JPH0222988A - Catv trunk network - Google Patents
Catv trunk networkInfo
- Publication number
- JPH0222988A JPH0222988A JP17197888A JP17197888A JPH0222988A JP H0222988 A JPH0222988 A JP H0222988A JP 17197888 A JP17197888 A JP 17197888A JP 17197888 A JP17197888 A JP 17197888A JP H0222988 A JPH0222988 A JP H0222988A
- Authority
- JP
- Japan
- Prior art keywords
- catv
- signal
- amplifier
- trunk network
- output
- 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.)
- Pending
Links
- 230000008054 signal transmission Effects 0.000 claims abstract description 27
- 238000009434 installation Methods 0.000 claims 1
- 230000005540 biological transmission Effects 0.000 abstract description 24
- 238000010586 diagram Methods 0.000 description 6
Abstract
Description
［産業上の利用分野］
本発明は、接続構成に特徴を有するＣＡＴＶ幹線網に関
する。
［従来の技術］
まずＣＡＴＶ幹線網の一般的な構成例を第４図に従って
概略説明する。
ヘッドエンド装置１１はＣＡＴＶ信号等を送出する部分
であり、双方向ＣＡＴＶシステムに於ては受信端末側か
ら送られてきた信号の最終到達点も兼ねる。このヘッド
エンド装置１１から送出された信号は幹線増幅器１２分
配増幅器１３によって、伝送損失による信号レベル低下
分の補正や複数の信号伝送方向への信号の分配が行われ
、最終的には分岐増幅器１４又は１５の分岐端子から受
信端末１６、又は１７へ分配が行われる。このような−
膜内なＣＡＴＶ幹線網においては、ヘッドエンド装置゛
から一つの受信端末へ信号が伝送される経路は通常−通
りだけである。
第５図は第４図と同様の一般的なＣＡＴＶ幹線網の主要
幹線部分のみを抽出し簡略化した図である。この図にお
いてもヘッドエンド装置２１から幹線網の末端部、例え
ば分岐増幅器２６や２９の分岐出力へ信号が伝送される
経路は−通りだけである。
［発明が解決しようとする課題］
上述の説明のように従来の一般的なＣＡＴＶ幹線網にお
いては−通りのみであった、ヘッドエンド装置から受信
端末へ到る信号伝送経路に、新たな信号伝送経路を付加
して複数の伝送経路によって信号伝送を行う事を可能に
し、
（１）ＣＡＴＶ幹線網内の一部で事故が発生した際に、
事故箇所をＣＡＴＶ幹線から切離し、事故箇所を迂回す
る他の信号伝送経路で信号伝送を行う事によって事故の
影響がＣＡＴＶ幹線網内の他の部分に波及する事を防ぐ
。
（２） 特定の経路にのみ信号伝送を行う事を可能と
する。
という機能を実現する事を目的とする。[Industrial Field of Application] The present invention relates to a CATV trunk network that is characterized by its connection configuration. [Prior Art] First, a general configuration example of a CATV trunk network will be briefly described with reference to FIG. The headend device 11 is a part that sends out CATV signals and the like, and also serves as the final destination of signals sent from the receiving terminal side in a two-way CATV system. The signal sent from the headend device 11 is sent to the main amplifier 12 by the distribution amplifier 13, which compensates for the drop in signal level due to transmission loss, and distributes the signal to multiple signal transmission directions.Finally, the signal is sent to the branch amplifier 14. Alternatively, distribution is performed from the 15 branch terminals to the receiving terminal 16 or 17. Like this-
In an intra-film CATV trunk network, there are usually only one route for transmitting a signal from a headend device to a single receiving terminal. FIG. 5 is a diagram similar to FIG. 4 in which only the main trunk portions of a general CATV trunk network are extracted and simplified. In this figure as well, there are only - paths through which signals are transmitted from the headend device 21 to the terminal end of the trunk network, for example, the branch outputs of the branch amplifiers 26 and 29. [Problem to be solved by the invention] As explained above, in the conventional general CATV trunk network, there was only one path, but a new signal transmission path from the head end device to the receiving terminal is required. By adding routes, it is possible to transmit signals using multiple transmission routes, and (1) when an accident occurs in a part of the CATV trunk network,
By separating the accident location from the CATV trunk line and transmitting signals via another signal transmission route that bypasses the accident location, the effects of the accident are prevented from spreading to other parts of the CATV trunk network. (2) Enables signal transmission only to a specific route. The purpose is to realize this function.
