JP2008244677A

JP2008244677A - Method for calculating boundary point where direction to move in leakage transmission line changes and leakage coaxial cable for which direction to move is displayed by the method

Info

Publication number: JP2008244677A
Application number: JP2007080405A
Authority: JP
Inventors: Satoru Akashi; 悟明石; Hisahiro Matsushita; 尚弘松下; Tomonori Sugiyama; 智則杉山; Jun Yaginuma; 順柳沼
Original assignee: Tokyo Electric Power Co Inc
Current assignee: Tokyo Electric Power Company Holdings Inc
Priority date: 2007-03-27
Filing date: 2007-03-27
Publication date: 2008-10-09

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for calculating a boundary point where a direction to move in a leakage transmission line changes and a leakage coaxial cable for which the direction to move is displayed by the method. <P>SOLUTION: In a communication system configured by grading-connecting two or more leakage transmission lines of different coupling loss, connecting a wireless base station to the end part of the leakage transmission line of the largest coupling loss and connecting a terminator to the end part of the leakage transmission line of the smallest coupling loss, when the length of a first leakage transmission line 11 in the preceding stage of the two or more leakage transmission lines is defined as L, the transmission loss per unit length of the first leakage transmission line 11 is defined as α and the difference of the coupling loss of the first and second leakage transmission lines 11 and 12 is defined as β, and the distance y<SB>0</SB>from the end part on the feed side of the boundary point where the direction to move changes in the first leakage transmission line 11 is calculated by an equation y<SB>0</SB>=L-β/(2×α). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

本発明は、無線基地局に接続され、この無線基地局のアンテナとして機能する漏洩伝送路において移動すべき方向が変化する境界点を算出する方法、及び、この方法により移動すべき方向が表示された漏洩同軸ケーブルに関する。 The present invention is a method for calculating a boundary point at which a direction to move in a leaky transmission line connected to a radio base station and functioning as an antenna of the radio base station, and a direction to move by this method are displayed. Related to leaky coaxial cable.

トンネルのような長手方向において有効な通信を行う方式として、この長手方向に沿って延設された漏洩伝送路（漏洩同軸ケーブル）をアンテナとして用いてデータ通信を行う通信システムがある。例えば、図１４に示すように、複数の漏洩同軸ケーブル（この例では２本の漏洩同軸ケーブル１７１，１７２）の各々の両端に接続端子１６１，１６２，１６３，１６４を取り付け、これらを接続用ケーブル（同軸ケーブル）１５３で直列に接続し、さらに、一方の端部に接続用ケーブル１５１を介して無線基地局１１１を接続し、他方の端部に接続用ケーブル１５２を介して終端器１１０が接続されて構成されている。この漏洩同軸ケーブル１７１，１７２の延設位置にある移動通信端末（例えば、携帯電話１４１や無線通信機能を備えたコンピュータ１４２）は、いずれかの漏洩同軸ケーブル１７１，１７２と無線結合され、これらの移動通信端末１４１，１４２間、あるいは、移動通信端末１４１，１４２と無線基地局１１１間でのデータの送受信が行われる（例えば、特許文献１参照）。
特開平５−８３２５８号公報 As a method of performing effective communication in the longitudinal direction such as a tunnel, there is a communication system that performs data communication using a leaky transmission line (leaky coaxial cable) extending along the longitudinal direction as an antenna. For example, as shown in FIG. 14, connection terminals 161, 162, 163, and 164 are attached to both ends of each of a plurality of leaky coaxial cables (in this example, two leaky coaxial cables 171 and 172), and these are connected to the connection cables. (Coaxial cable) 153 is connected in series, and the radio base station 111 is connected to one end via a connection cable 151, and the terminator 110 is connected to the other end via a connection cable 152. Has been configured. A mobile communication terminal (for example, a mobile phone 141 or a computer 142 having a wireless communication function) at an extension position of the leaky coaxial cables 171 and 172 is wirelessly coupled to any one of the leaky coaxial cables 171 and 172. Data transmission / reception is performed between the mobile communication terminals 141 and 142 or between the mobile communication terminals 141 and 142 and the radio base station 111 (see, for example, Patent Document 1).
JP-A-5-83258

通常、漏洩伝送路から漏れる電波（電界）は、無線基地局に近いほど強く、終端方向に向かうにつれて弱くなる。そのため、漏洩伝送路の終端側にある移動通信端末は通信が瞬断したり、場合によっては途絶することがある。この時、この移動通信端末を、漏洩伝送路に沿って電波環境の良い方向、すなわち、無線基地局が接続されている方向に移動させることで安定した通信を行うことができるが、漏洩伝送路が長距離にわたって敷設されていたり、複雑に入り組んだトンネル内に敷設されている場合には、無線基地局が接続されている方向を確認することができず、この漏洩伝送路に沿った２方向の内のどちらが電波環境の良い方向であるかを判別することができないという課題があった。 Usually, the radio wave (electric field) leaking from the leaky transmission path is stronger as it gets closer to the radio base station, and becomes weaker toward the terminal end. For this reason, the mobile communication terminal on the terminal side of the leaky transmission path may be interrupted or may be interrupted in some cases. At this time, stable communication can be performed by moving the mobile communication terminal along the leaky transmission path in a direction having a good radio wave environment, that is, a direction in which the radio base station is connected. Is installed over a long distance or in a complicated tunnel, the direction to which the radio base station is connected cannot be confirmed, and the two directions along this leaky transmission line There was a problem that it was not possible to determine which of the directions was better in the radio wave environment.

