Large-Signal Network Analysis Technology to help the R&D Customer
description
Transcript of Large-Signal Network Analysis Technology to help the R&D Customer
Large-Signal Network Analysis Tools and Techniques Page 1
Large-Signal Network Analysis
Technologyto help the R&D Customer
Large-Signal Network Analysis Tools and Techniques Page 2
Agenda
Introduction Large-Signal Network Analysis The Large-Signal Network Analyzer Calibration The core of the LSNA Technology Examples A typical LSNA measurement session Next steps in LSNA Technology Wrap-up
Large-Signal Network Analysis Tools and Techniques Page 3
Design Challenge
“Customers are demanding more capabilities/performance from their devices.”
Designers are looking for better methods of characterizing their components
Demands translate to greater design complexities
More complex modulation schemes
Higher power efficiency requirements
Improved linearity
90
0 PhaseSplitter
I/Q Modulator
LO
I
Q
Rx/TxModule
MCPA
PA Module
Matched Transistors
Mixer
Transistors
ProcessEngineer
PADesigner
ModelingDesigner
ICDesigner
SystemDesigner
Large-Signal Network Analysis Tools and Techniques Page 4
Why can’t I predict device behavior
To be successful in this environment, it is essential to fully characterize and understand device behavior
Need more realistic test conditions Devices that operate in large-signal environments
can’t be characterized with linear tools
Existing tools are insufficient Network analyzers only characterize small-signals (linear) behavior accurately Signal analyzers evaluate properties of signals interacting with the test device,
they do not analyze the interactions of analyzer with the test device
Large-Signal Network Analysis Tools and Techniques Page 5
AM-PM
Amplifier Measurements
Device UnderTest
Loadpull
ACPR
GainPower in and out
Power Added Efficiency
Phase flatness
Large-Signal Network Analysis Tools and Techniques Page 6
Build two MCPAs, one passes the other does not Do you know what to fix?
ACPR and other measurement data only represent symptoms of the problem No insight is provided as to the cause of the problem
ACPR of an MCPA
FAIL
PASS
Large-Signal Network Analysis Tools and Techniques Page 7
Existing Measurements and Limitations
Spectral re-growth, IMD, ACPR
Characterizes signals caused by nonlinear behavior of components - in the frequency domain
EVM
Compares deviation of modulated signal from ideal - in the time domain
Limitations
Characterizes signals resulting from interaction DUT - measurement system, device performance is not isolated
Results will change when environment changes Different sources and analyzers can produce different results Characterizing just the DUT requires perfectly matched conditions
DUT Freq. (GHz)DUTZ1 Z2
Large-Signal Network Analysis Tools and Techniques Page 8
Existing Measurements and Limitations con’t
AM-AM and AM-PM
Characterizes changes in output power and phase with changes in input power Starts defining the transfer function of the nonlinear behavior
Limitations
DUT performance is still not isolated from the rest of the system
Results will change with changes in the environment
Results also depend on type of test signal regardless of matched conditions
DUT Freq. (GHz)DUTZ1 Z2
Large-Signal Network Analysis Tools and Techniques Page 9
Existing Measurements and Limitations con’t
Load Pull
Traditional: Characterizes applied impedances and powers at fundamental frequency Measures incident, reflected and transmitted power as a function of S and L
Harmonic: Characterizes applied impedances and powers at fundamental and harmonics
Provides more complete information than traditional load pull. Harmonic termination has large impact on performance
Limitations
Information is still missing, the DUT is not completely characterized
Does not allow to apply PA design theory (waveform engineering)
Measurements do not uniquely define a particular test state
May identify multiple local minimums as opposed to a optimal (global) minimum
DUTSourceTuner(S )
LoadTuner(s)
(L )
x x x x
VNA, SAor Pwr Mtr.
VNA, SAor Pwr Mtr.