【課題を解決するための手段及び作用】本発明は、複数
の信号伝送経路の中から所望の信号伝送経路を選択的に
指定するために、入出力切換器をＣＡＴＶ用増幅器に内
蔵し、ＣＡＴＶ幹線網内の一部に設置した信号伝送経路
制御装置から送出される制御信号によって入出力切換器
を制御しＣＡＴＶ信号の伝送される方向を変えるように
したものである。
［実施例］
以下図面を参照して本発明の一実施例を説明する。
第１図はその回路構成を示すもので、ヘッドエンド装置
３１、ＣＡＴＶ用増幅器３２〜３９、伝送線路４０〜４
７から構成される部品は上記第５図に示した一般的なＣ
ＡＴＶ幹線網の例と基本的には等しい。
ソシテ、ＣＡＴＶＪ１４幅器３２．３４，３６゜３９に
入出力切換器を内蔵したものを使用し、伝送線路４７．
４８が付加される。ＣＡＴＶ用増幅器に内蔵された入出
力切換器は信号伝送経路制御装置４９からの制御信号に
よって制御する事が可能である。
まず初めに、ＣＡＴＶ用増幅器３４〜３６、伝送線路４
３，４４．４８によって構成される部分について説明を
行う。これはＣＡＴＶ幹線網内で発生した事故部分を回
避する為の構成である。伝送線路４１を通ってＣＡＴＶ
用増幅器４４に送られてきたＣＡＴＶ信号は、通常は伝
送線路４３に出力され、ＣＡＴＶ用増幅器３５、伝送線
路４４、ＣＡＴＶ用増幅器３６の順に伝送される。ここ
でＣＡＴＶ用増幅器３５が故障し、出力断となった場合
について考える。正常時にはＣＡＴＶ用増幅器３４の出
力信号は図中ｄの出力端子にのみ出力されており、ＣＡ
ＴＶ用増幅器３６の入力端子はｃ、ｄ共に入力可能であ
る。この時、ＣＡＴＶ用増幅器３５の故障が検知された
ならばａからの信号の出力を停止し、６から出力するよ
うに伝送線路制御装置４９から制御信号を送出すれば、
故障の影響を受けるのはＣＡＴＶ用増幅器３５のみに信
号の供給を依存している受信端末だけで済む事になる。
次ｊ、ｍ ＣＡ Ｔ Ｖ用増幅器３２．３３．３７〜３
９、伝送線路４０，４１．４５〜４７．５０によって構
成される部分について説明を行なう。これはＣＡＴＶ幹
線網内に他の部分から独立した専用幹線を作る為の構成
である。
伝送線路４０を通ってＣＡＴＶ用増幅器３２１；送られ
てきたＣＡＴＶ信号は、通常は伝送線路４１を通ってＣ
ＡＴＶ用増幅器３３へ送られ、そこで分配された後に出
力信号の一方は伝送線路４２へ、他方４５を経てＣＡＴ
ｖ用増幅器３７へ送られる。続いて伝送線路４６、ＣＡ
ＴＶ用、増幅器３８、伝送線路４７、ＣＡＴｖ用増幅器
３９の順に伝送される。ここでヘッドエンド装置３１と
ＣＡＴＶ用増幅器３９の分岐出力に接続された受信端末
の間でのみＣＡＴＶ信号の授受を行い、他の幹線へはＣ
ＡＴＶ信号を漏らしてはならない、という状況になった
場合について考える。正常時にはＣＡＴＶ用増幅器３２
の出力信号は図中ノの出力端子にのみ出力されており、
ＣＡＴＶ用増幅器３９の入力端子ｇ、ｈは共に入力可能
である。
ここでヘッドエンド装置３１とＣＡＴＶ用増幅器３９の
間に専用幹線を構成するためには、ＣＡＴＶ用増幅器３
２の出力端子ｅからのＣＡＴＶ信号の出力を停止し、出
力端子ｆからのみ信号出力を行う。又ＣＡＴＶ用増幅器
３９の入力端子についてはｇからの入力を禁止し、入力
端子りのみ入力可能とし、出力端子ｉからの信号の出力
を停止するように信号伝送経路制御装置４９から制御信
号を送出すれば良い。これによってヘッドエンド装置３
１、ＣＡＴＶ用増幅器３２，３９１：対して専用のＣＡ
ＴＶ幹線が形成され、周囲のＣＡＴＶ幹線網から完全に
切り離す事ができる。さらにＣＡＴＶ用増幅器の分岐出
力を特定の受信端末とのみ信号授受可能にすれば、ヘッ
ドエンド装置と受信端末との間に専用幹線を構成するこ
とができる。
上述の構成可変型ＣＡＴＶ幹線網の基本的な構成例を発
展させる事によって様々な構成を築く事ができる。以下
にそのような一例を説明する。
第２図は環状に構成されたＣＡＴＶ幹線網の例である。
同図に於て、ヘッドエンド装置５１、ＣＡＴＶ用増幅器
５２〜５８、伝送線路６０〜６６から構成される部分は
上記第５図に示した一般的なＣＡＴＶ幹線網の例に基本
的にはほぼ等しい一般的なＣＡＴＶ幹線網であり、通常
はこの構成で動作している。
ここでＣＡＴＶ用増幅器５７の出力が断になる事故が発
生した場合について考える。この場合にはＣＡＴＶ用増
幅器５６の出力信号を、伝送線路７１を通してＣＡＴＶ
用増幅器５８に入力することで、ＣＡＴＶ用増幅器５７
の故障による他への影響を最少限に抑えることができる
。すなわち、通常の状態では、ａ＋ ｃ−Ｊ＋ ノ、
ｐ−ｔの各入出力端子が信号の入力又は出力が可能なよ
うに設定されているが、ＣＡＴＶ用増幅器５７の出力が
