\chapter*{Abstract (Master Theses only)}
This is an abstract. It should be about half a page to a page in length.
It mostly serves as clarification for what to expect when reading the thesis:
What is your topic, what are the most striking results, what's the process of
getting these.
It is \emph{not} an introduction to the topic (that's what the introduction
chapter is for). Now, for a few lines of content:

Polar codes are the first codes to asymptotically achieve channel capacity with low complexity encoders and decoders.
They were first introduced by Erdal Arikan in 2009 \cite{polar:arikan09}.
Channel coding has always been a challenging task because it draws a lot of resources, especially in software implementations.
Software Radio is getting more prominent because it offers several advantages among which are higher flexibility and better maintainability.
Future radio systems are aimed at being run on virtualized servers instead of dedicated hardware in base stations \cite{cloudran:2015}.
Polar codes may be a promising candidate for future radio systems if they can be implemented efficiently in software.

In this thesis the theory behind polar codes and a polar code implementation in GNU Radio is presented.
This implementation is then evaluated regarding parameterization options and their impact on error correction performance.
The evaluation includes a comparison to state-of-the-art \ac{LDPC} codes.

\begin{figure}[h]
  \begin{subfigure}[t]{.49\textwidth}
    \begin{center}
      \def\dist{1.5}
      \def\power{3}
      \input{figures/polar_nbit_encoder_natural}
      \caption{8 bit polar encoder}
      \label{abs:polar_8bit_encoder_natural}
    \end{center}
  \end{subfigure}\,%
  \begin{subfigure}[t]{.49\textwidth}
    \begin{center}
      \def\dist{1.5}
      \def\power{3}
      \input{figures/polar_nbit_decoder}
      \caption{8 bit polar decoder}
      \label{abs:polar_8bit_decoder}
    \end{center}
  \end{subfigure}%
  \caption{Polar code encoding and decoding}
  \label{abs:encoder-decoder}
\end{figure}

The polar encoder is shown in Fig. \ref{abs:polar_8bit_encoder_natural}.

