\documentclass{scrartcl}
\usepackage{color}
\usepackage{multicol}
\usepackage[final]{graphicx}
\usepackage{pst-plot,pstricks}
\begin{document}
	\psset{xunit=1cm,yunit=1cm}
	\begin{pspicture}(-4,-0.5)(4,3)
		\psline(-3,0)(-3,1)
		\psline(-3,1)(-1,1)
		\psline(-1,1)(-1,2)
		\psline(-1,2)(1,2)
		\psline(1,2)(1,1)
		\psline(1,1)(3,1)
		\psline(3,1)(3,0)
		\psframe[linecolor=green,linestyle=dotted](-3,0)(1,1)
		\psframe[linecolor=blue,linestyle=dotted](-1,0)(3,1)
		\psaxes[Dx=5,Dy=5]{->}(0,0)(-4,-0.5)(4,3)
		\rput[l](3.7,0.2){$t$}
		\rput[r](0,3){$g\left(t\right)$}
		\rput(-3,-0.2){$-3T$}
		\rput(3,-0.2){$3T$}
	\end{pspicture}
\end{document}
