Research On The Adaptive Coded Modulation Based On HARQ And CT-TCM

Adaptive coded modulation is a powerful technique for improving the energy efficiency and increasing the data rate in the wide wireless network. This thesis, therefore, combines the recently proposed technique of CT-TCM with HARQ, and designs a new scheme of adaptive coded modulation. By theory analyzing and computer simulation, the results show that this system has higher spectrum efficiency and lower complexity.The following aspects are investigated in this thesis.1. The background and research situation of TCM codes are presented and the current research results are introduced in the first part of the thesis. And efficient constructing methods on CT-TCM codes are systemically interpreted later. Its translation algorithm is also introduced. Then, we present the performance of CT-TCM on different channel and analyze their complexity.2. We introduce the type of HARQ. III type of HARQ was analyzed in detail, including some relevant techniques, such as retransmission, code combination. By using the methods of theory and computer simulation, we combine III type of HARQ and CT-TCM together to complete the adaptation. Many useful results were gained and we then evaluate efficiency of the schemes.3. We introduce many methods of adaptation and present several typical fading channel models. The fixed threshold shifting was divided according to different coding and modulation ways in different channel. The average signal-to-noise rate (SNR) has changed some adiustments. By this ways, spectral efficiency can be increased and at the same time to arrive the throughout limit of each coding modulation way.