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Search Publications by: Archita Hati (Fed)

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Displaying 76 - 90 of 90

Comparison of AM Noise in Commercial Amplifiers and Oscillators at X-Band

June 1, 2006
Author(s)
Archita Hati, David A. Howe, Craig W. Nelson
In this paper we discuss the importance of amplitude-modulated (AM) noise. AM noise is often neglected and considered a s a minor problem. However, AM noise can become very important in high performance systems that require ultra-low phase-modultaed (PM)

W-band dual channel AM/PM noise measurement system - an update

August 29, 2005
Author(s)
Archita Hati, Craig Nelson, J Nava, David A. Howe, Fred L. Walls, Huascar Ascarrunz, Justin Lanfranchi, Bill Riddle
We discuss the performance of a W-band (92-96) GHz amplitude modulated (AM) and phase modulated (PM) noise measurement system. The system uses two nearly identical channels to measure the residual noise in amplifiers in pulsed mode with a duty cycle of 10%

Low Phase Noise Amplifier and Oscillator Using Feed-Forward Technique at 10 GHz

June 1, 2005
Author(s)
Archita Hati, Craig W. Nelson, David A. Howe
We discuss the performance of a feed-forward amplifier (FFA) at 10GHz. The feed-forward method is primarily used to suppress intermodulation distortion in amplifiers to suppress up-converted near-DC noise. The main amplifier in this configuration is a low

W-band dual channel PM/AM noise measurement system

August 23, 2004
Author(s)
Archita Hati, Craig Nelson, J Nava, David A. Howe, Fred L. Walls
We discuss the performance of a W-band (92 to 96 GHz) PM and AM noise measurement system. The system uses two nearly identical channels to measure the AM or P M noise added by an amplifier or any passive component. It is principally designed to measure

High-Spectral-Purity Microwave Oscillator: Design Using Conventional Air-Dielectric Cavity

January 1, 2003
Author(s)
A Sen Gupta, David A. Howe, Craig Nelson, Archita Hati, F L. Walls, J F. Garcia nava
We report exceptionally low PM and AM noise levels from a microwave oscillator that uses a conventional air-dielectric cavity resonator as a frequency discriminator. Our approach is to increase the discriminator's intrinsic signal-to-noise ratio by use of

Noise Figure vs. PM Noise Measurements: A Study at Microwave Frequencies,

January 1, 2003
Author(s)
Archita Hati, David A. Howe, F L. Walls, D. Walker
This paper addresses two issues: (i) it compares the usefulness of phase-modulation (PM) noise measurements vs. noise figure (NF) measurements in characterizing the merit of an amplifier, and (ii) it reconciles a general misunderstanding in using -174 dBc

Parallel Configuration for Conjugate Regenerative Dividers

January 1, 2003
Author(s)
J F. Garcia nava, Archita Hati, Craig Nelson, A Sen Gupta, F L. Walls, T Tasset
In this paper we discuss an alternate design of a self-starting conjugate regenerative divider (CRD), which uses two parallel loops instead of one series loop as in conventional regenerative divider. This is accomplished by making the first loop oscillate

A 100 GHz AM and PM Noise Measurement System: Preliminary Design and Performance

January 1, 2002
Author(s)
David A. Howe, Craig W. Nelson, F L. Walls, J F. Garcia nava, Archita Hati, A Sen Gupta
A 1OO GHz AM and PM noise measurement system is described. The basic approach to its construction is to apply existing state-of-the-art, cross-correlation noise measurement techniques to 1OO GHz (W-band).

Wide-Range Microwave Frequency Synthesis Using An Offset Passive Resonator

January 1, 2002
Author(s)
David A. Howe, Archita Hati, Craig W. Nelson, F L. Walls, J F. Garcia nava, A Sen Gupta
We demonstrate a technique to obtain wide synthesized tunability from the local oscillator (LO) of a low-noise, fixed-frequency microwave reference whose noise is suppressed by a high-Q cavity discriminator operated in a passive mode. The results show that