断となった場合には、ａ 、 ｃ 、 ｅ−Ｊ Ｉ
Ｉ ＋ ’ ＊ｔの各出力端子で信号の出力が可能
で、他の入出力端子による、信号の入出力が禁止となる
ように信号伝送経路制御装置５９から制御信号を送出す
れば良い。
次にＣＡＴＶ用増幅器５３の出力が断となった場合につ
いて考える。この場合、ＣＡＴＶ用増幅器５２の出力信
号を伝送線路６Ｂを通じてＣＡＴＶ用増幅器５７に入力
し、以下ＣＡＴＶ用増幅器５８．５６，５５．５４の順
に信号伝送を行う事により、ＣＡＴＶ用増幅器５３の故
障による他への影響を回避できる。すなわち、通常の状
態では先に述べた通りの入力端子又は出力端子の設定に
なっており、ＣＡＴＶ用増幅器５３が故障した場合には
す、ｇｘｓ、ｕ、ｍ、ｎ、ｈ、に、ｆの出力端子で信号
の入出力が可能で、他の入出力端子による信号の入出力
が禁止となるように信号伝送経路制御装置５９から制御
信号を送出すれば良い。
なお、ＣＡＴＶ用増幅器に内蔵の入出力切換器の代りに
ＣＡＴＶ用増幅器の外部に設置する形の信号伝送方向切
換器を用いて構成可変形ＣＡＴＶ幹線網を構成する事も
可能である。第３図にその様子を示す。
図中の８９〜９１が信号伝送方向切換器である。
信号伝送方向切換器８９を例にとると、伝送線路９２．
９３．９８を任意の組合せで電気的に接続・切断する事
により構成可変型ＣＡＴＶ幹線網を実現している。同図
において信号伝送方向切換器８９はＣＡＴＶ用増幅器８
７に接続されており、また、信号伝送方向切換器９０．
９１は相互に接続されている。
［発明の効果］
以上詳記した如く本発明によれば、入出力切換器をＣＡ
ＴＶ用増幅器に内蔵させ、ＣＡＴＶ幹線網内の一部に設
置した信号伝送経路制御装置から送出される制御信号に
よって複数の信号伝送経路の中から所望の信号伝送経路
を選択的に指定可能としたので、ＣＡＴＶ幹線網内での
事故発生時に事故箇所を迂回して信号を伝送させ、また
、特定の経路にのみ信号伝送を行うことが可能なＣＡＴ
Ｖ幹線網を提供することができる。Means and Effects for Solving the Problems The present invention incorporates an input/output switch in a CATV amplifier in order to selectively designate a desired signal transmission path from among a plurality of signal transmission paths. The input/output switch is controlled by a control signal sent from a signal transmission path control device installed in a part of the trunk network to change the direction in which CATV signals are transmitted. [Example] An example of the present invention will be described below with reference to the drawings. FIG. 1 shows the circuit configuration of the head end device 31, CATV amplifiers 32 to 39, transmission lines 40 to 4.
7 is the general C shown in Figure 5 above.
This is basically the same as the ATV trunk network example. Using the CATVJ14 width switch 32, 34, 36° 39 with a built-in input/output switch, the transmission line 47.
48 is added. The input/output switch built in the CATV amplifier can be controlled by a control signal from the signal transmission path control device 49. First of all, CATV amplifiers 34 to 36, transmission line 4
