Semiconductors / Integrated Circuits

Overcoming Hard Limiter Suppression

For about half a century the suppression effects of bandpass hard limiters on various combinations of signals and interference have attracted widespread interest. 1-4 Certain "rules of thumb" have accreted around a variety of theoretical results. The purpose of this article is to revisit issues of interpretation and to...
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Effects of Grounding and Bias Circuit on the Performance of High Frequency Linear Amplifiers

The design of a high frequency amplifier is normally based on the S-parameters supplied by the manufacturer of the active device. However, in a practical design, these parameters are affected by the DC bias network and the grounding of the active devic...
In the design of high frequency power amplifiers, one of the parameters is the stability of the active device. The stability of the active device is determined by the Rollet stability factor K. If K > 1, then the active device is unconditionally stable and the design of the...
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Ultra-wideband Radio - The New Part 15

Summary of the possible interactions between ultra-wideband and other wireless communications systems based on newly adopted rules by the Federal Communications Commission
Ultra-wideband (UWB) radio technology enables several important applications, including ground penetrating radar, imaging, location tracking and low cost, short-range communications. With the recent Federal Communications Commission (FCC) approval of rules for operation of UWB devices under Part 15, devices aimed at these, and possibly other, applications will soon be...
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Hybrid Synthesizer Tutorial

Use of a variety of synthesis blocks to create frequency synthesis systems with enhanced performance characteristics
Frequency synthesizers are used in a variety of communications and timing systems. Phase-locked loops (PLL) have been the "workhorse" of the majority of traditional synthesizers and clock generation circuits. However, there are other types of synthesis blocks available such as direct digital synthesizers (DDS), mixers, frequency doublers and dividers...
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A 2.4 GHz CMOS Power Amplifier with 20 dBm Output Power for Bluetooth and WLAN Applications

This article presents a 2.4 GHz CMOS power amplifier (PA) with an output power of 20 dBm using a 0.25 µm 1P5M standard CMOS process. The PA uses a diode connected NMOS transistor functioning as a diode linearizer. It is believed that this is the first ...
Due to the fast development of wireless communications, a low cost, high performance, high integration technology is needed for system on a chip (SOC) implementation. The CMOS technology provides a good solution for SOC integration. 1 Recent improvements of the standard CMOS process make it possible to implement RF...
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An RF Module Design for a Multi-mode Handset

This article describes a novel design of an RF module for a multi-mode handset and presents an example of an RF module for a W-CDMA/GSM/DCS tri-band and dual-mode handset. The entire module, including a direct modulation transmitter and a superheterody...
The number of mobile users is predicted to reach 1.7 billion by the year 2010. More than 45 percent of them will use high data speed services. W-CDMA, proposed by IMT2000, has become the most practical and important system for the development of new wireless communications. Nevertheless, second generation...
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Interactive Interdigital Filter Design Using MMICAD Software

Successful microwave circuit realization requires flexible circuit analysis tools that allow engineers to prototype, analyze and verify their circuits. Today, available software tools offer standard features such as frequency analysis, tuning and optimization, but are differentiated by their model libraries and special customization capabilities. This article describes the design...
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