本発明はこのような課題に鑑みてなされたものであり、漏洩伝送路における移動すべき方向が変化する境界点を算出する方法、及び、この方法により移動すべき方向が表示された漏洩同軸ケーブルを提供することを目的とする。 The present invention has been made in view of such a problem, and a method for calculating a boundary point where the direction of movement in a leaky transmission path changes, and a leaky coaxial cable displaying the direction of movement by this method The purpose is to provide.

前記課題を解決するために、本発明に係る方法は、結合損失が異なる２以上の漏洩伝送路が当該結合損失が大きい順に接続され、当該結合損失が最も大きい漏洩伝送路の端部に無線基地局を接続し、当該結合損失が最も小さい漏洩伝送路の端部に終端器を接続して構成した通信システムにおいて、２以上の漏洩伝送路のうち前段にある漏洩伝送路（例えば、実施形態における第１の漏洩伝送路１１）における移動すべき方向が変化する境界点を算出する方法であって、前段の漏洩伝送路の長さをＬとし、前段の漏洩伝送路の単位長さ当たりの伝送損失をαとし、前段の漏洩伝送路とこの前段の漏洩伝送路に接続された後段の漏洩伝送路（例えば、実施形態における第２の漏洩伝送路１２）との結合損失の差をβとしたとき、境界点の前段の漏洩伝送路の給電側の端部からの距離ｙ₀を次式
ｙ₀ ＝Ｌ−β／（２×α）
により算出する。 In order to solve the above-described problem, the method according to the present invention is configured such that two or more leaky transmission lines having different coupling losses are connected in order of increasing coupling loss, and a radio base is connected to an end of the leaky transmission line having the largest coupling loss. In a communication system configured by connecting stations and connecting a terminator to the end of the leaky transmission line having the smallest coupling loss, the leaky transmission line in the preceding stage of two or more leaky transmission lines (for example, in the embodiment) A method of calculating a boundary point where the direction of movement in the first leaky transmission line 11) changes, wherein the length of the previous leaky transmission line is L and transmission per unit length of the previous leaky transmission line The loss is α, and the difference in coupling loss between the preceding leakage transmission path and the subsequent leakage transmission path connected to the preceding leakage transmission path (for example, the second leakage transmission path 12 in the embodiment) is β. Leakage before the boundary point The distance y ₀ from the end of the transmission line on the power feeding side is expressed as follows: y ₀ = L−β / (2 × α)
Calculated by

このような本発明に係る漏洩伝送路における移動すべき方向が変化する境界点を算出する方法において、漏洩伝送路が、結合損失が異なる２以上の漏洩同軸ケーブルから構成されることが好ましい。あるいは、漏洩伝送路が、結合損失が異なる２以上の区間を有する１本の漏洩同軸ケーブルの当該区間により構成されることが好ましい。 In such a method of calculating the boundary point where the direction to be moved in the leaky transmission line according to the present invention changes, it is preferable that the leaky transmission line is composed of two or more leaky coaxial cables having different coupling losses. Or it is preferable that a leaky transmission line is comprised by the said area | region of the one leaky coaxial cable which has two or more areas from which a coupling loss differs.

また、本発明に係る漏洩同軸ケーブルは、導電性材料からなる中心導体と、当該中心導体の周りを覆う絶縁性材料からなる円筒状の絶縁体と、当該絶縁体の周りを覆い、複数のスロットが形成された導電性材料からなる外部導体と、当該外部導体の周りを覆う絶縁性材料からなる外被とから構成され、この外被の表面に、上述の漏洩伝送路における移動すべき方向が変化する境界点を算出する方法のいずれかにより求められる境界点を境に、端部の方向を指す記号が長手方向に沿って表示される。 The leaky coaxial cable according to the present invention includes a central conductor made of a conductive material, a cylindrical insulator made of an insulating material covering the center conductor, and a plurality of slots covering the periphery of the insulator. Is formed of an outer conductor made of a conductive material and an outer jacket made of an insulating material covering the outer conductor, and the direction of movement in the above-described leakage transmission path is on the surface of the outer jacket. A symbol indicating the direction of the end portion is displayed along the longitudinal direction at the boundary point obtained by any of the methods for calculating the changing boundary point.

このような本発明に係る漏洩同軸ケーブルにおいて、記号が、外皮の長手方向沿って螺旋状に並んで表示されていることが好ましい。あるいは記号が、外皮の長手方向に沿って複数列表示されていることが好ましい。 In such a leaky coaxial cable according to the present invention, it is preferable that the symbols are displayed in a spiral form along the longitudinal direction of the outer skin. Alternatively, the symbols are preferably displayed in a plurality of rows along the longitudinal direction of the outer skin.

本発明に係る漏洩伝送路における移動すべき方向が変化する境界点を算出する方法を以上のように構成すると、結合損失が異なる複数の漏洩伝送路が接続されていたとしても、前段の漏洩伝送路の長さ及び単位長さ当たりの伝送損失と、この前段の漏洩伝送路の結合損失及び後段の漏洩伝送路の結合損失の差とから境界点の位置を算出することができるので、簡単な計算で正確に求めることができる。 If the method for calculating the boundary point at which the direction to move in the leaky transmission line according to the present invention changes is configured as described above, even if a plurality of leaky transmission lines with different coupling losses are connected, the leaky transmission in the previous stage is connected. Since the position of the boundary point can be calculated from the difference between the transmission loss per path length and unit length, the coupling loss of the preceding leakage transmission line, and the coupling loss of the subsequent leakage transmission path, It can be calculated accurately by calculation.

