If you need to create a diagram but you don’t have a powerful tool like Visio (cause it’s expensive n it’s for windows :p ), or you have the tool but not comfortable with it (like ADA, well in my case 
), you might want to try Gliffy Online. Through that website, you can create a very nice diagram easily (well again, for me it’s easy to use). And just like Visio and ADA, you can create any type of diagram like UML, network, flow chart, etc. After done creating your diagram, you can save it as jpeg or png. Or you can just publish it like this one.
First taste of Gliffy Online
Morning Coffee
) to do it everytime. But using this addon, I can add them to my everyday morning coffee, so that everytime I want to open them I just need to click once, and they all will be opened in tabs. 便利ですね。。。
So I tried to solve it myself, but I’m stuck. So I posted here my unfinished work, maybe you can help me figuring it out.
. 
is the instantaneous SNR on the 
th channel.
, 
and
(average SNR per channel). So the characteristic function is
.![\int x^ne^{ax}dx=\frac{e^{ax}}{a^{n+1}}\left[ (ax)^n-n(ax)^{n-1}+n(n-1)(ax)^{n-2}-\dots+(-1)^nn!\right]](http://s0.wp.com/latex.php?latex=%5Cint+x%5Ene%5E%7Bax%7Ddx%3D%5Cfrac%7Be%5E%7Bax%7D%7D%7Ba%5E%7Bn%2B1%7D%7D%5Cleft%5B+%28ax%29%5En-n%28ax%29%5E%7Bn-1%7D%2Bn%28n-1%29%28ax%29%5E%7Bn-2%7D-%5Cdots%2B%28-1%29%5Enn%21%5Cright%5D+&bg=161410&fg=999999&s=0 "\int x^ne^{ax}dx=\frac{e^{ax}}{a^{n+1}}\left[ (ax)^n-n(ax)^{n-1}+n(n-1)(ax)^{n-2}-\dots+(-1)^nn!\right]")
![\left.(K-1)(K-2)\left(-\frac{\gamma_b}{\bar \gamma_c} \right)^{K-3}-\dots+(-1)^{K-1}(K-1)!\right]](http://s0.wp.com/latex.php?latex=%5Cleft.%28K-1%29%28K-2%29%5Cleft%28-%5Cfrac%7B%5Cgamma_b%7D%7B%5Cbar+%5Cgamma_c%7D+%5Cright%29%5E%7BK-3%7D-%5Cdots%2B%28-1%29%5E%7BK-1%7D%28K-1%29%21%5Cright%5D+&bg=161410&fg=999999&s=0 "\left.(K-1)(K-2)\left(-\frac{\gamma_b}{\bar \gamma_c} \right)^{K-3}-\dots+(-1)^{K-1}(K-1)!\right]")
also
![\left.+(K-1)(K-2)\left(-\frac{\gamma_b}{\bar \gamma_c} \right)^{K-3}-\dots+(-1)^{K-1}(K-1)!\right]d\gamma_b](http://s0.wp.com/latex.php?latex=%5Cleft.%2B%28K-1%29%28K-2%29%5Cleft%28-%5Cfrac%7B%5Cgamma_b%7D%7B%5Cbar+%5Cgamma_c%7D+%5Cright%29%5E%7BK-3%7D-%5Cdots%2B%28-1%29%5E%7BK-1%7D%28K-1%29%21%5Cright%5Dd%5Cgamma_b+&bg=161410&fg=999999&s=0 "\left.+(K-1)(K-2)\left(-\frac{\gamma_b}{\bar \gamma_c} \right)^{K-3}-\dots+(-1)^{K-1}(K-1)!\right]d\gamma_b")
![P_2=\left[ \frac{1}{2}(1-\mu)\right]^K\sum_{k=0}^K \binom{K-1+k}{k}\left[ \frac{1}{2}(1+\mu)\right]^k](http://s0.wp.com/latex.php?latex=P_2%3D%5Cleft%5B+%5Cfrac%7B1%7D%7B2%7D%281-%5Cmu%29%5Cright%5D%5EK%5Csum_%7Bk%3D0%7D%5EK+%5Cbinom%7BK-1%2Bk%7D%7Bk%7D%5Cleft%5B+%5Cfrac%7B1%7D%7B2%7D%281%2B%5Cmu%29%5Cright%5D%5Ek&bg=161410&fg=999999&s=0 "P_2=\left[ \frac{1}{2}(1-\mu)\right]^K\sum_{k=0}^K \binom{K-1+k}{k}\left[ \frac{1}{2}(1+\mu)\right]^k")
