1. S-functions
“The S-parameters
for nonlinear components”
- Measure, Model, Verify,
Simulate -
An application in ICE
March 2011

2. Outline
● Why S-functions? What is the impact?
● S-functions, the “S-parameters” for all nonlinear applications?
● S-functions: Key Benefits
● Theory: from S-parameters to S-functions
● Applicability and Assumptions of S-functions
● Confidence in S-functions
● S-function Extraction and Verification Tool
● Deployment of S-functions in ADS and MWO / VSS
● Strengths and Key Capabilities
● References
● Conclusion
© 2011 2

3. Why S-parameters?
DESIGN
● Complete characterization of a component in linear mode of operation
● Derive insertion loss, return loss, gain, …
● S-parameters enable system-level interpretation of behavior of the
component
● Low – pass filtering, high reflective, ...
● S-parameters enable design in conjunction with other circuits
TEST in Manufacturing
● S-parameters can be extracted for the designed circuit
● The S-parameters can be measured for the manufactured circuit and can
be compared
S-parameters close the characterization, design and test loop
© 2011 3

4. S-parameter Design- and Test-Cycle for Linear Applications
At the Foundry
Design kit
Design library
Passive [S-parameter based]
S-parameters
Devices
Semiconductor Manufacturer
© 2011 4

5. S-parameter Design- and Test-Cycle for Linear Applications
At the Semiconductor Manufacturer
Design Chips S-parameters Design kit
Design library
[S-parameter based]
Iterations almost completely eliminated
Design Houses System Manufacturers
© 2011 5

6. Beyond S-parameters???
● S-parameters, the behavioural model for “linear” applications
● Components in linear mode of operation only
● Filters
● Transistors under small signal of excitation
● ...
● Their success is based on its uniform approach for linear RF and microwave
problems both to measure and to simulate
● What about components in nonlinear mode of operation?
● No uniform approach for nonlinear RF and microwave problems
● There is a lot of “trial and error” or “measure – tweak”
● S-parameters are used mainly during device modelling in conjunction with a lot of
model expertise to go from small-signal to large-signal
© 2011 6

7. “Trial-Error” Design- and Test-Cycle for “Nonlinear” Applications
At the Foundry
Design kit
Design library
Modelling
Devices (6 months)
Small-Signal
Large-Signal
Load-Pull
Mathematics...
Semiconductor Manufacturer
© 2011 7

8. “Trial-Error” Design- and Test-Cycle for “Nonlinear” Applications
At the Semiconductor Manufacturer ● Models do not meet the needs of application
● To time costly to develop own models
● Wafer fabs cannot worry about specific problems
Initial Chips DataSheet
Design Eval Board
Trial and Error
Design Houses System Manufacturers
© 2011 8

9. The Magic ...
S-Parameters
S-
S-functions
© 2011 9

10. The S-function Design- and Test-Cycle for Active Devices
At the Foundry
Design kit
Design library
[S-functions based (*)]
Devices S-Functions
Semiconductor Manufacturer
(*) S-functions for different applications
© 2011 10

11. The S-function Design- and Test-Cycle for Active Devices
At the Semiconductor Manufacturer
Improving S-functions with application-specific information
Design Chips S-functions Design kit
Design library
[S-functions based]
Reducing the number of iterations
Design Houses System Manufacturers
© 2011 11

12. Why S-functions? Adopting the S-parameter paradigm
DESIGN
● “Complete” characterization of a component in nonlinear mode of operation
for specific applications under a relevant set of conditions
● Derive “insertion loss”, “return loss”, “gain”, “mismatch”, conversion coefficients
● S-functions enable system-level interpretation of behaviour of the
component
● Power- dependent Low – pass filtering, power conversions, …
● Ideal for dividers, multipliers and mixers
● S-functions enable design in conjunction with other circuits
● When the signals are limited to the relevant set of conditions
TEST in Manufacturing
● S-functions can be extracted for the designed circuit
● The S-functions can be measured for the manufactured circuit and can be
compared
S-functions close the characterization, design and test loop
© 2011 12

