Topic
Return loss
About: Return loss is a research topic. Over the lifetime, 11090 publications have been published within this topic receiving 97603 citations.
Papers published on a yearly basis
Papers
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TL;DR: In this article, a compact fractal boundary microstrip antenna is proposed for circular polarization (CP) by replacing the sides of a square patch with asymmetrical prefractal curves, two orthogonal modes are excited for CP operation.
Abstract: Compact fractal boundary microstrip antenna is proposed for circular polarization (CP). By replacing the sides of a square patch with asymmetrical prefractal curves, two orthogonal modes are excited for CP operation. The structure is asymmetric along the principal axes (x, y). The indentation parameter of the fractal boundary curve is optimized to design compact CP antennas. Experimental results show that 10-dB return loss and 3-dB axial-ratio bandwidths of the proposed fractal boundary Ant 2 are 162 and 50 MHz, respectively, at operating frequency of around 2540 MHz. Results show that an excellent CP is achieved with a single probe feed, besides reduction in the antenna size by applying fractal boundary concept.
87 citations
TL;DR: In this article, a stepped impedance design is introduced which allows one to realize, for example, a quarterwavelength 90/spl deg/ Schiffman phase shifter with three sections, having, theoretically, a return loss better than 30 dB over a 1:5 bandwidth.
Abstract: Meander-line phase shifters in microstrip are not well matched, because of the phase-velocity difference between the odd and the even mode in the coupled-line region. A stepped impedance design is introduced which allows one to realize, for example, a quarter-wavelength 90/spl deg/ Schiffman phase shifter with three sections, having, theoretically, a return loss better than 30 dB over a 1:5 bandwidth. Design equations are given and are confirmed by measurements on microwave integrated circuits in the frequency range 2-10 GHz.
86 citations
TL;DR: In this article, a wideband microstrip bandpass filter using transversal resonator and asymmetrical interdigital coupled lines is proposed, which achieves good insertion/return losses, flat group delay and good out-of-band rejections.
Abstract: A compact wideband microstrip bandpass filter using transversal resonator and asymmetrical interdigital coupled lines is proposed in this letter. A wide passband is first constructed using transversal signal-interference technique, resulting a pair of transmission zeros at each side of the desired passband. By driving this transversal resonator with two asymmetrical interdigital coupled lines at two sides, five extra transmission zeros are generated in the lower/upper stopbands with excellent dc-choked property, thus making up a wide passband with improved out-of-band performance. This wideband microstrip filter is then designed, implemented and experimented. Good insertion/return losses, flat group delay and good out-of-band rejections are achieved as demonstrated in both simulation and experiment.
86 citations
07 Jun 2009
TL;DR: In this article, a novel transition between conductor-backed coplanar waveguide and substrate integrated waveguide (SIW) is presented for microwave and millimeter-wave integrated circuit design.
Abstract: A novel transition between conductor-backed coplanar waveguide (CBCPW) and substrate integrated waveguide (SIW) is presented for microwave and millimeter-wave integrated circuit design. The proposed integrated transition that can provide simultaneous field and impedance matching, exhibits outstanding low-loss performances over an ultra-wideband range (entire Ka-band in our case). In this work, a generalized impedance inverter whose parameters are accurately extracted by the use of a numerical Thru-Reflection-Line (TRL) calibration technique is utilized to design the transition. Measured results for the fabricated transition in back-to-back configuration show that the insertion loss is better than 0.4 dB while the return loss is better than 20 dB over the entire Ka-band.
86 citations
TL;DR: A novel eight-band LTE/WWAN frequency reconfigurable antenna for tablet computer applications is proposed in this communication and Reasonably good radiating efficiency and antenna gain are achieved for the practical tablet computer.
Abstract: A novel eight-band LTE/WWAN frequency reconfigurable antenna for tablet computer applications is proposed in this communication. With a small dimension of 40 × 12 × 4 mm3, the proposed antenna comprises a loop feeding strip and a shorting strip in which a single-pole four-throw RF switch is embedded. The RF switch is used to change the resonant modes of lower band among four different working states, so that the antenna can provide a multiband operation of LTE700/GSM850 /900/1800/1900/UMTS2100/LTE2300/2500 with return loss better than 6 dB. Reasonably good radiating efficiency and antenna gain are also achieved for the practical tablet computer.
85 citations