Large-Signal Network Analysis Tools and Techniques Page 10
Existing Measurements and Limitations con’t
Modulated S-parameters
Attempt to use known concepts in new situations
Hot S22
Characterizes the interaction of the DUT with the load under large - signal drive Depends on the chosen configuration
Limitations
Modulated S-parameters do not have a scientific basis Superposition principles do not apply for nonlinear behavior Results will vary with the test conditions when device is nonlinear
Hot S22 is still missing critical information for complete nonlinear characterization
The missing data mayor may not impact measurement results
Large-Signal Network Analysis Tools and Techniques Page 11
Insufficient Modeling Tools
Ideal:
Measurements correlate with simulationsIn a linear environment, S-Parameters are an excellent example
The real world for non-linear characterization:
Insufficient models Incomplete informationPoor correlation between measurements and simulations
Model Simulate Build Meas S-PACPR
Power=
Model Simulate Build Meas
Large-Signal Network Analysis Tools and Techniques Page 12
Results
Cut-and-try engineering (designers “imagineer” fixes) Design verification consumes 2/3rds of development time Time-to-market delays Unpredictable design processes Time consuming tuning and measurement requirements
Large-Signal Network Analysis Tools and Techniques Page 13
How can Agilent help?
Large - Signal Network Analysis is a breakthrough new technology that provides unprecedented insight into transistor, component and system behavior using the same concepts across this complete spectrum
Through a small dedicated team Agilent is ready to work closely with early-adopter customers in different markets to create successes in their R&D environment through this technology
Large-Signal Network Analysis Tools and Techniques Page 14
Agenda
Introduction Large-Signal Network Analysis The Large-Signal Network Analyzer Calibration The core of the LSNA Technology Examples A typical LSNA measurement session Next steps in LSNA Technology Wrap-up
Large-Signal Network Analysis Tools and Techniques Page 15
Large - Signal Network Analyzer (LSNA) Technology Goals
complete characterization of a device, component and system under large - signal periodic stimulus at its ports. LSNA technology is presently limited to devices that maintain periodicity in their response
deriving nonlinear component characteristics which are invariant for the used equiment and test signals
Foundation: Large-signal Network Analysis
Large-Signal Network Analysis Tools and Techniques Page 16
Small-Signal Network Analysis
Small-Signal Linear Behavior Test signal : simple, typically a sine wave Superposition principle to analyze behavior in realistic conditions
Network Transistor, RFIC, Basestation Amplifier, Communication system
Analysis Complete component characterization : S - parameters
(within measurement bandwidth)
Large-Signal Network Analysis Tools and Techniques Page 17
Large-Signal Network Analysis
Large-Signal Refers to potential nonlinear behavior Nonlinear behavior -> Superposition is not valid Requirement: Put a DUT in realistic large-signal operating conditions
Network Transistor, RFIC, Basestation Amplifier, Communication system
Analysis Characterize completely and accurately the DUT behavior for a given type of stimulus Analyze the network behavior using these measurements
Large-Signal Network Analysis Tools and Techniques Page 18
Large-Signal Network Analysis: Overview
