Digital Mobile Radio (DMR)

Digital Mobile Radio (DMR)

Frequencies	860 MHz,400 MHz,512 MHz,136 MHz,174 MHz,66 MHz,88 MHz
Frequency Range	66 MHz - 860 MHz
Mode	NFM
Modulation	4FSK
ACF	Frame: 60 ms, Slot: 30 ms
Emission Designator	—
Bandwidth	12.5 kHz
Location	Worldwide
Short Description	Digital Mobile Radio (DMR) is an open digital mobile radio standard defined by ETSI and used in commercial products around the world. Mostly used by private network and local police, can be encrypted. Used in MOTOTRBO products.
I/Q Raw Recording	Download file
Audio Sample

Digital Mobile Radio (DMR) is an open digital mobile radio standard defined in the European Telecommunications Standards Institute (ETSIEuropean Telecommunications Standards Institute. An independent, not-for-profit, standardization organization in the telecommunications industry in Europe, developing global telecommunications standards.) Standard TS 102 361 parts 1–4 and used in commercial products around the world. DMR, along with P25 and NXDN48 are the main competitor technologies in achieving 6.25 kHzKiloHertz (kHz) 10^3 Hz equivalent bandwidth using the proprietary AMBE+2 vocoder.

DMR and P25 Phase II both use two-slot TDMATime Division Multiple Access in a 12.5 kHzKiloHertz (kHz) 10^3 Hz channel, while NXDN48 uses discrete 6.25 kHzKiloHertz (kHz) 10^3 Hz channels using frequency division. DMR was designed with three tiers. DMR tiers I and II (conventional) were first published in 2005, and DMR tier III (trunked) was published in 2012, with manufacturers producing products within a few years of each publication. The primary goal of the standard is to specify a digital system with low complexity, low cost and interoperability across brands, so radio communications purchasers are not locked into a proprietary solution. In practice, many brands have not adhered to this open standard and have introduced proprietary features that make their product offerings non-interoperable.

Samples

Motorola Capacity Plus Control Channel:


Motorola Capacity Plus Rest Channel:




Hytera Extended Pseudo Trunk (XPT) Beacon:




Motorola Connect Plus Control Channel:




DMR Voice (Half Slot TDMATime Division Multiple Access):

Decoded Audio:

Decoding Software

Hobby Level Software

• Digital Speech Decoder (DSD).
• Recommended use of DSD+.
• DMRDecode For the precompiled binary: Download here
• SDRTrunk

Professional Software

• go2DECODE
• go2MONITOR
• Rohde&Schwarz CA100

Decoding Tutorials

• Following trunked radio with the RTL-SDR

Video Examples

• Greensboro, NC DMR repeater
• DSD decodor în DMR MOTOTRBO
• 12 minutes of DMR, MotoTrbo signal
• MOTOTRBO Digital Sound Sample
• Digital Voice Decoding with RTL SDR (RTL2832), DSD and SDR Sharp
• DMR Decode - Decoding Mototrbo Transmissions with DSD Digital Speech Decoder

Additional Links

• DMR vs dPMR
• WAVECOM Database: DMR
• shoc Database: DMR
• RadioReference.com DMR
• Wikipedia DMR
• Radioreference.com MOTOTRBO

Additional Images

Left: DMR Voice Channel. Right: DMR Trunking Channel. Each are 12.5 kHzKiloHertz (kHz) 10^3 Hz wide. Motorola Capacity Plus at 451.4875MHz heard in Halifax, Nova Scotia, Canada. The DMR system is "resting burst" then there is some voice or data transmission too. DMR Idle Burst every minute at 162.476 MHzMegaHertz (MHz) 10^6 Hz, Found in Nice, France on February 24th, 2018 IQQuadrature signals form the basis of complex RF signal modulation and demodulation, both in hardware and in software, as well as in complex signal analysis. File: File:Gqrx 20180224 175841 162476000.wav.zip Submitted by User Jsleroy Image of DMR TDMATime Division Multiple Access half slot Hytera XPT Beacon Burst