October 28, 2002 International Loran Association

, Inc.

Development of a Next Generation Transmitter

Control System

Presented by: Terry Yetsko BCO, Inc.

George Mukai BCO, Inc.

Erik Johannessen Megapulse, Inc.

, Inc.

Need for Modernized Transmitter Control

• Significant upgrade required both in functional capability and technology.

• Required as part of Loran recap effort.– Present SSX control console over 20 years old.

• Not supportable long term.

• Maintainability/reliability do not lend themselves to unattended operation.

– Present SSX control console does not support required Loran enhancements.

• Present architecture robust but inflexible.

• System demands on the system are greater in the future.– Better timing.– Better envelope control.

, Inc.

TCS Design Philosophy

• Retained Existing Partitioning at System Level– GFE Loran Timer, Remote Control, Control Console and Power

Distribution– XMTR Components - PGAs, Output & Coupling Networks, RF Switch

• Retained Existing Functionality– Replaced TOPCO, PATCO, SDA and Display Units with

modernized/updated sub-assemblies

• Incorporated New Functionality– Support for Additional Drive Half Cycles– Dynamic Re-Assignment of HCGs– Real-Time Loran Signal Quality Analysis (SQA)

• Allowed for Future Capabilities– Intrapulse Frequency Modulation (IFM)– Enhanced Data Analysis

, Inc.

TCS Design Philosophy

5U

1U

9U

5U

1U

BLANK

BLANK

7U

4U

2U

5U

1U

9U

1U

BLANK

BLANK

2U

BLANK

4U

BLANK

5U

7U

Rate A & BMPT, Set/Reset &5 MHz

MTS 1 - 72

Antenna Switch

Output Network (Unit 4)

Coupling Network (Unit 5)

Output Network (Unit 4)

Coupling Network (Unit 5)

RF Switch

Pulse Generator

(Unit 3)

Pulse Generator

(Unit 3)

Antenna

DHC Feedback

Antenna Current Feedback

FromTimer(Unit 1)

Switch Control

MTS Timing Signals

PATCOTOPCO

SDA

DHCCurrent Pulse

Switch Network(Unit 6)

RF Output

RF Output

DAR ACD Phase Disch Trig Meg ReF

, Inc.

TCS Block Diagram

AN/FPN-65 Loran-C Timer Heartbeat

Transmitter Control

Assembly (TCA #1)

Transmitter Control

Assembly (TCA #2)

Keyboard/Mouse

Alarm Panel

Timing

TimingTiming Signals

Control/ Status

Remote Control/

Monitoring

Power Distribution

TCC Power Distribution

w/UPS

Prime Power

Remote Control/

Monitoring

TCC (Transmitter Control Console) #1

TCC (Transmitter Control Console) #2

Control Connector Assembly (36 HCGs)

Timing Signals

(Redundant)

3 Phase Power

Monitor

3 Phase Power

Monitor

Redundant Switch

Redundant Switch

TCC Power Distribution

w/UPS

Power

Power

Control/Status

Status

Status

Control/Status

UPSPwr

UPSPwr

Status Graphics Display

Video

Touchscreen

Graphics Display

Video

Touchscreen

Graphics Display

Video

Touchscreen

Keyboard/Mouse

Timing, Control, Status

Antenna Feedback DHC Feedback

Antenna Feedback DHC Feedback

Status

Hub

Phase A

Phase B

3 PhaseGroup I & II HCGs (qty 36)

Group I & II Coupling Networks (3)

Group I & II Output Networks

RF Switch

Fire Detection

Group I & II HCGs

Group I & II Coupling Networks

Printer (Optional)

Phase A

Phase B

Control/ Status

Expansion Control

Connector Assembly (36 HCGs)

Fire Detector

Blower

Up to 36 HCGs

37 to 72 HCGs

Alarm Panel

Blower

Fire Detector

A

B

C

D

CA DB

Up to 36 HCGs

37 to 72 HCGs

Hub

RedundantTiming, Control, Status

, Inc.