また、この方法により境界点を算出して漏洩同軸ケーブルの外被に移動すべき方向を示す記号を表示することにより、電波状況によって移動通信端末の無線基地局との通信が不安定な場合には、この漏洩伝送路に表示された記号により、この移動通信端末を漏洩伝送路に沿って、漏洩伝送路（漏洩同軸ケーブル）から発射される電波の電界強度の移動平均値が高くなる方向が判別可能となり、この方向に移動させることにより安定した通信を行うことができる。 In addition, when the boundary point is calculated by this method and the symbol indicating the direction to move is displayed on the jacket of the leaky coaxial cable, the communication with the radio base station of the mobile communication terminal is unstable due to the radio wave condition. Indicates a direction in which the moving average value of the electric field strength of the radio wave emitted from the leaky transmission line (leakage coaxial cable) is increased along the leaky transmission line by the symbol displayed on the leaky transmission line. It becomes possible to discriminate, and stable communication can be performed by moving in this direction.

以下、本発明の好ましい実施形態について図面を参照して説明する。まず、図１を用いて本実施例に係る漏洩伝送路を構成する漏洩同軸ケーブルの構造について説明する。漏洩同軸ケーブル５０は、導電性材料からなる中心導体５１と、この中心導体５１の周りを覆う絶縁性材料からなる円筒状の絶縁体５２と、この絶縁体５２の周りを覆う導電性材料からなる外部導体５３と、この外部導体５３の周りを覆う絶縁性材料からなる外被５４とから構成される。この外部導体５３には、漏洩同軸ケーブル５０が延びる方向に沿って多数の小さな穴（これを「スロット５５」と呼ぶ）が形成されており、隣接するスロット５５が相互に作用して送受信アンテナとして機能する。 Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. First, the structure of a leaky coaxial cable constituting the leaky transmission line according to the present embodiment will be described with reference to FIG. The leaky coaxial cable 50 is composed of a central conductor 51 made of a conductive material, a cylindrical insulator 52 made of an insulating material covering the center conductor 51, and a conductive material covering the periphery of the insulator 52. The outer conductor 53 and the outer cover 54 made of an insulating material covering the outer conductor 53 are formed. The outer conductor 53 has a number of small holes (referred to as “slots 55”) along the direction in which the leaky coaxial cable 50 extends, and the adjacent slots 55 interact with each other to serve as a transmission / reception antenna. Function.

それでは、このような漏洩同軸ケーブル５０が用いられた漏洩伝送路における電界強度の分布について説明する。図２は、１本の漏洩同軸ケーブルを用いて通信システムを構成した場合を示しており、漏洩伝送路１の両端には接続端子２，３が接続され、それぞれの接続端子２，３を介して無線基地局４と終端器５とが接続されている。この漏洩伝送路１から漏れる電波の強度（電界強度）は、図３に示すように、無線基地局４に近いほど強く、漏洩伝送路１の長手方向に沿って徐々に弱くなり、終端器５付近が最も弱くなる。 The electric field strength distribution in the leaky transmission line using such a leaky coaxial cable 50 will now be described. FIG. 2 shows a case where a communication system is configured using a single leaky coaxial cable. Connection terminals 2 and 3 are connected to both ends of the leaky transmission line 1, and the connection terminals 2 and 3 are connected to each other. The radio base station 4 and the terminator 5 are connected. As shown in FIG. 3, the strength of the radio wave leaking from the leaky transmission path 1 (electric field strength) becomes stronger as it is closer to the radio base station 4 and gradually decreases along the longitudinal direction of the leaky transmission path 1. The neighborhood is the weakest.

本実施例に係る漏洩伝送路１を構成する漏洩同軸ケーブルの表面（図１における外被５４の表面）には、上述の電界強度が上昇する方向、すなわち、無線基地局４が接続されている方向が記号６（図２の場合は「＜」）によって示されている。図４に示すように、終端器５付近に位置する移動通信端末７が無線基地局４と通信を行う際、その付近の電波環境によっては無線基地局４からの電波が弱く、通信が不安定になることもある。その場合には、漏洩伝送路１の表面に印されている無線基地局４が接続された側の接続端子２の方向、つまり無線基地局４がある方向を示す記号６を確認し、この漏洩伝送路１に沿って移動通信端末７を無線基地局４がある方向に移動させることにより、電波環境が改善され、無線基地局４と安定して通信ができるようになる。 The direction in which the electric field strength increases, that is, the radio base station 4 is connected to the surface of the leaky coaxial cable constituting the leaky transmission line 1 according to the present embodiment (the surface of the jacket 54 in FIG. 1). The direction is indicated by the symbol 6 (“<” in the case of FIG. 2). As shown in FIG. 4, when the mobile communication terminal 7 located near the terminator 5 communicates with the radio base station 4, the radio wave from the radio base station 4 is weak depending on the radio wave environment in the vicinity, and the communication is unstable. Sometimes it becomes. In that case, the direction of the connection terminal 2 on the side to which the radio base station 4 connected to the surface of the leaky transmission line 1 is connected, that is, the symbol 6 indicating the direction in which the radio base station 4 is located is confirmed. By moving the mobile communication terminal 7 along the transmission path 1 in a certain direction, the radio wave environment is improved and stable communication with the radio base station 4 can be achieved.

