Title :
Analysis of Conditional Error Rate and Combining Schemes in HARQ
Author :
Hang Long ; Wei Xiang ; Shanshan Shen ; Yueying Zhang ; Kan Zheng ; Wenbo Wang
Author_Institution :
Sch. of Electron. Eng., Beijing Univ. of Posts & Telecommun., Beijing, China
fDate :
5/1/2012 12:00:00 AM
Abstract :
In hybrid automatic repeat request (HARQ), maximum ratio combining (MRC) is usually employed at the receiver if the retransmission signal is the same as that in the first transmission. However, conventional performance analysis of HARQ and MRC does not consider that all previous transmissions fail. In this paper, we analyze the conditional error rate of HARQ with arbitrary combining schemes. Both the theoretical and approximate expressions of the conditional error rate are derived. Our analytical and simulation results reveal that conventional MRC is not optimum for HARQ, especially when the packet is short or the channel gain of the first transmission is much better than that of retransmission.
Keywords :
automatic repeat request; diversity reception; error analysis; HARQ; channel gain; conditional error rate; conditional error rate analysis; hybrid automatic repeat request; maximum ratio combining; retransmission signal; Approximation methods; Automatic repeat request; Bit error rate; Diversity reception; Receivers; Signal to noise ratio; Conditional error rate; hybrid automatic repeat request (HARQ); maximum ratio combining (MRC);
Journal_Title :
Signal Processing, IEEE Transactions on
DOI :
10.1109/TSP.2012.2184100
