Jungang Yin

Characterization of multi-port Eleven antenna for use in MIMO system

The purpose of the present paper is to investigate the MIMO performance of the L-band multi-port Eleven antenna. Both a single- and dual-polarized lab model are investigated, both having 4 ports per polarization. The 4 ports per polarization are normally combined in a 180 deg hybrid to produce sum and difference patterns, but we investigate them here as individual ports in an antenna for a MIMO system. The embedded element efficiency, diversity gain and maximum available capacity of both models have been measured in a Bluetest reverberation chamber. The measured results show that the Eleven antenna is a flexible antenna that can be used with around 11 dB gain and arbitrary single or dual polarization in a Line-Of-Sight system and with 4 or 8 independent ports in a MIMO system, and it can easily be switched between these two modes by appropriate combination of the antenna ports.

Low-profile ultra-wideband directional dipole antenna as a feed for reflectors in radio telescopes

In this paper, a small top plate is found useful to improve the impedance bandwidth of an ultra-wideband dipole antenna horizontally above a ground plane. A linearly-polarized prototype based on this new and simple design methodology can operate over nearly 3.5:1 bandwidth with return losses better than 10 dB, and with nearly stable radiation patterns, high BOR1 efficiency and aperture efficiency over the entire operating band.

A dual-band slotted trapezoidal inverted-F antenna for indoor WLAN communications

This letter presents a new directional dual-band slotted trapezoidal inverted-F antenna (IFA) for indoor Wireless Local Area Network (WLAN) applications. The dual-band performance can be obtained by tuning the lengths of the inner symmetrical trapezoidal slots and the outer trapezoidal arms in a nearly independent manner. The measured results show that the proposed antenna can provide two separate impedance bandwidths (return loss better than 10 dB) around 180MHz and 750MHz for 2.4/5.1-5.8 GHz WLAN bands, respectively. Good radiation performance and roughly constant in-band antenna directivities are also observed.

A directional dual-band rectangular inverted-F antenna with Eleven slots for WLAN applications

A directional dual-band rectangular inverted-F antenna for WLAN applications is presented in this paper. By using the so-called Eleven-slot, the dual-band operation is obtained. The antenna have been designed and simulated in CST Microwave Studio. The results show that the antenna can provide wider impedance bandwidth in the higher resonant frequency by extending the slots to outside of the edge of the patch. The simulated 10dB impedance bandwidth in the dual-band are about 260 MHz (2.23-2.49GHz) and 630 MHz (5.21-5.84GHz) at dual bands, respectively, making it capable of covering the dual WLAN bands. Good radiation performances and nearly constant in-band antenna directivities are observed as well.

Several new ultra-wideband antenna systems for radio telescopes and industry sensor imaging process

This paper presents an overview of several ultrawideband (UWB) antenna systems recently developed at Chalmers for applications in future UWB radio telescopes and industry sensor imaging process.