TransistorRFICSystem
RealisticStimulus
RealisticStimulus
Measurement System
1v
1i2v
2i1a
1b
2a
2b
0)|,,,,(
0)|,,,,(
2121
2121
ftiivvg
ftiivvf Physical Quantity Sets
Travelling Waves (A, B)
Voltage/Current (V, I)
Representation Domain Frequency (f)
Time (t)
Freq - time (envelope)
Analysis
Large-Signal Network Analysis Tools and Techniques Page 19
Practical Limitations of LSNA for Large-Signal Network Analysis
Large-Signal Network analysis will be performed using periodic stimuli
one - tone and harmonics periodic modulation and harmonics
The devices under test maintain periodicity in their response
Large-Signal Network Analysis Tools and Techniques Page 20
Continuos Wave Signal
Freq. (GHz)
1 2 3 4DC
DUT
Z1
Z2
Freq. (GHz)
1 2 3 4DC
Freq. (GHz)
1 2 3 4DC
Freq. (GHz)
1 2 3 4DC
Freq. (GHz)
1 2 3 4DC
All voltages and currents or waves are represented by a fundamental and harmonics (including DC)
Complex Fourier coefficients Xh of waveforms
X0
X1
X2
X3
X4
Large-Signal Network Analysis Tools and Techniques Page 21
Amplitude and Phase Modulation of Continuos Wave Signal
Freq. (GHz)
1 2 3 4DC
DUTZ1 Z2
Freq. (GHz)
1 2 3 4DC
Freq. (GHz)
1 2 3 4DC
Freq. (GHz)
1 2 3 4DC
Freq. (GHz)
1 2 3 4DC
Complex Fourier coefficients Xh(t) of waveforms
Phasor
Amplitude
Phase
Fast change (GHz)
Slow change (MHz)
Modulation
X0(t)
X1(t)
X2(t)
X3(t)
X4(t)
time
time time
time time
Large-Signal Network Analysis Tools and Techniques Page 22
Periodic Modulated Signals
Freq. (GHz)
1 2 3 4DC
DUT
Z1
Z2
Freq. (GHz)
1 2 3DC
Complex Fourier coefficients Xhm of waveforms
Freq. (GHz)
1 2 3DC
Freq. (GHz)
1 2 3DC
Freq. (GHz)
1 2 3DC
Phasor
Amplitude
Phase
PeriodicModulation
X0i
X1i
X2i X3i
Large-Signal Network Analysis Tools and Techniques Page 23
Waves (A, B) versus Current/Voltage (V, I)
50cZTypically
2
IZVA c
2
IZVB c
BAV
cZ
BAI
“From device to system level”
Large-Signal Network Analysis Tools and Techniques Page 24
Small-Signal Network Analysis: S-parameters
2221212
2121111
aSaSb
aSaSb
TransistorRFICSystem
Measurement System
1a
1b
Analysis
sexperimentdifferent ngrepresenti with
,,, 2211
i
baba iiii
2a
2b
50
Experiment 1
TransistorRFICSystem
Measurement System
1a
1b2a
2b
50
Experiment 2
Large-Signal Network Analysis Tools and Techniques Page 25
Large-Signal Network Analysis
TransistorRFICSystem
RealisticStimulus
RealisticStimulus
Measurement System
1v
1i2v
2i1a
1b
2a
2b
0)|,,,,(
0)|,,,,(
2121
2121
ftiivvg
ftiivvf Analysis
sexperimentdifferent ngrepresenti with
,,, 2211
i
baba iiii
Different Experiments
Large-Signal Network Analysis Tools and Techniques Page 26
Agenda
Introduction Large-Signal Network Analysis The Large-Signal Network Analyzer Calibration The core of the LSNA Technology Examples A typical LSNA measurement session Next steps in LSNA Technology Wrap-up
Large-Signal Network Analysis Tools and Techniques Page 27
Vector Network Analyzer Measurement
50 Ohm
Acquisition
Calibration
Linear Theory
S-parameters
Stimulus
Response
ReferencePlanes
H
MEAS FORMATSCALE
REF
DISPLAY AVG CAL
MKRFCTN
MKR
CH 1 CH 2
MENU
START STOP
CENTER SPAN
SYSTEM LOCALUSER
PRESET
COPYSAVE
RECALL SEQ
7 8 9
4 5 6
1 2 3
0 . -
@
n
M
k
m
x1ENTRY
OFF
ACTIVE CHANNEL
RESPONSE
STIMULUS
ENTRY
INSTRUMENT STATE R CHANNEL
OUTR L T S
HP-IB STATUS
IN
PROBE POWER FUSED
PORT 1 PORT 2
TRANS FWDREFL FWD
TRANS REVREFL REV
+26 dBm RF 30 VDC MAX PORTS 1&2 AVOID STATIC DISHCARGE
8753DNETWORK ANALYZER
30 KHz-3GHz
Large-Signal Network Analysis Tools and Techniques Page 28
Complete SpectrumWaveforms
Harmonics and Periodic Modulation
50 Ohmor
tuner
Acquisition
Calibration
Stimulus
Response
ReferencePlanes
ModulationSource
Large-Signal Network Analyzer
Large-Signal Network Analysis Tools and Techniques Page 29
Filter
Filter
Filter
FilterDUT
TestSet
Data
-Acq
uisit
ion
LO
Source
2nd Source
PC
Sampling Converter
Cal Kit
Power Std
Phase Std
LSNA System Block Diagram
Calibration Standards
Converts carrier, harmonics
and modulationto IF bandwidth
Separates incident andreflected waves intofour meas. channels
Or Tuner
On waferConnectorized
•RF bandwidth: 600 Mhz - 20 GHz•max RF power: 10 Watt•Modulation bandwidth•Needs periodic modulation
E1430 - based4 MHz IF
10 MHz IF
Large-Signal Network Analysis Tools and Techniques Page 30
Harmonic Sampling - Signal Class: CW
Freq. (GHz)1 2 3
50 fLO 100 fLO 150 fLO
Freq. (MHz)1 2 3
RF
IF
fLO=19.98 MHz = (1GHz-1MHz)/50
LP IF Bandwidth: 4 MHz
Cutt Off IF
Large-Signal Network Analysis Tools and Techniques Page 31
Harmonic Sampling - Signal Class: Periodic Modulation LP
IF Bandwidth: 4 MHz
1 2 3
50 fLO 100 fLO 150 fLO
Freq. (MHz)1 2 3
RF
IF
fLO=19.98 MHz = (1GHz-1MHz)/50
Large-Signal Network Analysis Tools and Techniques Page 32
Harmonic Sampling - Signal Class: Periodic Broadband Modulation
Freq. (GHz)1 2 3
150 fLO
Freq. (MHz)
RF
IF
LP
BW
BW
Adapted sampling process
BW of Periodic Broadband Modulation = 2* BW IF data acquisition
BW8 MHz
Large-Signal Network Analysis Tools and Techniques Page 33
Agenda
Introduction Large-Signal Network Analysis The Large-Signal Network Analyzer Calibration The core of the LSNA Technology Examples A typical LSNA measurement session Next steps in LSNA Technology Wrap-up
Large-Signal Network Analysis Tools and Techniques Page 34
50 Ohmor
tuner
Acquisition
Calibration
Stimulus
Response
ReferencePlanes
ModulationSource
LSNA Calibration
Measured waves
Actual waves at DUT
7 relative error termssame as a VNAAbsolute magnitude
and phase error term
ma1mb1
ma2mb2
DUTa1DUTa2
DUTb1
DUTb2
m
m
m
m
DUT
DUT
DUT
DUT
b
a
b
a
K
b
a
b
a
2
2
1
1
22
22
11
1
2
2
1
1
00
00
00
001
F0=1GHz
freq
1GH
z
2GH
z
3GH
z
Large-Signal Network Analysis Tools and Techniques Page 35
Relative Calibration: Load-Open-Short
50 Ohm
Acquisition
50 Ohm
LoadOpenShort
50 Ohm
Acquisition
50 Ohm Thru
{f0, 2 f0, …, n f0}
Calibration for fundamental and Harmonics
22
22
11
1
00
00
00
001
K
{f0, 2 f0, …, n f0}
F0=1GHz
Large-Signal Network Analysis Tools and Techniques Page 36
Power Calibration
50 Ohm
Acquisition
Power Meter
{f0, 2 f0, …, n f0}
22
22
11
1
00
00
00
001
K
Amplitude
{f0, 2 f0, …, n f0}
F0=1GHz
freq
2GH
z
3GH
z
1GH
z
Large-Signal Network Analysis Tools and Techniques Page 37
Phase Calibration
50 Ohm
Acquisition
Reference Impulse Generator
f0
...f0
50 Ohm
22
22
11
1
00
00
00
001
K
Phase
{f0, 2 f0, …, n f0}freq
2GH
z
3GH
z
1GH
z
F0=1GHz
Large-Signal Network Analysis Tools and Techniques Page 38
Measurement Traceability
Relative Cal Phase Cal Power Cal
National Standards(NIST)
Agilent Nose-to-Nose Standard
Large-Signal Network Analysis Tools and Techniques Page 39
Agenda
Introduction Large-Signal Network Analysis The Large-Signal Network Analyzer Calibration The core of the LSNA Technology Examples A typical LSNA measurement session Next steps in LSNA Technology Wrap-up
Large-Signal Network Analysis Tools and Techniques Page 40
The heart of the Large-Signal Network Analysis
This hardware is the core that will be used to work with the customer in providing LSNA technology
Combines capabilities of a vector network analyzer, sampling scope and ESG-VSA.
