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October 28, 2002 International Loran Association

Modernization of Nii Jima Transmitter Control

Presented by Michael Weisenbloom

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Goals and Objectives

• Reduce cost of ownership– Remote capability for unattended transmitter operation– Modern, reduced component count for greater reliability and tighter

integration

• Improve operator control and interface– Graphical user interface display and control at local and remote

locations – Time synchronization to UTC-USNO via built-in GPS

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Goals and Objectives

• Provide easy upgrade path for current systems– Existing transmitter cables and equipment fully compatible– Fits in existing footprint and power requirements

• Provide for future upgrades and growth– Flexible system architecture with embedded software and

programmable hardware, each with designed in reserve– Commercial off-the-shelf modules and subcomponents

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Transmitter Control System Diagram

Load BatteryLineOn On

BatterySmartBoost

ReplaceBattery

Test

Load BatteryLineOn On

BatterySmartBoost

ReplaceBattery

Test

06:05:02

06:05:02

27

27

Accufix 7520 Transmitter ControlSubsystem (TCS)

Accufix 7523 LoranTimer Subsystem (LTS)

Accufix 7500 Transmitter Control Unit (TCU)

Nii JimaReplace 4 rack Control Console Unit with new 3 rack software controlled

Transmitter Control Unit

ChibaReplace 1 rack Remote Control Unit

rack with PC workstation and graphical remote control software

Load BatteryLineOn On

BatterySmartBoost

ReplaceBattery

Test

Load BatteryLineOn On

BatterySmartBoost

ReplaceBattery

Test

A B C D E F G HSELECTED

ON-LINE

AC Power

New graphical display and user interface

Remote networked interface for unattended transmitter operation

NTT lease line network

Time sync to UTC via built-in GPS

Redundant PC workstation with UPS back-up

UPS and battery backup

Direct connection to existing transmitter cables

Similar installation upgrades also planned for Gesashi and Tokatibuto stations in NW Pacific chain for 2003 and 2004

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Transmitter Control Unit

• Replace existing CCU with new Transmitter Control Unit (TCU)– 3 Rack System

– Modern off-the-shelf parts

– Software and graphical user interface control

– UPS and battery backup

– Ethernet/HUB interface to NTT leased network for Chiba remote control

Load BatteryLineOn On

BatterySmartBoost

ReplaceBattery

Test

Load BatteryLineOn On

BatterySmartBoost

ReplaceBattery

Test

06:05:02

06:05:02

27

27

Accufix 7520 Transmitter ControlSubsystem (TCS)

Accufix 7523 LoranTimer Subsystem (LTS)

Accufix 7500 Transmitter Control Unit (TCU)

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Loran Timer Subsystem (LTS)

• Loran Timer Assemblies– Generates Loran pulse timing

(MPTs)

• UTC Sync Assemblies- Provides UTC synchronized

timing source from GPS

06:05:02

06:05:02

27

27

Accufix 7523 LoranTimer Subsystem (LTS)

Loran Receivers(Locus)

Loran Timer Assemblies (LTAs)

UTC Sync Assemblies (USAs)

Cesium Units

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Loran Timer Assembly (LTA)

Circuit board

Top View Inside Chassis

19”

Power Supply

Front Panel View

3U

• Generates dual-rate Loran pulse timing

• Automatic detection and adjustment of transmitted pulse reference

• Local and remote user controlled phase adjust

• Single board design with embedded software and logic

• 19” wide by 3U rack mounted assembly

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UTC Sync Assembly

• Cesium clock synchronization to GPS UTC

• Time-of-coincidence generation and error checking

• Time-of-day setting and error checking with external GPS

• Single board design with embedded software and logic

• 19” wide by 2U rack mounted assembly

Circuit board

Top View Inside Chassis

19”

Power Supply

Front Panel View

2U

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Loran Timer Subsystem Interconnect Diagram

LoranReceiver(Locus)

LoranReceiver(Locus)

Sync

Multipulse Triggers (MPT)

Multipulse Triggers (MPT)

Modulation Data

Modulation Data

Time ofTransmission

Controller(Optional)

EurofixProcessor(Optional)

EurofixProcessor(Optional)

Time ofTransmission

Controller(Optional)

LoranTimer

Assem.(LTA)

Timing

Timing

UTCSync

Assem.(USA)

GPS Rx

5Mhz

Cesium RS232

1PPS,RS232

1PPS,RS232

UTCSync

Assem.(USA)

1PPS,RS232

1PPS,RS232

GPS Rx

Cesium

5Mhz

RS232

Power

Power

LoranTimer

Assem.(LTA)

PCI

RS232 (2)

RS232

PCI

RS232 (2)

To/From TransmitterControl Console #1

in TCU

To/From TransmitterControl Console #2

in TCU

To/FromTCC #1, #2

To/FromTCC #1, #2

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Transmitter Control Subsystem (TCS)

5U

1U

9U

4U

1U

BLANK

BLANK

10U

1U

2U

5U

1U

9U

4U

1U

BLANK

BLANK

10U

1U

2U

Alarm/Status Panel

Touchscreen Display

Retractable Keyboard Tray

TCA (Transmitter Control Assembly)

AC Input Power Phase Switcher

UPSFan

Assembly

Cable Connector Assembly (CCA)

TCC (Transmitter Control Console) #1

TCC (Transmitter Control Console) #2

Redundant Transmitter Control Consoles

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Chiba Control Workstation for Nii Jima

• Install new control workstation at Chiba– Remote operator control of

Nii Jima TCU and transmitter

– Graphical user interface

– Ethernet/HUB interface to NTT leased network

Load BatteryLineOn On

BatterySmartBoost

ReplaceBattery

Test

Load BatteryLineOn On

BatterySmartBoost

ReplaceBattery

Test

A B C D E F G HSELECTED

ON-LINE

AC Power