Traffic congestion of a random access (RA) link can be resolved by clustering machine type communication devices (MTCDs) and using an aggregator. However, since a packet needs to wait in the aggregator, clustering may cause an additional delay. To solve this problem, this letter suggests a partially clustered access scheme (PCAS) in which direct-access MTCDs (dMTCDs) and clustered-access MTCDs (cMTCDs) are serviced together. We provided an analytical model and an energy consumption model for PCAS. Numerical and simulation results showed that clustering may improve a success ratio. Furthermore, the delay requirement of dMTCDs and the energy consumption requirement of cMTCDs can be guaranteed by using PCAS.

中文翻译：

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海量机器类通信部分集群接入方案的性能评估

随机接入 (RA) 链路的流量拥塞可以通过对机器类型通信设备 (MTCD) 进行集群并使用聚合器来解决。然而，由于数据包需要在聚合器中等待，集群可能会导致额外的延迟。为了解决这个问题，这封信建议采用部分集群接入方案 (PCAS)，其中直接接入 MTCD (dMTCD) 和集群接入 MTCD (cMTCD) 一起提供服务。我们为 PCAS 提供了一个分析模型和一个能耗模型。数值和仿真结果表明聚类可以提高成功率。此外，dMTCDs 的延迟要求和 cMTCDs 的能耗要求可以通过使用 PCAS 来保证。