WO1997047093A1 - Apparatus for automatic sensing of line amplifier configuration for status monitoring - Google Patents

Apparatus for automatic sensing of line amplifier configuration for status monitoring Download PDF

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Publication number
WO1997047093A1
WO1997047093A1 PCT/US1997/009554 US9709554W WO9747093A1 WO 1997047093 A1 WO1997047093 A1 WO 1997047093A1 US 9709554 W US9709554 W US 9709554W WO 9747093 A1 WO9747093 A1 WO 9747093A1
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WO
WIPO (PCT)
Prior art keywords
amplifier
circuit
line
voltage level
recited
Prior art date
Application number
PCT/US1997/009554
Other languages
French (fr)
Inventor
John W. Brickell
Wayne H. Nash
Original Assignee
Scientific-Atlanta, Inc.
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Scientific-Atlanta, Inc. filed Critical Scientific-Atlanta, Inc.
Priority to US09/242,362 priority Critical patent/US6530088B1/en
Priority to BR9709407-2A priority patent/BR9709407A/en
Priority to AU32967/97A priority patent/AU3296797A/en
Priority to DE69737019T priority patent/DE69737019T2/en
Priority to EP97928802A priority patent/EP0906668B1/en
Publication of WO1997047093A1 publication Critical patent/WO1997047093A1/en

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B3/00—Line transmission systems
    • H04B3/02—Details
    • H04B3/36—Repeater circuits
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B3/00—Line transmission systems
    • H04B3/02—Details
    • H04B3/04—Control of transmission; Equalising
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N17/00—Diagnosis, testing or measuring for television systems or their details
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N7/00—Television systems
    • H04N7/10—Adaptations for transmission by electrical cable
    • H04N7/102—Circuits therefor, e.g. noise reducers, equalisers, amplifiers

