How it works

Phones, gateways, and radios — connected

A compatible gateway such as the CJ-1 sits between an existing radio system and Link’d phone users, relaying authorized live audio in both directions.

Existing radio users

CJ-1 or compatible gateway

Link’d phone users

Radio to phone

A radio user transmits on the configured DMR or analog system.
The supported gateway receives the RF call.
Link’d forwards the authorized live call to connected phone users.

Phone to radio

A phone user presses PTT.
Link’d delivers the live audio to the authorized gateway.
The gateway keys the selected radio channel or talkgroup and retransmits it.

Gateway support depends on the exact device, radio interface, licensing, configuration, and successful hardware validation.

Diagram: how Link’d DMR bridges phones and radios — a repeater or radio system connects through a MOTOTRBO ION or CJ-1 gateway running Link’d, which relays audio both ways between DMR radios and remote phone users on cellular or Wi-Fi — How Link’d DMR bridges phones and radios through a compatible gateway

ION gateway concept

Bridging MOTOTRBO ION and phones

A MOTOTRBO ION running Link’d is one gateway concept under validation: the ION receives DMR RF audio and relays it to Link’d phone users, and keys up to retransmit phone PTT audio back to the radio system. Without a gateway, phones still communicate over Link’d only.

Diagram: how Link’d DMR bridges MOTOTRBO ION and phones — MOTOTRBO radios and a repeater exchange DMR RF audio with a MOTOTRBO ION running Link’d, which acts as a two-way RF gateway sending radio traffic to regular phones with Link’d over cellular, Wi-Fi, or optional offline mesh — The ION acts as the two-way gateway between the RF radio system and Link’d users

Gateway support depends on the exact device, radio interface, licensing, configuration, and successful hardware validation. Link’d DMR is an independent project and is not affiliated with or endorsed by Motorola Solutions.

Offline mesh

Designed to keep working when coverage disappears

When internet service drops, nearby Link’d phones are designed to keep talking to each other over a local Wi-Fi mesh.

Regular Android phones use local Wi-Fi peer connections.
Nearby phones can forward traffic through multiple hops.
Additional powered field-relay devices can improve resilience.
A node that regains internet access may reconnect the local group to remote Link’d users.
A compatible CJ-1 may bridge the offline group into a radio system.

Estimated range

Early design estimates range from roughly 100–500 feet per ordinary phone-to-phone hop in open conditions. Dedicated relays and properly installed directional Wi-Fi bridges may extend coverage significantly. Actual results depend on terrain, device hardware, mounting, interference, and line of sight.

Link’d DMR offline mesh screen showing an active mesh network with nine connected nodes, primary and backup routes, hop count, route quality, and nearby link statistics — Offline mesh mode in the Link’d DMR app

Infographic: Link’d DMR offline coverage options — phone-to-phone mesh at roughly 100 to 500 feet per hop, vehicle or camp relays at 500 to 1,500 feet, basic directional bridges at 0.5 to 3 miles, elevated directional bridges at 3 to 10 miles, and large professional dishes at 10 to 20 or more miles; estimates only, actual range depends on terrain, obstacles, line of sight, phone hardware, antenna setup, and interference — Estimated offline coverage options by setup