Transmitter Control Subsystem (TCS)

5U

1U

9U

5U

1U

BLANK

BLANK

7U

4U

2U

5U

1U

9U

1U

BLANK

BLANK

2U

BLANK

4U

BLANK

5U

7U

Alarm/Status Panel

Thinview-15-SS9-RM-SP410 15” Touchscreen Display

Retractable Keyboard TrayKontron(ICS) RMX-EKB104

TCA (Transmitter Control Assembly)

APC SU042-2 Redundant Switch

APC Smart-UPS 3000 RM 5U

Rear Mount Fan Assemblies

Control Connector Assembly(s)

TCC (Transmitter Control Console) #1

TCC (Transmitter Control Console) #2

Redundant Transmitter Control Consoles

Fire DetectAssys

, Inc.

TCA – Block Diagram

Slot-1Single Board Computer

(SBC)

VMEbus Backplane

Displayw/Touchscreen

Graphics

Keyboard/Mouse

AlarmPanel

Rate A Processor, HCG/Serial Data Stream Control

DigitalInput/OutputModule(s)

MTS

AntennaFeedback

RedundantSwitch

Printer(Opt.)

Parallel

Serial

Commands- RF Switch- Ant Tune

UPSSerial

DHCFeedback

Rate B Processor

TailbiterTriggers

Status/Faults- RF Switch- HCG- Output Net- Coupling Net- TB Mon

BackupTCA

Heartbeats

LoranTimer

SyncSync

SignalConditioning

Signal Conditioning

Serial

PS/2

RemoteInterface

Serial

Status

Atten

HUB

Atten

Divider Divider PowerMonitor

HUB

, Inc.

TCA – VME Chassis20 Slot Chassis

Five COTS (Commercial-Off-

The-Shelf) 6U VME Cards

Three COTS PMC (PCI Mezzanine Card) Modules

Two Custom VME Cards: One Custom PCI Daughter Card for HCG Control One Custom VME Card for Signal Conditioning, Qty 4

AB

C

DE

Five Functional Groups

, Inc.

HCG/Serial Data Stream Control Group (HCG/SDSC)

• Majority of PATCO, TOPCO and Signal Distribution Assembly (SDA) functionality combined into one (1) custom VME Card married to:

Motorola MVME 2431-3 750 MHz PPC Processor

<and>

ICS-550 65 MHz Dual Channel Data Acquisition Module.

• PATCO functions: timing and triggering, failsafe blanking, DHC feedback analysis, MTS data stream generation, polarity control, antenna feedback analysis and antenna tuning

• TOPCO functions: fault monitoring and analysis

• SDA functions: MTS data stream multiplexing

PATCO

TOPCO

SDA

, Inc.

HCG/SDSC Block Diagram

PCI Local Data

Data Acquisition

Module

DHCFeedback

Attenuator(chassis mount)

VME Bus

44b

4b

8 10

DAQ

11 13

HCG/Seri

al Con

trolle

r

Custom

PCI

Daugh

ter C

ardCus

tom S

ignal

Condit

ioning

Card

s

Blanking Control Timing

Generator

Programmable Delay

Generators Mux

MPT AMPT B

Set/Reset

72...

Serial DataStreams

Parallel I/O

200 kHz Clocks

MeasurementTrigger & Clock

Signal Conditioning

Polarity Control

5

8,10,11,13

Tailbiter Monitor Control

Delay Enable

Tailbiter Triggers

Serial DataStreams

Rate A HCG/Serial Data Stream Controller

%

Rate B HCG/Serial Data Stream Controller

Data Acquisition

Module

7b

4 5

7b

DAQ

HCG/Seri

al Con

trolle

r

7

PCI Bridge

7 AntennaFeedback

Attenuator(chassis mount)

%

PCI Local Data

Data Acquisition

Module

DHCFeedback

Attenuator(chassis mount)

VME Bus

44b

4b

8 10

DAQ

11 13

HCG/Seri

al Con

trolle

r

Custom

PCI

Daugh

ter C

ardCus

tom S

ignal

Condit

ioning

Card

s

Blanking Control Timing

Generator

Programmable Delay

Generators Mux

MPT AMPT B

Set/Reset

72... 72...

