Title :
LTE Uplink Coverage Enhancement Techniques Based on Enhanced TTI Bundling
Author :
Yu Zhou ; Tiankui Zhang ; Zhimin Zeng ; Yiqun Li ; Yunan Han
Author_Institution :
Beijing Key Lab. of Network Syst. Archit. & Convergence, Beijing Univ. of Posts & Telecommun., Beijing, China
Abstract :
In the Long Term Evolution (LTE) system, there is limited on uplink average data rate the cell edge users for the power limitation and the inherent short Transmission Time Interval (TTI) length of the cell edge users. TTI bundling scheme was presented for the VoIP service in the LTE Release 8 specifications to solve the cell coverage problem. But the R8 TTI bundling is restricted to bundles of 4 TTIs, QPSK modulation and allocations up to 3 PRBs, which impose restrictions on the support of the medium data rate service. In this paper, several TTI bundling enhancement schemes with different RTT, HARQ process number, TTI bundled size and the maximum number of HARQ retransmission are discussed in detail and evaluated by the link-level simulation. The simulation analysis proves that TTI bundling enhancement schemes can effectively improve uplink coverage performance in LTE system.
Keywords :
Long Term Evolution; automatic repeat request; radio links; HARQ process number retransmission; LTE release 8 specification; LTE uplink coverage enhancement technique; Long Term Evolution; QPSK modulation; RTT; TTI bundling enhancement scheme; VoIP service; cell coverage problem; cell edge user; inherent short transmission time interval; link-level simulation; medium data rate service; power limitation; uplink average data rate; Data models; Delay; Long Term Evolution; Quality of service; Signal to noise ratio; Simulation; Uplink;
Conference_Titel :
Wireless Communications, Networking and Mobile Computing (WiCOM), 2012 8th International Conference on
Conference_Location :
Shanghai
Print_ISBN :
978-1-61284-684-2
DOI :
10.1109/WiCOM.2012.6478568
