A Multilayered SIW-Based Circularly Polarized CRLH Leaky Wave Antenna

A miniaturized CRLH based SIW leaky‐wave antenna for continuous backward‐to‐forward fast beam scanning with low side lobe levels

“…Since the propagation constant (γ) is a complex quantity, we can write γ α jβ = + , where α, the real part, is called the attenuation constant, and β, the imaginary part, is called the phase constant. The dispersion diagram of the CRLH unit cell can be generated from the scattering properties of the unit cell using Equations ( 1) and (2) as follows 5,16,33 :…”

“…4 Further, the composite right/left-handed (CRLH)-based LWAs can provide backward-to-forward beam scanning due to the existence of the left-handed (LH) region, right-handed (RH) region, and zero-order resonance in between. [5][6][7] Sometimes, an LWA possesses an open stopband (OSB), which restricts it to radiate toward the broadside direction. 8,9 One of the techniques that have been used to overcome OSB in periodic LWAs is impedance matching.…”

Microwave sensor for liquid mixture identification based on composite right left hand ‐ zero‐order resonator for sensitivity improvement

“…23,24 They have been used in wireless devices to improve electromagnetic structure performances, and these are the combination of the right hand (RH) and left hand (LH) electric equivalent circuits. 25,26 The resonant frequency of structure based on CRLH is characterized by the independence of its dimension. 27,28 The CRLH is based on the principle of transmission line (TL), they can be set up to obtain zeroorder resonators (ZOR), 29,30 which is the first frequency or the dominant frequency of the circuit.…”

“…The composite right left‐handed (CRLH) resonators are considered as metamaterial structures 23,24 . They have been used in wireless devices to improve electromagnetic structure performances, and these are the combination of the right hand (RH) and left hand (LH) electric equivalent circuits 25,26 . The resonant frequency of structure based on CRLH is characterized by the independence of its dimension 27,28 .…”

“…Some research works done on sensors dealing with the chemical solution were carried out by Salim et al 44 In addition, more recent research works were performed on studying the complex permittivity or compact permittivity of the liquids, 45,46 while other research works were focusing on biological and glucose characterization 47–50 . By examining the previously published works, 1–5,16–19,23–47 it was found that the sensitivity and sensor size are still the fundamental constraints to limit microwave sensors being widely adopted. Hence, in this article, a miniaturized and improved sensitive microwave sensor with two ports is proposed to address this issue.…”