Phase Noise and Noise Measurement

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Phase Noise and Noise Measurement

• Pengcheng Jia
• Nov 21, 2002

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• Phase Noise

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Sth New

• Phase Noise Measurement with PSA (precision
  spectrum analyzer)
• Mode-gtPhase Noise-gtLogPlot
• But pay attention to noise floor of the PSA. You
  can use noise floor cancellation function or use
  the HP11848 Phase noise system

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Phase Noise Origins

• 1/f Noise of Semiconductor Transistor
• DC Bias related noise (Shot Noise)
• Thermal Noise from Resistors

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Phase Noise Basic
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Residual Noise Measurement
20 dB Attenuator
11848 Phase Noise Interface
8dBm
R Port
L Port
10dBm
GPIB Control

0.01Hz 100KHz
3561A Dynamic Signal Analyzer

• Phase shifter is used to achieve quadrature
• Attenuator is used to keep input power at
  required level
• Phase noise of source will not affect residual
  noise of DUT when quadrature is achieved

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3048 System
11729
11848
3561
Spectrum Analyzer
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Phase Noise Measurements
Phase Noise without amplifiers
Phase noise of a broadband amplifier
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3048A Phase Noise Software

• Tiger is the 3048A system controller
• Start in MS-Dos Mode
• At the command prompt, enter c\go
• Select 13 as the printer type and 0 as the screen
  mode. The other settings are user preference
• Now you are at c\noise\3048gt
• Run cal.exe for calibration and PN.exe for
  measurement

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Instrument Addresses

• Run PN.exe, Main Menu-gtSystem-gtInstrument
• Instrument Model Address
• FFT Analyzer 3561A 712
• RF Analyzer 8567A 718 (optional for offset from
  100K to 40MHz)
• Signal Srce 1
• Signal Srce 2
• Down Converter 11729C 706 (optional)

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Getting system ready

• Functional Checks
• Quick Check
• Performance checks
• Calibrations
• Read appendix for the time and sequence of
  calibration

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Run PN.exe

• 1.Type of measurement-gtPhase noise without using
  PLL (for residual phase noise measurement)
• Start/Stop frequency are the offset frequency
  from the carrier
• 2. Parameters
• Input carrier frequency and select detector

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Continue

• Instrument control
• Select system connections
• Define graph
• Configure the displayed graph
• System configuration-gtInstruments
  addresses-gtInput addresses

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File System

• Test file Directory
• Save all the configurations for the measurement
• Result file directory
• Save the measurement result in this directory
• Always choose this directory before you save
  your result, otherwise you only save the
  configurations, not the data!!!
• Run Read_res.exe to convert .res file to data
  file which can be used in graph tools.
• Go to mishrayork web-gtdocument for the file.

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Calibration-theory
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Calibration-operation

• For the first time, run calibration
• Select Derive from measured beat tone
• -gtexit to main menu-gtNew measurement
  -gtY-gtSelect 1KHz as beat-tone (range from 1Hz
  to 50KHz), input the beat tone signals to the R
  and L input of the 11848 interface-gtProceed-gtget
  detector constant
• Then change connection back and measure PN
• Next time, go to calibration-gtuse current
  detector constant

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Measurement

• Pay attention to the right and left channel power
  level
• For frequency 1.2 G to 18G
• L 7-gt10dBm
• R 0-gt10dBm
• Keep R channel close to 10dBm, the higher R
  signal, the lower noise floor

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• Noise Figure

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Measurement System
Noise Figure Meter-8970B
Noise Source Driver
CW Generator-8673G Output power-8dBm
Noise Source - 346C
Noise Input
LO Signal Input
Test Set-8971B Working ModeSSB3 From
4-18GHz Down Convert to 450MHz Single Side Band
Noise
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Single MMIC Measurement
Bias For MMIC
Microstrip Probe
Noise Output
Noise Input
MMIC
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Combiner Measurement
Bias For MMICs
Noise Source Driver Input
Noise Input
Noise Source
Noise Output
Power Combiner
Heat Sink
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Measurement Theory

• The Noise Figure Meter output noise at two
  different noise temperature
• Get the G and Na from the measurement
• Calibrate to eliminate the affect of the loss of
  the cable and connectors

Output Noise Power No
N2
N1
Na
Noise Temperature-T
T1
T2
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Measurement Result