TY - JOUR
T1 - Deep-Reinforcement-Learning-Based NOMA-Aided Slotted ALOHA for LEO Satellite IoT Networks
AU - Yu, Hanxiao
AU - Zhao, Hanyu
AU - Fei, Zesong
AU - Wang, Jing
AU - Chen, Zhiming
AU - Gong, Yuping
N1 - Publisher Copyright:
© 2014 IEEE.
PY - 2023/10/15
Y1 - 2023/10/15
N2 - The low earth orbit (LEO) satellites have received extensive attention as an essential supplement to the terrestrial network for supporting global Internet of Things (IoT) services. Considering the rapid growth of IoT devices and the significant satellite-to-ground latency, proposing low-latency, low-overhead access protocols for LEO satellite IoT systems is challenging. In this article, we propose a multibeam random access (RA) framework and deploy the deep reinforcement learning (DRL) algorithm to control the nonorthogonal multiple access (NOMA) aided RA strategy. First, we divide the satellite coverage region into multiple beams and assume that the adjacent beams share parts of regions. Hence, the devices in the sharing region are allowed to transmit packets in two periods allocated for the two beams. Then, packets in multiple beams can be decoded jointly by an interslot successive interference cancelation (SIC) decoder. In addition, we consider the heterogeneity among devices and assign different power levels for heterogeneous types of devices, which enables power-domain NOMA and the intraslot SIC decoder in this system to mitigate the collision resolution. To maximize the average throughput, the deep deterministic policy gradient (DDPG) algorithm is adopted to achieve an online decision to optimize the RA protocol where the packet repetition strategies of devices are adjusted dynamically. The simulation results show that the proposed scheme outperforms the traditional benchmark schemes with significant throughput gain.
AB - The low earth orbit (LEO) satellites have received extensive attention as an essential supplement to the terrestrial network for supporting global Internet of Things (IoT) services. Considering the rapid growth of IoT devices and the significant satellite-to-ground latency, proposing low-latency, low-overhead access protocols for LEO satellite IoT systems is challenging. In this article, we propose a multibeam random access (RA) framework and deploy the deep reinforcement learning (DRL) algorithm to control the nonorthogonal multiple access (NOMA) aided RA strategy. First, we divide the satellite coverage region into multiple beams and assume that the adjacent beams share parts of regions. Hence, the devices in the sharing region are allowed to transmit packets in two periods allocated for the two beams. Then, packets in multiple beams can be decoded jointly by an interslot successive interference cancelation (SIC) decoder. In addition, we consider the heterogeneity among devices and assign different power levels for heterogeneous types of devices, which enables power-domain NOMA and the intraslot SIC decoder in this system to mitigate the collision resolution. To maximize the average throughput, the deep deterministic policy gradient (DDPG) algorithm is adopted to achieve an online decision to optimize the RA protocol where the packet repetition strategies of devices are adjusted dynamically. The simulation results show that the proposed scheme outperforms the traditional benchmark schemes with significant throughput gain.
KW - Deep deterministic policy gradient (DDPG)
KW - low earth orbit (LEO) satellite networks
KW - nonorthogonal multiple access (NOMA)
KW - random access (RA)
KW - slotted ALOHA (SA)
UR - http://www.scopus.com/inward/record.url?scp=85161042229&partnerID=8YFLogxK
U2 - 10.1109/JIOT.2023.3277836
DO - 10.1109/JIOT.2023.3277836
M3 - Article
AN - SCOPUS:85161042229
SN - 2327-4662
VL - 10
SP - 17772
EP - 17784
JO - IEEE Internet of Things Journal
JF - IEEE Internet of Things Journal
IS - 20
ER -