2021/02/14 by Omur Ozel, Ozel, Omur, Parisa Rafiee +1
Computer Science · Medicine · Engineering · #Age of Information Optimization #Congenital Heart Disease Studies #IoT Networks and Protocols
paper · pdf · doi:10.48550/arxiv.2102.07075
Consider an energy harvesting node where generation of a status update\nmessage takes non-negligible time due to sensing, computing and analytics\noperations performed before making update transmissions. The node has to\nharmonize its (re)transmission strategy with the sensing/computing. We call\nthis general set of problems intermittent status updating. In this paper, we\nconsider intermittent status updating through non-preemptive sensing/computing\n(S/C) and transmission (Tx) operations, each costing a single energy recharge\nof the node, through an erasure channel with (a) perfect channel feedback and\n(b) no channel feedback. The S/C time for each update is independent with a\ngeneral distribution. The Tx queue has a single data buffer to save the latest\npacket generated after the S/C operation and a single transmitter where\ntransmission time is deterministic. Once energy is harvested, the node has to\ndecide whether to activate S/C to generate a new update or to (re)send the\nexisting update (if any) to the receiver. We prove that when feedback is\navailable average peak age of information (AoI) at the receiver is minimized by\na threshold-based policy that allows only young packets to be (re)sent or else\ngenerates a new update. We additionally propose window based and probabilistic\nretransmission schemes for both cases (a) and (b) and obtain closed form\naverage peak AoI expressions. Our numerical results show average peak AoI\nperformance comparisons and improvements.\n