Receiver memory management method for HARQ in LTE‐based satellite communication system

Summary For the successful deployment of the long term evolution (LTE)‐based mobile satellite service, the price of a user terminal is one of the major factors. A user terminal for the LTE‐based satellite communication needs to be implemented with a similar hardware size that is used for a terrestrial LTE user terminal. However, for quality of service provision, the satellite user terminal needs a larger size of memories than the terrestrial terminal does. This is very evident by considering that the N ‐channel stop and wait hybrid automatic repeat request requires proportionally increasing memory size by the propagation delay, resulting in unmanageable amount of memories in the satellite system. To resolve this problem, we propose an efficient memory management method at the user terminal when the size of memory is insufficient. The simulation results in this paper reveal that the proposed method can increase the throughput about 20.7% when a user terminal is operated under very low throughput condition with an insufficient memory size, compared with the case without memory management scheme. In addition, we show that the additional throughput gain can be obtained by the packet scheduling using the information of receiver memory status. Copyright © 2015 John Wiley & Sons, Ltd.