Copyright 2004 2006, Analog Devices, Inc. All rights reserved. Analog Devices assumes no responsibility for customer product design or the use or application of customers’ products or for any infringements of patents or rights of others which may result from Analog Devices assistance. All trademarks and logos are property of their respective holders. Information furnished by Analog Devices appl...

We present a new method of measuring the guided, radiated, and total decay rates in uniform waveguides. It is also shown theoretically that large modifications of the total decay rate can be achieved in realistic erbium-doped fiber amplifiers and erbium-doped waveguide amplifiers with effective mode area radii smaller than approximately 1 microm.

We review the nonlinear channel capacity of optical fiber communication systems using both linear and nonlinear amplifiers. We show that the capacity of a nonlinear transmission system employing linear optical amplifiers can be enhanced by over 300% by using all optical regeneration OCIS codes: 070.4340 Nonlinear optical signal processing, 190.4380 Four-wave mixing.

Modern communications require high linearity for power amplifiers. GaAs heterojunction bipolar transistor (HBT) based amplifiers are proven to have high efficiency, good linearity, ruggedness, and low cost. In this paper we report on an improved linearity GaAs HBT device achieved through a novel engineered Ft curve. The novelty of the solution relies on the flatness of the Ft curve with device ...

This paper presents a third-order Sigma-Delta modulator that uses only two operational amplifiers. A fully digital solution reduces both amplifiers output swings. This design achieves complex conjugate zeros that allows obtaining a signal-to-noise ratio of about 8 dB better than having all the zeros placed at z = 1. Behavioral level simulations demonstrate the effectiveness of the approach.

We report the first semiconductor optical amplifiers at 2.0-μm wavelength, heterogeneously integrated by bonding an InP-based active region to silicon. On-chip gain larger than 10 dB is observed at 20°C over a 40-nm bandwidth. OCIS codes: (130.3120) Integrated optics devices, (230.4480) Optical amplifiers.

In this paper the linearity performances of harmonic tuned microwave power amplifiers is discussed and analysed, inferring some useful design guidelines. By a simplified active device model, the effects of the amplifier harmonic loads on the intermodulation distortion are investigated and experimentally validated showing the IMD3 performances of four hybrid amplifiers, designed using different ...

The spectral frequency response, frequency response range, and volume control linearity of five telephone amplifiers were examined using real-ear measures. All measurements were performed in KEMAR's (Knowles Electronics Manikin for Acoustic Research) ear canal using a composite speech-shaped waveform as the stimulus. Spectral frequency response and response range of each device was obtained at ...

This paper reports two techniques for optimizing harmonic termination in power amplifiers. In the jirst technique, the active antenna approach, the antenna element acts as radiator and as part of the output tuning circuit. The second method, based on photonic band-gap (PBG) structure, incorporates a periodic harmonic tuning structure for microstrip lines. In this structure, a periodic 2-D patte...

MESSENGER's high-data-rate downlink will use the first electronically scanned phased-array antenna for a deepspace telecommunication application. Measured results for the lightweight phased-array antenna and the highefficiency Solid State Power Amplifiers (SSPAs), developed by JHU/APL, are presented. Two functional amplifiers within the X-band SSPAs provide output power that is scalable from 11...