Preprocessing of TTI Bundling for Adaptive Transmission in LTE Uplink
YANG Fan;LI Yang;TAN Jia-jia;SHAO Huai-zong;School of Communication and Information Engineering,University of Electronic Science and Technology of China;
In order to improve the cell coverage performance, transmission time interval(TTI) bundling technique is employed in long term evolution(LTE) uplink for the voice over internet protocol(VoIP) service. Recently, a coverage-enhanced scheme makes user equipment(UE) transmitting up to five bundles under the same delay budget. However, the coverage-enhanced scheme lacks time for feedback processing, in which the UE transmitting power may be wasted for an unnecessary retransmission. Taking the issue into account, we propose a scheme based on preprocessing of TTI bundling for adaptive transmission in LTE uplink. Our scheme uses block error rate(BLER) versus signal-to-noise ratio(SNR) mapping mechanism to reduce unnecessary retransmission bundles and save UE power consumption, yielding higher throughput.