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To determine the therapeutic efficacy and safety of risk‐adapted stereotactic body radiation therapy (SBRT) schedules for patients with early‐stage central and ultra‐central inoperable non‐small cell lung cancer. From 2006 to 2015, 80 inoperable T1‐2N0M0 NSCLC patients were treated with two median dose levels: 60 Gy in six fractions (range, 48‐60 Gy in 4‐8 fractions) prescribed to the 74% isodose line (range, 58%‐79%) for central lesions (ie within 2 cm of, but not abutting, the proximal bronchial tree; n = 43), and 56 Gy in seven fractions (range, 48‐60 Gy in 5‐10 fractions) prescribed to the 74% isodose line (range, 60%‐80%) for ultra‐central lesions (ie abutting the proximal bronchial tree; n = 37) on consecutive days. Primary endpoint was overall survival (OS); secondary endpoints included progression‐free survival (PFS), tumor local control rate (LC), and toxicity. Median OS and PFS were 64.47 and 32.10 months (respectively) for ultra‐central patients, and not reached for central patients. Median time to local failure, regional failure, and any distant failures for central versus ultra‐central lesions were: 27.37 versus 26.07 months, 20.90 versus 12.53 months, and 20.85 versus 15.53 months, respectively, all P < .05. Multivariate analyses showed that tumor categorization (ultra‐central) and planning target volume ≥52.76 mL were poor prognostic factors of OS, PFS, and LC, respectively (all P < .05). There was one grade 5 toxicity; all other toxicities were grade 1‐2. Our results showed that ultra‐central tumors have a poor OS, PFS, and LC compared with central patients because of the use of risk‐adapted SBRT schedules that allow for equal and favorable toxicity profiles. [ABSTRACT FROM AUTHOR]

ABSTRACT A compact dual open-loop antenna is proposed to provide enhanced bandwidth in near-field applications in the ultra-high frequency band. The antenna generates a strong and uniform magnetic field in a near-field zone of the smaller open-loop antenna. For increased bandwidth, two open loops with individual half-wavelength perimeters are etched on each side of an FR4 printed circuit board. The antenna was fabricated in a compact overall size (dimensions, 60 × 60 × 0.8 mm3) and achieves an interrogation zone of 50 × 50 mm2 with good impedance matching and uniform magnetic field distribution in a 888-932 MHz band. Performance tests indicate that the proposed antenna has a reading distance of up to 130 mm for near-field applications and is suitable for radio frequency identification reader applications. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:2008-2012, 2015 [ABSTRACT FROM AUTHOR]

A printed microstripline-fed parallelogram monopole antenna for wideband applications is presented.This antenna is composed of a parallelogram monopole, a ground plane with three symmetrical parasitic elements, and a 50-Ω microstrip feedline. By using short-circuited parasitic elements including a symmetrical parallelogram patch and a pairs of strip lines, the proposed antenna can excite extra resonate modes to achieve wideband operation. The measured results show that the proposed antenna offers a large impedance bandwidth for 10-dB return loss is 4.74 GHz (1.82-6.56 GHz), corresponds to fractional bandwidth of 113% for central frequency at 4.19 GHz, and can cover the personal communication services, IMT-2000, 2.4/5.2/5.8 GHz wireless local area network, and 2.5/3.5/5.5 GHz worldwide interoperability for microwave access standards. In addition, measured radiation patterns exhibit reasonable radiation characteristics. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:388-391, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27278 [ABSTRACT FROM AUTHOR]

A microstrip-to-slotline transition technique is presented, for the coupling of a circularly polarized circular slot antenna in the ultrahigh frequency band.The fundamental TE11 mode of the circular slot antenna is investigated, using the magnetic current flow in the slot. In the proposed design, circular polarization (CP) is generated using a proper c-strip metal, within the circular slot structure, and connecting a strip metal to the circular slot edge, at −45° to the feeding slotline. The direct slotline feed is coupled to a 50-Ω microstrip line, on the opposite side of the substrate. Simulated and measured results indicate that the proposed structure achieves good CP radiation, in the TE11 mode. The impedance bandwidth and the 3-dB axial-ratio bandwidth for the design are approximately 22.1% and 2.5%, respectively. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2016-2023, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27013 [ABSTRACT FROM AUTHOR]

This article demonstrates a new and simple dual-band design for the planar monopole antenna.The design basically consists of a stepped-width radiating monopole element with a microstrip feedline for excitation and a circular parasitic plane for generating a resonant mode in the upper band. The measured impedance bandwidth for 10-dB return loss is from 1.98 to 3.22 GHz and 4.92 to 6.93 GHz, covering the 2.4/5.2/5.8-GHz wireless local area network bands and 2.5/5.5-GHz worldwide interoperability for microwave access bands. The measured radiation patterns are similar to typical monopole-antenna radiation characteristics. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:219-222, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26447 [ABSTRACT FROM AUTHOR]

A compact circularly polarized coplanar crossed dipole antenna with an unequal length of arms for RFID reader is designed and measured in this paper. It uses two unequal length dipoles connected in parallel to a coaxial cable feed and requires no matching network. The impedance bandwidth of the proposed antenna for S <10 dB is about 6.9% and it has a 3-dB CP bandwidth of about 1.0%. Experimental results and simulations reveal that the proposed antenna features total size of 0.15 λ in side of square substrate and 0.005 λ in height at the center frequency 924 MHz. In addition to this, the compact antenna is easily to be embedded in the holding box as transmitting antenna in handheld RFID reader. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:1172-1176, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25937 [ABSTRACT FROM AUTHOR]

A 2.4/5.2 GHz dual-band bandpass filter is designed and printed on Al2O3 ceramic substrate. The filter is based on two square-patch resonators and two T-type input/output lines. The square-ring structure is used to replace the square-patch for minimization because of longer current path. Using the higher dielectric constant and loss tangent ceramic substrate, the proposed filters have the advantages of low insertion loss, high out-of-band rejection, mini size, and simple structure. As compared to the square-patch filter, the proposed square-ring filter has 51% size reduction. And the measured results of the fabricated filters have good agreement with the simulated values. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 515–518, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24085 [ABSTRACT FROM AUTHOR]

By using a pair of shorting pins, the dual-frequency operation of a single-feed rhombic microstrip antenna with a pair of slits is presented. This shorted dual-frequency microstrip antenna can result in a much reduced antenna size, and provide a tunable frequency ratio of ∼1.26–2.33 for the two operating frequencies by varying the inset slit length. Simulated results with the use of the software also have been conducted to study the characteristics of these antennas. Details of the proposed designs are described and discussed. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 183–186, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10411 [ABSTRACT FROM AUTHOR]

A dual-frequency rectangular microstrip antenna with a pair of π-shaped narrow slots close to the nonradiating edges of the patch is experimentally studied. By varying the length and spacing of the two arms of each π-shaped slot, the proposed antenna provides a tunable frequency ratio from about 1.03 to 1.19. Details of the antenna design and experimental results are presented and discussed. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 29: 195–197, 2001. [ABSTRACT FROM AUTHOR]

A novel dual-feeding technique for a broadband circularly polarized aperture-coupled microstrip antenna operating in a 2.45 GHz system is presented. The dual feeds are placed in orthogonal directions, and are connected to a Wilkinson power divider with a 90° phase shift between its two output feedlines. Proper positioning of the coupling slots results in high port solution (>40 dB), and a purity of circular polarization is obtained. A broad impedance bandwidth (VSWR≤2) of about 54.7% and a 1 dB axial-ratio bandwidth of about 9.8% were achieved. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 28: 100–101, 2001. [ABSTRACT FROM AUTHOR]