なお、図２等では無線基地局４を接続した側の接続端子２の方向、つまり無線基地局４がある方向を示す記号６として「＜」が用いられているが、この記号に限らず図５に示す記号６′のように矢印等、無線基地局４のある方向の判断が可能であればどんな表示でも良い。また、以上の説明においては、無線基地局４が接続端子２を介して、直接、漏洩伝送路１に接続されている場合について説明したが、無線基地局４と漏洩伝送路１の接続端子２との間には給電線や分配器などが挿入されることもある。 In FIG. 2 and the like, “<” is used as a symbol 6 indicating the direction of the connection terminal 2 on the side to which the radio base station 4 is connected, that is, the direction in which the radio base station 4 is located. As long as the direction of the radio base station 4 can be determined, such as an arrow as indicated by a symbol 6 'shown in FIG. In the above description, the case where the radio base station 4 is directly connected to the leaky transmission path 1 via the connection terminal 2 has been described. However, the connection terminal 2 between the radio base station 4 and the leaky transmission path 1 is described. A feeder line or a distributor may be inserted between the two.

次に、図６に示すように、結合損失が大きい第１の漏洩伝送路１１と、この第１の漏洩伝送路１１より結合損失が小さい第２の漏洩伝送路１２とを直列に接続した構成（グレーディング接続）における電界強度の分布について説明する。この通信システムにおいて、第１の漏洩伝送路１１及び第２の漏洩伝送路１２の各々の端部には接続端子２１，２２及び接続端子３１，３２が接続されており、さらに、接続端子２２，３１を繋ぐように接続用ケーブル１３が接続され、第１及び第２の漏洩伝送路１１，１２は直列に接続されている。そして、第１の漏洩伝送路１１の接続端子２１に無線基地局４が接続され、第２の漏洩伝送路１２の接続端子３２に終端器５が接続されて通信システムが構成されている。 Next, as shown in FIG. 6, a configuration in which a first leaky transmission line 11 having a large coupling loss and a second leaky transmission line 12 having a coupling loss smaller than that of the first leaky transmission line 11 are connected in series. The distribution of electric field strength in (grading connection) will be described. In this communication system, connection terminals 21 and 22 and connection terminals 31 and 32 are connected to end portions of the first leaky transmission line 11 and the second leaky transmission line 12, respectively. The connection cable 13 is connected so as to connect 31, and the first and second leaky transmission lines 11 and 12 are connected in series. The wireless base station 4 is connected to the connection terminal 21 of the first leaky transmission line 11, and the terminator 5 is connected to the connection terminal 32 of the second leaky transmission line 12 to constitute a communication system.

このようなグレーディング接続時における第１及び第２の漏洩伝送路１１，１２から漏れる電界強度の分布を図７に示す。この図７に示すように、第１の漏洩伝送路１１から漏れる電波（電界）は、無線基地局４に接続された端部（以下、「第１の入力端１１ａ」と呼ぶ）が最も強く、この第１の漏洩伝送路１１の長手方向に沿って徐々に弱くなり、第２の漏洩伝送路１２側の接続端子２２に接続された端部（以下、「第１の終端１１ｂ」と呼ぶ）付近が最も弱くなる。そして、第２の漏洩伝送路１２の第１の漏洩伝送路１１との接続点（以下、「第２の入力端１２ａ」と呼ぶ）付近で、結合損失の差分だけ受信レベルが高くなり、その後、第２の漏洩伝送路１２の長手方向に沿って終端器５に近づくにつれて徐々に弱くなる。なお、第１及び第２の漏洩伝送路１１，１２から漏れる電波の強度（電界強度）は、上述のスロット５５の大きさ等により決定される。 FIG. 7 shows the distribution of the electric field strength leaking from the first and second leaky transmission lines 11 and 12 at the time of such grading connection. As shown in FIG. 7, the radio wave (electric field) leaking from the first leaky transmission line 11 is strongest at the end connected to the radio base station 4 (hereinafter referred to as “first input end 11a”). The first leaky transmission line 11 is gradually weakened along the longitudinal direction and connected to the connection terminal 22 on the second leaky transmission line 12 side (hereinafter referred to as “first terminal 11b”). ) The neighborhood is the weakest. In the vicinity of the connection point of the second leaky transmission line 12 with the first leaky transmission line 11 (hereinafter referred to as “second input end 12a”), the reception level increases by the difference in coupling loss, and thereafter , It gradually weakens as it approaches the terminator 5 along the longitudinal direction of the second leaky transmission line 12. Note that the strength (electric field strength) of radio waves leaking from the first and second leaky transmission lines 11 and 12 is determined by the size of the slot 55 and the like.

上述のように、第２の漏洩伝送路１２の結合損失を第１の漏洩伝送路１１の結合損失よりも大きくすることにより、第２の漏洩伝送路１２における第２の入力端１２ａでの電界強度が、第１の漏洩伝送路１１の第１の終端１１ｂの近傍における電界強度よりも大きくなるため、第１の漏洩伝送路１１の第１の終端１１ｂの付近にある移動通信端末は、受信状態を良くするために、第１の漏洩伝送路１１の第１の入力端１１ａ側に移動する方が近い場合と、第１の終端１１ｂ側（第２の入力端１２ａ側）に移動する方が近い場合とがある。そこで、第１の漏洩伝送路１１のどちらの端部側へ移動する方が近いかを判断するための境界点の算出方法を以下に説明する。 As described above, the electric field at the second input end 12a in the second leaky transmission line 12 is made by making the coupling loss of the second leaky transmission line 12 larger than the coupling loss of the first leaky transmission line 11. Since the strength is greater than the electric field strength in the vicinity of the first end 11b of the first leaky transmission path 11, the mobile communication terminal in the vicinity of the first end 11b of the first leaky transmission path 11 In order to improve the condition, it is closer to the first input end 11a side of the first leaky transmission line 11 and to the first end 11b side (second input end 12a side) May be close. Therefore, a boundary point calculation method for determining which end side of the first leaky transmission path 11 is closer will be described below.

