Research Article
Backoff HARQ for Contention-Based Transmission in 5G Uplink
@INPROCEEDINGS{10.1007/978-3-030-14657-3_28, author={Xun Li and Zhangdui Zhong and Yong Niu and Hong Zhou}, title={Backoff HARQ for Contention-Based Transmission in 5G Uplink}, proceedings={IoT as a Service. 4th EAI International Conference, IoTaaS 2018, Xi’an, China, November 17--18, 2018, Proceedings}, proceedings_a={IOTAAS}, year={2019}, month={3}, keywords={Internet of Things (IoT) Fifth generation (5G) Contention-based access HARQ Back off}, doi={10.1007/978-3-030-14657-3_28} }- Xun Li
Zhangdui Zhong
Yong Niu
Hong Zhou
Year: 2019
Backoff HARQ for Contention-Based Transmission in 5G Uplink
IOTAAS
Springer
DOI: 10.1007/978-3-030-14657-3_28
Abstract
With extraordinary growth in the Internet of Things (IoT), the amount of data exchanged between IoT devices is growing at an unprecedented scale, which is an important requirement for Fifth generation (5G) networks. Current Long Term Evolution (LTE) system is not able to efficiently support massive connectivity, especially on the uplink (UL). The contention based transmission enables to transmit data packet without waiting for dynamic and explicit scheduling grant from base station, and is more efficient for small packet transmission in terms of lower signaling overhead, lower latency and lower energy consumption. However, this may lead to high collision rates and a large amount of retransmissions. New low complexity recovery mechanism of non-successful transmissions is needed. So in this paper, a new Hybrid Automatic Repeat reQuest (HARQ) mode, called Backoff HARQ, is proposed for contention-based (CB) transmission in 5G uplink. For Backoff HARQ mode, round trip time (RTT) is set to a longer random time. We can get more HARQ processes and put off the retransmission information for the longer random backoff time as we set. We evaluate the proposed backoff HARQ mode using system simulations and show that the new mode provides superior system performance.