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Search Publications by: Dazhen Gu (Fed)

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Displaying 26 - 50 of 142

Noise-Synthesis Technique in Time~Domain for Metrology Application

May 11, 2019
Author(s)
Dazhen Gu, Jeffrey E. Jenkins
We developed a prototype radiometer system to implement the noise-synthesis technique. A solid- state switch synthesizes noise signals from outputs of two synchronized electromechanical switches. The input ports of electromechanical switches are terminated

A Self-Calibrated Transfer Standard for Microwave Calorimetry

July 8, 2018
Author(s)
Dazhen Gu, Xifeng Lu, Ben Jamroz, Dylan Williams, Billy F. Riddle, Xiaohai Cui
We develop a new calibration technique for measuring the correction factor of a calorimeter with a vector network analyzer. Based on a wave-parameter formulation, we develop analytic formulas for the correction-factor ($g$) and effective-efficiency ($\eta$

Thermal Noise Metrology with Time-Based Synthesis

July 8, 2018
Author(s)
Dazhen Gu
We present a new measurement technique of quantifying noise temperature based on temperature and time. A single pole double throw (SPDT) ultra-fast switch combines signal from outputs of two synchronized electromechanical (EM) switches. The input ports of

G-band Reflectivity Results of Conical Blackbody for Radiometer Calibration

January 14, 2018
Author(s)
Derek A. Houtz, Dazhen Gu
Two hollow conical cavities have been developed and built for the National Institute of Standards and Technology (NIST) for use as radiometric brightness temperature sources, or blackbodies. According to Kirchoff's reciprocity relation, a good absorber is

Black Box Measurement of System Noise in Integrated Wireless Receivers

September 13, 2017
Author(s)
Daniel G. Kuester, Duncan A. McGillivray, Sheryl M. Genco, Dazhen Gu
Tightly-integrated antennas and inaccessible radio frequency (RF) outputs are common barriers to measuring system noise in integrated wireless receive systems. We propose a solution centered on locating "SNR isoresponses" --- processed receiver outputs

Efficient Rectangular Waveguide to Stripline Transition in D Band

August 7, 2017
Author(s)
Dazhen Gu, Xifeng Lu, Ronald A. Ginley
We present a waveguide-to-stripline transition for a full {\it D}-band operation from 110 GHz to 170 GHz. An E-plane probe in parallel with waveguide main axis is configured to effectively couple the signal in the primary $\text{TE}_{10}$ mode from the

Vector-Network-Analyzer Calibration Using Line and Multiple Coplanar-Waveguide Offset Reflects

December 9, 2016
Author(s)
Arkadiusz C. Lewandowski, Wojciech Wiatr, Dazhen Gu, Nate Orloff, Thomas Mitchell (Mitch) Wallis, Pavel Kabos
We present the application of our newly developed multi-reflect-thru technique to vector-network-analyzer calibration in the on-wafer environment. This technique uses a set of highly-reflective one-port devices, referred to as offset-reflects, and a single