まず、図８に示すように、無線基地局４の送信電力をＰ_tとし、第１の漏洩伝送路１１の長さをＬとし、第１の漏洩伝送路１１の結合損失をβ₁とし、第２の漏洩伝送路１２の結合損失をβ₂とし（但し、β₁＞β₂）、第１の漏洩伝送路１１の単位長さ当たりの伝送損失をαとすると、第１の漏洩伝送路１１における第１の入力端１１ａから距離ｘ₀（但し、ｘ₀＜Ｌ）離れた位置の受信電界強度Ｐ_{r1_x0}は次式（１）で表され、第２の漏洩伝送路１２の第２の入力端１２ａの受信電界強度Ｐ_{r2_0}は次式（２）で表される。なお、図８は、電界強度の分布の特徴を明確にするために近似値で表している。 First, as shown in FIG. 8, the transmission power of the radio base station 4 and P _t, the length of the first leaky transmission line 11 is L, the coupling loss of the first leaky transmission line 11 and beta _1, If the coupling loss of the second leaky transmission line 12 is β ₂ (where β ₁ > β ₂ ) and the transmission loss per unit length of the first leaky transmission line 11 is α, the first leaky transmission line 11, the received electric field strength P _{r1 — x0 at} a position away from the first input end 11 a by a distance x ₀ (where x ₀ <L) is expressed by the following equation (1), and the second leakage transmission path 12 second The received electric field strength P _{r2 — 0} at the input terminal 12a is expressed by the following equation (2). FIG. 8 shows approximate values in order to clarify the characteristics of the electric field intensity distribution.

Ｐ_{r1_x0} ＝Ｐ_t−（αｘ₀＋β₁）（１）
Ｐ_{r2_0} ＝Ｐ_t−（αＬ＋β₂）（２） P _r1 — _x0 = P _t − (αx ₀ + β ₁ ) (1)
P _r2 — ₀ = P _t − (αL + β ₂ ) (2)

この式（１），（２）より、第１の漏洩伝送路１１の受信電界強度Ｐ_{r1_x0}が、第２の漏洩伝送路１２の第２の入力端１２ｂの受信電界強度Ｐ_{r2_0}と同じ大きさになる距離ｘ₀を求めると、次式（３）で表される。なお、この式（３）において、第１の漏洩伝送路１１の結合損失β₁と第２の漏洩同軸ケーブル１２の結合損失β₂との差をβ（β＝β₁−β₂）と定義している。 The equation (1), (2) from the reception field strength P _{R1_x0} is the same size as the received field strength P _{R2_0} the second input end 12b of the second leaky transmission line 12 of the first leaky transmission line 11 When the distance x ₀ is obtained, it is expressed by the following equation (3). Incidentally, in this equation (3), the coupling loss of the first leaky transmission line 11 beta ₁ and the difference between the coupling loss beta ₂ of the second leaky coaxial cable 12 beta and (beta = beta _1-beta ₂₎ Definition is doing.

ｘ₀＝Ｌ−β／α （３） x ₀ = L−β / α (3)

この式（３）から明かな通り、第１の漏洩伝送路１１の第１の入力端１１ａからＬ−β／αだけ離れた位置ｘ₀の電界強度は、第２の漏洩伝送路１２の第２の入力端１２ａの電界強度とほぼ同じである。そのため、第１の漏洩伝送路１１の位置ｘ₀と第１の終端１１ｂとの間にある移動通信端末は、これらの中間地点Ｙを境に第１の入力端１１ａに近い場合はこの第１の入力端１１ａの方向に移動し、第１の終端１１ｂに近い場合は第１の終端１１ｂの方に移動した方が安定した通信が可能となる。ここで、第１の入力端１１ａから境界点Ｙまでの距離ｙ₀は、次式（４）で表される。 As is clear from this equation (3), the electric field strength at the position x ₀ that is separated from the first input end 11 a of the first leaky transmission line 11 by L−β / α is the second leaky transmission line 12. 2 is almost the same as the electric field strength of the input terminal 12a. Therefore, when the mobile communication terminal located between the position x ₀ of the first leaky transmission line 11 and the first terminal end 11b is close to the first input terminal 11a with these intermediate points Y as a boundary, If the input terminal 11a moves toward the first terminal 11b and is close to the first terminal 11b, stable communication is possible by moving toward the first terminal 11b. Here, the distance y ₀ from the first input end 11a to the boundary point Y is expressed by the following equation (4).

ｙ₀ ＝Ｌ−β／（２×α）（４） y ₀ = L−β / (2 × α) (4)

以上より、第１の漏洩伝送路１１において、この第１の漏洩伝送路１１の給電点、すなわち、第１の入力端１１ａからL−β／(2×α)離れた位置までの区間の表面には無線基地局４のある方向を示す記号１６ａを、また、第１の漏洩伝送路１１の第１の入力端１１ａよりＬ−β／(2×α)離れた位置から第２の漏洩伝送路１２との接続点、すなわち、第１の終端１１ｂまでの区間の表面にはこの第１の終端１１ｂのある方向を示す記号１６ｂを記すことにより、電界強度が上昇する方向を表示することができる。 As described above, in the first leaky transmission line 11, the surface of the section from the feeding point of the first leaky transmission line 11, that is, the position away from the first input end 11a by L−β / (2 × α). Is a symbol 16a indicating a certain direction of the radio base station 4, and the second leaky transmission from a position L-β / (2 × α) away from the first input end 11a of the first leaky transmission line 11. A direction in which the electric field strength increases can be displayed by marking a symbol 16b indicating the direction of the first terminal end 11b on the surface of the connection point with the path 12, that is, the section to the first terminal end 11b. it can.

