Industry News

The Design of a Dual Polarized Vivaldi Array

In this article, the design of a dual polarized Vivaldi antenna array is described. The Vivaldi elements are fed by broadband microstrip-to-slotline baluns. A 2:1 bandwidth (3.4 to 7 GHz) was achieved for VSWR, gain and cross-polarization isolation. Th...
The design for the Vivaldi antenna is motivated by the need for a broadband measurement antenna for an antenna test range (ATR). The ATR is capable of a dual axis rotation to create 3-D plots and to calculate the total radiated power (TRP). 1 The TRP calculation involves the...
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Potential Applications of PBG Engineered Structures in Microwave Engineering: Part II

The second part of this article reviews the potential applications of electromagnetic bandgap (EBG) structures in enhancing the performance of waveguides and antennas. A conductor-backed coplanar waveguide (CB-CPW) free of spurious transmission and a t...
In the new millennium, the explosion of info-communication technologies has brought many new broadband design challenges. To meet these challenges, designers are required to fulfill more functionality per unit volume. In the first part of this article, the basic PBG configurations and application of PBG structures in enhancing the...
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The Analysis and Design of a User Equipment Grade, All Digital Gain Control, Direct Conversion Radio Receiver

The analysis and design of a state-of-the-art, user equipment grade, all digital gain control, direct conversion radio receiver is presented. The receiver employs a logarithmic amplifier in the analog baseband to compress the signal dynamic range befor...
The direct conversion, all digital gain control (DC-ADGC) radio receiver employs logarithmic amplifiers in the analog baseband to compress the signal dynamic range before the analog-to-digital converter. An antilog function may then be used in the digital baseband to decompress the signal. Two implementations of the DC-ADGC receiver are...
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Volterra Series Analysis of a Laser Diode Predistorter for Mobile Communication Systems

Linearization of multiple quantum well (MQW) lasers by predistortion requires optimization of the predistorter to match the laser characteristics. A Volterra series model of a predistorter is investigated over a frequency range appropriate to the secon...
The direct transponding of RF signals onto optical fiber is an important element in the implementation of efficient radio-over-fiber systems. MQW lasers exhibit transfer functions from RF to light, which generally offer good linearity, but adequate dynamic range for applications in cellular and cordless systems requires further improvement in...
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Design and Simulation of a PLL for Use in a W-CDMA RF Module

This article focuses on a special phase-locked loop (PLL) module used in a W-CDMA mobile terminal with an RF direct modulation transmitter and a superheterodyne receiver. The basic theory, design and simulation of the phase-locked loop and voltage-cont...
W-CDMA is one of the most important requirements of 3G mobile communication systems,1 and it presents a challenge to the design of RF systems for W-CDMA mobile terminals. Compared with a conventional superheterodyne structure, the direct RF I/Q modulation shows the advantages of a simple circuit configuration and low...
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Microwaves in Europe: Current Trends and Future Prospects

How strong is the European microwave industry and what influence does it have globally? What are the drivers shaping the future? Will wireless technology dominate? Will the development of new materials open up new frontiers? And what role will the defe...
European Microwave Week has become the focal point in the microwave industry calendar, when the community convenes to debate and discuss the state of the commercial climate and the strength and depth of global activity. The key questions being: What are the technological advancements coming to the fore? What...
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