On the construction of capacity achieving full diversity space-time block codes

We propose a new class of space-time block codes that provide full spatial diversity and preserve the mutual information of the original channel. The remaining degrees of freedom may be exploited to optimize the codes with respect to other criteria like the distance profile after the channel. The constructed codes are based on a layered transmission where each layer is encoded by an orthogonal space-time block code. A real-valued transmission model is used to compare the new codes with known space-time block codes like, for example, linear dispersion codes or multi-stratum space-time codes. This model includes many different space-time codes. Encoding and decoding is always carried out by applying a single spreading matrix at the transmitter and the receiver, respectively. Due to the simplicity of the model, well known code properties may be easily deduced and new design criteria become obvious.