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| {{ENG-CANSAT-NAV}} | | {{ENG-CANSAT-NAV}} |
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− | == Forewords ==
| + | {{COMMON-CANSAT-FREQUENCY-PLAN}} |
− | The RFM69 module and Packet Radio can do a lot to secure message transmission and message content (with the encryption key).
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− | As for wired network (aka TCP/IP) the packet radio enclose your data into datagram before sending it over the air. This helps the hardware to detect error and possibly recover when collisions occurs.
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− | Obviously, more we are talking on a same frequency, more we will have collision, less the communication will be efficient.
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− | The best solution would be to use a frequency plan where each team receives its own frequency range like showed in the following table.
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− | == Suggested Frequency Plan ==
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− | {| class="wikitable" border="1" | |
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− | | align="center" | '''Team'''
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− | | align="center" | '''Freq (MHz)'''
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− | | align="center" | '''Team name'''
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− | |- style="font-size: 90%"
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− | | align="left" | Team #1
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− | | align="left" | 433.1
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− | | align="left" | . .
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− | |- style="font-size: 90%"
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− | | align="left" | Team #2
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− | | align="left" | 433.2
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− | | align="left" |
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− | |- style="font-size: 90%"
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− | | align="left" | Team #3
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− | | align="left" | 433.3
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− | | align="left" |
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− | |- style="font-size: 90%"
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− | | align="left" | Team #4
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− | | align="left" | 433.4
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− | | align="left" |
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− | |- style="font-size: 90%"
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− | | align="left" | Team #5
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− | | align="left" | 433.5
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− | | align="left" |
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− | |- style="font-size: 90%"
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− | | align="left" | Team #6
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− | | align="left" | 433.6
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− | | align="left" |
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− | |- style="font-size: 90%"
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− | | align="left" | Team #7
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− | | align="left" | 433.7
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− | | align="left" |
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− | |- style="font-size: 90%"
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− | | align="left" | Team #8
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− | | align="left" | 433.8
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− | | align="left" |
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− | |- style="font-size: 90%"
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− | | align="left" | Team #9
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− | | align="left" | 433.9
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− | | align="left" |
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− | |- style="font-size: 90%"
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− | | align="left" | ...
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− | | align="left" | 434.0
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− | | align="left" | ...
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− | |}
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− | == Frequency plan explained ==
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− | Why do we space the frequencies of 0.1 MHz (so 100 KHz)? Spacing more (>100 KHz) will be best, spacing less (<100 KHz) is not recommended.
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− | The following capture coming from USA shows the spectrum view (and waterfall view) of a RFM69 emiting on the 868.0 MHz frequency.
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− | {{ambox|text=Note: the 868.0 Mhz is a FREE ISM band in USA. In Europe, that frequency range is reserved for LoRa transmission!}} | |
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− | [[Fichier:ENG-CANSAT-FREQUENCY-PLAN-10.png|640px]]<small><br />Source: [https://forum.mysensors.org/topic/11501/rfm69-range-issues this thread in the mysensors.org forum]</small>
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− | [[Fichier:ENG-CANSAT-FREQUENCY-PLAN-11.png]]<small><br />Source: [https://forum.mysensors.org/topic/11501/rfm69-range-issues this thread in the mysensors.org forum]</small>
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| {{ENG-CANSAT-TRAILER}} | | {{ENG-CANSAT-TRAILER}} |