Synchronous H-ARQ with energy reduction (ER-HARQ) retransmissions

An H-ARQ scheme with energy reduction transmission for the retransmitted subpackets termed energy reduction H-ARQ (ER-HARQ) is proposed and adopted in the Revision D of cdma2000. Compared to the conventional H-ARQ, ER-HARQ offers higher H-ARQ gain and less transmission time. In this paper we describe the ER-HARQ and show the performance gain by simulation with respect to the average number of subpacket transmissions and required Eb/Nt to achieve a given target performance.