Average Age of Information for Multi-Source Single Buffer Preemption Queueing Model with Packet Dropping in Service

Remote monitoring systems heavily rely on the Age of Information (AoI) as a critical metric to gauge the timeliness of status updates received by a destination. Presently, the predominant focus of AoI evaluations in sensor networks revolves around communication systems employing homogeneous preemption, often neglecting the issue of packet loss. Consequently, our research directs attention towards the single-buffer state update system featuring non-homogeneous preemption in scenarios involving packet dropping. This system entails a wireless communication network comprising three distinct components: a buffer, a server, and a destination node, each generated following the Poisson process and subsequently encapsulated into brief packets for transmission by the server. Initially, a diverse source buffer preemption strategy was employed, wherein packets of higher priority consistently superseded those of lower priority in the buffer, and packets originating from the same source were preempted in the buffer, resulting in the direct discarding of preempted packets. Subsequently, we compute the average Age of Information (AAoI) for diverse sources by leveraging Stochastic Hybrid System (SHS) methodologies to manage packet priorities. Ultimately, system simulations and numerical assessments unveil that with a 0.2 probability of detecting update packets, the AoI diminishes by 23.9% as the Signal-to-Noise Ratio (SNR) escalates from 30 dB to 60 dB. Holding the SNR constant at 60 dB while extending the packet length for status updates from 200 to 600 bits results in an average AoI reduction of 14.5%.