Compact ultra‐wideband notch‐band bandpass filters using multiple slotline resonators

Abstract

A novel extremely compact ultra‐wideband (UWB) bandpass filter (BPF) with a notch band is presented.The multiple slotline resonators have been applied to construct the UWB BPF and implement the notch band within the UWB passband. Based on the transmission‐line theory, the equivalent‐circuit model of the proposed UWB notch‐band BPF has been developed. The upper cut‐off frequency and passband bandwidth of the UWB BPF, as well as the center frequency of the notched band can be adjusted by tuning the structural parameters. The proposed compact UWB notch‐band BPF using multiple slotline resonators has been designed, simulated, and measured. The measured results agree with the simulated ones closely. The notched band centered at around 5.7 GHz has 10‐dB rejection fractional bandwidths of about 2%. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1132–1135, 2012

Introduction of dielectric phthalocyanine copper into nano-structure Fe3O4 for excellent microwave absorption

“…Besides, as one significant parameter, the reflection loss (RL) was used to evaluate the microwave-absorbing capacity. It could be calculated by the following equations based on the transmit-line theory [33,34]:…”

A Compact UWB BPF with a Notch Band using Rectangular Resonator Sandwiched between Interdigital Structure

“…The insertion loss in simulated result within the passband is less than 0.7dB and the return loss is more than 19.37 dB. The measured results shows insertion loss less than 1 dB and return loss greater than 15.9 dB, see Figure 5 Table 1 describes the comparative study of the performance of proposed design with that of already existing design mentioned [14], [15], [16], [17], [18], [19] and [20]. In this paper a planar, compact UWB BPF using a rectangular resonator sandwiched between two interdigital structures is designed, implemented and measured.…”

“…In one of the work, a coplanar waveguide (CPW) technique is used to obtain a notch band [14]. A ring resonator with two stepped impedance stubs as well as multiple slotline resonators has been used to create a notch band in UWB BPF [15] and [16]. A compact UWB BPF has been realized recently for better notch band characteristics using dual stub loaded resonator and folded T-shaped stepped impedance resonator [17] and [18].…”

Only Ku-band microwave absorption by Fe3O4/ferrocenyl-CuPc hybrid nanospheres

“…Moreover, the minimum reflection loss of the as-prepared hybrid nanospheres from L-band to X-band is higher than À 1.5 dB. So the hybrid nanospheres have potential application in notch filter in Ku-band, which is kind of special electromagnetic shielding device and eliminates a single frequency or narrow band of frequencies [31,32].…”