UWB bandpass filter with notch‐band based on transversal signal‐interaction concepts

Abstract

Presented is a structure to design a compact ultra-wideband (UWB) bandpass filter (BPF) with excellent selectivity that enables inclusion of notch-band characteristics within the filter's passband to mitigate interfering signals that coexist within the UWB spectrum. The proposed filter topology utilises two signal paths with different electrical lengths made up of two wideband BPFs that are connected in parallel. The mechanism of generating notch-band is delineated based on transversal signal-interaction concepts. Good agreement is observed between simulated and measured performances of the UWB filter, demonstrating a fractional bandwidth of 123% (2.66-11.2 GHz) with a sharp notch-band at 5.21 GHz.

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.…”

“…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]. However, all the above designs shows good response to return loss and insertion loss but have a drawback of larger area and complexity in design that leads to increase in number of fabrication steps.…”

A Compact Uwb BPF With Sharp Roll-Off Using CPW to Microstrip Transition Structure

“…As a result, several ideas and structures have been reported to implement UWB BPF [2][3][4][5][6][7][8][9][10][11][12][13]. In [2], a modified U-shaped MMR which has five resonance frequencies was used to improve the selectivity at upper edge of the passband.…”

“…Similarly, in order to improve the selectivity, a novel MMR including open-circuited stubs and coupled-line sections was adopted in [3]. At the same time, several other UWB bandpass filters have been reported based on the transversal signalinteraction concepts [4,5]. In these filters, input signal flows through two different signal paths so as to produce extra transmission zeros at the passband edges.…”

A compact ultra-wideband power divider with favorable selectivity using transversal filtering transformer

“…1(b). When the signals pass through path 1 and path 2, and then reach at the output port, they might be equal-magnitude and out of phase [13], which might lead to the creation of transmission zeros. To study the physical mechanism of the creation of transmission zeros, the signal transmission in different coupling topologies in Fig.…”