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dPMR or digital private mobile radio, is a Common Air Interface (CAI) for digital mobile communications. dPMR is an open, non-proprietary standard that was developed by the European Telecommunications Standards Institute (ETSI) and published under the reference ETSI TS 102 658. A simplified version of the dPMR protocol intended for licence-free applications was also published by ETSI under the reference TS 102 490. dPMR is very similar to NXDN protocol implementation by Kenwood and Icom; both now offer dual-standard equipment (July 2013). ==Specifications== *Access method: FDMA *Transmission rate: 4,800 bit/s *Modulation: four-level FSK What is significant is that dPMR achieves all this in a 6.25 kHz channel. Because the emission mask is so tight, two 6.25 kHz dPMR signals can be used next to each other within a 12.5 kHz channel without causing interference to each other or adjacent channels. Compliance with EN301 166 at 6.25 kHz for current equipment is one measure of guarantee that interference issues are no different from at 12.5 kHz or 25 kHz. Frequency co-coordinators in the USA have even made recommendations to the FCC about setting up new 6.25 kHz systems adjacent to existing systems, outlining parameters to avoid harmful interference. dPMR equipment complies with the relevant European standard ETSI EN 301 166 as well as the FCC emission mask applicable for operation in the US. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「digital private mobile radio」の詳細全文を読む スポンサード リンク
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