9th International Conference on Communications and Networking in China

Research Article

TTI Bundling Enhancements for Medium Data Rate PUSCH in LTE-Advanced Systems

  • @INPROCEEDINGS{10.4108/icst.chinacom.2014.256390,
        author={Shan Yang and Peng Chen and Xiaoming She and Yang Liu},
        title={TTI Bundling Enhancements for Medium Data Rate PUSCH in LTE-Advanced Systems},
        proceedings={9th International Conference on Communications and Networking in China},
        publisher={IEEE},
        proceedings_a={CHINACOM},
        year={2015},
        month={1},
        keywords={lte uplink tti bundling enhancements},
        doi={10.4108/icst.chinacom.2014.256390}
    }
    
  • Shan Yang
    Peng Chen
    Xiaoming She
    Yang Liu
    Year: 2015
    TTI Bundling Enhancements for Medium Data Rate PUSCH in LTE-Advanced Systems
    CHINACOM
    IEEE
    DOI: 10.4108/icst.chinacom.2014.256390
Shan Yang1,*, Peng Chen1, Xiaoming She1, Yang Liu1
  • 1: China Telecom
*Contact email: yangshan@ctbri.com.cn

Abstract

In order to improve network performance and cell-edge UE experience, a study item (SI) on LTE coverage enhancements has been proposed and approved for LTE-Advanced. In this SI, it was concluded that the coverage of medium data rate PUSCH (Physical uplink shared channel) is poorer than other LTE channels, with significant gap observed. Therefore, coverage improvement for medium data rate PUSCH is greatly desired for LTE operators. TTI bundling was first specified in LTE Release 8 to improve uplink coverage, especially for low rate data transmission. However, it cannot be applied to medium rate data transmission. In this paper, we propose an enhanced TTI (Transmission time interval) bundling scheme for medium data rate PUSCH. The proposed scheme can enable TTI bundling for PUSCH transmission with medium rate data, and achieve higher scheduling flexibility as well as larger turbo encoding gain. Link-level simulations validate that compared with PUSCH transmission without TTI bundling, TTI bundling enhancements can obtain 1.1-1.9 dB gain in terms of required SNR, and improve UE throughput by 24%-35%.