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Search Publications by: Craig Nelson (Fed)

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Displaying 76 - 100 of 106

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)

Impedance Control for Critically Coupled Cavities

August 31, 2005
Author(s)
Billy F. Riddle, Craig Nelson
Cavity resonators are often used in low phase noise oscillators that utilize carrier suppression. These oscillators are employed in systems that measure phase noise in frequencies as hight at 100 GHz. In order to achieve the maximum suppression needed in

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

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

Microwave Synthesizers for Atomic Frequency Standards

January 1, 2001
Author(s)
A Sen gupta, F Garcia nava, Craig Nelson, David A. Howe, F L. Walls
Following our earlier work on a new approach to synthesising the Cs hyperfine frequency of 9.192 GHz, we describe developments on its further refinements. The salient feature of our design is that it is based mainly on frequency division and requires no