なお、図９に示すように、実際のグレーディング接続の際には、第１の漏洩伝送路１１に沿って変化する電界強度は、後段の第２の漏洩伝送路１２からの電波の輻射により、上述の境界点１１よりも第１の終端側１１ｂから徐々に上昇していく。そこで、第１の漏洩伝送路１１の第１の入力端１１ａから受信レベルが上昇を開始する地点までの区間の表面には無線基地局４のある方向を示す記号１６ａ′を、また、受信レベルが上昇を開始する地点Ｙ′から第２の漏洩伝送路１２との接続点（第１の終端１１ｂ）までの区間の表面には第１の終端１１ｂのある方向を示す記号１６ｂ′を記すことも可能である。 As shown in FIG. 9, in the actual grading connection, the electric field strength that changes along the first leaky transmission line 11 is due to the radiation of the radio wave from the second leaky transmission line 12 in the subsequent stage. It gradually rises from the first end side 11b above the boundary point 11 described above. Therefore, the symbol 16a ′ indicating the direction in which the radio base station 4 is present is displayed on the surface of the section from the first input end 11a of the first leaky transmission line 11 to the point where the reception level starts to rise, and the reception level A symbol 16b ′ indicating the direction in which the first end 11b is located is marked on the surface of the section from the point Y ′ at which the start of the rise starts to the connection point (first end 11b) with the second leaky transmission line 12. Is also possible.

図１０に示すように結合損失の大きい第１の漏洩伝送路１１の第２の漏洩伝送路１２との接続点（第１の終端１１ｂ）付近に位置する移動通信端末７が無線基地局４と通信を行う際、その付近の電波環境によっては無線基地局４からの電波が弱く、通信が不安定になることもある。その場合には、第１の漏洩伝送路１１の第１の終端１１ｂ付近の区間の表面に印されている第２の漏洩伝送路１２との接続点のある方向を示す記号１６ｂ′を確認し、第２の漏洩伝送路１２との接続点付近、あるいは第２の漏洩伝送路１２側まで移動通信端末７を移動させることにより、電波環境が改善され、無線基地局４と安定して通信ができるようになる。 As shown in FIG. 10, the mobile communication terminal 7 located near the connection point (first termination 11 b) of the first leaky transmission line 11 with a large coupling loss to the second leaky transmission line 12 is connected to the radio base station 4. When performing communication, depending on the surrounding radio wave environment, the radio wave from the radio base station 4 may be weak and the communication may become unstable. In that case, confirm the symbol 16b 'indicating the direction of the connection point with the second leaky transmission path 12 marked on the surface of the section near the first end 11b of the first leaky transmission path 11. By moving the mobile communication terminal 7 to the vicinity of the connection point with the second leaky transmission path 12 or to the second leaky transmission path 12 side, the radio wave environment is improved, and stable communication with the radio base station 4 is achieved. become able to.

ここで、図１１に示すように、グレーディング接続の構成は、結合損失が大きい第１の区間４１と、結合損失がこの第１の区間４１よりも小さい第２の区間４２とを、接続部材を用いずに一連で形成した漏洩同軸ケーブル４０を用いて漏洩伝送路を構成することも可能である。この場合にも、この漏洩同軸ケーブル４０の第１の区間４１の長さＬ、単位長さ当たりの伝送損失α、及び、接続損失β₁と、第２の区間４２の接続損失β₂とから、上述の式（１）〜（４）を用いて境界点を求め、電界強度が上昇する方向を示す記号２６を漏洩ケーブル４０の表面に表示することができる。 Here, as shown in FIG. 11, the grading connection configuration includes a first section 41 having a large coupling loss and a second section 42 having a coupling loss smaller than the first section 41 by connecting members. It is also possible to configure a leaky transmission line using a leaky coaxial cable 40 formed in series without using it. In this case, the length L of the first section 41 of the leakage coaxial cable 40, the transmission loss per unit length alpha, and a connection loss beta _1, the connection loss beta ₂ Metropolitan of the second section 42 The boundary points can be obtained using the above-described formulas (1) to (4), and the symbol 26 indicating the direction in which the electric field strength increases can be displayed on the surface of the leakage cable 40.

以上説明したように、接続された２本の漏洩伝送路のうち、前段の（無線基地局４に近い方の）漏洩伝送路（第１の漏洩伝送路１１）における電界強度の上昇方向の境界点Ｙは、この第１の漏洩伝送路１１の長さＬ及び単位長さ当たりの伝送損失αと、この前段の漏洩伝送路と接続された後段の（第１の漏洩伝送路１１の無線基地局４と反対側の端部に接続された）漏洩伝送路（第２の漏洩伝送路１２）との結合損失の差βから算出することができる。そのため、特性の異なる漏洩伝送路を直列に接続させたグレーディング構成は、本実施例に示すような２種類の漏洩伝送路で構成するだけに限らず、３種類以上の漏洩伝送路が直列接続されている場合も同様の方法で算出できるため、前段の漏洩伝送路の接続点付近の区間の表面に、後段の漏洩伝送路との接続点のある方向が目視により判別可能な記号を表示することができる。 As described above, of the two leaky transmission lines connected, the boundary in the increasing direction of the electric field strength in the leaky transmission line (first leaky transmission line 11) at the preceding stage (closer to the radio base station 4) The point Y indicates the length L of the first leaky transmission line 11 and the transmission loss α per unit length, and the subsequent stage (the radio base of the first leaky transmission line 11 connected to the leaky transmission line of the first stage. It can be calculated from the difference β in coupling loss with the leaky transmission line (second leaky transmission line 12) connected to the end opposite to the station 4. Therefore, the grading configuration in which leaky transmission lines having different characteristics are connected in series is not limited to the two kinds of leaky transmission lines as shown in the present embodiment, and three or more kinds of leaky transmission lines are connected in series. Since the same method can be used, the direction of the connection point with the subsequent leaky transmission line should be displayed visually on the surface of the section near the connection point of the previous leaky transmission line. Can do.

