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This letter proposes a new interpretation for the Z-antenna.It describes the Z-antenna as an asymmetrically-fed bent and meandered inductively-loaded dipole antenna. This explanation provides a simple methodology to design a dual-band stripline-fed Z-based antenna that operates at 1.8 and 2.45 GHz. Measurements and EM simulations validate the proposed theory. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:286-290, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27307 [ABSTRACT FROM AUTHOR]

A new compact size microstrip arbitrary coupling directional coupler (DC) based on the coupled line composite right/left handed (CL-CRLH) unit cell is proposed. The coupler is patterned on a single metal layer, does not use vias, and occupies 45 × 11 mm2 area. Its bandwidth is 400 MHz centered around 2.4 GHz and it provides −3 dB coupling coefficient. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:115-119, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27270 [ABSTRACT FROM AUTHOR]

Slow-wave coplanar striplines (S-CPS) have been implemented in the standard AMS 0.35 μm CMOS technology. Compared to conventional coplanar striplines (CPS), at 20 GHz, the proposed S-CPS line has more than 675% increase in quality factor, 54% improvement in the attenuation constant and 72% reduction in the electrical length. The RLCG model has also been extracted and the sources of losses have been identified. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:650-654, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26645 [ABSTRACT FROM AUTHOR]

In this article, a new composite right/left-handed (CRLH) antenna is proposed. The antenna is implemented by cascading dual-function coplanar waveguide coupled line CRLH unit cells. The proposed antenna has continuous backward to forward radiation. The scanning angle, radiated power and directivity increase as the number of cells increases. For nine cells, the scanning angle is 77°, the radiated power is 75%, the peak directivity is 4.2, and the total length is smaller than λ0. The circuit and EM simulations have been confirmed by measurements. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:103-107, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26483 [ABSTRACT FROM AUTHOR]

Novel three-dimensional antennas that provide either multibands or ultra-broadband are presented. The proposed structures are based on monopole antennas loaded with meander lines. For operation of multibands, the monopole is loaded with different-length meander lines connected in series. The proposed antenna has 55 × 66 × 130 mm3 volume and operates in the following bands: 200 MHz, 800 MHz, 1.1 GHz, 1.4 GHz, 2.45 GHz, 3 GHz, and 3.7 GHz. Ultra-broadband is achieved by connecting four monopoles in parallel. Each monopole is loaded with two meander lines. The resulting bandwidth extends from 400 MHz to 3.5 GHz, which is suitable for digital video broadcasting-T applications, and the size is 53 × 68 × 87 mm3. Both antennas have omnidirectional radiation patterns. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:2843-2846, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26417 [ABSTRACT FROM AUTHOR]

This article presents a balanced composite right/left-handed (CRLH) transmission line using high impedance wire.No vias are required in the proposed implementation. However, processing of double surfaces is needed. The proposed structure provides multiple CRLH bands. The concept was validated in microstrip configuration, and equivalent circuit model was proposed and theoretical expectations were confirmed by EM simulations and measurements. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1390–1393, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25215 [ABSTRACT FROM AUTHOR]

In this article we present an RF optoelectronic oscillator based on directly modulated laser diode and an all optical RF filter. The system is modeled and simulated using standard simulators. Using commercial modules and standard single mode fiber, the implemented system shows an RF oscillation with 9.8 dBm at 1.1 GHz. We also show that the use of an all optical RF filter allows a sidemode suppression ratio more than 50 dB without affecting the signal purity. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 470–475, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24069 [ABSTRACT FROM AUTHOR]

In this article, shielded coplanar striplines (S-CPS) are studied to achieve slow-wave transmission lines in a CMOS process. The slow-wave propagation is achieved by placing floating strips below the CPS transmission line. The propagation parameters of such transmission lines are derived by simulations by means of a “full wave” 3D EM software. Quality factors as high as 35 at 10 GHz together with effective dielectric constants of 78 are reported. If these simulation results are confirmed by measurements, this would open the door to the possible realization of integrated transmission line-based RF circuits such as power dividers, phase-shifters, or filters of medium bandwidth below 10 GHz. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 352–358, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24054 [ABSTRACT FROM AUTHOR]

Defected ground structure and split ring resonator are combined to form a compact dual bandstop filter or a dual pole bandstop filter. An equivalent circuit model is developed for the proposed structure and it agrees very well with EM simulation. A dual bandstop resonator was fabricated. Measurements and theoretical predictions are in a very good agreement. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 1249–1253, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22464 [ABSTRACT FROM AUTHOR]

A new family of compact rat-race hybrid couplers is proposed. The novelty of the new structures stems from the idea of utilizing the vacant space inside the conventional rat-race coupler in increasing the rat-race ring path. The couplers have been designed to operate at 1.8 GHz. The size of the new structures is 70% less than conventional rat-race hybrid coupler at the same center frequency. The measurements are in good agreement with the designed values. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 606–609, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21421 [ABSTRACT FROM AUTHOR]

An RF on-wafer probe is simulated using commercial 3D simulation software. The two-port simulated S-parameters are found to be in a good agreement with the experimental data. The model is extended to study the microstrip-mode effects in a typical RF on-wafer probe. The microstrip mode is studied as the mode between the probe coax outer conductor and the wafer chuck. The microstrip-mode reflection coefficient looking into the probe tips is determined for the first time. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 45: 324–328, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20812 [ABSTRACT FROM AUTHOR]

Two metal–semiconductor–metal (MSM) photodetectors are integrated monolithically with a coplanar waveguide transmission line to form a 1.55-μm surface-illuminated balanced photodetector. Illuminating the device with CW and taking the difference, the relative intensity noise (RIN) is suppressed by 9–10 dB. In balanced detection, a 7-dB enhancement in the intermodulation term compared to single detector is achieved. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 125–130, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10393 [ABSTRACT FROM AUTHOR]

In this work we present a new optically controlled microwave matching technique. In this technique the gap between two microwave coupled lines is illuminated by an optical spot of suitable wavelength. The structure is then used as a load in a microwave circuit. By controlling the spot intensity and position, we control the matching frequency of the circuit. The microwave behavior of the illuminated load is obtained using the MMICAD (monolithic microwave integrated circuit analysis and design) simulator. Experimental results using a p-type Si substrate in agreement with the theoretical predictions are also obtained. [ABSTRACT FROM AUTHOR]

Defected-ground coupled microstrip lines (DCL) bandpass filter is proposed. The length of the proposed filter is quarter the length of conventional coupled-line filter and it has a wide stopband and suppressed spurious resonances up to 4f0, where f0 is the filter central frequency. Five hundred and fifty megahertz single-section and two-section DCL filters were designed and fabricated. Simulations and measurements show that the rejection levels of the spurious resonances at 2f0, 3f0 as well as 4f0 are better than -11 and -14 dB for single-section DCL and double-section DCL, respectively. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2038–2039, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22590 [ABSTRACT FROM AUTHOR]