MIMO WPT System Optimisation and Prototyping

Wireless Power Transfer Explained

Wireless power transfer is a promising technology to overcome the issue of battery recharging and replacement in IoT. The main challenge of WPT is to improve the output DC power of the rectenna without increasing the transmit power.

In this talk, we introduce the multiple-input and multiple-output (MIMO) wireless power transfer (WPT) system so as to enhance the output DC power of the rectennas. Two combining schemes for multiple rectennas at the receiver, DC and RF combinings, are also modelled, analysed, and optimised. Two types of performance evaluations, based on the nonlinear rectenna model and based on an realistic and accurate rectenna circuit simulations, are provided to show that the output DC power can be linearly increased by using multiple rectennas at the transmitter and receiver and that RF combining outperforms DC combining in terms of the output DC power level due to the nonlinearity of the rectenna.

Preliminary prototyping of the MISO WPT system with and without cooperative transmit antennas are also introduced. It is shown that the output DC power can be effectively boosted by adapting to channel state information (CSI). Conclusions and future work will be discussed.