13. S-Functions, the “S-parameters” for nonlinear applications?
● S-Functions, the behavioural model for nonlinear applications
● Deal with a subset of nonlinear RF and microwave phenomena in a uniform way
as a natural extension of S-parameters
● Will not solve “all” nonlinear problems
S-parameters Linear
Applications All
Other
Applications
S-functions NonLinear (*)
Applications
● Can be “measured”
How to define the
application boundary?
● Can be used for design in simulators
● Can be used for test to compare with realizations in simulator
(*): Nonlinear behaviour determined by a small number (e.g. 2) of tones
© 2011 13

14. S-Functions – Key Benefits
S-Functions are for nonlinear applications ...
... what S-parameters are for linear applications
● Simplify the use of HF components and circuits
● Complement limited data sheets with more complete system-level models
● Complement evaluation boards, enabling upfront more realistic simulations
● Improve and speed up the design and test process
● Adequate replacement when classic models fail
● Simulate with a behavioural model, optimized for your design problem
● Same Look and Feel as S-parameters: measure, model, verify and simulate
● Verify the realized circuit with S-functions against the simulation during test
● Shorter time to market for component manufacturers and buyers
© 2011 14

15. From S-parameters to S-functions
S-parameters measured at fixed DC bias point
S f 
VDC
f f
IDC
Keep signal small to
f stay in a linear mode
of operation
S-parameters measured at different DC bias points
Linear S V DC ; f 
Nonlinear I DC V DC 
Remark: for the sake of intuitive explanation, mathematics is not 100% correct
© 2011 15

16. From S-parameters to S-functions
f0 2f
0
3f
0
f0
A1  f 0  VDC
B2 k f 0 k : 1... 3 ...
f0
B1 k f 0 A2=0
50
k : 1... 3 ...
f0
2f 3f
0 0
Simple model and “easy” to measure
Nonlinear Bm n f 0=F mn V DC , f 0 ,∣a 1  f 0∣
Nonlinear I DC =H V DC , f 0 ,∣a 1  f 0 ∣
© 2011 16

17. From S-parameters to S-functions
Simple model and “easy” to measure
Bm n f 0=F mn V DC , f 0 ,∣a 1  f 0∣
I DC =H V DC , f 0 ,∣a 1  f 0 ∣
● AM-AM
● AM-PM
● Harmonic Distortion
But not useful in the real world
● S-functions should be able to predict cascades
Input contains harmonics !!
“Easy” to measure .... not in reality f0 A1  k f 0
2f
●
0 3f
0
● Harmonic distortion of source A2 l f 0
● Imperfect match at input and output
© 2011 17

18. From S-parameters to S-functions
A1  k f 0 f0 2f 3f
f0 0 0
B2 k f 0
2f
0
3f VDC
0
f0 k : 1... 3 ...
B1 k f 0 A2 k f 0 
ZL
f0
f0
2f 3f 2f 3f
0 0 0 0
Bm n f 0=F mn V DC , f 0 ,∣a 1  f 0∣
I DC =H V DC , f 0 ,∣a 1  f 0 ∣
“Simple” model extension
Bm n f 0=F mn V DC , f 0 ,∣a i  j f 0 ∣ , all phase comb of ai  j f 0
I DC =H V DC , f 0 ,∣a i  j f 0∣ , all phase comb of  ai  j f 0 
© 2011 18

19. From S-parameters to S-functions
Bm n f 0=F mn V DC , f 0 ,∣a i  j f 0 ∣ , all phase comb of ai  j f 0
I DC =H V DC , f 0 ,∣a i  j f 0∣ , all phase comb of  ai  j f 0 
Huge number of combinations with sweeps in amplitude and phase
© 2011 19

20. From S-parameters to S-functions
What now ???
f0 f0 2f
0
3f
0
2f 3f
0 0 VDC
A1  k f 0 B 2  k f 0
f0
B1 k f 0  f0 A2 k f 0  ZL
f0
2f 3f 2f 3f
0 0 0 0
© 2011 20

21. From S-parameters to S-functions
f0 f0 2f
0
3f
0
2f 3f
0 0 VDC
A1  k f 0 B 2  k f 0
f0
B1 k f 0  f0 A2 k f 0  ZL
f0
2f 3f 2f 3f
0 0 0 0
In many cases : A1  k f 0 , A2 k f 0  with k 1 SMALL
Linearize equations in A1  k f 0 , A2 k f 0  with k 1
© 2011 21

