Towards the implementation of advanced random access schemes for satellite IoT

Abstract

Summary Machine‐to‐machine (M2M) communications being pivotal for internet of things (IoT) networks are characterized by low‐cost, low complexity, and often energy constrained terminals with low traffic duty cycle. Satellite networks provide an attractive low‐cost solution for such application, in particular when the terminals (both fixed and mobile) are distributed over a wide geographical area not well served by terrestrial infrastructure. An ALOHA random access (RA) scheme is a natural candidate for M2M communications since it is well matched to sporadic traffic, and it requires little terminals coordination. However, the classical ALOHA scheme suffers from a low throughput when operated in a load region requiring low probability of packet loss. To overcome this intrinsic ALOHA limitation, in the last decade, a lot of effort has been devoted to the investigation of evolutions of the ALOHA scheme reducing the probability of destructive packet collisions thus making it more attractive for satellite IoT. In such context, the Contention Resolution Diversity ALOHA (CRDSA) scheme and the Asynchronous Contention Resolution Diversity ALOHA (ACRDA) have emerged as promising solutions thanks to their high spectral efficiency achievable with low packet loss probability. The results reported in literature are however assuming ideal demodulator performance. This paper investigates the design and optimization of RA burst demodulator algorithms for single‐frequency and multifrequency CRDSA and ACRDA. It evaluates the performance of such algorithms in a number of system scenarios of practical interest and studies the impact of relevant system parameters on several performance metrics.

Satellite Communications in the New Space Era: A Survey and Future Challenges

“…In case an acknowledgment (ACK) is not received from the network, the device goes to sleep and tries again to retransmit the same packet after a random time. Despite being a simple protocol and performing well at very modest traffic, the increased propagation delay in the satellite channel creates potential network stability issues, making it an unattractive solution for modern IoT satellite applications [232]. In the last decade, there has been an effort in investigating more advanced RA schemes for satellite IoT and a survey can be found in [233].…”

“…The above mentioned best-performing techniques adopt iterative successive interference cancellation to increase the detection probability of the received packets. The authors in [232] further investigate the performance of single-frequency and multifrequency CRDSA and ACRDA [238] under realistic parameters and for a number of system scenarios of practical interest. In [239] the phase noise impact on the performance of CRDSA is analyzed.…”

Energy and Rate Allocation for Massive Multiple Access With Interference Cancelation

“…We depict in Fig. 4 ASE (21) versus the traffic load α for a number of cases following the same structure in Section III.…”

“…Remarkably, both protocols have in common the adoption of IC schemes whose decoding performance is improved substantially under packet-power unbalance. They have been duly adopted in numerous settings due to their high performance and complexity-constrained operation [18]- [21]. Thus, the investigation of the best power unbalance required by the iterative receiver deserves special attention.…”