明のその他の配置例を示す図である。FIG. 10 is a diagram showing another arrangement example of the present invention.
【図１１】本発明の実施の形態の第４の例を示す図であ
る。FIG. 11 is a diagram showing a fourth example of an embodiment of the present invention.
【図１２】本発明の実施の形態の第５の例を示す図であ
る。FIG. 12 is a diagram showing a fifth example of an embodiment of the present invention.
【図１３】本発明の実施の形態の第６の例を示す図であ
る。FIG. 13 is a diagram showing a sixth example of the embodiment of the present invention.
１ 床 ２ 基地局アンテナ背後の壁 ３ 端末局アンテナ背後の壁 ４ 天井 ５ 基地局装置 ６ 端末局装置 ７ 基地局アンテナ ８ 端末局アンテナ ９ 基地局アンテナの垂直面内の放射パターン １０ 端末局アンテナの垂直面内の放射パターン １１ 電波遮蔽体 １２ 送信点（送信アンテナの位置） １３ 電波を遮蔽する材質のフェンス １４ 天井に配置した電波吸収体のパネル １５ 壁に配置した電波吸収体のパネル １６ 端末局アンテナの高さを示す線 １７〜１９，２３，２４ 電波の伝搬経路 ２０〜２２ 電波の伝搬経路に置かれたフェンスによ
る遮蔽Reference Signs List 1 floor 2 wall behind base station antenna 3 wall behind terminal station antenna 4 ceiling 5 base station device 6 terminal station device 7 base station antenna 8 terminal station antenna 9 radiation pattern in vertical plane of base station antenna 10 terminal station antenna Radiation pattern in vertical plane 11 Radio wave shield 12 Transmission point (position of transmitting antenna) 13 Fence made of material that blocks radio waves 14 Panel of radio wave absorber placed on ceiling 15 Panel of radio wave absorber placed on wall 16 Terminal station Line indicating height of antenna 17-19, 23, 24 Radio wave propagation path 20-22 Screen shielding by fence placed in radio wave propagation path
Claims (5)
つの端末局の間で通信を行う屋内無線通信装置におい
て、 部屋の天井の高さをＨ、床から端末局アンテナまでの高
さをＨｒ、基地局アンテナと天井の距離をＨｔ、基地局
アンテナから水平面においてＸ軸に対する角度がφの方
向の壁までの距離をＤφとするとき、水平面から下方に
“数１”で示す式（１）で与えられるθｄφの範囲の電
波を、無線基地局アンテナを包囲する、電波遮蔽体等の
電波を吸収するか、又は、反射して透過させない材質で
構成したフェンスで遮ると共に、 【数１】 基地局アンテナからφ方向のフェンスまでの距離をＲφ
とするとき、フェンスの天井からの垂直下方高が、ほ
ぼ、式（２）を満足することを特徴とするマルチパス防
止フェンス。 Ｈφ＝Ｈｔ＋Ｒφtan（θｄφ）−λＲφ（１−Ｒφ／Ｄφ）………（２）At least one base station and at least one
In an indoor wireless communication device that performs communication between two terminal stations, the height of the ceiling of the room is H, the height from the floor to the terminal station antenna is Hr, the distance between the base station antenna and the ceiling is Ht, and the distance from the base station antenna is Ht. Assuming that the distance from the wall in the direction in which the angle with respect to the X axis is φ in the horizontal plane is Dφ, a radio wave in the range of θdφ given by Expression (1) shown by “Equation 1” below the horizontal plane is transmitted to the radio base station antenna. Surround with a fence made of a material that absorbs or reflects and does not transmit radio waves such as a radio wave shield or the like. The distance from the base station antenna to the fence in the φ direction is Rφ
Wherein the vertical lower height from the ceiling of the fence substantially satisfies Expression (2). Hφ = Ht + Rφtan (θdφ) −λRφ (1-Rφ / Dφ) (2)
にし基地局アンテナを中心とする水平面の円周上にフェ
ンスを配置し、基地局アンテナからの方向φに依らず、
電波のフェンスへ水平面の入射角が９０度となることを
特徴とする請求項１記載のマルチパス防止フェンス。2. A fence is arranged on the circumference of a horizontal plane centered on the base station antenna with Rφ being constant regardless of the angle φ from the X axis, regardless of the direction φ from the base station antenna.
2. The multipath prevention fence according to claim 1, wherein an incident angle of a horizontal plane to the radio wave fence is 90 degrees.
