DMR
• Similar data throughput P25 Phase 2
– 9600 bps (symbol rate of 4800 symbols/sec)
– 2-slot TDMA
• 4FSK Modulation
– No need for linear transmitters
› Cost and size about same as analog FM transmitter
• Transmitter output spectrum fits into existing 12.5 kHz narrowband FM Analog channel
– No need for re-banding or re-licensing
– Thus can choose best frequency for application
• Designed to make analog to digital upgrade easy
• Coverage designed to be the same as Analog FM
– Can use existing Infrastructure sites
Advantages of DMR
• Non-proprietary open standard
• Commercially attractive alternative to P25 for those who do not need a high-end system
• Gives 6.25 kHz channel efficiency, four times that of legacy 25 kHz Analog channels, which complies with all current and likely future FCC mandates.
• Doubles network call capacity when replacing an analog network with 12.5 kHz bandwidth
• TDMA extends radio battery charge duration, when compared with P25 or 12.5 kHz analog FM radios
• 12.5 kHz channel size allows re-use of existing frequency licenses and site infrastructure (i.e., combiners, antennas)
Disadvantages of DMR
Does not provide full duplex
