Search

A topology of a compact planar microstrip filter with a notched band is introduced, which employs a split-ring resonator defected ground structure (DSRR). Folded short-circuited stubs are used to realise the bandpass filter with good selectivity and out-of-band characteristics. By employing a split-ring resonator defected ground structure, a narrow notched band was introduced to reject the undesired wireless local-area network (WLAN) radio signals. The measured insertion loss is less than 1.6 dB, the return loss is more than 13 dB, and the variation of group delay is less than 0.5 ns throughout most of the two passbands. The width of the narrow notched band is about 1 GHz and the attenuation is more than 25 dB at the centre frequency of 5.4 GHz. [ABSTRACT FROM AUTHOR]

A single-sided left- and right-handed metamaterial, which is called a triangular left- and right-handed resonator composed of symmetric paired triangular split-rings and middle wires, is discussed. The frequency dependence of the transmittance shows a right-handed transmission window centred around 9.9 GHz and a left-handed transmission peak around 10.9 GHz, both displaying comparable high transmission levels. The left- and right-handed behaviour is assessed by retrieved effective parameters, surface current distribution and comparison of the phase delay between two slabs of different units. [ABSTRACT FROM AUTHOR]

A new design of a compact ultra-wideband (UWB) antenna with multiple band-notched characteristic is presented. The proposed antenna utilised a C-shape ground to realise miniaturisation and two mushroom-type electromagnetic-bandgap (EBG) structures to create notched bands. The EBG structure which comprises a slotted patch and an edge-located via can form a narrower notched band than many other structures, thus the presented design effectively saves many more useful frequencies. The antenna achieves an operation frequency band from 3 to 13GHz with good rejection to the Worldwide Interoperability for Microwave Access (WiMAX) and the wireless local area network (WLAN) bands in both simulated and measured results. [ABSTRACT FROM AUTHOR]

A tri-band bandpass filter (BPF) using a novel square ring loaded resonator (SRLR) is presented. The SRLR can generate a tri-band response by tuning its geometric parameters. Moreover, it can build the high-order tri-band BPFs using the proposed resonators because of the sufficient coupling between adjacent resonators. A fourth-order Chebyshev tri-band BPF centred at 2.4, 3.5 and 5.2 GHz is designed and fabricated. Measurement results agree well with the full-wave EM simulated results. [ABSTRACT FROM AUTHOR]