Field Guide · protocol

Also known as: DMR Tier I, DMR Tier 1

DMR Tier I is the licence-free tier of the DMR standard, defined by ETSI for low-power, short-range consumer and light commercial use without an individual user licence.1

fixed low-power channel licence-free, no trunking
DMR Tier I uses fixed, low-power licence-free channels with no system planning or trunking.

Overview

Tier I targets the same role as licence-free analog radios, but digital. It uses fixed low power and a small set of designated channels, so no system planning or trunking is involved. Equipment is simple and inexpensive.

Technical characteristics

Property Value
Licensing Licence-free, limited power
Access Conventional (TDMA-capable hardware)
Channel 12.5 kHz
Modulation 4FSK
Vocoder AMBE+2

History

Tier I was specified alongside the other tiers in ETSI’s DMR documents to cover the unlicensed consumer segment.1

Deployment

Found in inexpensive consumer handhelds in regions that allocate licence-free DMR channels; less common than Tier II in North America.

Decoding it with GopherTrunk

Tier I traffic is conventional DMR and decodes like any Tier II conventional channel once tuned. See Status.

Sources

  1. Digital mobile radio — Wikipedia, for the ETSI DMR tier structure, including the licence-free Tier I.  2

See also