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This article presents an improved factor of merit for the comparison of center-frequency tunable bandpass filters. This study draws up a comparison between existing tunable filters for which different commonly used parameters demonstrating their performance are given. A first factor of merit that takes all the major characteristics of such tunable filters into account is introduced. A second factor of merit is proposed to evaluate the filter compactness. These new factors of merit are applied for the comparison of more than 30 recently published papers. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 985–988, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24220 [ABSTRACT FROM AUTHOR]

This paper presents the first investigation of a novel method to obtain an apodization effect on common InP ridge waveguide filters. It consists of the use of particular sampled gratings. Such apodized filters measured transmission spectra present an enhanced rejection of about 20 dB of the adjacent sidelobes, which experimentally validate the concept. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1627–1630, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21682 [ABSTRACT FROM AUTHOR]

Focuses on a study which examined a microwave microstrip line terminated by a laser illumination that alters the behavior of the microwave device. Description of the procedure; Explanation of the physical phenomenon; Simulation and results.

We have shown that, if a microstrip line deposited on silicon is illuminated at its end, a nonlinear load is obtained which behaves in microwave like a “photoinduced varactor.” We have obtained this result experimentally, and by solving the Poisson's equation and the two carrier continuity equations. © 2000 John Wiley & Sons, Inc. Microwave Opt Technol Lett 26: 10–13, 2000. [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]

A small-signal equivalent circuit model of the multielectrode lasers with saturable absorbers based on a modified formulation of the rate equations is presented. The Auger recombinations are taken into consideration because they largely modify the carrier lifetime at the high carrier densities that occur in such structures. An analysis of the bistability of the power-current characteristic is presented. The model predicts an extremely high resonance amplitude as well as a very large bandwidth up to the millimetric range, which can be very interesting for microwave optical links. The results obtained using this model are comparable to those obtained using a large-signal equivalent circuit model implanted on SPICE, the results of which are published elsewhere. The equivalent circuit obtained is a tool suitable for the study of the behavior of the multielectrode laser within a microwave optical system. [ABSTRACT FROM AUTHOR]

We present the design and realization of a 1×4 switching matrix, based on an electro-optical directional coupler. This matrix is devoted to true time delay systems. It is characterized by an original topology that reduces global power consumption down to 20 mW. Fiber-to-fiber losses are 15 dB, and the crosstalk is lower than -20 dB. © 1998 John Wiley & Sons, Inc. Microwave Opt Technol Lett 18: 243–246, 1998. [ABSTRACT FROM AUTHOR]

A microwave integrated, tunable, low-pass filter is presented. This coplanar filter exhibits a wide tuning range of the cutoff frequency (±19% around 4.3 GHz) and a -30 dB stopband that extends up to 30 GHz. Insertion loss is 1.5 dB at low frequencies and return loss is better than 14 dB in the passband. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2566–2568, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23707 [ABSTRACT FROM AUTHOR]

We report on the opto-microwave characterization of InP waveguide-coupled to microcavity disk resonators. The lateral waveguide confinement is obtained by deep inductively-coupled plasma reactive-ion etching (ICP-RIE) through the guiding layer. We demonstrate the propagation of microwaves on an optical carrier in this resonant structure, which behaves as an opto-microwave filter or demultiplexer. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 45: 315–317, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20808 [ABSTRACT FROM AUTHOR]

InGaAsP/InP micro-waveguides are fabricated by a deep (>3 μm) Reactive Ion Etching. The devices losses are measured by the Fabry–Perot technique for guide width contained between 10 μm and 0.5 μm. The measured losses range from 2 dB/mm to 14 dB/mm. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 216–218, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11333 [ABSTRACT FROM AUTHOR]

We have measured the noise performance of GaInAs PIN photodiodes in the microwave frequency range. We show that the frequency response of the photodetector can be deduced from their photocurrent shot noise spectra. The noise level has been measured using a setup which is based on heterodyne microwave mixing. [ABSTRACT FROM AUTHOR]

The purpose of this article is to compare the microwave performance of three photodetector types, an lnGaAs/lnP p-i-n photo-diode, an interdigitated lnA/As/ lnGaAs/ lnP metal-semiconductor-metal (MSM) photodiode, and an interdigitated lnGaAs/ lnP photo-conductor (PC). Static and dynamic characterizations have been carried out at 1.3.-µm wavelength using a directly modulated laser diode. Our experiments show that photoconductive detectors exhibit the best sensitivity for frequencies up to 3 GHz. [ABSTRACT FROM AUTHOR]

We describe an optically controlled microwave attenuator based on a microstrip reverse directional coupler where optical illumination modifies the loads at the coupling and transmission ports. A tunable attenuation up to 10 dB was measured at the center frequency, Experimental and theoretical results are compared and agree well. [ABSTRACT FROM AUTHOR]