This document discusses different modes for characterizing components under pulsed and modulated excitation using the ZVxPlus platform. It describes average pulse mode, which measures the average spectral response under pulsed excitation. Pulse profile mode allows measurement of all spectral components' amplitude and phase versus time. Modulation mode supports characterization under periodic signals like two-tone or noise modulation. These modes provide a full nonlinear characterization including fundamentals and harmonics under various excitation types.

1. ZVxPlus Technology
Update
- Pulse and Modulation -
May 2009

2. Outline
 Average Pulse Mode
 Pulse Profile Mode
 Modulation Mode
 Conclusion
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3. EPA120B-100P
 EPA120B-100P
• high efficiency heterojunction power FET
• power output: + 29.0dBm typ.
• power gain: 11.5dB typ. @ 12 GHz
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4. CW versus Pulse Mode
Pulsed Period: 500 us
CW Signal – 1 GHz Pulse width : 50 us
Amplitude drops
2kHz
Amplitude drops 20kHz
10kHz
2MHz
Pulsed Period: 100 us
Pulse width : 0.5 us
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5. Pulse Spectrum with VNA: selection of IF BW
IF BW Filter:
not sharp enough
IF Bandwidth < Tone spacing
IF BW filter must cut off sharply
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6. Average Pulse Mode
IF Bandwidth < Tone spacing
Only the main spectral component is measured
IF BW Filter: high selectivity
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7. ZVxPlus in Average Pulse Mode
10 MHz
Internal
Excitation
Source
Reflectometer
Receiver
Port 3
Synchroniser
Port 1 Port 2
20 dB
Spectrum
EPA Analyzer
External
Pulsed
RF Excitation
Proper selection of IF BW < Rep rate
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8. EPA120 in Pinch off under CW Stimulus
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9. EPA120 in Pinch off under Pulse Stimulus – Average Pulse Mode
Part of the information
Is missing ->
Amplitude of waveforms are
completely different
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10. Pulse Profiling Mode
1GHz, 2 GHz, 3GHz, ...
a1 a2
b1 b2
ZVA Pulse Profile Capabilities:
Measurement of all spectral components ● BW: up to 30 MHz
● in amplitude and phase ● Repetition rate: appr. 300 Hz
● for fundamental and harmonics
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11. Pulse Profile: Spectrum and Waveforms
40 Fundamental 20
40
60
Third Harm
Sec Harm MHz
60
30 20 10 10 20 30
MHz
30 20 10 10 20 30
100 100
a1 b2 120
Fundamental 0.2
0.015
0.01
0.1
0.005 Harmonics
2  10  7 4  10 7 6  10 7 8  10  7 1  10 6 2  10  7 4  10 7 6  10 7 8  10 7 1  10 6
0.005
0.1
0.01
0.015
0.2
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12. Modulation Mode: Spectrum and Waveforms
Two-tone – 1 kHz spacing
40
Fundamental 30 20 10
20
10 20 30
MHz
60 40
MHz 60
30 20 10 10 20 30 80
Sec Harm Third Harm 100
100
120
120 140
0.015
Fundamental
0.2
0.01
0.1
0.005
Harmonics
0.0002 0.0004 0.0006 0.0008 0.001 0.0002 0.0004 0.0006 0.0008 0.001
0.005
0.1
0.01
0.2
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13. Modulation Mode: Spectrum and Waveforms
Pseudo Random Noise – 5 MHz BW 10 kHz spacing 50 20
60
Fundamental 60
70 40
80
Sec Harm
60
0.1 0.05 0.05 0.1
100
7.5 5 2.5 2.5 5 7.5 110
7.5 5 2.5 2.5 5 7.5
120
100 100
120
120
140
140
Third Harm
0.3
0.025 Fundamental
0.25
0.02
0.2
0.015
0.15
0.01
0.1
0.005 Harmonics 0.05
0.00002 0.00004 0.00006 0.00008 0.0001
0.00002 0.00004 0.00006 0.00008 0.0001
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14. Conclusion
 The ZVxPlus allows to characterize the nonlinear behavior of components under
• Pulse excitation in average pulse mode
• Pulse excitation in pulse profile mode
• Periodic modulation in modulation mode
 The characterization includes fundamental and harmonics
For more information info@nmdg.be
www.nmdg.be
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