図１２は、漏洩伝送路１の表面に備えられた無線基地局４と直接或いは給電系を介して接続する側の端部方向を示す別の手段である。この漏洩伝送路１を敷設する場合、支持線付きの漏洩伝送路であれば問題がないが、敷設環境によっては支持線がない漏洩伝送路を敷設することがある。その場合、敷設方法によっては漏洩伝送路が捩れてしまうことがある。この時、図２に示したように漏洩伝送路１の表面に表示された無線基地局４を接続する側の接続端子２の方向を示す記号６が、漏洩伝送路１の長手方向に１列のみに表示されている場合、移動通信端末がある位置から記号６を確認することができない場合もある。そこで、この図１２に示すように、無線基地局４を接続する側の接続端子２の方向を示す表示３６を漏洩伝送路１の表面に、長手方向に対して螺旋状に表示する。これにより、漏洩伝送路１が捩れて敷設された場合でも、無線基地局４がある方向を確認することができる。 FIG. 12 shows another means for indicating the direction of the end portion on the side connected to the radio base station 4 provided on the surface of the leaky transmission line 1 directly or via a power feeding system. When this leaky transmission line 1 is laid, there is no problem if it is a leaky transmission line with a support line, but depending on the laying environment, a leaky transmission line without a support line may be laid. In that case, depending on the laying method, the leakage transmission path may be twisted. At this time, as shown in FIG. 2, the symbol 6 indicating the direction of the connection terminal 2 on the connection side of the radio base station 4 displayed on the surface of the leaky transmission line 1 is arranged in a line in the longitudinal direction of the leaky transmission line 1. In the case where the symbol 6 is displayed only, the symbol 6 may not be confirmed from a position where the mobile communication terminal is located. Therefore, as shown in FIG. 12, a display 36 indicating the direction of the connection terminal 2 on the side to which the radio base station 4 is connected is displayed on the surface of the leaky transmission line 1 in a spiral shape with respect to the longitudinal direction. Thereby, even when the leaky transmission line 1 is twisted and laid, the direction in which the radio base station 4 is present can be confirmed.

図１３は、漏洩伝送路１の表面に備えられた無線基地局と直接或いは給電系を介して接続する側の端部方向を示す別の手段である。漏洩伝送路１の製造設備上、図１２に示したように無線基地局４を接続する側の接続端子２の方向を示す表示３６を螺旋状に印すことが出来ない場合もある。その場合には、この図１３に示すように、無線基地局４を接続する側の接続端子２の方向を示す表示４６を漏洩伝送路１の表面に、円周上に複数列表示する。これにより、漏洩伝送路１が捩れて敷設された場合でも、無線基地局４がある方向を確認することができる。 FIG. 13 shows another means for indicating the direction of the end portion on the side that is connected to the radio base station provided on the surface of the leaky transmission line 1 directly or via a feeding system. Due to the manufacturing facility of the leaky transmission line 1, there may be a case where the display 36 indicating the direction of the connection terminal 2 on the side to which the wireless base station 4 is connected cannot be spirally marked as shown in FIG. In this case, as shown in FIG. 13, a display 46 indicating the direction of the connection terminal 2 on the side to which the radio base station 4 is connected is displayed on the surface of the leaky transmission line 1 in a plurality of rows on the circumference. Thereby, even when the leaky transmission line 1 is twisted and laid, the direction in which the radio base station 4 is present can be confirmed.

漏洩同軸ケーブルの構成を示す説明図である。It is explanatory drawing which shows the structure of a leaky coaxial cable. １本の漏洩伝送路で構成した通信システムを示す説明図である。It is explanatory drawing which shows the communication system comprised by one leaky transmission line. １本の漏洩伝送路の電界強度の分布を示す説明図である。It is explanatory drawing which shows distribution of the electric field strength of one leaky transmission line. １本の漏洩伝送路における移動端末の受信状態を改善する方法を示す説明図である。It is explanatory drawing which shows the method of improving the reception state of the mobile terminal in one leaky transmission line. 漏洩伝送路に表示される記号の別の実施形態を示す説明図である。It is explanatory drawing which shows another embodiment of the symbol displayed on a leaky transmission line. ２本の漏洩伝送路をグレーディング接続した通信システムを示す説明図である。It is explanatory drawing which shows the communication system which graded-connected two leaked transmission lines. ２本の漏洩伝送路をグレーディング接続したときの電界強度の分布を示す説明図である。It is explanatory drawing which shows distribution of the electric field strength when two leaky transmission lines are graded-connected. 移動すべき方向の境界点を算出する方法を説明するための説明図である。It is explanatory drawing for demonstrating the method of calculating the boundary point of the direction which should move. 第２の漏洩伝送路からの輻射を考慮して境界点を決定する方法を説明するための説明図である。It is explanatory drawing for demonstrating the method to determine a boundary point in consideration of the radiation from a 2nd leaky transmission line. ２本の漏洩伝送路における移動端末の受信状態を改善する方法を示す説明図である。It is explanatory drawing which shows the method of improving the reception state of the mobile terminal in two leaky transmission lines. １本の漏洩伝送路でグレーディング接続を実現した場合を示す説明図である。It is explanatory drawing which shows the case where grading connection is implement | achieved by one leaky transmission line. 漏洩伝送路に表示される記号の別の実施形態を示す説明図である。It is explanatory drawing which shows another embodiment of the symbol displayed on a leaky transmission line. 漏洩伝送路に表示される記号の別の実施形態を示す説明図である。It is explanatory drawing which shows another embodiment of the symbol displayed on a leaky transmission line. 漏洩伝送路を用いた通信システムの構成を示す説明図である。It is explanatory drawing which shows the structure of the communication system using a leaky transmission line.