22. From S-parameters to S-functions
The intuitive approach
f0 f0 2f
0
3f
0
VDC
A1  f 0  B2  k f 0
f0
B1 k f 0  f0 A2  f 0  ZL
f0
2f 3f
0 0
© 2011 22

23. From S-parameters to S-functions
f0 f0 2f
0
3f
0
2f
0 VDC
A1  k f 0 B2  k f 0
f0
B1 k f 0  f0 A2  f 0  ZL
f0
2f 3f
0 0
© 2011 23

24. From S-parameters to S-functions
x2
f0 f0 2f 3f
2f 0 0
0
x2 VDC
A1  k f 0 B2  k f 0
f0
B1 k f 0  f0 A2  f 0  ZL
f0
x2 2f 3f
0 0
LINEAR
But with frequency conversion, like a mixer
© 2011 24

25. From S-parameters to S-functions
f0 f0 2f
0
3f
0
2f 3f
0 0 VDC
A1  k f 0 B2  k f 0
f0
B1 k f 0  f0 A2  f 0  ZL
f0
2f 3f
0 0
LINEAR Superposition
© 2011 25

26. From S-parameters to S-functions
f0 f0 2f
0
3f
0
2f 3f
0 0 VDC
A1  k f 0 B2  k f 0
f0
B1 k f 0  f0 A2 k f 0  ZL
f0
2f 3f 2f
0 0 0
© 2011 26

27. From S-parameters to S-functions
f0 f0 2f
0
3f
0
2f 3f
0 0 VDC
A1  k f 0 B2  k f 0
f0
B1 k f 0  f0 A2 k f 0  ZL
f0
2f 3f 2f 3f
0 0 0 0
© 2011 27

28. From S-parameters to S-functions
The Mathematical Approach
Bm n f 0=F mn V DC , f 0 ,∣a i  j f 0 ∣ , all phase comb of ai  j f 0
I DC =H V DC , f 0 ,∣a i  j f 0∣ , all phase comb of  ai  j f 0 
Linearization
The S-functions
*
I DC =Sf 0001 V DC , A11 , A21 Sf 00ij V DC , A11 , A21  Aij Sfc 00ij V DC , A11 , A21  Aij
*
Bmn =Sf mn01 V DC , A11 , A21 Sf mnij V DC , A11 , A21 Aij Sfc mnij V DC , A11 , A 21 Aij
“LSOP”
Sf mnij “Tickle tone”
m: output port with j 1
n: frequency at output port m
i: input port with B mn≡B m n f 0 
j: frequency at input port i
with Aij ≡ Ai  j f 0 
LSOP: large-signal operating point Sweep in strongly reduced LSOP
© 2011 28

29. Sfc ???
f0 f0 2f
0
3f
0
2f
0 VDC
A1  k f 0 B2  k f 0
f0
B1 k f 0  f0 A2  f 0  ZL
f0
2f 3f
0 0
© 2011 29

30. Sfc ???
f0 f0 2f
0
3f
0
2f + df
0 VDC
A1  k f 0 B2  k f 0
f0 df
B1 k f 0  f0 A2  f 0  ZL
f0
2f 3f
0 0
df
© 2011 30

31. Sfc ???
*
A
kl
f0 f0 2f
0
3f
0
2f + df
0 VDC
A1  k f 0 B2  k f 0
f0 df
B1 k f 0  f0 A2  f 0  ZL
f0
2f 3f
0 0
df
© 2011 31

32. How to extract S-functions?
Select a LSOP and keep it constant
*
Bmn =Sf mn01 V DC , A11 , A21 Sf mnij V DC , A11 , A21  Aij Sfcmnij V DC , A11 , A 21  Aij
constant constant constant
Change the tickle tones
Measure each time Aij , B mn
Solve for the S-functions : Sf mnij LSOP , Sfc mnij  LSOP
Select a new LSOP and repeat
© 2011 32

33. Extract S-functions for a real device
DC Bias f0
f0 or
Large-Signal Tickling
Source k f0 ZL
Source
DC Bias
● Repeat the following for all LSOPs of interest
● Select tickle tones Large-Signal
● Large enough to be detectable Source Tickling
Source
● Small enough not to violate linearity assumption
● Measure incident and reflected waves for different tickle tones
● Model by solving for all Sf and Sfc
● Resulting into S-functions
© 2011 33