Provides complete waveform analysis capabilities CW/Multi-tones with harmonics 0.6 to 20 GHz frequency coverage 8MHz usable IF BW 10 W power handling capability
Large-Signal Network Analysis Tools and Techniques Page 41
Agenda
Introduction Large-Signal Network Analysis The Large-Signal Network Analyzer Calibration The core of the LSNA Technology Examples A typical LSNA measurement session Next steps in LSNA Technology Wrap-up
Large-Signal Network Analysis Tools and Techniques Page 42
Examples
Transistor reliability Transistor model verification (ICCAP / ADS) Transistor model tuning PA design using waveform engineering System level characterization Scattering functions Memory effect Dynamic bias
Large-Signal Network Analysis Tools and Techniques Page 43
Gate - Drain Breakdown Current
Time (ns)
º transistor provided by David Root, Agilent Technologies - MWTC
º TELEMIC / KUL
Large-Signal Network Analysis Tools and Techniques Page 44
Forward Gate Conductance
Time (ns)
º transistor provided by David Root, Agilent Technologies - MWTC
º TELEMIC / KUL
Large-Signal Network Analysis Tools and Techniques Page 45
Examples
Transistor reliability Transistor model verification (ICCAP / ADS) Transistor model tuning PA design using waveform engineering System level characterization Scattering functions Memory effect Dynamic bias
Large-Signal Network Analysis Tools and Techniques Page 46
Use of LSNA measurements in ICCAP model verification, optimisation (and extraction)
ICCAP specific input
ADS netlist. Used, a.o., to impose themeasured impedance to the output ofthe transistor in simulation
sweep of Power Vgs Vds Freq
Large-Signal Network Analysis Tools and Techniques Page 47
Transistor De-embedding
0 0.5 1 1.5 2
- 3
- 2
- 1
0
1
2 beforeafter
de-embedding
Time/period
Gat
e cu
rrent
/ m
A
Equivalent circuit of the RF test-structure, including the DUT and layout parasitics
Large-Signal Network Analysis Tools and Techniques Page 48
Input capacitance behaviourVgs,dc=0.9 VVds,dc=0.3 V Vds,dc=1.8 V
Input loci turn clockwise, conform i=C*dv/dt
Large-Signal Network Analysis Tools and Techniques Page 49
Dynamic loadline & transfer characteristicVgs,dc=0.3 VVds,dc=0.9 V
Large-Signal Network Analysis Tools and Techniques Page 50
LSNA identifies modeling problem : extrapolation example SiGe HBT
100 200 300 400 500 600 700 8000 900
-0.002
-0.001
0.000
0.001
-0.003
0.002
time, psec
i1st
si1
mts
_de
100 200 300 400 500 600 700 8000 900
0.6
0.7
0.8
0.9
1.0
1.1
0.5
1.2
time, psec
v1
sts
v1
mts
_de
100 200 300 400 500 600 700 8000 900
1.3
1.4
1.5
1.6
1.2
1.7
time, psec
v2
sts
v2
mts
_de
100 200 300 400 500 600 700 8000 900
0.000
0.002
0.004
0.006
-0.002
0.008
time, psec
i2st
si2
mts
_de
SiGe HBT (model parameters extracted using DC measurements up to 1V) Vbe= 0.9 V; Vce=1.5 V; Pin= - 6 dBm; f0= 2.4 GHz
simul.meas.
