Industry News

A Novel Class of High Selectivity Filters and Duplexers in Microstrip Technology

This article describes a novel configuration for high selectivity bandpass filters and duplexers in microstrip technology. The structure proposed is made of single-sided filters, which are characterized by requirements in one passband and one stopband,...
Modern communication systems often require narrow band filters presenting high selectivity and low insertion loss. When there are also stringent requirements on the overall dimensions of the filtering structure, it could become very problematic to select a suitable class of resonators having at the same time compactness and large...
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A Novel Simulation Tool for PN Junction Varactors Based on Finite Difference Approximations

The estimation of the resistance of varactors used in integrated circuits for RF applications is a difficult task. This article presents a novel simulation tool for estimating the two main varactor parameters: resistance and capacitance. Once the capac...
Integrated voltage-controlled capacitors, usually known as varactors, are used in many electronic integrated devices for RF applications. 1 In particular, voltage-controlled oscillators (VCO) 2,3 and tuneable filters 4 are the two main applications. For good performance of integrated devices that have a varactor as a component, it is very...
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A Reduced-size Power Divider Using the Coupled Line Equivalent to a Lumped Inductor

A new method of reducing the size of a power divider using quarter-wave length transmission lines is proposed. The method utilizes a combination of shorted coupled lines instead of lumped inductors and capacitors. The new hybrid is simply fabricated wi...
In many applications, such as balanced power amplifiers, mixers and antenna systems, power dividers/combiners are required. Power dividers using quarter-wave lines become prohibitively large at the lower frequencies and result in MMIC chips of larger size and higher cost. The lumped-element approach, which uses lumped inductors and capacitors, is...
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Ask Harlan

The first edition of our new online feature
ASK HARLAN YOUR RF & MICROWAVE TECH Q&A RESOURCE You may know Harlan Howe from his twelve years as publisher and editor of Microwave Journal ®, or from his 34 years as a Microwave design engineer and engineering manager, or from his service as an IEEE fellow and past...
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WLAN Industry Will Generate $1.67 B in 2003

The wireless LAN (WLAN) industry is experiencing tremendous growth, aided by lower pricing points and standardization of technology. Allied Business Intelligence (ABI) believes that this growth will continue to accelerate, as larger technology and telecommunications companies enter the WLAN industry, bringing deep financial pockets and millions of existing customers....
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A First for Alcatel in Namibia

For what will be the first LMDS network deployment in Southern Africa, Alcatel has signed a contract with Telecom Namibia, the national telecommunications operator, to deliver its high performance Local Multipoint Distribution Service (LMDS) solution and high capacity urban microwave radio systems. The move will allow end users to...
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Siemens EDGEs Towards Asian First

The first commercial Enhanced Data Rates for Global Evolution (EDGE) project in Asia has resulted from the decision by the Malaysian mobile operator DiGi Telecommunications, a subsidiary of the Norwegian telecom company Telenor, to commission Siemens Information and Communication Mobile Group to equip its network with GSM, GPRS and...
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Motorola Starts to Deliver ZigBee Technology

In support of the draft IEEE 802.15.4 standard being driven by the ZigBee Alliance - an association of companies working together to enable reliable, cost-effective, low power, wirelessly networked, monitoring and control products based on an open global standard - Motorola Inc. is delivering hardware and software samples to...
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