JPH06204915A - Equalizer identifying device - Google Patents

Abstract

PURPOSE:To easily change the routes after construction of a system and also to easily replace an equalizer with another proper one in a maintenance state by providing an identifier circuit to identify the type and the equivalence value of the equalizer against another equalizer which is prepared at an amplifying part of the TV signals which are transmitted in a transmission system and compensates various characteristics of these signals. CONSTITUTION:An identifier circuit 18 is set in a case 17 and identifies the type, the equivalence value, etc., of an equalizer. When the circuit 18 is plugged in a relay amplifier 14, the circuit 18 is connected to a status monitor STM 20 via the terminals T4 and T5. The STM 20 serves as a remote monitor/control unit in the amplifier 14. That is, the circuit 18 consists of a power supply 18a of constant voltage connected in series to the STM 20, a fixed resistance 18b of the fixed resistance value, and a resistance 18c connected in parallel to the supply 18a and the resistance 18b. Then the circuit 18 is connected to the STM 20. The resistance value of the resistance 18c is varied in response to the type, the equivalence value, etc., of the equalizer 15 for identification of the equalizer 15. Thus it is possible to easily replace the equalizer 15 with another proper one after construction of a system.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an equalizer identifying device for identifying an equalizer installed in a relay amplifier used in a high frequency analog transmission system, for example, a CATV system.

[0002]

2. Description of the Related Art Conventionally, in a CATV system, as shown in FIG. 3, a center 1 having a supervisory control function in the system is used.
0 and each sub-center 11 to which a plurality of subscriber terminal devices 12 are connected are bidirectionally connected by a transmission line 13 such as a coaxial cable or an optical fiber cable, and the terminal devices of the subscribers connected to each sub-center 11 are connected. There are those that transmit necessary video signals and various electrical signals to the Twelve. Further, a plurality of relay amplifiers 14 are connected to the transmission line 13, and compensate each loss such as attenuation and distortion of each data signal on the transmission line 13 to transmit each data signal to the sub-center 11. It was

As shown in FIG. 4, the relay amplifier 14 includes an equalizer 15 such as an attenuator (ATT), an equalizer (EQ) or a pseudo line (BON) for equalizing the loss of a data signal due to the transmission line 13 and the like. It is composed of an amplifier 16. These equalizers 15 measure the input arrival level of each relay amplifier 14 after installing a transmission line, and select an appropriate type and equivalent amount from the measurement result,
It was connected to the transmission line 13 and the amplifier 16 by the plug-in method. In the above-mentioned relay amplifier, when it is necessary to change the equivalent amount of the equalizer due to a route change after the system is constructed, and when performing maintenance including transmission line troubles, the type of each equalizer And the equivalent amount was recognized, and the above equalizer was replaced with an appropriate one.

[0004]

However, in the above-mentioned relay amplifier, there is no means for recognizing the type of the equalizer in advance. Therefore, the lid of the relay amplifier is opened every time the replacement is performed, and the type of the equalizer is visually checked. I have to look it up. However, since the number of repeater amplifiers installed per facility is as large as several hundreds and the installation area extends to several Km, a great deal of labor is required to check the types of equalizers. was there.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an equalizer identifying apparatus that can easily recognize the type and equivalent amount of an equalizer.

[0006]

In order to achieve the above object, according to the present invention, an equalizer provided in an amplification section for amplifying a signal such as a television signal transmitted in a transmission system and compensating various characteristics of the signal. Corresponding to the above, there is provided an equalizer identification device including identification means for identifying the type and equivalent amount of the equalizer.

[0007]

The discriminating circuit which is a discriminating means for discriminating the type and equivalent amount of the equalizer is added to the relay amplifier which is the amplifying unit,
Enables recognition of equalizers on status monitors and centers.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings of FIGS. FIG. 1 is a block diagram showing an embodiment of an equalizer identifying apparatus according to the present invention. In the figure, the equalizer 15 is circuit-configured in a predetermined case 17 so that it can be plugged into the relay amplifier 14, and is connected to the transmission line 13 and the amplifier 16 by an input terminal T1 and an output terminal T2. Incidentally, T3 is a terminal for grounding.

Therefore, in the present embodiment, an identification circuit 18 for identifying the type and equivalent amount of the equalizer 15 is provided in the case 17 and is inserted into the relay amplifier 14 at the terminal T4, A status monitor (hereinafter, referred to as a remote monitor / control unit in the relay amplifier 14) via T5.
It is called "STM". ) Connect to 20. Identification circuit 18
Is a fixed voltage power supply 18a connected in series with a fixed resistance 18b having a fixed resistance value, and the power supply 18a and the fixed resistance 18 described above.
b and a resistor 18c connected in parallel with b
Connected to TM20. The fixed resistor 18b and the resistor 18c form a voltage dividing circuit.

In the present embodiment, the equalizer 15 is identified by changing the resistance value of the resistor 18c according to the type and equivalent amount of the equalizer 15. That is, the identification circuit 18
Then, the DC voltage from the power supply 18a is changed according to the ratio of the resistance values of the fixed resistor 18b and the resistor 18c, and the voltage is applied to the STM 20 provided inside the relay amplifier 14.

The STM 20 reads the applied voltage, identifies the connected equalizer 15 according to the value, and transmits the result as a data signal to the center 10 via the transmission line 13 to communicate with the center 10. Have. In the present invention, the power supply 18a and the fixed resistor 18b may be a constant voltage circuit and a fixed resistor provided in the relay amplifier 14. Further, the STM 20 can also have only a conversion function of reading the applied voltage, converting the value into a digital signal, and transmitting it to the center 10 as a data signal. It is also possible to decode the data signal and recognize the type and equivalent amount of the equalizer. Further, in this embodiment, the communication function of the STM 20 can be set so as to transmit the identification result of the equalizer 15 to a subcenter in the vicinity.

As a result, the center 10 recognizes the type and the equivalent amount of the equalizer based on the received data signal,
The type and equivalent amount can be displayed on a CRT (not shown) or can be printed out on a printer or the like.
Therefore, in this embodiment, the equalizer identification circuit is configured by utilizing the voltage division ratio of the resistance and the like, and the value of the resistance is changed corresponding to the equalizer to be used. The type and equivalent amount of the equalizer that is
It can be easily detected by a TM or a center.

[0013]

As described above, according to the present invention, the equalizer provided in the amplification section for amplifying a signal such as a television signal transmitted in the transmission system and compensating various characteristics of the signal, Equipped with identification means to identify the type and equivalent amount of the equalizer, it is possible to easily recognize the type and equivalent amount of the equalizer, etc. Moreover, it becomes possible to easily replace each equalizer with an appropriate one.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of an equalizer identifying apparatus according to the present invention.

FIG. 2 is a circuit diagram showing a circuit configuration of an identification circuit shown in FIG.

FIG. 3 is a diagram showing a system configuration of a CATV system.

FIG. 4 is a diagram showing a configuration of a relay amplifier shown in FIG.

[Explanation of symbols]

 10 center 11 sub center 12 subscriber terminal device 13 transmission line 14 relay amplifier 15 equalizer 16 amplifier 18 identification circuit 20 status monitor (STM)

Claims (1)

[Claims] 1. An identification unit provided in an amplification unit for amplifying a signal transmitted in a transmission system, corresponding to an equalizer for compensating various characteristics of the signal, and for identifying a type and an equivalent amount of the equalizer. A device for identifying an equalizer, comprising: