Zhu Liu

• Dalhousie University

Channel state information (CSI) is usually estimated by the user equipment (UE) and fed back to the base station (BS). The quality of the CSI received by the BS significantly impacts the performance of large-scale multiple-input-multiple-output (MIMO) system. The CSI feedback consumes a large amount of uplink bandwidth resources, especially in mass...

In this letter, an optically invisible antenna with high gain and wide band is investigated by utilizing transparent ionic liquids for millimeter (mm)-waves vehicular communications. The antenna consists of ionic liquids, acrylic containers, and a transparent conductive film (TCF). The wideband and high-gain operating characteristics are achieved b...

In order to improve the efficiency and accuracy of antenna optimization, an adaptive evolutionary neural network (AENN) based optimization design method for wideband dual-polarized antenna is proposed. The proposed AENN is composed of two networks. The first network is used to predict the structural parameters of the antenna, and the second network...

This paper presents a novel wearable antenna sensor based on localized surface plasmons (LSPs) for communication and non-invasive sweat monitoring. The sensor is made up of corrugated plasmonic structures based on the conventional printed monopole antenna, which achieves multi-band and miniaturization. The physical dimensions of the antenna sensor...

A wearable radio-frequency (RF) energy-localized harvester with multiple antennas and spoof surface plasmon (SSP) structure for multibeam radiation is presented to power the Bluetooth sensor module. The harvester contains four separate antennas connected by SSP waveguides, while the loop is applied to excite the structure to generate multibeam radi...

The electromagnetic (EM) coupling effects of microstrip antenna has become increasingly prominent in complicated electric system. In this paper, a hybrid method is proposed based on the combination of cavity eigenmode theory and BLT equation. Firstly, the internal electric field generated by the transmission lines inside the resonant cavity is obta...

This brief demonstrated a body-wide RF energy harvester based on textile spoof surface plasmon (SSP) antenna array for wearable wireless power transmission. This harvester includes four patch antennas and SSP waveguides to form an SSP antenna array integrated with clothing to harvest the incident RF energy. Then, a loop and rectifier are integrated...

In this paper, the gradient elliptical slots (ES) are designed to enhance the operating bandwidth of the Vivaldi antenna (VA) in the relatively low frequency band. The antenna EVA is implemented by integrating the elliptical slots to the edge of the VA, which extends the low frequency operating point from 7.4 GHz to 5.4 GHz while obtaining the mini...

Misalignments between the transmitting and receiving coils of a wireless power system can significantly reduce power transfer efficiency (PTE). In this paper, we propose a novel magnetically coupled resonant wireless power transfer (MCR-WPT) system with good misalignment tolerance for wireless charging applications. Specifically, we employ three in...

Research and development of wireless power transfer (WPT) systems has attracted much attention in recent years for their potential widespread applications. One of the much desirable features of a WPT system is load-independence. In this letter, we propose the insertion of a simple T-type network into a multi-receiver WPT magnetically coupled resona...

we present a shape-reconfigurable modularized magnetically-coupled resonance wireless power transfer (MCR-WPT) array system for multi-purpose wireless charging applications. In it, three interconnected resonant modules are employed for the transmitter and two interconnected resonant modules for the receiver. Such a modularized configuration allows...

This letter presents a tank system for wireless power transfer with magnetically coupled resonance. It contains two interconnected transmitting resonant coils placed perpendicular to each other and forms a magnetic resonant tank. Due to the combined effects of these two transmitting coils, there will always be magnetic flux that goes through the re...

This letter presents a new planar L-shape transmitter for magnetically-coupled resonance wireless power transfer (MCR-WPT) system. In it, a second transmitting resonant coil is added in the L-shape position to further improve power transfer performance and to mitigate the adverse close-distance frequency splitting effects; it does not occupy space...