\begin{center}
\vspace{2ex}
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\textref h:C v:C
\htext (1.80 -1.80){}
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%begin textrectangle
\textref h:C v:C
\htext (3.2 -0.10){$P_{j,t}\; (t=2,3,\ldots,l),\; l\triangleq m-j+1,\; j=1,2,\ldots,k,\; i=j+t-1.$}
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\htext (0.80 -0.76){$c_{j,i}$}
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\htext (1.80 -0.77){$s_{j,i}$}
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\htext (1.04 -1.04){$\ddots$}
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\htext (2.43 -2.39){$\ddots$}
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\htext (1.30 -2.31){$\Large \boldsymbol{0}$}
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\htext (2.32 -1.29){$\Large \boldsymbol{0}$}
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\htext (3.34 -1.80){$\gets$}
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\htext (4.76 -1.805){$\begin{myframe}{5.6cm} 
$r_{j,1}:=y_{1,j}$\\[1.35ex]
Äëÿ $t=2,\ldots,l$ \\[1ex]
\quad $r_{j,t}:=\sqrt{r_{j,t-1}^2 + y_{t,j}^2 }$\\[1.9ex]
\quad $c_{j,j+t-1}:=\frac{\displaystyle r_{j,t-1}}{\displaystyle r_{j,t}}$ \\[2ex]
\quad $s_{j,j+t-1}:=\frac{\displaystyle y_{t,j}}{\displaystyle r_{j,t}}$ \\[1ex]
$r_j\triangleq r_{j,l}= \sum\limits_{t=1}^{l}y_{t,j}^2=\Vert y_j \Vert^2$
\end{myframe}$}
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\htext (6.15 -1.80){$\gets$}
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\textref h:C v:C
\htext (6.60 -1.80){}
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\htext (6.61 -0.10){${\displaystyle y_j}\atop{\displaystyle\Downarrow}$}
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\htext (6.61 -0.77){$y_{1,j}$}
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\end{center}