3, 44, and 48 will be explained. This is a configuration to avoid accidents occurring within the CATV trunk network. CATV through transmission line 41
The CATV signal sent to the CATV amplifier 44 is normally output to the transmission line 43 and transmitted to the CATV amplifier 35, the transmission line 44, and the CATV amplifier 36 in this order. Let us now consider a case where the CATV amplifier 35 fails and the output is cut off. During normal operation, the output signal of the CATV amplifier 34 is output only to the output terminal d in the figure,
Both c and d can be input to the input terminal of the TV amplifier 36. At this time, if a failure of the CATV amplifier 35 is detected, the output of the signal from a is stopped, and the control signal is sent from the transmission line control device 49 so as to be output from 6.
Only the receiving terminal that relies solely on the CATV amplifier 35 for signal supply will be affected by the failure. Next j, m CA TV amplifier 32.33.37~3
9. The portion constituted by the transmission lines 40, 41.45 to 47.50 will be explained. This is a configuration for creating a dedicated trunk line that is independent from other parts within the CATV trunk network. CATV amplifier 321 through transmission line 40; CATV signals sent through transmission line 41 are normally
After being sent to the ATV amplifier 33 and distributed there, one of the output signals is sent to the transmission line 42, and the other is sent to the CAT via the transmission line 45.
It is sent to the amplifier 37 for v. Next, transmission line 46, CA
The signal is transmitted to the TV amplifier 38, the transmission line 47, and the CATv amplifier 39 in this order. Here, CATV signals are exchanged only between the headend device 31 and the receiving terminal connected to the branch output of the CATV amplifier 39, and the CATV signals are not transmitted to other main lines.
Consider a situation where ATV signals must not be leaked. CATV amplifier 32 during normal operation
The output signal is output only to the output terminal shown in the figure.
