onehalfspacing in titlepage

How to make onehalfspacing in titlepage? I tried to add \onehalfspacing command in different places there, however, no spaces were produced.

\begin{titlepage}
{\fontsize{22}{22}\centering\bfseries\MakeUppercase{Lorem ipsum dolor sit amet,
\end{titlepage}

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You might want to add a paragraph break (\par) at the end of the group. Also the second number of \fontsize is the baselineskip, i.e. the line spacing, which is normally 20% larger than the font size (the first number). So use {\fontsize{22}{27}\centering ... \par}. The 27 should probably be even higher. I wouldn't recommend to use \fontsize at all, but \Huge and the setspace package. –  Martin Scharrer May 7 '12 at 13:10

Delete the brackets around your sentence:

\documentclass[pagesize]{scrartcl}

\usepackage{setspace}

\begin{document}
\begin{titlepage}
\onehalfspacing

\fontsize{22}{22}\centering\bfseries\MakeUppercase{Lorem ipsum dolor sit amet, consectetur adipisicing elit}
\end{titlepage}

\end{document}

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As stated above \fontsize{22}{22} isn't right and might interfere with setspace. The second number should be at least 20% higher. –  Martin Scharrer May 7 '12 at 13:10
@Keks Dose Thanks. It really works but I have another problem now. I want to write some not bolded text after this and \bfseries without brackets around makes not a good job. I cannot change it to \textbf because of \MakeUppercase. How should I solve this? –  Pavasaris May 7 '12 at 13:11
@myname: Try it with the braces but with a \par before }. –  Martin Scharrer May 7 '12 at 13:14
@Martin Scharrer: Thanks! Works fine. –  Pavasaris May 7 '12 at 13:17
@myname If possible and if it seems adequate to you, please hit the "answer accepted" button on the left side of my answer. –  Keks Dose May 7 '12 at 15:38