A Compact Planar Low-Pass Filter Based on SRR-Metamateria

Abstract

In this work, a novel design of a Microstrip Low-pass filter based on metamaterial square split ring resonators (SRRs) is proposed. The SRRs has been added to obtain a reduced size and high performances. The filter is designed on an FR-4 substrate having a thickness of 1.6mm, a dielectric constant of 4.4 and loss tangent of 0.025. The proposed low-pass filter is characterized by a cutoff frequency of 2.4 GHz and an attenuation level below than -20dB in the stopband. The LPF is designed, simulated and optimized by using two electromagnetic solvers CST microwave studio and ADS. The computed results obtained by both solvers are in good agreement. The total surface area of the proposed circuit is 18x18mm2 excluding the feed line, its size is miniaturized by 40% compared to the conventional filter. The experimental results illustrate that the filter achieves very good electrical performances in the passband with a low insertion loss of 0.2 dB. Moreover, a suppression level can reach more than 35 dB in the rejected band.

Compact wide stopband microstrip lowpass filter using polygon patches and meandered lines

“…For comparisons, Table 1 illustrates the measured results for some previuos works and proposed filter, where roll off rate ζ is defined as = max − min − (7) where αmax and αmin represent the −20 dB and −3 dB attenuation level, respectively, fc is the −3 dB cutoff frequency, and fs is the −20 dB stopband frequency. In this case, the bandwidth divided by center frequency of stopband is the relative stopband width (RSB) as Comparing with the other filters [2-3], [5], [7][8][9][10][11], clearly a transmission zero close to the passband is realized with T-shaped resonator and the filter has sharp roll-off rate in comparison to [2][3], [5], [7][8][9][10][11]. Moreover, the stop bandwidth of the proposed filter can be further extended by using Split Ring Resonators as [7].…”

“…However, the multimode LPF has the stopband region with low attenuation level. In [10], a novel design of a LPF based on metamaterial was introduced. The proposed filter is investigated based on square split ring resonators (SRRs) with good attenuation level in the stopband but suffers from low stop bandwidth and large size.…”

A miniaturized highly selective MTM‐inspired filter for lowpass and triple‐band bandpass performance with configurable transmission zeros and bandwidth

“…2 MTM features can be assimilated in the structures by employing composite right/left handed transmission line (CRLH-TL), split ring resonator (SRR), and complementary split ring resonator (CSRR). [3][4][5] A microstrip lowpass filter based on square-shaped SRR is proposed in Nasiri et al, 3 which offers high attenuation in stopband and considerable return loss (RL) in passband, but the selectivity is not adequate. A wideband bandpass filter that exhibits 66% fractional bandwidth (FBW) is presented with the help of shorted meandered lines and CRLH-TL.…”

A novel miniature coplanar band-pass filter for ISM applications

“…On the other hand, the split ring resonator metamaterial have the capability to exhibit negative effective permeability around their resonance frequencies as it is presented by Pendry in 1999 [20], and the complementary SRRs characterized by negative effective permittivity. Besides, the artificial left-handed metamaterials have negativepermeabilitty, permitivitty and, refractive indice, which do not exist in natural materials [21][22][23][24][25]. This letter describes a novel coplanar bandpass filter based on SRR metamaterial 181 which is operating in the ISM band that is corresponding to the 2.4 GHz frequency.…”