Digital Messaging Architecture
Digital messaging provides resilient, structured communications during emergency operations.
Advantages of digital messaging:
- Messages are not lost if operators miss a voice transmission
- Messages can be stored and forwarded
- Long text messages can be transmitted reliably
- Message history can be archived
- Messages can be relayed automatically between stations
This architecture uses two complementary systems:
Winlink – structured email-style messaging
JS8Call – low bandwidth store-and-forward messaging
System Overview
The WICENWA digital messaging network operates in three layers.
Internet Messaging Layer | HF Gateway Stations | Field Radio Stations
System Roles
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Station Roles
Three station types are used.
Gateway Stations Relay digital traffic across Western Australia.
Regional Relay Stations Provide regional coverage and relay traffic.
Field Stations Portable stations used by deployed teams.
Winlink System
Winlink provides email-style messaging over radio.
Capabilities:
- Send email over HF radio
- Structured emergency forms
- Attachments
- Message routing
- Message storage
Messages can be sent to:
Other Winlink users
Internet email addresses
Emergency coordination centres
Winlink Station Types
RMS Gateway
Permanent stations connected to the Winlink network.
RMS Relay
Stations that relay traffic across RF without internet.
Field Winlink Stations
Portable stations used by operators in the field.
Western Australia Winlink Topology
Suggested gateway locations:
Perth Pilbara Goldfields Southwest Midwest
These stations provide overlapping coverage across the state.
Message Flow
Field Operator
creates message
↓
Message transmitted via HF
↓
Regional Relay Station
↓
Winlink Gateway
↓
Destination
Field station
Incident command
Internet email
Suggested WA Winlink Frequencies
40m Day Operations
7.095 MHz
80m Night Operations
3.595 MHz
20m Interstate Messaging
14.095 MHz
Recommended Emergency Forms
ICS-213 General message
ICS-214 Activity log
Situation report
Resource request
JS8Call System
JS8Call provides very resilient HF messaging.
Advantages:
Extremely weak signal capability
Store-and-forward messaging
Automatic relays
Beacon capability
Position reporting
JS8Call Relay Network
The network uses automatic relays.
Example topology:
Pilbara Relay | Goldfields Relay | Perth Relay | Southwest Relay
Message Types
Direct Message
Station to station messaging.
Group Message
Message sent to a defined group.
Store and Forward
Message held until the destination station is available.
Heartbeat
Automatic signal availability reporting.
JS8Call Frequencies
40m Primary
7.078 MHz
80m Night
3.578 MHz
20m Interstate
14.078 MHz
Store and Forward Messaging
JS8Call allows messages to be stored until the receiving station becomes available.
Example:
Station A sends message to Station C
Station B receives message
Station B stores message
When Station C becomes available the message is delivered
Priority Levels
EMERGENCY
Threat to life or safety
PRIORITY
Urgent operational traffic
ROUTINE
Normal communications
Logging Requirements
All digital traffic should be logged.
Required log information:
Message number
Origin station
Destination station
Time sent
Time received
Operator
Voice and Digital Integration
Voice nets remain the primary coordination method.
Digital messaging should be used for:
Long messages
Formal reports
Resource requests
Message archiving
Voice Net Control
requests SITREP
↓
Station sends report via Winlink
↓
Net Control receives formatted message
Portable Digital Station
Recommended equipment:
HF transceiver
Laptop computer
Digital interface
Portable antenna
Battery power
Training Requirements
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Operator Training
Operators using digital messaging should be trained in:
Winlink message creation
JS8Call message routing
Radio propagation awareness
Message handling procedures