# Ma wcnc 2018 slides

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Outline • Introduction

• Nonlinear superposition • New problem in wireless charging

• Algorithm design

• Related works • Weight-Greedy Picking

• Experiments • Conclusion and future works

Nonlinear Superposition • Radio interference occurs • Two chargers may strengthen or weaken each other

Nonlinear superposition • Charging model • !"# = '(*

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The difference between these two charging model

Our problem in wireless charging • Variable: scheme chargers on/off state in every charging period. • Objective: minimize charging periods. • Constraint: charge each sensor with energy no less than E.

Related work • Computation ahead Have to calculate the charging utility of each charger set at every sensor node in advance. As a result, the complexity of this step grows exponentially with the number of chargers, making it much more complex than previously thought.

Weight-Greedy Picking First find a MCS: pick charger with the maximum weight, and the remove chargers and repeat; Add new chargers: add the charger which has the most effective

A simple Example S1

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An example of a MCS

Experiments

Conclusion and Future Work • Nonlinear superposition • Adjustable initial phases • Different duration of each charging period

! [email protected]