Energy Harvesting Powered Sensing in IoT: Timeliness Versus Distortion

12/28/2019
by   Yunquan Dong, et al.
0

We consider an Internet-of-Things (IoT) system in which an energy harvesting powered sensor node monitors the phenomenon of interest and transmits its observations to a remote monitor over a Gaussian channel. We measure the timeliness of the signals recovered by the monitor using age of information (AoI), which could be reduced by transmitting more observations to the monitor. We evaluate the corresponding distortion with the mean-squared error (MSE) metric, which would be reduced if a larger transmit power and a larger source coding rate were used. Since the energy harvested by the sensor node is random and limited, however, the timeliness and the distortion of the received signals cannot be optimized at the same time. Thus, we shall investigate the timeliness-distortion trade-off of the system by minimizing the average weighted-sum AoI and distortion over all possible transmit powers and transmission intervals. First, we explicitly present the optimal transmit powers for the performance limit achieving save-and-transmit policy and the easy-implementing fixed power transmission policy. Second, we propose a backward water-filling based offline power allocation algorithm and a genetic based offline algorithm to jointly optimize the transmission interval and transmit power. Third, we formulate the online power control as an Markov Decision Process (MDP) and solve the problem with an iterative algorithm, which closely approach the trade-off limit of the system. Also, we show that the optimal transmit power is a monotonic and bi-valued function of current AoI and distortion. Finally, we present our results via numerical simulations and extend results on the save-and-transmit policy to fading sensing systems.

READ FULL TEXT

page 1

page 9

research
08/13/2021

Sleep, Sense or Transmit: Energy-Age Tradeoff for Status Update with Two-Thresholds Optimal Policy

Age-of-Information (AoI), or simply age, which measures the data freshne...
research
02/25/2019

Optimal Online Transmission Policy for Energy-Constrained Wireless-Powered Communication Networks

This work considers the design of online transmission policy in a wirele...
research
10/15/2020

Minimization of Age-of-Information in Remote Sensing with Energy Harvesting

In this paper, minimization of time-averaged age-of-information (AoI) in...
research
01/26/2019

Optimal Online Transmission Policy in Wireless Powered Networks with Urgency-aware Age of Information

This paper investigates the age of information (AoI) for a radio frequen...
research
01/27/2020

Distributed Sensing with Orthogonal Multiple Access: To code or not to Code?

We consider the estimation distortion of a distributed sensing system wi...
research
04/06/2019

Weighted-Sum Average Age of Information in Unilaterally Powered Two-Way Data Exchanging Systems

This paper considers a two-way data exchanging system with a constant po...
research
05/05/2023

Joint Design of Sampler and Compressor for Timely Status Updates: Age-Distortion Tradeoff

We consider a joint sampling and compression system for timely status up...

Please sign up or login with your details

Forgot password? Click here to reset