AG Kommunikationstheorie
Thema:
Channel Quality Feedback Strategies for LTE NetworksAbstract:
In LTE systems, user terminal (UE) measures the link quality both in time and frequency domain, maps the Channel State Information (CSI) into Channel Quality Indicator (CQI), and then reports the derived CQI to eNodeB. With the reported CQI, eNodeB can apply Adaptive Modulation and Coding (AMC) for the next downlink transmission. Thus, to improve the transmission quality, CQI shall be derived correctly according to varying channel state. In this report, the CQI mapping scheme is investigated both for AWGN channel and more complex fading channel with interference. The CQI feedback is also enhanced to compensate the CQI feedback delay by introducing prediction technology. A novel CQI feedback model with robust SINR prediction is proposed and compared with conventional CQI feedback delay compensation schemes in fading channel with interference.