JP2669306B2 - CATV network monitoring system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CATV network monitoring system, and more particularly to a monitoring system having a function of monitoring an analog value indicating a state of a transmission path device to be monitored.

[0002]

2. Description of the Related Art A conventional CATV network monitoring system includes a plurality of terminal devices built in a plurality of transmission path devices to be monitored, and a plurality of RF-MODEMs (modem-demodulators) connected to the terminal devices. And a monitoring device connected to the RF-MODEM via a communication control device. As the transmission line device, a relay amplifier, a power supply device, and the like can be considered.

[0003] The monitoring apparatus performs monitoring polling on terminal equipment built in the transmission path equipment. The terminal device that has received the monitoring polling is the input / output level of the corresponding transmission line device,
The input voltage, the DC load current value, and the like are measured, and a measurement result signal representing the measured value is transmitted to the monitoring device via the RF-MODEM and the communication control device. An allowable range (normal range) of measurement values that can be taken when the transmission line device is in a normal state is set in the monitoring device in advance. The monitoring device determines whether or not the measurement value indicated by the transmitted measurement result signal is within an allowable range, and outputs an alarm if the measured value is out of the allowable range.

Further, there is the following prior art. Japanese Patent Application Laid-Open No. Sho 62-274841 (hereinafter referred to as Prior Art 1) provides a function of determining an operation state by itself from a measurement value measured by a repeater so that a message representing only the determination result is transmitted to a relay station. A CATV repeater monitoring system is disclosed in which a relay monitoring station can collect the data in a short time to improve the system. Japanese Patent Application Laid-Open No. 60-208192 (hereinafter referred to as "prior art 2") discloses a method of centrally monitoring fault information of each branch amplifier according to a center command from a bidirectional data transmission device using a CATV cable network. This enables CAT to detect abnormalities early in the event of a failure and repair them in a short time.
A failure detection method in a V system is disclosed. Further, Japanese Unexamined Patent Publication No. 64-64483 (hereinafter referred to as prior art 3) discloses a center centralized monitoring control device.
A CATV line monitoring and control system has been disclosed, in which centralized monitoring of each monitoring information in each relay amplifier and control of its upstream branch circuit switch enable immediate detection of an interfering wave mixing point and accurate separation. There is.

[0005]

SUMMARY OF THE INVENTION The above-mentioned conventional CAT
In the V network monitoring system, in the monitoring device,
Since the abnormality is determined based on whether the obtained measured value is within the normal range set in advance, a false report is output due to a measurement error, and even if the measured value temporarily deviates from the normal range, the transmission path is Even if there is no possibility of causing an abnormality in the equipment, there is a problem that it is judged as abnormal when the measured value is out of the normal range. Further, it is necessary to set the normal range to be set in the monitoring device in consideration of the measurement error, the error at the time of initial setting, and the difference between the normal ranges of the transmission line devices.

An object of the present invention is to provide a CATV network monitoring system capable of predicting the occurrence of an abnormality by monitoring a temporal change of a measured value and outputting an alarm.

[0007] None of the prior arts 1 to 3 disclose that a change in the measured value is monitored over time to predict the occurrence of an abnormality and output an alarm. Absent.

[0008]

A CATV network monitoring system according to the present invention includes a first storage device for storing an initial value of a measured value of a transmission path device to be monitored, and a first storage device connected to the first storage device. A status monitor unit that is built in the transmission path device to be monitored, obtains a state of the transmission path device, and outputs a difference between a current measurement value indicating the state and an initial value stored in the first storage device; A monitoring device that detects a time change of the difference sent from the status monitor unit and outputs an alarm when the difference value reaches a predetermined state, and calculates a difference and a monitoring device controlled by the monitoring device. A second storage device for storing the result.

Further, the above monitoring device sets an upper limit value and a lower limit value of the allowable variation of the measured value with respect to the initial value, and outputs an alarm when the difference is equal to or more than the upper limit value or equal to or less than the lower limit value. desirable. Further, the monitoring device is
It is preferable that the average value of the differences is calculated a predetermined number of times, and an alarm is output when the average value is positive or negative continuously for a predetermined number of times.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

Referring to FIG. 1, a CATV network monitoring system according to an embodiment of the present invention includes a monitoring device 1.
, A measured value storage device 2, a communication control device 3, a monitoring polling timer 4, an RF-MODEM 5, a status monitor unit 6, and an initial value storage device 7. The monitoring device 1 has a function of monitoring a time change of the measurement value measured by the status monitor unit 6. The measurement value storage device 2 stores measurement values transmitted from terminal devices (not shown) incorporated in a plurality of transmission path devices (not shown) to be monitored. The status monitor unit 6 is built in each of the transmission path devices and has a function of measuring the output level of the transmission path device and communicating with the monitoring device 1. The initial value storage device 7 stores an initial value of the measured value.

Next, the operation of the CATV network monitoring system shown in FIG. 1 will be described with reference to FIGS. 2 and 3.