34. S-functions for Real Devices with ZVxPlus
Bias
ZVxPlus
Tickling
Source
Large-Signal
Source
© 2011 34

35. Extract S-functions for a simulated device
Bias Settings Large-Signal Source Settings
Tickling Source Settings
Tickling
Source
Bias Bias
Large-Signal
Source
© 2011 35

36. Assumptions of S-functions
VDC
v3
i3
a1 a2
DUT
b1 b2
`
a 1 k f 0  , a 2 l f 0  with l , k ≠0,1
Is causing only a LINEAR perturbation on the NONINEAR behaviour
Large-Signal Operating Point (LSOP) Tickle or probing tones
a 1  f 0 , a 2  f 0 and v dc a 1 k f 0  , a 2 l f 0 with l , k ≠0,1
© 2011 36

37. The crucial question for S-functions
S-parameters Linear
Applications All
Other
Applications
Some
S-functions NonLinear
Applications
Mathematically well-defined To what applications does it apply?
a 1 k f 0  , a 2 l f 0 with l , k 1 SMALL
20 dBc down from main tone
BUT
© 2011 37

38. Applicability of S-functions
a1 a2 a3
DUT X DUT Y
b1 b2 b3
Components Prediction
● Transistors ● Harmonic distortion
● Amplifiers ● AM – AM and AM – PM
● Dividers ● Source-pull
● Multipliers ● Load-pull
● Modulation behaviour (*)
● Intermodulation
(*)
: The component is assumed to be pseudo-static
© 2011 38

39. S-functions in ICE(*)
● Sweepable Large-Signal Operating Point (LSOP)
● Auto or user-defined tickle signal level
● From simple push-the-button solution to access to expert-level details
● Visualization of component behaviour during data collection
● Easy model verification (no EDA tool required)
● Sanity checks included
● Easy export to and integration in Agilent™ ADS and AWR™ MWO
● Support for mismatched environments
● Harmonics generated by RF sources don't cause any problem
● Simple output prediction does not require EDA tool
● Export to and integration in other EDA tools on request
● Possible to extend the LSOP variables, e.g. temperature
(*)
Integrated Component Characterisation Environment
© 2011 39

40. Confidence in S-functions
● Constantness of LSOP
● All Sf, and Sfc are assumed to be extracted at fixed LSOP
● e.g. variation in DC drain voltage due to changing current violates this assumption
● Interpolation capability of all Sf, and Sfc
● LSOP interleaving verification measurements
● Linearity assumption of tickle tones
● Model verification for different amplitude and phases of tickle tones
Confidence
Extract
Measure through Simulate
S-functions
Verification
© 2011 40

41. Confidence in S-functions through Verification
ADS
MWO
ADS: Agilent Technologies Advanced Design Systems design software
MWO: AWR Corporation's Microwave Office design software
© 2011 41

42. S-functions for Real and Simulated Components / Circuits
Measurements Simulations
Data Collection on Real Devices On Virtual Devices
using ICE (*) in Simulation Tool (ADS - MWO)
Extraction
S-functions
S-functions Verifications
Simulators
S-functions Deployment
(ADS - MWO)
© 2011 42

43. S-functions Verification – Constantness of LSOP
Select LSOP variable
Variation on
Filter for a LSOP variable drain bias voltage
and value
Variation on fixed input power
© 2011 43

44. S-functions Verification – Interpolation Capability
verify interpolation of b2 using independent set of measurements
© 2011 44

45. S-functions Verification – Linearity Assumption of Tickle Tones
Large-Signal DC Bias f0
f0 or
Large-Signal Tickling
Source k f0 ZL
Source
Small-Signal
for harmonics DC Bias
DC Bias a 2 k f 0
Switching Amplifier design
 L 2 f 0   L  k f 0
 L 3 f 0
a 2 2 f 0 
Still small signal?
a 2 3 f 0
© 2011 45

46. ICEBreaker – Option S-function Verification Tool
ICEBreaker Predicted Compare
Dataset ICEBreaker Datasets
Dataset
● Measured Data ● Using S-function ● Derived Quantities
● Realistic Sweep Plan ● Incident / Reflected Waves
● Under multi-harmonic Load-Pull ● Voltage and Current
● Absolute Error
● Relative Error
© 2011 46

