High-Efficiency Resonant Beam Charging and Communication

TL;DR

This work addresses powering and communicating IoT devices via simultaneous wireless information and power transfer (SWIPT) using a resonant beam system with a semiconductor gain medium and a telescope internal modulator (TIM). An analytical end-to-end model is developed to capture beam propagation, energy conversion, and data transmission, enabling evaluation of $P_E^{out}$, $\eta_E$, and $\tilde{C}$. Numerical results show $P_E^{out}$ up to about $16$ W, $\eta_E$ around $0.11$, and $\tilde{C}$ up to about $18$ bit/s/Hz over practical distances (≈10 m), representing a substantial efficiency and spectral performance improvement over prior RB schemes. These findings indicate RB-SWIPT with semiconductor gain and TIM can support high-power, high-rate wireless charging and communication for IoT and UAV applications.

Abstract

With the development of Internet of Things (IoT), demands of power and data for IoT devices increase drastically. In order to resolve the supply-demand contradiction, simultaneous wireless information and power transfer (SWIPT) has been envisioned as an enabling technology by providing high-power energy transfer and high-rate data delivering concurrently. In this paper, we introduce a high-efficiency resonant beam (RB) charging and communication scheme. The scheme utilizes the semiconductor materials as gain medium, which has a better energy absorption capacity compared with the traditional solid-state one. Moreover, the telescope internal modulator (TIM) are adopted in the scheme which can concentrate beams to match the gain size, reducing the transmission loss. To evaluate the scheme SWIPT performance, we establish an analytical model and study the influence factors of its beam transmission, energy conversion, output power, and spectral efficiency. Numerical results shows that the proposed RB system can realize 16 W electric power output with 11 % end-to-end conversion efficiency, and support 18 bit/s/Hz spectral efficiency for communication.

Figures (15)

• Figure 1: Application scenarios of SWIPT (UAV: unmanned aerial vehicle)
• Figure 2: High-efficiency resonant beam SWIPT system
• Figure 3: Transmitter structure and operating principles of the semiconductor gain (DBR: distributed Bragg reflector; $E_g$, $E_{gw}$: energy level difference; $L_w$: quantum well length; $hv$: photon energy)
• Figure 4: End-to-end energy cycle ($I$: initial energy density; $R_1,R_2$: reflectivity of M1,M2; G: gain factor; $V$: Path loss)
• Figure 5: Resonator structure ($d_1,d_2,d_3,l_t$: elements distance; $a$: radius of gain medium)