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Ligne 79 : |
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| − | == The game of minimum lost ==
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| − | When doing radio transmission, your devices tries to emit data over the air with electricity.
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| − | {{dbox-orange| As you can easily figure out, the air is a very poor electric conductor! That results a significant portion of the power is lost in the air. }}
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| − | '''The power lost is expressed in dBm''' (see [https://en.wikipedia.org/wiki/DBm dBm on wikipedia]).
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| − | dBm provides a relatively intuitive way to express the power level/power lost of a signal.
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| − | [[Fichier:COMMON-CANSAT-ANTENNA-minimum-lost.png]]
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| − | {{dbox-orange| Power Lost also occurs in the antenna, the coaxial cable and the RF connector! }}
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| − | Wrong material or poor antenna design can result is a power lost bigger than air transmission!
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| − | The good new is that power can also be gain with a good antenna design (this usually requires some tuning).
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| | == Antenna connector == | | == Antenna connector == |