Both input terminals g and h of the CATV amplifier 39 can be inputted. Here, in order to configure a dedicated trunk line between the headend device 31 and the CATV amplifier 39, the CATV amplifier 3
The output of the CATV signal from the output terminal e of No. 2 is stopped, and the signal is output only from the output terminal f. Furthermore, the signal transmission path control device 49 sends out a control signal to prohibit input from g to the input terminal of the CATV amplifier 39, allow input only to the input terminal, and stop outputting the signal from the output terminal i. Just do it. As a result, the head end device 3
1. CATV amplifier 32, 391: Dedicated CA for
A TV trunk line is formed and can be completely separated from the surrounding CATV trunk network. Furthermore, by making the branch output of the CATV amplifier capable of transmitting and receiving signals only with a specific receiving terminal, a dedicated trunk line can be constructed between the head-end device and the receiving terminal. Various configurations can be constructed by developing the basic configuration example of the configuration-variable CATV trunk network described above. One such example will be explained below. FIG. 2 is an example of a CATV trunk network configured in a ring. In the figure, the portion consisting of the headend device 51, CATV amplifiers 52 to 58, and transmission lines 60 to 66 is basically similar to the general CATV trunk network example shown in Figure 5 above. This is the same general CATV trunk network and normally operates with this configuration. Let us now consider the case where an accident occurs in which the output of the CATV amplifier 57 is cut off. In this case, the output signal of the CATV amplifier 56 is passed through the transmission line 71 to the CATV
By inputting it to the CATV amplifier 58, the CATV amplifier 57
The impact of a failure on others can be minimized. That is, under normal conditions, a+ c-J+ ノ,
Each input/output terminal of p-t is set to allow signal input or output, but if the output of CATV amplifier 57 is cut off, a, c, e-J I
It is only necessary to send a control signal from the signal transmission path control device 59 so that each output terminal of I + ' *t can output a signal, and input/output of signals through other input/output terminals is prohibited. Next, consider a case where the output of the CATV amplifier 53 is cut off. In this case, the output signal of the CATV amplifier 52 is input to the CATV amplifier 57 through the transmission line 6B, and the signal is transmitted to the CATV amplifiers 58, 56, 55, 54 in this order. You can avoid affecting others. In other words, under normal conditions, the input terminals or output terminals are set as described above, and if the CATV amplifier 53 fails, gxs, u, m, n, h, and f. It is only necessary to send a control signal from the signal transmission path control device 59 so that input/output of signals is possible at the output terminal and input/output of signals through other input/output terminals is prohibited. Note that it is also possible to construct a configuration-variable CATV trunk network using a signal transmission direction switch installed outside the CATV amplifier instead of the input/output switch built into the CATV amplifier. Figure 3 shows the situation. 89 to 91 in the figure are signal transmission direction switches. Taking the signal transmission direction switch 89 as an example, the transmission line 92.
By electrically connecting and disconnecting 93.98 in any combination, a configuration variable CATV trunk network is realized. In the figure, the signal transmission direction switch 89 is the CATV amplifier 8.
7, and is also connected to a signal transmission direction switch 90.
91 are interconnected. [Effects of the Invention] As detailed above, according to the present invention, the input/output switch can be
Built into the TV amplifier, it is possible to selectively specify a desired signal transmission path from among multiple signal transmission paths using control signals sent from a signal transmission path control device installed in a part of the CATV trunk network. Therefore, when an accident occurs within the CATV trunk network, CAT allows signals to be transmitted by bypassing the accident location, and also to transmit signals only along a specific route.
A V trunk network can be provided.