Definitions

  • This invention relates to an apparatus for sensing the configuration of a cable
  • Line amplifiers are commonly used in cable television distribution systems to extend
  • Line amplifiers contain different modules
  • the functions include automatic gain control (AGC) control,
  • the technician when configuring his line amplifiers.
  • the technician uses the notes to configure
  • the line amplifier by setting jumpers on a module in the line amplifier or by entering data in
  • the invention permits a status monitoring module within a line amplifier to be
  • invention will also allow amplifier configuration changes in the field to be completed electronically and instantaneously without the technician having to change the module switch
  • the status monitor utilizes
  • A/D inputs to read DC voltages supplied by the various modules. These voltages represent
  • a controller within the line amplifier would then read the voltage change and
  • Fig. 1 is a simplified block diagram of a line amplifier implementing the invention
  • Fig. 2 is a simplified block diagram of the status monitoring device shown in Fig. 1 and incorporating the features of the invention.
  • a dual line amplifier 10 having an input port 14 coupled through cable 11 to a headend controller 12.
  • Amplifier 10 has output ports 21 and 22 coupled to subscribers 16.
  • Amplifier 10 includes amplification circuitry 20, monitoring circuitry 24 and a removable module containing reverse path circuitry 26.
  • Amplification circuitry 20 amplifies the signal on port 14 before feeding it to output ports 21 and 22.
  • Circuitry 24 contains an RF detect circuit 50, status monitor circuitry 30, indicator circuitry 64 and a modularized and removable AGC control circuit 52.
  • Monitoring circuitry 24 determines the configuration of line amplifier circuitry 20, stores this configuration and feeds a signal indicative of the configuration through reverse path circuitry 26 to headend controller 12.
  • Monitoring circuitry 24 internally generates one or more preset signals having a voltage level references. These signals are fed to status monitor circuit 30. The voltage level references of these signals change when the amplifier 10 is reconfigured, thereby providing an indication to status monitor circuit 30 of the current state of the amplifier configuration.
  • Amplifier 10 receives an RF signal on input port 14, that is fed through high/low filter 18, equalizer 32, and amplified by amplification stage 34.
  • the output of amplifier 10 is fed through variable loss inserter 36 or attenuator, and directed though coupler 38 to output amplifiers 42 and 44.
  • the output of amplifiers 42 and 44 are fed through filters 46 and 48, respectively, to output terminals 21 and 22.
  • the outputs of filters 42 and 44 are also fed to monitoring circuitry 24.
  • Monitoring circuitry 24 contains an RF detector 50 that receives the output signals of amplifiers 42 and 44. The RF detector 50 then feeds the received signal to status monitor circuit 30 and AGC control circuitry 52. As a result of the signal being received from RF detector 50, AGC control circuit 52 adjusts the attenuation of inserter 36, to vary the gain of amplification circuitry 20.
  • Status monitor circuitry 30 receives on line 61 a DC signal having a first reference voltage level.
  • the first voltage level is generated by pull down resistor 58, physically disposed on reverse path circuit 26, and pull up/pull down resistor network 60 disposed on circuitry 24.
  • Status monitor circuitry 30 receives through auto amplifier detect line 67 a DC signal having a second voltage level.
  • the second voltage level is generated by pull-up/pull down indicator circuit 64 that is also disposed on monitoring circuit 24. If removable circuity 52 is not installed, status monitor circuitry 30 is fed a DC signal having third voltage level on AGC mode line 77.
  • the third voltage level is generated by pull-up resister 79. If AGC circuit 52 is installed, status monitor circuitry is fed on line 77 a DC signal having a voltage level set by pull down resister 62, which is shunted to ground.
