Country: South Korea
Year Submitted: 2019
University: Sungkyunkwan University
List of Team Members (with year of graduation): Arif Abdul Aziz (expected 2020)
Faculty Advisers: Kaewon Choi, Ph.D.
Main Contact Email Address: email@example.com
Title: LRWE Trans-Location: Long Range Wireless Energy Transfer and Localization
Description: The LRWE Trans-Location is a project that has been developed aiming to introduces a new alternative and ready to be commercially used long-range wireless charging device. Unlike the near-field wireless charging commercial product, (e.g. wireless phone charger), the LRWE Trans-Location utilize the property of electromagnetic wave to wirelessly transfer the energy from the far distance and at the same time to discover the location of the receiver devices. Besides that, with the implementation of massive MIMO technology, the power transfer efficiency and the operational range can be significantly improved by using beamforming technique implemented on the LRWE Trans-Location system.
The LRWE Trans-Location project consists of 2 main parts:
The Challenge: The implementation of Wireless Sensor Network (WSN) and Internet of Thing (IoT) devices have been rapidly increasing along with the better performance of the communication technology such as LTE and soon to be globally released 5G. With high data rate, low latency, and massive device connectivity, 5G become a key technology for the implementation of the massive number of IoT and WSN devices.
Since the source power of the WSN and IoT devices only available from the build in battery, power availability also becomes a critical issue. Replacing the battery is the common way to overcome the power deficiency when the battery starts to dry out. This method becomes almost impossible with the massive number of WSN and IoT devices installed, due to high cost and time consuming especially for the devices that installed on the remote area with very limited access. With this problem, we need to address a new solution where the power deficiency of massive number WSN and IoT devices can be solved with lower cost and less time consumption.
The Solution: The LRWE Trans-Location project offers an alternative method by wirelessly recharge the build in battery of WSN and IoT devices from far distance, where this method will save time, complexity and cost compared to the traditional method such as battery replacement. This benefit will more impactful when WSN and IoT devices installed on the remote area with very limited access. In this case, the engineer needs special equipment (e.g. climbing gear), special skill (e.g. climbing skill), and needs a lot of time required only to get close to the device then replace the battery. This complexity, cost, and time to replace the battery can be overcome by using LRWE Trans-Location project. With LRWE Trans-Location deliver the power constantly, any WSN and IoT devices can be built by only using a super capacitor as battery replacement or even battery-less devices rather than using disposal battery that very toxic and harmful for the environment. Besides that, the production cost to mass produces the WSN and IoT devices can be reduced by replacing the battery with a cheaper super capacitor or removing the battery for the battery-less device.
Beamforming technique implemented in the LRWE Trans-Location project utilizes the feature of massive antenna array by combining individual waveform from each antenna patch into a beam directional wave traveling in a specific direction. This technique is simply done by 2 steps. First, power beacon needs to send a combination of training slots towards random direction in front of the massive antenna to allocate the location of the WSN or IoT devices. After the location of receiver estimated, then the power beacon configures different phase combination on each antenna to shape a beam directional wave toward the position of the WSN or IoT devices. These 2 steps repeated every 100ms maintaining synchronization between power beacon and receiver device, especially if the WSN and IoT device change its position.
LabVIEW integrated on the Power Beacon, offering an engineering user interface that can displaying measurement data acquired from the WSN and IoT devices, (e.g. battery level and Received Signal Strength Indicator (RSSI)) in real time. With the user interface on the LabVIEW program, we can directly observe the condition for each WSN and IoT devices without close inspection that consumes too much time. The specific program build inside the LabVIEW also computes complex algorithm for performing beamforming and localization process to wirelessly transfer the energy from the far distance toward the position of the WSN and IoT devices. The low latency control signal to set the phase and output power for each antenna delivered to the power beacon by using the NI PXI Chassis with NI FPGA installed on the PXI slot. As additions to the Power Beacon, NI USRP-2920 is being used as the RF signal source generating a continuous wave (CW) signal at 920 MHz reserved for wireless energy transfer. Besides that, complete features available on the NI VirtualBench become the perfect device as a DC power supply and measurement equipment by utilizing the oscilloscope and digital multimeter feature on the VirtualBench while paired with the LabVIEW interface. Thanks to the robust performance of the NI products and ecosystem, heavy computational process and displaying the measurement results in real time can be done quickly by using LabVIEW.
The Conclusion: The LRWE Trans-Location project offers an alternative method that will save a lot of time, complexity and cost by wirelessly recharge the build in battery of WSN and IoT devices from far distance especially for WSN and IoT devices installed on the remote area with very limited access. To our best knowledge, this project is the first work to implement massive antenna array for the long-range wireless power transfer with the operating distance up to 50 meters, delivering the power to the Wireless Powered Sensor Device (WPSN) testbed. This project has been published on the Korean domestic and International journal with more detail and specific explanation for different experiment setup.
List of publications, that involving LRWE Trans-Location project:
Time to Build: This project started from August 2016 until January 2017 focus on designing and building the hardware from scratch. After the hardware completed, until now we still conducting various experiment by involving LRWE Trans-Location project as the main equipment, with various experiment setup and additional equipment, with the result of several domestic and international journal papers.
Video link with various experiment set-up: