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Title: Average Age of Information in Update Systems with Active Sources and Packet Delivery Errors
This paper studies the “age of information” (AoI) in a multi-source status update system where N active sources each send updates of their time-varying process to a monitor through a server with packet delivery errors. We analyze the average AoI for stationary randomized and round-robin scheduling policies. For both of these scheduling policies, we further analyze the effect of packet retransmission policies, i.e., retransmission without re- sampling, retransmission with resampling, or no retransmission, when errors occur. Expressions for the average AoI are derived for each case. It is shown that the round-robin schedule policy in conjunction with retransmission with resampling when errors occur achieves the lowest average AoI among the considered cases. For stationary randomized schedules with equiprobable source selection, it is further shown that the average AoI gap to round-robin schedules with the same packet management policy scales as O(N). Finally, for stationary randomized policies, the optimal source selection probabilities that minimize a weighted sum average AoI metric are derived.  more » « less
Award ID(s):
1836690
NSF-PAR ID:
10194249
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
IEEE wireless communications letters
Volume:
9
Issue:
8
ISSN:
2162-2337
Page Range / eLocation ID:
1164-1168
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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