Article in DSPDesignLine.com: M-QAM symbol error

Posted by Krishna Pillai

May 24, 2008

Its been a nice week for me, wherein I guest posted an article in DSPDesignLine.com.

The article derives the theoretical symbol error rate for M-QAM modulation. The theoretical results are further supplemented by Matlab/Octave simulation scripts.

Those who are familiar with derivation of symbol error rate for 16-QAM modulation will find the equations easy to interpret. As we did for 16-QAM,

(a) We identify the three different types of symbols - corner, inside, neither inside nor corner.

(b) Then we find the symbol error probability for each of the three types of symbols

Click here to read the article published in DSPDesignLine.com

The same article is cross-posted also in Embedded.com

For those who are not interested in the full article, the probability of error for M-QAM modulation is,

$P(e|MQAM) =2\left(1-\frac{1}{\sqrt{M}}\right)erfc\left(k\sqrt{\frac{E_s}{N_0}}\right)-\left(1-\frac{2}{\sqrt{M}}+\frac{1}{M}\right)erfc^2\left(k\sqrt{\frac{E_s}{N_0}}\right)$ .