Where can the IMT 9704 be used? Mountain rescue, maritime and monitoring

The 9704 fits wherever there is no mobile network but you need a photo, a voice clip or a larger file: mountains, the open sea, remote sites, and disaster areas where ground networks are down.

Why the 9704

• Large messages: up to 100,000 bytes each, against 340 bytes for an SBD uplink message.
• Two-way: devices can report, and also receive commands, settings and files.
• Global coverage: Iridium is a low-Earth-orbit system that reaches the sea, the poles and the mountains, as long as the sky is in view.
• Steady in bad weather: L-band is little affected by heavy rain, cloud and fog (see the 9704 compared with Starlink and OneWeb).
• Small and frugal: the module weighs 12 g, suiting battery-powered portable and unattended devices.

Mountain rescue and hiking safety

Many of Taiwan's high and remote mountains have no mobile signal, and what is most missing in an incident is information from the scene.

• What to send: position, photos of the injured and the scene, voice messages; the command centre can send instructions back.
• Why the 9704: a photo lets the command centre judge injuries and terrain and decide between a helicopter and a ground team, which coordinates and a few words cannot do. Mountains are often foggy and wet, and L-band stays steady.
• Design notes: high mountains can drop below 0°C in winter, so check the module version; valleys and tree canopy block the sky; keep battery in reserve for emergencies in portable devices.

Maritime

Fishing boats, yachts, research vessels and buoys lose mobile coverage not far from shore.

• What to send: position and track, deck or catch photos, engine and sensor logs, sea-state data; shore can send weather and instructions.
• Why the 9704: Iridium covers every ocean, including the poles; a whole period of logs goes in one message instead of dozens of SBD messages; buoys run on batteries or solar, and the module is frugal.
• Design notes: waterproofing and salt spray, antenna placement, signal while the vessel rolls.

Monitoring: forests, slopes, rivers and remote sites

• What to send: event-triggered photos or thermal images (people or animals, illegal logging, landslides), water levels and sensor logs, equipment status; the back end can ask for another shot or change settings.
• Why the 9704: beyond numbers you need evidence you can see, and a photo also cross-checks the sensor; typhoons and heavy rain are exactly when data matters most, and L-band still gets through.
• Design notes: send photos only when something happens and small messages otherwise, to save both battery and airtime.

Disaster response

Earthquakes, typhoons and floods often cut ground communications first. Field teams can send photos of the damage, voice reports and supply requests; the command centre can send tasks and map updates. Iridium does not depend on local ground infrastructure.

Agriculture and wildlife

Ranches and forest land usually have no signal. Send photos or thermal images of animals, irrigation and water-source status: small messages on a schedule, photos only when needed.

Where it does not fit

• Live video or video calls: a 100 KB message takes several minutes (see why IMT messages can take minutes); look at broadband services.
• Continuous high-volume data: satellite airtime becomes expensive.
• Only positions and a few readings: SBD is enough, and the 9603 and 9604 ecosystems are mature.