符号の説明Explanation of symbols

１１第１の漏洩伝送路（前段の漏洩伝送路）
１２第２の漏洩伝送路（後段の漏洩伝送路）
５０漏洩同軸ケーブル
５１中心導体
５２絶縁体
５３外部導体
５４外被
５５スロット 11 First leaky transmission line (previous stage leaky transmission line)
12 Second leaky transmission line (leakage transmission line at the latter stage)
50 Leaky coaxial cable 51 Center conductor 52 Insulator 53 Outer conductor 54 Outer jacket 55 Slot

Claims

結合損失が異なる２以上の漏洩伝送路が当該結合損失が大きい順に接続され、当該結合損失が最も大きい漏洩伝送路の端部に無線基地局を接続し、当該結合損失が最も小さい漏洩伝送路の端部に終端器を接続して構成した通信システムにおいて、前記２以上の漏洩伝送路のうち前段にある漏洩伝送路における移動すべき方向が変化する境界点を算出する方法であって、
前記前段の漏洩伝送路の長さをＬとし、前記前段の漏洩伝送路の単位長さ当たりの伝送損失をαとし、前記前段の漏洩伝送路と当該前段の漏洩伝送路に接続された後段の漏洩伝送路との結合損失の差をβとしたとき、前記境界点の前記前段の漏洩伝送路の給電側の端部からの距離ｙ₀を次式
ｙ₀ ＝Ｌ−β／（２×α）
により算出する、漏洩伝送路における移動すべき方向が変化する境界点を算出する方法。 Two or more leaky transmission lines with different coupling losses are connected in order of increasing coupling loss, a radio base station is connected to the end of the leaky transmission line with the largest coupling loss, and the leakage transmission line with the smallest coupling loss is connected. In a communication system configured by connecting a terminator to an end, a method of calculating a boundary point where a direction to move in a leaky transmission line in the previous stage among the two or more leaky transmission lines changes,
The length of the preceding leakage transmission path is L, the transmission loss per unit length of the preceding leakage transmission path is α, and the downstream leakage transmission path connected to the preceding leakage transmission path and the preceding leakage transmission path When the difference in coupling loss with the leaky transmission path is β, the distance y ₀ from the end of the previous stage leaky transmission path to the feeding side of the boundary point is expressed by the following equation y ₀ = L−β / (2 × α )
The method of calculating the boundary point where the direction to be moved in the leaky transmission path is calculated by

前記漏洩伝送路が、前記結合損失が異なる２以上の漏洩同軸ケーブルから構成される請求項１に記載の漏洩伝送路における移動すべき方向が変化する境界点を算出する方法。 The method for calculating a boundary point at which a direction to be moved in the leaky transmission line changes in the leaky transmission line according to claim 1, wherein the leaky transmission line is composed of two or more leaky coaxial cables having different coupling losses.

前記漏洩伝送路が、前記結合損失が異なる２以上の区間を有する１本の漏洩同軸ケーブルの当該区間により構成される請求項１に記載の漏洩伝送路における移動すべき方向が変化する境界点を算出する方法。 The boundary point at which the direction to be moved in the leaky transmission path changes according to claim 1, wherein the leaky transmission path is configured by the section of one leaky coaxial cable having two or more sections having different coupling losses. How to calculate.

導電性材料からなる中心導体と、当該中心導体の周りを覆う絶縁性材料からなる円筒状の絶縁体と、当該絶縁体の周りを覆い、複数のスロットが形成された導電性材料からなる外部導体と、当該外部導体の周りを覆う絶縁性材料からなる外被とから構成される漏洩同軸ケーブルであって、
前記外被の表面に、請求項１〜３のいずれか一項に記載の漏洩伝送路における移動すべき方向が変化する境界点を算出する方法により求められる前記境界点を境に、端部の方向を指す記号が長手方向に沿って表示された漏洩同軸ケーブル。 A central conductor made of a conductive material, a cylindrical insulator made of an insulating material covering the periphery of the central conductor, and an outer conductor made of a conductive material covering the periphery of the insulator and formed with a plurality of slots And a leaky coaxial cable composed of a jacket made of an insulating material covering the periphery of the outer conductor,
The surface of the jacket is bordered on the boundary point obtained by the method of calculating the boundary point at which the direction of movement in the leaky transmission path according to any one of claims 1 to 3 changes. Leaky coaxial cable with direction symbols displayed along the length.

前記記号が、前記外皮の長手方向沿って螺旋状に並んで表示されている請求項４に記載の漏洩同軸ケーブル。 The leaky coaxial cable according to claim 4, wherein the symbols are displayed in a spiral form along the longitudinal direction of the outer skin.

前記記号が、前記外皮の長手方向に沿って複数列表示されている請求項４に記載の漏洩同軸ケーブル。 The leaky coaxial cable according to claim 4, wherein the symbols are displayed in a plurality of rows along the longitudinal direction of the outer skin.