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A wideband bandpass filter (BPF) based on two dual‐mode stub‐loaded stepped‐impedance resonators (SLSIRs) with mixed electric and magnetic coupling (MEMC) is proposed. Magnetic coupling is realized by using a transmission line, open end‐coupling and inter‐digital‐coupling provide a weak and a strong electric coupling, respectively. Due to the canceling effect of MEMCs, together with its harmonic effect, four transmission zeros (TZs) aside the passband are created and the selectivity of the filter is therefore highly improved. To verify the proposed design, a four‐pole wideband BPF operating at 3.35 GHz with 3 dB fractional bandwidth (FBW) of 32.96% is designed, fabricated, and measured. The measured minimum insertion loss is 0.95 dB, and the passband return loss is better than 11 dB. [ABSTRACT FROM AUTHOR]

A novel ultra‐wideband (UWB) bandpass filter (BPF) with a very compact size and improved out‐of‐band performance is proposed in this letter. The main circuit structure is a composite right‐/left‐handed transmission line unit cell, which has UWB bandpass characteristic as well as compact size. Moreover, two anticoupled line structures added at both ends of the unit cell can produce a new resonant mode and three transmission zeros, so the passband response and upper stopband performance can be improved. The proposed filter is implemented and measured, which shows its 3 dB passband ranges from 3.3 to 10.9 GHz with a fractional bandwidth of 110.9%. Its insertion loss is about 0.6 dB at the centre frequency, while the return loss is better than 13 dB. In addition, the measured results also show the proposed filter has a wide stopband from 11.4 to 30 GHz, whose rejection level is greater than 18 dB. The size of the filter is only 7.4 × 6.4 mm, equal to 0.22 × 0.20 λg. Both the simulated and measured results are in good agreement. [ABSTRACT FROM AUTHOR]

In this article, a broadband beam scanning antenna array is proposed in Q‐band attributed to miniaturized size, wideband and high integration. A patch antenna element is utilized with a back cavity, which is formed by metallic via holes and ground plane. A 1 × 4 series fed sub‐array is implemented by the patch element using multilayer PCB. Four symmetrical sub‐arrays and Butler matrix feeding network are used to form the antenna array with high gain and decrease side lobes. The Butler matrix is implemented by substrate integrated coaxial line, which provides low loss of around 0.09 dB/mm from 40 to 50 GHz. The measured antenna array bandwidth is 9.8 GHz (21.8%) under the condition of voltage standing wave ratio less than 2. The main beam of the antenna array in azimuth direction is tilted to −28.5°, −14.1°, 18.4° and 35.6° and the gains are 13.11, 13.88, 14.02 and 11.78 dBi at 45 GHz, respectively. Both the measured and simulated results agree well. [ABSTRACT FROM AUTHOR]

In this letter, a novel miniaturized and low insertion loss 60GHz on‐chip bandpass filter (BPF) is presented, which is fabricated by a standard 0.13 μm CMOS process. This BPF is mainly composed of a three‐line coupled structure. The selectivity of the filter is improved by introducing two transmission zeros on both sides of the desired passband because of the source‐load coupled structures. In addition, the gap between the three coupled lines can affect the coupling strength to determine the fractional bandwidth (FBW) of the filter. The miniaturization of the filter is also achieved by folding the coup led line of a quarter wavelength. The overall size of the fabricated BPF chip is 267 μm × 376 μm. The measured results show that the insertion loss and fractional bandwidth of the filter at the center frequency of 60 GHz are −2.03 dB and 47%, respectively. The simulated and measured results are in good agreement. [ABSTRACT FROM AUTHOR]

ABSTRACT This article presents a dual-band LC voltage switched oscillator (VCO), which can be regulated between 3.6-4.5 GHz and 6.5-7.8 GHz frequency bands. The VCO is realized employing a tunable LC tank with switched capacitors, which makes the dual-band operation available. The VCO has been implemented in 0.13 μm SiGe BiCMOS technology, and draws around 5 mA and 5.2 mA in the core circuit with a 1.6 V supply at 4.22 GHz and 7.3 GHz, respectively. The measured phase noise performance of the VCO are −103.36 dBc/Hz for 4.22 GHz and −104.69 dBc/Hz for 7.3 GHz at 3 MHz offset. The core area of the chip is 0.13 mm2 based on the use of a symmetric inductor. © 2017 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:1439-1441, 2017 [ABSTRACT FROM AUTHOR]

ABSTRACT This article proposes a 3-5 GHz IR-UWB (impulse radio ultra-wide band) impulse generator. The impulse generator is mainly composed of an ultra-narrow pulse generator and an on-chip filter. The IR-UWB impulse generator is implemented in 0.13 μm CMOS, while the chip size is 0.29 mm2. The peak-to-peak voltage of the output signals is 600 mV. When the data rate is 10 MHz, the circuit consumes 6.95 mW. The impulse generated can fulfill the FCC spectral mask for indoor UWB systems. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2242-2245, 2016 [ABSTRACT FROM AUTHOR]

In this article, an approach to miniaturize bandpass filter with half-wavelength resonators is proposed.Theoretical analysis shows that the passband of the filter can be shifted to lower frequency by shunt open stubs. Furthermore, to prove its practical viability, three miniaturized bandpass filters with T-shape, comb-shape, and interdigital-like shunt open stubs are designed, fabricated, and compared. The filter with interdigital-like shunt open stubs has the minimized size 13.3 × 8.5 mm2 and maximum insertion loss around − 1.7 dB. The simulated and measured results agree well. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:890-894, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27465 [ABSTRACT FROM AUTHOR]

A microstrip-based segmented coupling reader antenna is proposed for near-field ultra high frequency radio frequency identification applications. The measured reading distance is 13.5 cm in the air and the measured bandwidth is around 55 MHz (895-950 MHz) under the condition of voltage standing wave ratio less than 2.0, which covers the Federal Communications Commission standard (902-928 MHz) completely. In addition, the simulated far-field gain is around 4.7 dBi. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26144 [ABSTRACT FROM AUTHOR]