る方向φに依らずフェンスの高さＨφが一定となる部屋
の水平断面形状の極座標（φ，Ｄφ）と式（３）の関係
を持つ部屋の水平断面と相似形の水平面フェンス配列
（φ，Ｒφ′）で、フェンスの方向φの厚みＴが（Ｒ
φ′−Ｒφ）であることを特徴とする請求項１または請
求項２記載のマルチパス防止フェンス。 Ｄφ＝ｎ×Ｒφ′（但し、ｎは１以上の任意の定数） ………………（３）3. The relationship between the polar coordinates (φ, Dφ) of the horizontal sectional shape of the room where the height Hφ of the fence is constant irrespective of the direction φ given as a special solution of the expression (2), and the expression (3) In a horizontal plane fence arrangement (φ, Rφ ′) similar to the horizontal cross section of a room having
The multipath prevention fence according to claim 1 or 2, wherein (φ'-Rφ). Dφ = n × Rφ ′ (where n is an arbitrary constant of 1 or more) (3)
ェンスに囲まれた範囲の内側の天井に電波を吸収する材
質の板状パネルを配置した請求項１〜請求項３記載マル
チパス防止フェンス。4. The multipath prevention fence according to claim 1, wherein a plate-like panel made of a material absorbing radio waves is disposed on a ceiling inside a range surrounded by the multipath prevention fence surrounding the base station antenna.
ェンスに囲まれる範囲の側壁に電波を吸収する材質の板
状パネルを配置した請求項１〜請求項４記載マルチパス
防止フェンス。5. The multipath prevention fence according to claim 1, wherein a plate-like panel made of a material absorbing radio waves is disposed on a side wall in a range surrounded by the multipath prevention fence surrounding the base station antenna.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP04311697A JP3456512B2 (en) | 1997-02-27 | 1997-02-27 | Multipath prevention fence and multipath prevention equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP04311697A JP3456512B2 (en) | 1997-02-27 | 1997-02-27 | Multipath prevention fence and multipath prevention equipment |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH10242748A true JPH10242748A (en) | 1998-09-11 |
| JP3456512B2 JP3456512B2 (en) | 2003-10-14 |
Family
ID=12654876
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP04311697A Expired - Fee Related JP3456512B2 (en) | 1997-02-27 | 1997-02-27 | Multipath prevention fence and multipath prevention equipment |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3456512B2 (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000234403A (en) * | 1999-02-17 | 2000-08-29 | Shimizu Corp | Electromagnetic wave shield building prepared for radio lan |
| JP2000269734A (en) * | 1999-03-19 | 2000-09-29 | Kankyo Denji Gijutsu Kenkyusho:Kk | Installation space for radio communication |
| JP2001345631A (en) * | 2000-06-01 | 2001-12-14 | Mitsubishi Electric Corp | Converter method in electric wave environment, reflection structure body, and on-road communication system |
| JP2002064327A (en) * | 2000-08-18 | 2002-02-28 | Toshiba Corp | Multipath fading preventing device for radio communication equipment |
| JP2008131582A (en) * | 2006-11-24 | 2008-06-05 | Toyota Motor Corp | Antenna apparatus |
| JP2009204344A (en) * | 2008-02-26 | 2009-09-10 | Fujitsu Ltd | Radio system |
| DE102021106857A1 (en) | 2021-03-19 | 2022-09-22 | Deutsches Zentrum für Luft- und Raumfahrt e.V. | System for reducing interference caused by multipath propagation |
-
1997
- 1997-02-27 JP JP04311697A patent/JP3456512B2/en not_active Expired - Fee Related
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000234403A (en) * | 1999-02-17 | 2000-08-29 | Shimizu Corp | Electromagnetic wave shield building prepared for radio lan |
| JP2000269734A (en) * | 1999-03-19 | 2000-09-29 | Kankyo Denji Gijutsu Kenkyusho:Kk | Installation space for radio communication |
| JP2001345631A (en) * | 2000-06-01 | 2001-12-14 | Mitsubishi Electric Corp | Converter method in electric wave environment, reflection structure body, and on-road communication system |
| JP2002064327A (en) * | 2000-08-18 | 2002-02-28 | Toshiba Corp | Multipath fading preventing device for radio communication equipment |
| JP2008131582A (en) * | 2006-11-24 | 2008-06-05 | Toyota Motor Corp | Antenna apparatus |
| JP4600387B2 (en) * | 2006-11-24 | 2010-12-15 | トヨタ自動車株式会社 | Antenna device |
| JP2009204344A (en) * | 2008-02-26 | 2009-09-10 | Fujitsu Ltd | Radio system |
| DE102021106857A1 (en) | 2021-03-19 | 2022-09-22 | Deutsches Zentrum für Luft- und Raumfahrt e.V. | System for reducing interference caused by multipath propagation |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3456512B2 (en) | 2003-10-14 |
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