Highly Reconfigurable Dual-Band Coupler With Independently Tunable Operating Frequencies

Novel Dual-Band Beam-Scanning/Switching Network Based on a Hybrid Coupler With Synchronously Tuned Phase Differences

“…Electronically tunable couplers with tunable operating frequency [18], [19], tunable power-dividing ratio [20]- [22], or both [23]- [25] were extensively reported. Owing to the adaptability to providing flexible phase compensation in a beamformer, such as in the switched-beam Butler and Nolen matrices, and the contribution to optimum performance of reflectometers [26], [27], a coupler with tunable phase difference between through and coupled ports has received increasing attention and several tunable or switchable solutions [28]- [33] were proposed in the recent literature.…”

“…and the characteristic impedance Z1 can readily be obtained by (19). Finally, the input impedances of the stub networks at f1 and f2, i.e., Zs1(f1), Zs1(f2), Zs2(f1), and Zs2(f2), can be deduced from (18) and they are shown at the bottom of this page.…”

“…Given two operational frequencies f1 and f2, power division ratio K=1, and the phase difference f1, the microstrip impedance Z1 or Z2 and electrical length q1 or q2 can be computed by (16b), ( 17), (19), and (20); moreover, the required Zs1 and Zs2 at each frequency can be computed by (21). Note that q1 and q2 are decided by f1 and f2 only.…”

Simple Coupled-Line Tunable Bandpass Filter With Wide Tuning Range

“…Reconfigurable or high-performance microwave devices, such as power dividers [1]- [3], phase shifters [4]- [7], couplers [8]- [10], and filters [11]- [33], are extensively studied in past several years. Due to the reconfigurability, these key components used in modern wireless communication systems are capable to realize the agile frequency to support different standards, as well as reduce the size and complexity of systems.…”

Design of Novel Reconfigurable Filter With Simultaneously Tunable and Switchable Passband

“…Modern wireless communication systems frequently demand the components with reconfigurability to realize more functions within the limited circuit space or cost. Various kinds of reconfigurable components, such as power divider [1]- [4], coupler [5], [6], duplexer [7], antenna [8], [9], and filter [10]- [12] have been studied to satisfy the application requirements of RF front-ends. In among, bandpass filter (BPF), as one of the most important devices that can transmit interested signal and eliminate unwanted interference, play a key role in the communication system.…”