Tikzpicture of ILC schematic

ILC tikz.tex

\begin{figure}[h!]
\centering
\begin{tikzpicture}
\begin{tiny}
\bXInput{A}
\bXCompSum*{B}{A}{}{-}{}{}
\bXLink[$r\quad$]{A}{B}
\bXBloc[4]{C}{$C$}{B}
\bXLink[$e\qquad$]{B}{C}
\bXBranchy[-15]{B-C}{G}
\bXBloc{H}{L}{G}
\bXLinkyx{B-C}{H}
\bXCompSum*{D}{C}{}{}{}{}
\bXLink{C}{D}
\bXBloc{E}{$G$}{D}
\bXLink[$u$]{D}{E}
\bXOutput[4]{F}{E}
\bXLink[$y\qquad$]{E}{F}
\bXReturn{E-F}{B}{}
	\node [draw, circle,minimum size=1.5em,
		right of=H,node distance=4em,
		label=175:${}$,label=-85:${}$,
		label=85:${}$,bXStyleSum] (I) {};
	\node (Iright) at (I.south){};
	\node (Ileft) at (I.west){};

\bXLink{H}{I}
\bXBranchy[3.5]{I}{J}
\bXBloc[-1.5]{K}{$Q$}{J}
\bXBranchy[5.5]{K}{L}
\bXBloc[-2.45]{M}{\;Memory\;}{L}
\draw [bXLineStyle] (I)  --
 node[name=I-K,near end,right] {} (K);
\draw [bXLineStyle] (K)  --
 node[name=I-K,midway,left] {$f_{j+1}$} (M);
\bXLink[\hspace{-2em}$f_j$]{M}{D}
\node [right of=M-D, node distance=4em,
	minimum size=0em](returnM-D) {};
\draw [bXLineStyle] (M-D.west)--(returnM-D.west)
	|-   node[name=M-D-I,near end,right] {} (I);

\draw[draw=red,dashed] (0.75,0.5) rectangle ++(4.4,3.75) node[anchor=north east] {\small{ILC}};

\end{tiny}
\end{tikzpicture}
\label{fig:ILC_schematic}
\caption{Schematic of Frequency Domain ILC.}
\end{figure}