\documentclass[a4paper,12pt]{report} 
\usepackage{amsmath}
\usepackage{arydshln}
\usepackage{tikz}
\usepackage{xepersian}
\settextfont[Scale=.6]{XB Zar}

\begin{document}

\begin{tikzpicture}[scale=.6]
\draw [,stealth-stealth,dotted] (-1.2,2) -- (2,2)node[midway,sloped,above]{${\cal N}$};
\node at (-0.5,1.4) {${\cal S}_1$};
\node at (1.5,1.4) {${\cal S}_2$};
\node at (0,0)
{$H=
\left[
    \begin{array}{ccc;{2pt/2pt}ccc}
      &&&&&\\
      &&&&&\\
      &  H_1 &&& H_2 &\\
       &&&&&\\
      &&&&&\\
    \end{array}
\right]
$};
\draw [,stealth-stealth,dotted] (2.5,1.3) -- (2.5,-1.2)node[midway,right]{${\cal L}=\frac{\cal N}{2}$};

\end{tikzpicture}
\end{document}