No abstract

No abstract

No abstract

The miniaturized dual-mode dual-band band-pass filters (BPF) using Minkowski-island-based (MIB) fractal patch resonators are proposed in this paper. The BPF is mainly formed by a square patch resonator in which a MIB fractal configuration with 2nd order iteration is embedded in the patch. By perturbation and interdigital coupling, the wide-band and dual-band responses are obtained respectively. For miniaturized wide-band design, at 2.41 GHz central frequency it has good measured characteristics including the wide bandwidth of 2.26-2.56 GHz (3-dB fractional bandwidth of 12.4%), low insertion loss of 0.72 dB, high rejection level (−52.5/−44.9 dB), and a patch size reduction with 60.6%. For compact dual-band design, the proposed filter covers the required bandwidths for WLAN bands . The patch size reduction of 78.1% is obtained. Two transmission zeros are placed between the two passbands and resulted in good isolation.

This article presents a novel circular polarized (CP) aperture coupled stack antenna for wireless local area network and worldwide interoperability for microwave access dual-band systems. The compact stack antenna consisted of square fractal patch, aperture couple, feed line and the perturbation. The square patch is constructed with the complementary Minkowski-island-based fractal geometry. By way of adjusting the relevant parameters, we can obtain the dual-band responses at 3.5 and 5.25 GHz respectively. The CP of each band are presented. The measured 10 dB return loss impedance bandwidth are 270 MHz (7.5%) for 3.5 GHz band and 450 MHz (8.6%) for 5.25 GHz band. The 3 dB axial ratio bandwidths for each bands are 1.4 and 0.76%, the polarization of radiation patterns are both left-hand CP, and the antenna power gain are 2.84-3.1 and 0.16-2.2, dBic respectively. The proposed antenna is successfully simulated and measured with frequency responses, radiation patterns and current distributions. V C 2013 Wiley Periodicals, Inc. Int J RF and Microwave CAE 24:130-138, 2014.

No abstract

A miniaturized dual‐mode band‐pass filter (BPF) using Minkowski‐island‐based (MIB) fractal patch resonator is presented in this article. The BPF is mainly formed by a λg/4 square patch resonator, which is a MIB fractal configuration with second order iteration is embedded in the patch. By tuning the perturbation, which resulted from the fractal patch, two resonant modes are excited and a pair of transmission zeros are generated to improve the BPF performance. The proposed filter at center frequency (f0) of 630 MHz has very good measured characteristics including the bandwidth of 552–708 MHz (3‐dB fractional bandwidth of 24.8%), low insertion loss of –1.38 dB and size reduction with 76.4%. The filter performance is characterized to verify the design concept. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:594–597, 2011; View this article at wileyonlinelibrary.com. DOI 10.1002/mop.25796

ABSTRACT: