Ultrawideband Bandpass Filter Using Composite Right- and Left-Handedness Line Metamaterial Unit-Cell

Abstract

The design of a new UWB bandpass filter is proposed, which is based upon the microstrip Composite Right-and Left-Handed Transmission-line(CRLH-TL). In order to bring the remarkable improvement in an attempt to reduce the size, taking the features of the conventional periodic CRLH-TL, only one unit of the structure is chosen. So the component less than a quarter-wavelength is realized to achieve the ultra wide band filtering without the loss of the original advantage of the CRLH-TL. Guaranteeing the compactness in size, the interdigitated coupled lines are used to realize the strong coupling for the design that will be shown to have the size of 'guided wavelength/9.4', the fractional bandwidth over 100%, the insertion loss much less than 1 dB, and the flat group-delay with an acceptable return loss performance in the predicted and measured results.

Design of Bandpass Filter Based on Metamaterial Concepts

“…The equivalent circuits of the CRLH-TL are shown in Fig. 1a [8], b [4], and c [22]. The filter takes on bandpass property under the balanced case and illustrates the series resonance (ω s )-and the shunt resonance (ω p )-angular frequencies as …”

Study on the Metamaterial Design Methodology to Reduce the Size of the Bandpass Filter for the Smart Grid IED

“…6, the band, the insertion and return loss and the stopband are compliant with the specifications. Now, the circuit is physically implemented following the conversion techniques in [7][8][9][10][11]. and =0.02).…”

“…H. Okabe et al added the multiple cells of the left-handed transmission section that make the dispersion curve non-linear and increase the passband to a right-handed hybrid ring while keeping the original footprint [6]. S. Kahng et al came up with one cell CRLH resonators and coupling structures between the subwavelength resonators to the compact bandpass filters for the very wideband or multi-band as the UWB, the WLAN, and the UHF and ISM dual-band applications [7][8][9][10][11].…”

“…For the last decade or more, metamaterials have intrigued RF component and system developers who seek for the ways to make compact devices and improve the electrical and RF properties [6][7][8][9][10][11]. H. Okabe et al added the multiple cells of the left-handed transmission section that make the dispersion curve non-linear and increase the passband to a right-handed hybrid ring while keeping the original footprint [6].…”