kopia lustrzana https://github.com/M17-Project/M17_spec
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1.6 KiB
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40 wiersze
1.6 KiB
ReStructuredText
M17 RF Protocol: Summary
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M17 is an RF protocol that is:
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* Completely open: open specification, open source code, open source
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hardware, open algorithms. Anyone must be able to build an M17 radio
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and interoperate with other M17 radios without having to pay anyone
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else for the right to do so.
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* Optimized for amateur radio use.
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* Simple to understand and implement.
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* Capable of doing the things hams expect their digital protocols to
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do:
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* Voice (eg: DMR, D-Star, etc)
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* Point to point data (eg: Packet, D-Star, etc)
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* Broadcast telemetry (eg: APRS, etc)
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* Extensible, so more capabilities can be added over time.
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To do this, the M17 protocol is broken down into three protocol layers, like a network:
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#. Physical Layer: How to encode 1s and 0s into RF. Specifies RF
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modulation, symbol rates, bits per symbol, etc.
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#. Data Link Layer: How to packetize those 1s and 0s into usable
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data. Packet vs Stream modes, headers, addressing, etc.
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#. Application Layer: Accomplishing activities. Voice and data
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streams, control packets, beacons, etc.
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This document attempts to document these layers.
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.. [TETRA] Dunlop, John; Girma, Demessie; Irvine, James "Digital
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Mobile Communications and the TETRA System" Wiley 1999,
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ISBN: 9780471987925
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.. [DMR] ETSI TS 102 361-1 V2.2.1 (2013-02): "Electromagnetic
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compatibility and Radio spectrum Matters (ERM); Digital
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Mobile Radio (DMR) Systems; Part 1: DMR Air Interface (AI)
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protocol"
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https://www.etsi.org/deliver/etsi_ts/102300_102399/10236101/02.02.01_60/ts_10236101v020201p.pdf
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