Home / Problems We Solve / No network in the field
CommunicationsHow to communicate where there is no mobile network
Remote terrain, border areas and disaster zones often have no coverage at all.
How can a team communicate with no signal?
The places where teams most need to reach each other are often the places phones do not work. Without coverage, a team can split up and lose contact completely.
Mobile phones depend on towers. In remote terrain, border areas or after a disaster, there may be none in reach, and a team that spreads out can lose contact.
A mesh device works differently. Each unit links directly to the others and passes messages along, so the group does not need a SIM, a tower or internet.
Signs you have this problem
- Your teams regularly work beyond mobile coverage
- Groups lose contact once they separate
- Disasters or remote work leave you without a backup channel
- Your messages should not depend on a public network
What to look for
- No SIM, tower or internet requirement
- Mesh networking between units
- Encrypted messages by default
- A simple way to send messages from a phone
The main causes
Remote terrain
Mountains, forests and borders are beyond mobile coverage.
Failed networks
Disasters can take towers and power offline.
Exposed channels
Public networks are not suited to sensitive messages.
Before and after
How to solve it, step by step
- 1
Carry
Each team member carries a Sandesh device.
- 2
Link
Devices join an encrypted mesh with each other.
- 3
Pair
Connect a phone through the Sandesh app.
- 4
Message
Messages pass between units with no network.
Common questions
What is a mesh communication device?
It is a device that connects directly to other nearby units. Messages can hop between them, so the group covers more ground than one unit alone.
Does Sandesh need a SIM card?
No. Sandesh devices talk to each other with no SIM, tower or internet connection.
What is the range of Sandesh?
We are finalising the published specification sheet. Contact us and the engineering team will share current figures for your use case.
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Tell us about your mission and our engineers will suggest the right platform or configuration.