  • Reverse path circuit 26 includes a coupler 66, which receives the reverse path RF signal from filters 46 and 48 and feeds the RF signal through reverse amplifier 68 through reverse filter 49 to headend controller 12.
  • Status monitor circuitry 30 feeds a status signal containing an indication of the signals on lines 67, 77 and 61 as well as an indication of the detected configuration of amplifier 20. This status signal is fed through reverse amplifier 68 and reverse path filter 49 to controller 12.
  • Resistors Rv and Rg represent resistors on the motherboard of amplifier 10.
  • Rg is preferably a fixed preset value, and the value of Rv is preferably set as a function of the number of amplifier 10 outputs (i.e. single, dual, triple output).
  • Resistor 62 is disposed within removable circuit 52. Circuit 52 that may be added to the amplifier 26 either in the amplifier production or after the amplifier 26 has been installed in the field.
  • Fig 2 there is shown the status monitoring circuitry 30, having a controller 70 that reads the DC signals from the AGC circuit 52 through analog-to-digital (A D) converter 72 and DC signals from the reverse path circuit 24 through A/D converter
  • Controller reads DC signals on line 67 from A/D converter 71. Controller 70 is connected to a test interface 76, controller 70 sends and receives signals to interface 76 to permit a technician to connect test equipment thereto to indicates the AGC circuit 52 reverse path circuit 24 and indicator circuit 64 configuration. Controller 70 uses A/D converter 78 to read values from the RF detector 50, and to read and store the value of the signal from A/D connector 78 and detected RF values, into RAM memory 78.
  • modules having circuits may be connected into the line amplifier 10, and the configuration and function of these modules may be detected using an auto module type detect circuit 75 (Fig. 1).
  • Fig. 1 detect circuit 75 includes A/D converter 74, line
  • Circuit 75 monitors the type of module (i.e. distribution reverse amplifier or fiber) installed in amplifier 10 and will provide a signal to controller 70 (Fig. 2) indicating the presence/absence of such modules. Controller 70 then feeds this signal indicating the presence/absence of such modules is then fed to controller 12. This indication will aid in determining the appropriate amplifier 10 configuration for proper system configuration at the headend 12. Additional types of modules may be added in the future.
  • module i.e. distribution reverse amplifier or fiber
  • the following tables 1-3 describe exemplary voltages levels of signals detected by the status monitor circuitry 30 for amplifier 26 different configurations.
  • the status monitor circuitry 30 can read the voltage level of these signals and encode the data to inform the headend 12 of the amplifier 10 configuration.
  • Circuit 75 contains a pull-up/pull-down resistor 63 connected to line 61 to amplifier 10.
  • resistor 58 shunted to ground
  • Table 1 indicates preferred voltages for the DC signal on line 61 for the corresponding type of module types.
  • An example module type having reverse path circuitry 26 is shown in Fig. 1.
  • Line 67 is used by the circuitry 30 to enable monitoring of the type of amplifier 10 (single, dual, triple) installed. Voltage level of the DC signal read on line 67 will aid the controller 70 in determining the amplifier 10 type for proper amplifier configuration.
  • An AGC mode detect line 77 is used by the circuitry 30 to detect the presence or absence of the AGC and will enable the circuitry 30 to detect if the amplifier's AGC is in a thermal or an auto mode.
  • a pull-up resistor to 79, and a shunt resistor 62 is placed on this AGC mode line 77.
  • Resistor 62 will preferably have a value of approximately 80 ⁇ in the when circuitry 52 contains the AGC function, and will preferably have a value of approximately 20 k ⁇ when circuitry 52 contains thermal AGC and Resistor 62 is preferably open circuit when no AGC function is not present.
  • Table 3 indicates the three possible states and corresponding voltage levels for the DC signals on this AGC mode line 77.

