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Title: Structural Properties of Optimal Transmission Policies for Delay-Sensitive Energy Harvesting Wireless Sensors
We consider an energy harvesting sensor transmit- ting latency-sensitive data over a fading channel. We aim to find the optimal transmission scheduling policy that minimizes the packet queuing delay given the available harvested energy. We formulate the problem as a Markov decision process (MDP) over a state-space spanned by the transmitter's buffer, battery, and channel states, and analyze the structural properties of the resulting optimal value function, which quantifies the long-run performance of the optimal scheduling policy. We show that the optimal value function (i) is non- decreasing and has increasing differences in the queue backlog; (ii) is non-increasing and has increasing differences in the battery state; and (iii) is submodular in the buffer and battery states. Our numerical results confirm these properties and demonstrate that the optimal scheduling policy outperforms a so-called greedy policy in terms of sensor outages, buffer overflows, energy efficiency, and queuing delay.  more » « less
Award ID(s):
1711335 2032033 2032387 1711592
PAR ID:
10060975
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
2018 IEEE International Conference on Communications (ICC)
Page Range / eLocation ID:
1 to 7
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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