第１図ないし第３図は本発明の一実施例を示すもので、
第１図は基本的な回路構成を示すブロック図、第２図は
具体的構成例を示すブロック図、第３図は他の構成例を
示すブロック図、第４図は従来のＣＡＴＶ幹線網の回路
構成を示すブロック図、第５図は第４図の主要幹線部を
詳細に示すブロック図である。
１１．２１．３１．５１．８１・・・ヘッドエンド装置
、１２〜１５．２２〜２９．３２〜３９゜５２〜５８．
８２〜８８・ＣＡＴＶ用増幅器、１６．１７−ＣＡＴＶ
受信端末、４０〜４７゜６０〜７１．９３〜１００・Ｃ
ＡＴＶ用伝送経路、８９〜９１・・・信号伝送経路切換
器、ａ −ｕ・・・端子。1 to 3 show an embodiment of the present invention,
Fig. 1 is a block diagram showing the basic circuit configuration, Fig. 2 is a block diagram showing a specific configuration example, Fig. 3 is a block diagram showing another configuration example, and Fig. 4 is a block diagram showing a conventional CATV trunk network. FIG. 5 is a block diagram showing the main trunk section of FIG. 4 in detail. 11.21.31.51.81...Head end device, 12-15.22-29.32-39°52-58.
82-88・CATV amplifier, 16.17-CATV
Receiving terminal, 40~47°60~71.93~100・C
ATV transmission path, 89-91...Signal transmission path switch, a-u...Terminal.
Claims (1)
増幅器を順次接続し、ヘッドエンド装置から送出された
信号を最終的に受信端末に送り届けるＣＡＴＶ幹線網に
おいて、 任意のＣＡＴＶ増幅器の信号出力を他の任意のＣＡＴＶ
用増幅器の信号入力に接続する接続手段と、 ＣＡＴＶ幹線網の一部に設置され、信号入出力の方向を
制御してＣＡＴＶ施設設置完了後のＣＡＴＶ幹線網の構
成を可変する制御信号を出力する信号伝送経路制御手段
と を具備したことを特徴とするＣＡＴＶ幹線網。[Claims] In a CATV trunk network in which a headend device, a trunk amplifier, a distribution amplifier, and a branch amplifier are sequentially connected and a signal sent out from the headend device is finally sent to a receiving terminal, Signal output to any other CATV
a connection means that connects to the signal input of the CATV amplifier; and a connection means that is installed in a part of the CATV trunk network and outputs a control signal that controls the direction of signal input and output and changes the configuration of the CATV trunk network after the installation of the CATV facility is completed. A CATV trunk network characterized by comprising signal transmission path control means.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17197888A JPH0222988A (en) | 1988-07-12 | 1988-07-12 | Catv trunk network |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17197888A JPH0222988A (en) | 1988-07-12 | 1988-07-12 | Catv trunk network |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0222988A true JPH0222988A (en) | 1990-01-25 |
Family
ID=15933271
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP17197888A Pending JPH0222988A (en) | 1988-07-12 | 1988-07-12 | Catv trunk network |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0222988A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07162839A (en) * | 1993-12-07 | 1995-06-23 | Agency Of Ind Science & Technol | Catv system with fault restoration function |
| JPH07162838A (en) * | 1993-12-07 | 1995-06-23 | Agency Of Ind Science & Technol | Catv system with fault restoration function |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61191186A (en) * | 1985-02-19 | 1986-08-25 | Matsushita Electric Ind Co Ltd | Reliability enhancing device for catv repeating amplifier |
| JPH01114285A (en) * | 1987-10-28 | 1989-05-02 | Hitachi Cable Ltd | Automatic switching device for transmission trunk in catv system |
-
1988
- 1988-07-12 JP JP17197888A patent/JPH0222988A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61191186A (en) * | 1985-02-19 | 1986-08-25 | Matsushita Electric Ind Co Ltd | Reliability enhancing device for catv repeating amplifier |
| JPH01114285A (en) * | 1987-10-28 | 1989-05-02 | Hitachi Cable Ltd | Automatic switching device for transmission trunk in catv system |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07162839A (en) * | 1993-12-07 | 1995-06-23 | Agency Of Ind Science & Technol | Catv system with fault restoration function |
| JPH07162838A (en) * | 1993-12-07 | 1995-06-23 | Agency Of Ind Science & Technol | Catv system with fault restoration function |
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