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  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Multimedia (AREA)
  • Health & Medical Sciences (AREA)
  • Biomedical Technology (AREA)
  • General Health & Medical Sciences (AREA)
  • Monitoring And Testing Of Transmission In General (AREA)
  • Amplifiers (AREA)
  • Control Of Amplification And Gain Control (AREA)
  • Testing, Inspecting, Measuring Of Stereoscopic Televisions And Televisions (AREA)

Abstract

An apparatus for indicating the configuration of a cable television line amplifier (26). The line amplifier contains a controller (70) that senses a preset voltage on a status indication line. When the amplifier is reconfigured, such as by adding new circuits containing new functions of features, these new circuits contain resisters that are shunted to modify the preset voltage level on the appropriate status indication line. The controller senses the modified voltages and provides an indication of the new function of the new circuit to a headend through a cable television distribution system.

Description

APPARATUS FOR AUTOMATIC SENSING OF LINE AMPLIFIER CONFIGURATION FOR STATUS MONITORING
Background of the Invention
This invention relates to an apparatus for sensing the configuration of a cable
television line amplifier and more particularly to an apparatus that detects different modules
plugged into a line amplifier, and transmits the configuration of the modules to a headend
controller.
Line amplifiers are commonly used in cable television distribution systems to extend
the range that television signals are transmitted. Line amplifiers contain different modules
that have a variety of functions. The functions include automatic gain control (AGC) control,
monitoring, reverse path amplification and multiple amplified output ports. With present
cable TV distribution systems, the system operator must rely on installation notes from a
technician when configuring his line amplifiers. The technician uses the notes to configure
the line amplifier by setting jumpers on a module in the line amplifier or by entering data in
the memory of the module. Inaccurate notes could result in lost time to set up the line
amplifier station. Incorrect entry of the data into the module could result in faulty operation
of the amplifier.
Summary of the Invention
The invention permits a status monitoring module within a line amplifier to be
automatically configured upon installation without the technician having to enter data or set
jumpers within the module, regardless of the number of module types that are installed. The
invention will also allow amplifier configuration changes in the field to be completed electronically and instantaneously without the technician having to change the module switch
settings or without requiring the re-entering of data in the module. The status monitor utilizes
A/D inputs to read DC voltages supplied by the various modules. These voltages represent
the amplifier's configuration. In response to different modules being added to the line
amplifier, these voltages would automatically change upon the addition of a module with a
new option. A controller within the line amplifier would then read the voltage change and
send a signal either over the distribution system to a headend or locally to a test point on the
line amplifier indicating a change in the amplifier's configuration.
The foregoing and other objects of the present invention a well as the invention itself, may be more fully understood from the following description when read in conjunction with the accompanying drawings.
Description of the Figures
Fig. 1 is a simplified block diagram of a line amplifier implementing the invention; and Fig. 2 is a simplified block diagram of the status monitoring device shown in Fig. 1 and incorporating the features of the invention.
Description of the Preferred Embodiment
Referring to Fig. 1, there is shown a dual line amplifier 10 having an input port 14 coupled through cable 11 to a headend controller 12. Amplifier 10 has output ports 21 and 22 coupled to subscribers 16. Amplifier 10 includes amplification circuitry 20, monitoring circuitry 24 and a removable module containing reverse path circuitry 26. Amplification circuitry 20 amplifies the signal on port 14 before feeding it to output ports 21 and 22. Circuitry 24 contains an RF detect circuit 50, status monitor circuitry 30, indicator circuitry 64 and a modularized and removable AGC control circuit 52. Monitoring circuitry 24 determines the configuration of line amplifier circuitry 20, stores this configuration and feeds a signal indicative of the configuration through reverse path circuitry 26 to headend controller 12. Monitoring circuitry 24 internally generates one or more preset signals having a voltage level references. These signals are fed to status monitor circuit 30. The voltage level references of these signals change when the amplifier 10 is reconfigured, thereby providing an indication to status monitor circuit 30 of the current state of the amplifier configuration.
Amplifier 10 receives an RF signal on input port 14, that is fed through high/low filter 18, equalizer 32, and amplified by amplification stage 34. The output of amplifier 10 is fed through variable loss inserter 36 or attenuator, and directed though coupler 38 to output amplifiers 42 and 44. The output of amplifiers 42 and 44 are fed through filters 46 and 48, respectively, to output terminals 21 and 22. The outputs of filters 42 and 44 are also fed to monitoring circuitry 24.
Monitoring circuitry 24 contains an RF detector 50 that receives the output signals of amplifiers 42 and 44. The RF detector 50 then feeds the received signal to status monitor circuit 30 and AGC control circuitry 52. As a result of the signal being received from RF detector 50, AGC control circuit 52 adjusts the attenuation of inserter 36, to vary the gain of amplification circuitry 20.
