Wireless power transfer technology for wireless sensor networks

Jānis Eidaks, Romāns Kušņins, Kristaps Gailis, Ruslans Babajans, Darja Čirjuļina, Deniss Kolosovs, Dmitrijs Pikuļins

Description of the Technology

This approach to RF WPT integrates advanced techniques such as multihop nodes (MHN) and intelligent reflecting surfaces (IRS) to improve power transfer efficiency and directionality:
• MHN enables the relay of RF energy over longer distances by breaking the path into smaller, more manageable segments. Each node acts as a receiver and a transmitter, ensuring seamless power transmission across broad areas and complex environments.
• IRS dynamically adjusts the RF power beam's direction. By altering the phase and angle of reflected waves, IRS enhances the precision of power delivery, overcoming obstacles and focusing energy on target devices. This ensures higher efficiency, reduced energy loss, and the ability to circumvent physical barriers.

 

Applications

• IoT Devices & Smart Homes: Power sensors, smart meters, and home automation systems without frequent battery changes. • Agriculture: Enable wireless sensor networks for precision farming by powering remote IoT devices in fields. • Healthcare: Ensure continuous operation of medical devices, wearable sensors, and other critical equipment

Advantages

• Power Transmission Frequency: ISM band 868 MHz.
• A possibility of adjusting frequencies depending on the use case, environment, and regulations.
• Range Extension via MHN: A power level of 3 mW can be delivered to receiving devices at the 7 m maximum distance (d1+d2).
• IRS Beamforming and Directionality: the reflection angle a1 30° to 50° provides 300 µW at 2 m distance.
• A possibility to dynamically adjust the power output based on distance, device requirements, or environmental conditions.

Keywords

wireless power transfer,wireless sensor networks