https://www.linuxtv.org/wiki/index.php?title=Modulation_Error_Ratio&feed=atom&action=historyModulation Error Ratio - Revision history2024-03-29T10:43:13ZRevision history for this page on the wikiMediaWiki 1.39.7https://www.linuxtv.org/wiki/index.php?title=Modulation_Error_Ratio&diff=33207&oldid=prevWirbel: Created page with "The '''Modulation Error Ratio''' describes the quality of an modulated digital signal, and gives a hint how fuzzy symbols in a constellation are. It is defined as the average po..."2014-03-11T15:28:14Z<p>Created page with "The '''Modulation Error Ratio''' describes the quality of an modulated digital signal, and gives a hint how fuzzy symbols in a constellation are. It is defined as the average po..."</p>
<p><b>New page</b></p><div>The '''Modulation Error Ratio''' describes the quality of an modulated digital signal,<br />
and gives a hint how fuzzy symbols in a constellation are.<br />
<br />
It is defined as the average power of symbols to the average power of the vector between<br />
ideal symbol position and real symbol position in constellation diagram:<br />
<br />
MER = Psym/Perr<br />
<br />
or, in logarithmic scale<br />
<br />
MER(dB) = 10 * log10(Psym/Perr) [dB]<br />
<br />
with<br />
<br />
Psym : average symbol power = sum(I.j^2 + Q.j^2) w. j = 1..N <br />
Perr : average error power = sum(dI.j^2 + dQ.j^2) w. j = 1..N<br />
<br />
The higher MER is, the better transmitted symbols can be recognized. If MER is too low, bit errors will happen.<br />
<br />
On the other hand, high MER values doesn't guarantee for good SNR values,<br />
if bursts or intermittent interference occur.<br />
<br />
<br />
<br />
<br />
TODO: formula as image.<br />
<br />
TODO: add image for symbol error vector in I/Q plane.<br />
<br />
[[Category:Technology]]</div>Wirbel