Status monitor circuitry 30 receives on line 61 a DC signal having a first reference voltage level. The first voltage level is generated by pull down resistor 58, physically disposed on reverse path circuit 26, and pull up/pull down resistor network 60 disposed on circuitry 24. Status monitor circuitry 30 receives through auto amplifier detect line 67 a DC signal having a second voltage level. The second voltage level is generated by pull-up/pull down indicator circuit 64 that is also disposed on monitoring circuit 24. If removable circuity 52 is not installed, status monitor circuitry 30 is fed a DC signal having third voltage level on AGC mode line 77. The third voltage level is generated by pull-up resister 79. If AGC circuit 52 is installed, status monitor circuitry is fed on line 77 a DC signal having a voltage level set by pull down resister 62, which is shunted to ground.
Reverse path circuit 26 includes a coupler 66, which receives the reverse path RF signal from filters 46 and 48 and feeds the RF signal through reverse amplifier 68 through reverse filter 49 to headend controller 12. Status monitor circuitry 30, feeds a status signal containing an indication of the signals on lines 67, 77 and 61 as well as an indication of the detected configuration of amplifier 20. This status signal is fed through reverse amplifier 68 and reverse path filter 49 to controller 12.
Resistors Rv and Rg represent resistors on the motherboard of amplifier 10. Rg is preferably a fixed preset value, and the value of Rv is preferably set as a function of the number of amplifier 10 outputs (i.e. single, dual, triple output). Resistor 62 is disposed within removable circuit 52. Circuit 52 that may be added to the amplifier 26 either in the amplifier production or after the amplifier 26 has been installed in the field.
Referring to Fig 2, there is shown the status monitoring circuitry 30, having a controller 70 that reads the DC signals from the AGC circuit 52 through analog-to-digital (A D) converter 72 and DC signals from the reverse path circuit 24 through A/D converter
74. Controller reads DC signals on line 67 from A/D converter 71. Controller 70 is connected to a test interface 76, controller 70 sends and receives signals to interface 76 to permit a technician to connect test equipment thereto to indicates the AGC circuit 52 reverse path circuit 24 and indicator circuit 64 configuration. Controller 70 uses A/D converter 78 to read values from the RF detector 50, and to read and store the value of the signal from A/D connector 78 and detected RF values, into RAM memory 78.
In other alternate embodiments of the invention (not shown), modules having circuits (other than reverse path circuit 26) may be connected into the line amplifier 10, and the configuration and function of these modules may be detected using an auto module type detect circuit 75 (Fig. 1). Referring to Fig. 1 detect circuit 75 includes A/D converter 74, line
61 and circuit 60. Circuit 75 monitors the type of module (i.e. distribution reverse amplifier or fiber) installed in amplifier 10 and will provide a signal to controller 70 (Fig. 2) indicating the presence/absence of such modules. Controller 70 then feeds this signal indicating the presence/absence of such modules is then fed to controller 12. This indication will aid in determining the appropriate amplifier 10 configuration for proper system configuration at the headend 12. Additional types of modules may be added in the future.
The following tables 1-3, describe exemplary voltages levels of signals detected by the status monitor circuitry 30 for amplifier 26 different configurations. The status monitor circuitry 30 can read the voltage level of these signals and encode the data to inform the headend 12 of the amplifier 10 configuration. Circuit 75 contains a pull-up/pull-down resistor 63 connected to line 61 to amplifier 10. Also, different values for resistor 58, shunted to ground, will be connected to status monitoring line 61 in each of the modules to indicate different module types. Table 1 indicates preferred voltages for the DC signal on line 61 for the corresponding type of module types. An example module type having reverse path circuitry 26 is shown in Fig. 1.
Table 1: Module Option Card Types
Line 61 Voltage (V) Module Type with Vcc at +5V
1.38 - 1.64 Fiber Module + Reverse Switch
1.85 - 2.15 Fiber Module
2.33 - 2.67 Reverse Module + Reverse Switch
3.78 - 4.24 Reverse Module
Line 67 is used by the circuitry 30 to enable monitoring of the type of amplifier 10 (single, dual, triple) installed. Voltage level of the DC signal read on line 67 will aid the controller 70 in determining the amplifier 10 type for proper amplifier configuration.
Additional types of amplifiers may be added in the future. Pull-up resistor (20 kΩ, 1%) Rv should connected to this amplifier detect line 67. Different resistor values, R<j, to ground will be present on this amplifier detect line 67 in the mother board to indicate different amplifier types. Table 2 indicates the preferred different voltages on the amplifier detect line 67 and the corresponding amplifier type.
Table 2: Amplifier Station Types
Line 67 Voltage (V) Amplifier Type with power at +5V
0.20 - 0.59 Single
0.89 - 1.11 Dual
1.38 - 1.64 Triple An AGC mode detect line 77 is used by the circuitry 30 to detect the presence or absence of the AGC and will enable the circuitry 30 to detect if the amplifier's AGC is in a thermal or an auto mode. A pull-up resistor to 79, and a shunt resistor 62 is placed on this AGC mode line 77. Resistor 62 will preferably have a value of approximately 80Ω in the when circuitry 52 contains the AGC function, and will preferably have a value of approximately 20 kΩ when circuitry 52 contains thermal AGC and Resistor 62 is preferably open circuit when no AGC function is not present. Table 3 indicates the three possible states and corresponding voltage levels for the DC signals on this AGC mode line 77.
Table 3: AGC Operation
Line Voltage (V) AGC Operation
4.0 - 5.0 No AGC Installed
2.0 - 3.0 Thermal
0 - 1.0 Auto
While the principles of the invention have been made clear in the illustrated embodiments, there will be immediately obvious to those skilled in the art, many modifications are structured arrangements proportions, elements, materials, and components used in the practice of the invention, in otherwise which are particularly adapted for specific environments and operational requirements, without departing from those principals. The appended claims are therefore intended to cover and embrace any such modifications within the limits only of the true spirit and scope of the invention.