Large-Signal Network Analysis Tools and Techniques Page 51
LSNA identifies modeling problem : extrapolation example SiGe HBT
Measurement Simulation
SiGe HBT - DC characteristics
0.2 0.4 0.6 0.8 1.0 1.2 1.40.0 1.6
-0.010
-0.005
0.000
0.005
0.010
0.015
0.020
-0.015
0.025
VbDC
DC
meas1
..Ic
e
0.2 0.4 0.6 0.8 1.0 1.2 1.40.0 1.6
-0.010
-0.005
0.000
0.005
0.010
0.015
0.020
-0.015
0.025
VbDC
i2.i
Alcatel Microelectronics and the Alcatel SELStuttgart Research Center teams are acknowledged
for providing these data.
Large-Signal Network Analysis Tools and Techniques Page 52
Examples
Transistor reliability Transistor model verification (ICCAP / ADS) Transistor model tuning PA design using waveform engineering System level characterization Scattering functions Memory effect Dynamic bias
Large-Signal Network Analysis Tools and Techniques Page 53
MODEL TO BE OPTIMIZED
generators apply LSNA measured waveforms
“Chalmers Model”
“Power swept measurements under mismatched conditions”
GaAs pseudomorphic HEMTgate l=0.2 um w=100 um
Parameter Boundaries
Empirical Model Tuning
º Dominique Schreurs, IMEC & KUL-TELEMIC
Large-Signal Network Analysis Tools and Techniques Page 54
During OPTIMIZATION
Time domain waveforms Frequency domain
gate drain
voltage
current
gate drain
Voltage - Current State Space
Using the Built-in Optimizer
Large-Signal Network Analysis Tools and Techniques Page 55
Verification of the Optimized Model
Time domain waveforms Frequency domain
gate drain
voltage
current
gate drain
Voltage - Current State SpaceAFTER OPTIMIZATION
Large-Signal Network Analysis Tools and Techniques Page 56
Examples
Transistor reliability Transistor model verification (ICCAP / ADS) Transistor model tuning PA design using waveform engineering System level characterization Scattering functions Memory effect Dynamic bias
Large-Signal Network Analysis Tools and Techniques Page 57
Waveform Engineering Block Diagram
DUTTestSet Da
ta-A
cqui
sitio
n
Source
PC
Sampling Converter
Filter
Filter
Filter
Filter
LO
f0
f0
2f0
3f0IRCOM Setup
Large-Signal Network Analysis Tools and Techniques Page 58
Example - Measured Waveforms
MesFET Class Ff0=1.8 GHzIds0=7 mAVds0= 6 V
Z(f0)=130+j73 Z(2f0)=1-j2.8 Z(3f0)=20-j97
PAE=84%
PAE50%
WaveformEngineering
º IRCOM / Limoges
Large-Signal Network Analysis Tools and Techniques Page 59
Example - Performance ImprovementDerived Information from the V/I waveforms (swept input power at different terminations)
Z(f0)=123+j72 Z(2f0)=50 Z(3f0)=50
Z(f0)=123+j72 Z(2f0)=2 - j 4.0 Z(3f0)=50
Z(f0)=123+j72 Z(2f0)=2 - j 4.0 Z(3f0)=21-96
PAE74%
PAE74%
PAE84%º IRCOM / Limoges
Large-Signal Network Analysis Tools and Techniques Page 60
Examples
Transistor reliability Transistor model verification (ICCAP / ADS) Transistor model tuning PA design using waveform engineering System level characterization Scattering functions Memory effect Dynamic bias
Large-Signal Network Analysis Tools and Techniques Page 61
