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oe1(光电查) - 科学论文

5 条数据
?? 中文(中国)
  • A widely tunable bandpass filter adopting novel fully tunable resonators

    摘要: A widely tunable bandpass filter adopting a novel fully tunable resonator is proposed in this letter. The fully tunable resonator is mainly consisted of an open ring, a frequency tuning structure, and a coupling tuning structure. Adopting the fully resonators, the center frequency, the input/output external Q value, and the coupling coefficients can be tuned at the same time. And the tuning range of a tunable filter adopting the novel fully tunable resonators can be expanded. The fully tunable resonators can be combined to achieve more excellent suppression performance. A widely tunable bandpass filter consisted of five fully tunable resonators with 86.5% frequency tuning range is designed, fabricated, and measured. The simulated results are in good agreement with the measured ones.

    关键词: widely tunable filter,coupling tuning structure,open ring,fully tunable resonators,more excellent suppression

    更新于2025-09-23 15:23:52

  • High-Performance Tunable Narrowband SIW Cavity-Based Quadrature Hybrid Coupler

    摘要: This letter presents, for the first time, a tunable narrowband substrate integrated waveguide (SIW) cavity-based quadrature hybrid coupler. Four high-quality factor (Q) SIW evanescent-mode cavity resonators are employed in the design and tuned using piezoelectric actuators. This allows the proposed coupler to have wide spurious-free range (SFR), low-power consumption, and high-power handling capability compared to other tunable planar couplers. The coupler can be tuned starting from 1.32 to 2.22 GHz with a measured insertion loss range from 1.29 to 0.7 dB. Over the full range, the measured 3-dB fractional bandwidth ranges from 5% to 18% while the phase error (∠S21 ? ∠S31) absolute bandwidth measured ±5° ranges from 40 to 82 MHz with an amplitude imbalance range between 1 and 0.3 dB. The measured reflection and isolation are better than 12 and 17 dB, respectively. Moreover, the coupler has a measured SFR of 5.1–3 fo (lowest–highest frequency).

    关键词: tunable quadrature hybrid coupler,Evanescent-mode (EVA) cavity,tunable resonators

    更新于2025-09-23 15:22:29

  • Continuously Tunable Resonator Using a Novel Triangular Doped Area on a Silicon Substrate

    摘要: This letter presents a continuously tunable resonator with a novel triangular doped area on a silicon substrate. The resonator and its tunable element (an n junction) are co-designed in the same flow, leading to new tradeoffs and novel behaviors. The co-design flexibility allows the active area to be drawn with any doping shape. The base of the triangular doped area is located at the end of a stub. Consequently, when the junction is forward biased with a low bias voltage, the resonator is ended by a short circuit at the triangle base. Then, by increasing the voltage, the short-circuit plan moves continuously until it reaches the top of the triangle, thereby decreasing the length of the short-circuited stub. Besides, a demonstrator validates the concept and offers a continuous resonant frequency tunability of 50%, from 2.2 to 3.3 GHz, with a bias voltage from 0 to ?1.3 V.

    关键词: co-design,Active filters,silicon (Si) devices,tunable resonators,p-i-n diode

    更新于2025-09-23 15:21:01

  • Ultra-Compact Tunable Filtering Rat-Race Coupler Based on Half-Mode SIW Evanescent-Mode Cavity Resonators

    摘要: In this paper, for the first time, an ultra-compact frequency-tunable filtering rat-race coupler based on half-mode evanescent-mode (EVA) cavity resonators is presented. Employing EVA cavity resonators in the coupler design yields attractive characteristics, such as a wide tuning range and a wide spurious-free range, while also adding filtering functionality to the device. The presented coupler is synthesized as a two pole bandpass filter using the coupling matrix method. Then, the coupling coefficients are mapped to a coupler topology. Design, simulations, and experimental validation are presented. The implemented rat-race coupler has a very compact size [0.14λg × 0.14λg (λg at 885 MHz)] achieving a 92% miniaturization in the structure footprint compared to the conventional planar one. The coupler has an 86% tuning range ranging between 0.885–1.65 GHz. Throughout the tuning range, the coupler shows an equal power splitting ratio and filtering profile with a measured insertion loss and 3-dB fractional bandwidth between 5 and 4.2 dB and 6.8% and 8%, respectively. The measured isolation is better than 30 dB. In addition, the coupler has a measured spurious-free range of 10.2 fo (at the lowest frequency) to 5.45 fo (at the highest frequency).

    关键词: rat-race coupler,tunable resonators,Evanescent-mode (EVA) cavity,tunable coupler,half-mode

    更新于2025-09-11 14:15:04

  • OMPACT CPW FED SWITCHABLE UWB ANTENNA AS AN ANTENNA FILTER AT NARROW-FREQUENCY BANDS

    摘要: The aim of this paper is to present a compact coplanar waveguide (CPW) fed switchable UWB antenna as an antenna ?lter with adjustable notched frequency bands. Novel miniaturized tunable resonators are also presented to achieve notched bands. The antenna is made tunable in notched frequency bands without any modi?cation in the basic structure. These stopbands are made tunable just by varying values of the capacitors according to our desired applications. The antenna structure is very compact having overall dimensions of 24 × 30.5 mm2 with partial ground plane. The proposed small size, variable, low cost and low weight antenna with good propagation characteristics will pave the way for UWB wireless communication applications.

    关键词: Narrow-Frequency Bands,Antenna Filter,Compact CPW Fed Switchable UWB Antenna,Tunable Resonators

    更新于2025-09-09 09:28:46