Claims

What is claimed is: 1. An apparatus for indicating the configuration of a cable amplifier, the apparatus comprising: a circuit having a status indication line with a preset voltage level; a first removable module type connected to the circuit, said first card type having means for modifying the preset voltage level on the status indication line to a voltage level different from the preset voltage level; and a controller connected to the circuit for detecting the voltage level on the status indication line and for providing an indication to a headend the card type connected to the circuit.
2. The apparatus as recited in claim 1 wherein the circuit includes an input terminal having a video signal thereon, and an output means for amplifying the signal on the input and feeding the amplified signal to the output terminal .
3. The apparatus as recited in claim 1 wherein the modifying means includes a resister connected between the status indication line and ground.
4. The apparatus as recited in claim 1 wherein the circuit is coupled to a power line, and wherein the modifying means includes a resister connected between the status indication line and the power line.
5. The apparatus as recited in claim 1 wherein said controller provides an indication of the card type from one selected from the group consisting of fiber module, reverse modules, a combination of fiber module and reverse switch, and a combination of reverse module and reverse switch.
6. The apparatus as recited in claim 1 wherein said controller provides and indication that the amplifier is from the group consisting of a single amplifier, dual amplifier and triple amplifier.
7. A cable line amplifier comprising: a circuit having a status indication line with one of a plurality of preset voltage levels, said preset voltage levels corresponding to a different function of the amplifier; and a controller connected to the circuit for detecting the voltage level on the status indication line and providing an indication of a card type connected to the circuit as a function of the voltage level detected.
8. The amplifier as recited in claim 7 further comprising a first removable card type connected to the circuit, said first card type having a resister connected to the status indication line for modifying the preset voltage level on the status indication line to a voltage level different from the preset voltage level.
9. The amplifier as recited in claim 7 where in the functions consist of one selected from the group of AGC installed, Thermal AGC installed and no AGC installed.
10. The amplifier as recited in claim 7 wherein the function indicates that the amplifier is of the type consisting of a single, a dual or a triple.
11. The amplifier as recited in claim 7 wherein the controller provides the indication to a headend over an RF link.
12. A method for indicating the configuration of a cable line amplifier comprising the steps of: providing a circuit within the line amplifier having a status indication line with one of a plurality of preset voltage levels; setting the preset voltage levels on the status indication line to correspond to a different function of the amplifier; detecting with a controller connecting to the circuit the voltage level on the status indication line; and providing an indication of the module type connected to the circuit as a function of the voltage level detected.
13. The method as recited in claim 12 further comprising the step of feeding the indication of the module type connected to a headend through a cable television delivery system.
14. The method as recited in claim 12 further comprising the steps of connecting a new module type to the circuit; modifying the preset voltage level on the status indication line to a voltage level different from the preset voltage level when the new card type is connected; and providing an indication of the new module type when connected to the circuit.
15. The method as recited in claim 14 further comprising the step of providing on the new module type a resister connected to the status indication line; and modifying the preset voltage level on the status indication line with the resister.
16. The method as recited in claim 14 further comprising the step of indicating that the module consists of one selected from the group of AGC installed, thermal AGC installed and no AGC installed.
17. The method as recited in claim 14 further comprising the step of indicating that the amplifier is of the type consisting of a single, a dual or a triple.
18. The method as recited in claim 14 further comprising the step of indicating that the module type is one selected from the group consisting of fiber module, reverse modules, a combination of fiber module and reverse switch, and a combination of reverse module and reverse switch.
PCT/US1997/009554 1996-06-03 1997-06-02 Apparatus for automatic sensing of line amplifier configuration for status monitoring WO1997047093A1 (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
US09/242,362 US6530088B1 (en) 1996-06-03 1997-06-02 Apparatus for automatic sensing of line amplifier configuration for status monitoring
BR9709407-2A BR9709407A (en) 1996-06-03 1997-06-02 Device for automatic detection of line amplifier configuration for status monitoring.
AU32967/97A AU3296797A (en) 1996-06-03 1997-06-02 Apparatus for automatic sensing of line amplifier configuration for status monitoring
DE69737019T DE69737019T2 (en) 1996-06-03 1997-06-02 DEVICE FOR AUTOMATICALLY DETECTING THE LINE AMPLIFIER CONFIGURATION FOR STATE MONITORING
EP97928802A EP0906668B1 (en) 1996-06-03 1997-06-02 Apparatus for automatic sensing of line amplifier configuration for status monitoring