At the end of the installation of the transmission line equipment and the on-site adjustment, the measured value of each monitoring item is stored as an initial value Xi in the initial value storage device 7 attached to the transmission line equipment to be monitored. In addition, the monitoring apparatus 1 sets in advance an upper limit value Vdu and a lower limit value Vdl of a variation with respect to an initial value of a measurement value allowed in each monitoring item.

In this embodiment, the status monitor unit 6 has SMT001, SMT002,.
Suppose there is xxx. Upon receiving the monitoring polling message from the monitoring device 1, the SMT001 receives the current measured value X
(N) The difference x (n) = Xi−X (n) between the stored initial value Xi and (n = 1, 2, 3,...) Is transmitted to the monitoring device 1.

In the monitoring device 1, after incrementing the variable n (n = n + 1) (step S1), SMT001
And receives the difference x (n) of the measurement values from (step S2)
It is determined whether the difference x (n) is within the range of Vdl <x (n) <Vdu (step S3). The difference x (n) is Vdu ≦
If x (n) or x (n) ≦ Vdl (NO in step S3), the monitoring device 1 outputs an alarm (step S3).
4). If x (n) satisfies Vdl <xn <Vdu (YES in step S3), the monitoring device 1 stores x (n) in the measurement value storage device 2.

When receiving the difference of n = N (YES in step S5), the monitoring device 1 calculates an average value xave (1) of x (1) to x (N) (step S6) and obtains the measured value. It is stored in the storage device 2. Similarly, SMT001 is x (N +
1) to x (2N) are transmitted, and the monitoring device 1 calculates their average value xave (2) and stores it in the measurement value storage device 2.

The monitoring device 1 stores the average value xave (m) and the average value xave (m-, which are stored in the measurement value storage device 2.
1) Difference Δxave (m) = xave (m) −xa
ve (m-1) is calculated and stored in the measured value storage device 2. After resetting the variable n to 0 and incrementing the variable m (m = m + 1) (step S8), if m is equal to M (YES in step S9), the monitoring device 1 sets the average value of M consecutive times. On the other hand, Δxave (m)> 0 or Δxave with respect to the average value of M consecutive times
When (m) <0 (YES in step S10), an alarm is output (step S11).

Another status monitor unit, SMT0
, SMTxxx are performed in the same manner (steps S12 and S13).

Although the present invention has been described with reference to the embodiments, the present invention is not limited to the embodiments, and it is needless to say that various changes / modifications can be made without departing from the spirit of the present invention. .

[0020]

As described above, according to the present invention, by analyzing the tendency of the change in the measured value with the passage of time, it is possible to early detect an abnormality in the transmission line device before causing a failure in the system. There is an effect. Further, in the present invention, since the relative value with respect to the initial value is monitored for each transmission line device, false alarm due to measurement error can be reduced. In particular, the present invention is effective for monitoring a DC load current value of a relay amplifier having a device difference in measured values.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a CATV network monitoring system according to an embodiment of the present invention.

FIG. 2 is a flowchart for explaining the operation of the monitoring device in FIG. 1;

FIG. 3 is a time chart showing an example of a calculation result in the monitoring device in FIG. 1;

[Explanation of symbols]

 1 Monitoring Device 2 Storage Device 3 Communication Control Device 4 Monitoring Polling Timer 5 RF-MODEM 6 Status Monitor Unit 7 Storage Device

Claims (3)

(57) [Claims] 1. A first storage device for storing an initial value of a measured value of a transmission path device to be monitored, and a first storage device connected to the first storage device and built in the transmission path device to be monitored for the transmission. obtaining the state of the road equipment, and status monitor unit for outputting a difference between the initial value stored in the current measurement value and the first storage device representing the state, said that has been sent from the status monitor unit A monitoring device that detects a time change of the difference and outputs an alarm when the difference value is out of a predetermined range; and a second device that is controlled by the monitoring device and stores the difference and a calculation result of the monitoring device. A CATV network monitoring system, comprising: the storage device of claim 1; 2. The monitoring device according to claim 1, wherein an upper limit value and a lower limit value of an allowable variation of the measured value with respect to an initial value are set, and an alarm is output when the difference is equal to or more than the upper limit value or equal to or less than the lower limit value. The CATV network monitoring system according to claim 1, wherein 3. An initial value of a measured value of a transmission path device to be monitored.
Storage device for storing the data, and the transmission path device to be monitored, which is connected to the first storage device
The status of the transmission line device is built into the transmitter, and the status is displayed.
The current measurement value and the value stored in the first storage device.
Status monitor unit that outputs the difference from the initial value
And the difference sent from the status monitor unit.
Minute change, the average value of the difference is calculated a predetermined number of times, and a monitoring device that outputs an alarm when the average value is positive or negative for the predetermined number of times continuously, and is controlled by the monitoring device. The difference and the monitoring device
A second storage device for storing the calculation result of the device, and a CATV network monitoring system.