RFIC Amplifier Characterization using periodic modulation
ModulationSource
a1
E1
a1
E1
A1 shows spectral regrowth
• Spectral regrowth on b1 combined with measurement system mismatch• Nonlinear pulling on source
5 dB
f0 = 1.9 GHz Evaluation Board
Large-Signal Network Analysis Tools and Techniques Page 62
Transmission Characteristics
A1
Carrier Modulation
Carrier Modulation
B2
Carrier Modulation
3rd harmonicModulation
Harmonic DistortionCompression
Large-Signal Network Analysis Tools and Techniques Page 63
Reflection Characteristics
A1
Carrier Modulation
Carrier Modulation
B1
3rd harmonicModulation
Harmonic Distortion
Carrier Modulation
2nd harmonicModulation
Expansion
Large-Signal Network Analysis Tools and Techniques Page 64
Examples
Transistor reliability Transistor model verification (ICCAP / ADS) Transistor model tuning PA design using waveform engineering System level characterization Scattering functions Memory effect Dynamic bias
Large-Signal Network Analysis Tools and Techniques Page 65
Scattering Functions provide device understanding and enable CAE couplingTuners and active injection at harmonics
@ fundamental frequency
@ higher harmonics
Large-Signal Network Analysis Tools and Techniques Page 66
Nonlinear behaviour and Scattering Functions
Nj
iijphijijphijphphphph aHaGaHaGaFb
,...,22,1
**2121212111
Functions of 11a
Index of: Port & harmonicNote: a’s and b’s are phase normalized quantities !!
As shown before: for small-signal levels (linear) this reduces to (fundamental at port 2)nnnnnn aSaSb 2122112121
(and independent bias settings)
Large-Signal Network Analysis Tools and Techniques Page 67
Scattering functionsvariation versus input power
- 20 - 15 - 10 - 5 5
- 50
- 40
- 30
- 20
- 10
10
20
- 20 - 15 - 10 - 5 5
- 100
- 50
50
100
21F
2121G
2121H
21F
2121G
2121H
Large-Signal Network Analysis Tools and Techniques Page 68
Generated reflection coefficients at port 2 at f0
Generated ’s
’s for verification meas.
21(a)
Large-Signal Network Analysis Tools and Techniques Page 69
Time domain waveformsmeasured and simulated b-waves
200 400 600 800 1000
- 0.2
- 0.1
0.1
0.2
200 400 600 800 1000
- 6
- 4
- 2
2
4
6 tb1
tb2
Large-Signal Network Analysis Tools and Techniques Page 70
Application of CDMA-like signal
- 25 - 20 - 15 - 10 - 5 5
5
10
15
20
25
Output power versus input power; CW HredL, CDMA HlinesL
Large-Signal Network Analysis Tools and Techniques Page 71
20 40 60 80 100 120 140
- 60
- 40
- 20
21bFrequency domain
fc=2.45 GHz, f 50 kHz, modulation BW 1.45 MHz
red=measured, blue=model
Large-Signal Network Analysis Tools and Techniques Page 72
Examples
Transistor reliability Transistor model verification (ICCAP / ADS) Transistor model tuning PA design using waveform engineering System level characterization Scattering functions Memory effect Dynamic bias
Large-Signal Network Analysis Tools and Techniques Page 73
Time domain
,,,,, '22
'112 tatatataftb m
250 300 350 400 450 500
2
3
4
5
6
tb m2Memory effects !