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US1900796P 1996-06-03 1996-06-03
US60/019,007 1996-06-03

Publications (1)

Publication Number Publication Date
WO1997047093A1 true WO1997047093A1 (en) 1997-12-11

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US (1) US6530088B1 (en)
EP (1) EP0906668B1 (en)
AU (1) AU3296797A (en)
BR (1) BR9709407A (en)
DE (1) DE69737019T2 (en)
ES (1) ES2276428T3 (en)
WO (1) WO1997047093A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002039733A2 (en) * 2000-10-27 2002-05-16 Scientific-Atlanta, Inc. Frequency agile adaptive automatic gain control circuit

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7039942B2 (en) * 1998-08-14 2006-05-02 Cableserv Electronics, Ltd. Pad adjustable equalizer for two way cable transmission
TW512631B (en) * 1999-05-24 2002-12-01 Sharp Kk Signal distribution circuit
JP4249337B2 (en) * 1999-06-29 2009-04-02 富士通株式会社 Interactive CATV system
US6779197B1 (en) * 1999-07-02 2004-08-17 Adc Telecommunications, Inc. Reverse path upstream signaling for status monitoring
US7088975B1 (en) * 2002-01-04 2006-08-08 Broadcom Corporation Automatic gain control system and method using multiple local AGC loops
US20030151699A1 (en) * 2002-02-14 2003-08-14 Pokorski Joseph D. Double remote system
US11812072B2 (en) * 2021-11-23 2023-11-07 Applied Optoelectronics, Inc. Node housing with lid-based mounting of node components for use in a broadband distribution network

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5555015A (en) * 1995-03-20 1996-09-10 Intrinzix Technologies, Inc. Wireless two way transmission between center and user stations via a relay
US5598418A (en) * 1994-11-10 1997-01-28 Advanced Micro Devices Inc. Repeater status LED array interface
US5657154A (en) * 1995-04-12 1997-08-12 Nec Corporation Monitoring system for all optical regenerators