Serial DataStreams

Parallel I/O

200 kHz Clocks

MeasurementTrigger & Clock

Signal Conditioning

Polarity Control

5

8,10,11,13

Tailbiter Monitor Control

Delay Enable

Tailbiter Triggers

Serial DataStreams

Rate A HCG/Serial Data Stream Controller

%

Rate B HCG/Serial Data Stream Controller

Data Acquisition

Module

7b

4 5

7b

DAQ

HCG/Seri

al Con

trolle

r

7

PCI Bridge

7 AntennaFeedback

Attenuator(chassis mount)

%

, Inc.

TCS – Main Station Control Screen

, Inc.

TCS – Station Configuration Screen

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TCS – Loop Maintenance Screen

, Inc.

TCS – Engineering Screens

, Inc.

Control Loop Algorithm - Amplitude

• Current system uses ratios to a reference voltage to control all 4 DHC amplitudes– Both ratios and reference voltages

are thumbwheel selectable.– Adjustments to the reference voltage

controls output power.

• Ratios still utilized for DHC 2, 3 & 4.– Ratios are contained in ECD table.

• Measurements made on 6th pulse in group (like current system).– Potential expansion to analyze all pulses (droop compensation).

• DHC 1 adjusted based on power indication from antenna feedback.– Control loop is now closed based on system output as opposed to interim

feedback (DHC feedback).– Control loops now compensate for variability in network cabinets.

-25000

-20000

-15000

-10000

-5000

0

5000

10000

15000

20000

25000

750 950 1150 1350 1550 1750 1950

DHC 2,3 & 4 controlled based on ratio to DHC 1

DHC 1 controlledbased on antenna feedback analysis Ratio 2

Ratio 3

Ratio 4

, Inc.

Control Loop Algorithm - Timing

• Original timing loops utilized hardware implementation based on 60 % points. – Software algorithm currently maintains

that approach but could be enhanced to be less sensitive to pulse shape.

• Configurable items provide flexibility.– Averaging period and adjustment step size– DHC Timing Position

• Currently set to offset DHC 2,3,4 150nsec, 100 nsec and 100 nsec respectively to improve phase modulation.

– Potential expansion to base offsets either on ECD selection or analysis of antenna feedback.

• Fixed offsets added to DHC timing for individual pulses in each group.

– Potential enhancement to base offset on feedback analysis of individual pulses.

, Inc.

Control Loop Algorithm - Tuning

• Original antenna tuning based on 5th to 12th 0-crossing.

• Analysis showed more accurate measurement achieved starting at 6th 0-crossing.

• Algorithm modified to tune based on 6th to 12th crossing.– Crossings are configurable to provide

flexibility.– Similar slope crossings chosen to

minimize error caused by feedback offset.

• Averaging period and adjustment time also configurable.

96,000

97,000

98,000

99,000

100,000

101,000

102,000

103,000

104,000

1 3 5 7 9 11 13 15 17 19

S eries 3

96,000

97,000

98,000

99,000

100,000

101,000

102,000

103,000

104,000

1 3 5 7 9 11 13 15 17 19

S eries 3

-30000

-20000

-10000

0

10000

20000

30000

1800 2000 2200 2400 2600 2800 3000 3200 3400

Offset Error

-30000

-20000

-10000

0

10000

20000

30000

1800 2000 2200 2400 2600 2800 3000 3200 3400

Offset Error

, Inc.

SQA Functionality

• Hardware implementation using 65 MHz Data Acquisition Module provided capability for detailed analysis of antenna feedback.– Amplitude control loops are partially based on antenna feedback.– Lordac functionality is embedded in the control system software.– Analysis of signal quality is used in redundancy and failure

analysis decisions.

• Potential enhancements involve analysis of antenna feedback being applied to:– Pulse to pulse timing and amplitude control.– ECD control.

, Inc.

MVME 2400 Data Processing – Dual Rate

, Inc.

MVME 2400 Data Processing – Single GRI

, Inc.

Summary

• High utilization of COTS components.– Open system architecture.

• Partitioning and functional capability provides:– Performance required for the new system.– Allows easy integration into legacy systems.

• Remote/unattended operation.

• Graphical user interface provides:– Ease of use.– High visibility into system operation.– Flexible control.

• Enhanced data analysis and control.– Horsepower for expansion/enhancement.