Gye-Taek Jeong

Dual-Band Wi-Fi Antenna With a Ground Stub for Bandwidth Enhancement

Design of a compact modified inverted-L antenna with a ground stub is proposed for Wi-Fi applications. With the ground stub structure, the impedance bandwidth for 2.45-GHz band enhances from 13.1% to 15.7%, and the impedance bandwidth for 5.2/5.8-GHz bands improves from 10.1% to 19.9%. The performances of the antenna with optimized parameters are characterized in terms of reflection coefficient, gain, and radiation pattern measurements in an anechoic chamber. The measured result satisfies Wi-Fi frequency specifications.

A Low-Profile WLAN Antenna with Inductor and Tuning Stub for Broadband Impedance Matching

This paper presents a low-profile multiband antenna suitable for wireless local area networks (WLANs), using a chip inductor and tuning stub for broadband impedance matching. The proposed antenna is compact and covers three bands: 2.4-GHz (2.400–2.484 GHz), 5.2-GHz (5.150–5.350 GHz), and 5.8-GHz (5.725–5.825 GHz). The measured 10-dB bandwidths are 12.0% (2.28–2.57 GHz) in the lower band for 2.4-GHz WLANs and 39.1% (4.81–7.15 GHz) in the upper band for 5 GHz-WLANs. The measured peak gain of the antenna is between 2.7 and 4.39 dBi and the radiation patterns are omnidirectional.

Low-Profile Dual-Wideband MIMO Antenna with Low ECC for LTE and Wi-Fi Applications

This paper presents a low-profile dual-wideband multiple input multiple output (MIMO) antenna with low envelop correlation coefficient (ECC) for long-term evolution (LTE) and wireless fidelity (Wi-Fi) applications. The antenna covers LTE band 7 and Wi-Fi as well as wireless broadband (Wibro) and Worldwide Interoperability for Microwave Access (WiMax) (except for the 3.5-GHz band). To aid with integration of a practical mobile terminal, the MIMO antenna elements are placed at appropriate locations by analyzing the surface current distribution and without using any additional isolation techniques. The measured bandwidths with reflection coefficients of 20 dB in the operating frequency ranges of both LTE band 7 and Wi-Fi. Additionally, the calculated ECC is in the range , which is considerably lower than the required for MIMO applications. The measured radiation patterns are appropriate for mobile terminals, and omnidirectional radiation patterns are obtained.