Family Cites Families (29)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3806814A (en) 1972-04-26 1974-04-23 Hughes Aircraft Co Phantom subscriber
FR2444983A1 (en) 1978-12-22 1980-07-18 Fillot Jean Jacques SYSTEM FOR MONITORING AND REGULATING A TRANSMISSION LINK
JPS56131214A (en) 1980-03-17 1981-10-14 Matsushita Electric Ind Co Ltd Catv device
JPS57196678A (en) 1981-05-27 1982-12-02 Pioneer Electronic Corp Table network managing mechanism in catv system
US4520508A (en) 1982-12-21 1985-05-28 General Instrument Corporation Subscriber terminal for monitoring radio-frequency signal ingress into cable television systems
CA1266707A (en) 1985-12-16 1990-03-13 Steve S. Yang Method of calibrating and equalizing a multi-channel automatic gain control amplifier
JPH0622353B2 (en) * 1988-11-28 1994-03-23 富士通株式会社 Transmission line monitoring method
US4937535A (en) 1988-12-29 1990-06-26 Genrad, Inc. Calibration method and programmable phase-gain amplifier
FI83576C (en) 1989-02-10 1991-07-25 Nokia Mobira Oy Procedure and switching arrangement for controlling the volume of one mobile phone
US5020134A (en) 1989-05-19 1991-05-28 Pecaut Steven C CATV signal distribution system and local status monitor therefor
CA2033763C (en) * 1990-01-18 1994-11-01 Timothy Burke Distributed amplifier network management system
JPH03248659A (en) * 1990-02-27 1991-11-06 Yagi Antenna Co Ltd Trunk amplifier status supervisory system
FR2665988B1 (en) 1990-08-14 1996-11-22 Cit Alcatel METHOD AND DEVICE FOR AUTOMATIC GAIN CONTROL OF A VARIABLE GAIN AMPLIFIER AND THEIR APPLICATION TO THE GAIN CONTROL OF A TUNER, PARTICULARLY FOR A VIDEO COMMUNICATION NETWORK.
SG49266A1 (en) * 1992-05-19 1998-05-18 Thomson Multimedia Sa Method and apparatus for device control by data transmission in TV lines
JP3320452B2 (en) * 1992-07-15 2002-09-03 沖電気工業株式会社 Monitoring and control method for optical repeaters
FR2694813B1 (en) * 1992-08-12 1994-11-04 Pierre Itibar Network remote control and maintenance system.
US5367571A (en) * 1992-12-02 1994-11-22 Scientific-Atlanta, Inc. Subscriber terminal with plug in expansion card
JPH07176813A (en) * 1993-12-17 1995-07-14 Fujitsu Ltd Optical fiber amplifier
US5488413A (en) * 1994-06-14 1996-01-30 Xel Communications, Inc. CATV telephony system using subsplit band for both directions of transmission
US5513029A (en) * 1994-06-16 1996-04-30 Northern Telecom Limited Method and apparatus for monitoring performance of optical transmission systems
US5424677A (en) 1994-07-01 1995-06-13 Fluke Corporation Common mode error correction for differential amplifiers
WO1996008925A1 (en) * 1994-09-12 1996-03-21 Scientific-Atlanta, Inc. Cable television apparatus employing two-way communication
US5710653A (en) * 1995-03-06 1998-01-20 Fiber Optic Network Solutions Corp. Linear multi-output optical transmitter system
JP3611631B2 (en) * 1995-03-20 2005-01-19 Ｋｄｄｉ株式会社 Line monitoring method and line monitoring apparatus
JPH08278523A (en) * 1995-04-05 1996-10-22 Hitachi Ltd Light amplifier
KR0150757B1 (en) * 1995-12-20 1998-11-02 양승택 Line driving system complying with transmission medium characteristics
US5835844A (en) * 1995-12-29 1998-11-10 General Instrument Corporation Bidirectional CATV system having losses for equalizing upstream communication gain
US5845190A (en) * 1996-02-28 1998-12-01 Ericsson Raynet Cable access device and method
US6002671A (en) * 1997-09-03 1999-12-14 Fluke Corporation Test instrument for testing asymmetric digital subscriber lines

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5598418A (en) * 1994-11-10 1997-01-28 Advanced Micro Devices Inc. Repeater status LED array interface
US5555015A (en) * 1995-03-20 1996-09-10 Intrinzix Technologies, Inc. Wireless two way transmission between center and user stations via a relay
US5657154A (en) * 1995-04-12 1997-08-12 Nec Corporation Monitoring system for all optical regenerators

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP0906668A4 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002039733A2 (en) * 2000-10-27 2002-05-16 Scientific-Atlanta, Inc. Frequency agile adaptive automatic gain control circuit
WO2002039733A3 (en) * 2000-10-27 2002-11-28 Scientific Atlanta Frequency agile adaptive automatic gain control circuit
US6567118B1 (en) 2000-10-27 2003-05-20 Scientific-Atlanta, Inc. Frequency agile adaptive automatic gain control circuit

Also Published As

Publication number Publication date
DE69737019T2 (en) 2007-05-31
EP0906668B1 (en) 2006-11-29
AU3296797A (en) 1998-01-05
BR9709407A (en) 1999-09-28
DE69737019D1 (en) 2007-01-11
EP0906668A1 (en) 1999-04-07
US6530088B1 (en) 2003-03-04
EP0906668A4 (en) 1999-07-28
ES2276428T3 (en) 2007-06-16

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