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Title: Minimizing Age of Information via Scheduling over Heterogeneous Channels
In this paper, we study the problem of minimizing the age of information when a source can transmit status updates over two heterogeneous channels. Our work is motivated by recent developments in 5G mmWave technology, where transmissions may occur over an unreliable but fast (e.g., mmWave) channel or a slow reliable (e.g., sub-6GHz) channel. The unreliable channel is modeled as a time-correlated Gilbert-Elliot channel, where information can be transmitted at a high rate when the channel is in the "ON" state. The reliable channel provides a deterministic but lower data rate. The scheduling strategy determines the channel to be used for transmission with the aim to minimize the time-average age of information (AoI). The optimal scheduling problem is formulated as a Markov Decision Process (MDP), which in our setting poses some significant challenges because e.g., supermodularity does not hold for part of the state space. We show that there exists a multi-dimensional threshold-based scheduling policy that is optimal for minimizing the age. A low-complexity bisection algorithm is further devised to compute the optimal thresholds. Numerical simulations are provided to compare different scheduling policies.  more » « less
Award ID(s):
1955535 1901218 1901057 2106932 1813050 2107363 2106993
NSF-PAR ID:
10284912
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Mobihoc
Page Range / eLocation ID:
111 to 120
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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