Large-Signal Network Analysis Tools and Techniques Page 74
Memory effectsDUT behaviour under 2-Tone excitation
-8 -6 -4 -2 0 2 4
14
16
18
20
22
24
26
-8 -6 -4 -2 0 2 4
14
16
18
20
22
24
26
Modulation frequency = 20 kHz Modulation frequency = 620 kHz
Large-Signal Network Analysis Tools and Techniques Page 75
Examples
Transistor reliability Transistor model verification (ICCAP / ADS) Transistor model tuning PA design using waveform engineering System level characterization Scattering functions Memory effect Dynamic bias
Large-Signal Network Analysis Tools and Techniques Page 76
What is “Dynamic Bias Behaviour”?
Freq. (GHz)
1 2DCFreq. (GHz)
1DC
Input Voltage Output Current
1V 2I
Dynamic Bias Behaviour
Frequency Domain: Generation of Low Frequency Intermodulation Products
Time Domain:“Beating” of the Bias
Large-Signal Network Analysis Tools and Techniques Page 77
Dynamic Bias: Measurement Principle
TUNER
RF Data Acquisition
Dynamic Bias Data Acquisition
CurrentProbe
Bias 1Supply
CurrentProbe
Bias 2Supply
Computer
Large-Signal Network Analysis Tools and Techniques Page 78
0 0.2 0.4 0.6 0.8 1 1.2
0
20
40
60
0 0.2 0.4 0.6 0.8 1 1.2-2
-1.5
-1
-0.5
0
0.5
RFIC Example in Time Domain
00.20.40.60.811.2-2-1.5-1-0.500.5
Output Current Waveform (without Dynamic Bias)
(mA)
(V)
Normalized Time
Normalized Time
Input Voltage Waveform
“MultiLine TRL”
Large-Signal Network Analysis Tools and Techniques Page 79
0 0.2 0.4 0.6 0.8 1 1.2
25
30
35
40
45
Adding Measured Dynamic Bias
00.20.40.60.811.2-2-1.5-1-0.500.5
Output Current Waveform (including Dynamic Bias)
(mA)
(mA)
Normalized Time
Normalized Time
Dynamic Bias Current Waveform
Large-Signal Network Analysis Tools and Techniques Page 80
Agenda
Introduction Large-Signal Network Analysis The Large-Signal Network Analyzer Calibration The core of the LSNA Technology Examples A typical LSNA measurement session Next steps in LSNA Technology Wrap-up
Large-Signal Network Analysis Tools and Techniques Page 81
LSNA possible next steps driven by customer needs Extending modulation BW (3G) Increase power capability Extending frequency range (50 GHz and beyond …) Offer pulsed measurements to isolate the thermal effects Complete dynamic bias testing capabilities to characterize the effects
of modulation on bias Add impedance tuning measurements to determine the impact of
differing impedance conditions Use of LSNA technology in high speed digital applications
Large-Signal Network Analysis Tools and Techniques Page 82
Example: Extending Power Capability
Acquisition
Calibration
Stimulus
ReferencePlanes
ModulationSource
Pre-matchingProper calibration elementsOn - board DC biasTuners
?
3rd party
Adapt test - setProper absolute calibrationMeasurement science
Agilent NMDG
Large-Signal Network Analysis Tools and Techniques Page 83
Agenda
Introduction Large-Signal Network Analysis The Large-Signal Network Analyzer Calibration The core of the LSNA Technology Examples A typical LSNA measurement session Next steps in LSNA Technology Wrap-up
Large-Signal Network Analysis Tools and Techniques Page 84
Wrap-up Large-Signal Network Analysis Technology is breakthrough technology to
characterize nonlinear behavior from transistor to system The technlogy is targeted toward research and design experts. It requires a
strong background in RF or Microwave theory to be successful. Agilent NMDG is assigned to make the technology a success with early-
adopter key customers More information at : “http://wirelesscentral.tm.agilent.com/wirelesscentral/cgi-
bin/epsg.cgi” If you think the LSNA technology can help you, please contact