Design and analysis of dynamically grouped multilevel space time trellis code

Abstract

The wireless communication systems are expected to support high speed multimedia services such as high speed internet access, mobile gaming, and high definition video transmission. The rapidly growing demand of these services is driving the communication technology towards reliable and high data rate transmission. In this research work, design and analysis of different dynamically grouped multilevel space-time trellis codes have been presented in order to support the rising demand for higher data rate and higher reliability in the wireless communication systems. The simulation results depict that the proposed codes provide better performance than existing multilevel space-time trellis codes (MLSTTCs) and grouped multilevel space-time trellis codes (GMLSTTCs). The proposed codes may be applied in the wireless communication systems such as GSM, CDMA, TDMA, and FDMA. MLSTTCs and GMLSTTCs consider channel state information (CSI) at the receiver only without considering the CSI at the transmitter. In this research work, effects of the CSI at the transmitter have been considered to improve the performance of MLSTTCs and GMLSTTCs. The CSI has been used to dynamically select a component space-time trellis code (STTC), adaptively group the transmit antennas, and provide a beamforming scheme for dynamic distribution of the transmit power across the transmit antennas. MLSTTCs and GMLSTTCs use predefined STTCs as the component codes in the multilevel coding. A code set selection algorithm has been proposed for dynamic selection of the generator sequences with the help of the CSI at the transmitter. The selected generator sequences are used to design dynamic space-time trellis codes (DSTTCs). The simulation results show that the coding gain of DSTTCs is superior to existing STTCs by 0.7 dB at frame error rate (FER) of 10-2. DSTTCs are used as the component code in multilevel coding for designing multilevel dynamic space-time trellis codes (MLDSTTCs) and grouped multilevel dynamic space-time trellis codes (GMLDSTTCs).