A dual‐mode tunable bandpass filter for GSM, UMTS, WiFi, and WiMAX standards applications

Abstract

Summary This paper presents a dual‐mode tunable bandpass filter (BPF) for global system for mobile communication, universal mobile telecommunications system, wireless fidelity, and worldwide interoperability for microwave access standard applications. The proposed filter consists of a stepped‐impedance resonator, single resonator, and coupled line, which are loaded with varactors. The center frequency and bandwidth of the proposed filter can be tuned with tuning varactors. Furthermore, the measurement results show that the BPF can be tuned over the frequency range of 1.8 to 2.5 GHz. Moreover, the bandwidth can be changed at each certain frequency. Furthermore, using PIN diodes, a bandstop filter is added to the tunable BPF to reduce the out‐of‐band frequencies around the desired frequencies. The values of LC equivalent circuits are calculated, and the results are compared with those obtained from the layout of the proposed structure. Finally, the measurement results justify the simulation results.

Redefinable planar microwave passive electronics enabled by thermal controlled VO2/Cu hybrid matrix

“…However, replicating reconfigurability in the sense of an FPGA is difficult in the microwave frequency domain because in addition to guiding the steady state flow of a signal like an FPGA, the time-varying electromagnetic (EM) field on a high-frequency device needs to be redistributed in space on demand for impedance matching and EM coupling purposes. Current studies of reconfigurable microwave passive devices largely focus on the reconfigurability of a specific performance metric, such as frequency reconfigurability ( Yang et al., 2020 ; Sumana et al., 2021 ; Chen and Chu, 2016 ), bandwidth reconfigurability ( Maragheh et al., 2019 ; Song et al., 2019 ), polarization reconfiguration ( Anantha et al., 2017 ; Li et al., 2020 ), radiation pattern reconfigurability ( Prakash et al., 2021 ; Zainarry et al., 2018 ; Boukarkar et al., 2018 ), etc., while functional reconfiguration is seldom reported.…”

A quad‐band defected microstrip structure loaded bandpass filter for standard GPS , WiFi , WLAN , and WiMAX applications

“…Some other features of tunable microstrip BPFs are lower fabrication costs and less circuit complexity. 2 A compact BPF with good return loss is presented in Ref. [3] using steppedimpedance resonator (SIR).…”

“…With advances in multiband wireless systems, tunable microstrip BPFs have become quite popular for radio frequency devices. Some other features of tunable microstrip BPFs are lower fabrication costs and less circuit complexity 2 . A compact BPF with good return loss is presented in Ref.…”

Planar circuit analysis of ultra‐wideband millimeter‐wave inductor using transmission line sections

“…Therefore, to improve the performance of input/output impedance matching networks for various circuits such as wideband millimeter-wave power amplifier, 1 high gain amplifier, 2 low noise amplifiers, [3][4][5] low power amplifiers, [6][7][8] high-efficiency broadband power amplifiers, [9][10][11] and V-band mixer, 12 the ultra-wideband inductors are required. Also, the proposed ultra-wideband inductor could be used in the design of a microstrip wideband bandstop filter, 13 tri-bandstop filter, 14 dual-mode tunable bandpass filter, 15 and ultra-wideband bandpass microstrip line filters. 16,17 In the design of ultra-wideband inductors by microstrip lines, it is possible to use the cascaded rectangular microstrip segments with different characteristics impedance.…”