47. Generation of “S-function Predicted Dataset” in ICEBreaker
Generate
S-function based
Dataset
Compare
Dataset
and
S-function based
Dataset
© 2011 47

48. Absolute Comparisons with S-function Predictions
Quantity for
which to compare
measurement and Idc_out
prediction
● Derived quantities
➢ Idc_out
➢ Gain
➢ Pdel_in
➢ Pdel_out
➢ PAE
➢ ..
➢ Frequency selection
● Basic quantities
➢ Incident waves
➢ Reflected waves
➢ Voltages / Currents
➢ Frequency selection
Measurements
S-function
Prediction
Absolute Error
© 2011 48

49. Relative Comparisons with S-function Predictions
b_out(3f0)
● Versus
➢ Harmonic index
➢ Harmonic refl
Relative Error (dB)
© 2011 49

50. Case Study(*): EPA120B-100P
 EPA120B-100P
• high efficiency heterojunction power FET
• power output: + 29.0dBm typ.
• power gain: 11.5dB typ. @ 12 GHz
Real Device Virtual Device
(*)
: all results in this slide set are based on S-function extraction and deployment for this device
© 2011 © 2009 - NMDG NV 50

51. Data Collection with ZVxPlus
LSOP “tickle”
sweep settings
detailed detailed
feedback feedback
of LSOP on tickle
for actual for actual
measurement measurement
© 2011 51

52. Expert Details If Desired @ Data Collection
Summary
Monitor
RF and DC
source
settings
Observe
what happens
at the DUT
© 2011 52

53. S-functions Extraction
S11
S12
S22
S21
meaningful
complex
~3 dB compression conjugate
© 2011 53

54. S-functions Verifications – Residual Error
zoom in
on zoom in
tickling on result
Number of measurements
required to extract
S-functions
amplitude of complex error for measured and predicted b2 using extraction data
© 2011 54

55. S-functions Verification – Interpolation Capability
verify interpolation of b2 using independent set of measurements
© 2011 55

56. S-functions Verifications – Constantness LSOP
Select LSOP variable
Variation on
Filter for a LSOP variable drain bias voltage
and value
Variation on fixed input power
© 2011 56

57. S-functions in ADS
Acknowledgement:
With the support from Agilent Technologies providing ADS licensing
© 2011 57

58. S-functions Useage in Agilent ADS
EPAClassAMediumPower.ael
EPAClassAMediumPower.dsn
Set of equations using FDD
Values of all Sf, Sfc
© 2011 58

59. S-functions Verification in ADS - Schematic
● Example: Harmonic Balance simulation with measured a1 and a2 spectra
● Excitation: Sweeping through a subset of LSOP points + tickle tones
Measured incident waves
S-function to be verified
Measurements for model verification
Access to measured data
using DAC
Sweeping through subset
of LSOP and tickle tones
© 2011 59

60. S-functions Verification in ADS - Frequency Domain
Frequency = 2 GHz, VDC1= -1.3 V, VDC2= +2.0 V
Measurements at different
input powers than those
which were used for
S-functions model extraction!
circles – measurements
solid lines - simulations
© 2011 60

61. S-functions Verification in ADS - Time Domain
circles – measurements
Frequency = 2 GHz, VDC1= -1.3 V, VDC2= +2.0 V, Pa1 = +10.0 dBm solid lines - simulations
Saturation
Pinch-off
© 2011 61

62. S-functions in ADS – Modulation Prediction - Schematic
Frequency = 2 GHz, VDC1= -1.37 V, VDC2= +4.0 V, Pa1 = +0.0 dBm – Class C
© 2011 62

63. S-functions in ADS – Modulation Prediction - Display
Frequency = 2 GHz, VDC1= -1.37 V, VDC2= +4.0 V, Pa1 = +0.0 dBm – Class C
© 2011 63

64. S-functions in ADS – Source-Pull - Schematic
Frequency = 2 GHz, VDC1= -1.37 V, VDC2= +4.0 V, Pav = +1.0 dBm – Class C
Reflection : -0.27
© 2011 64

65. S-functions in ADS – Source-Pull - Schematic
Frequency = 2 GHz, VDC1= -1.37 V, VDC2= +4.0 V, Pav = +1.0 dBm – Class C
Complex Conjugate
Measured Input Impedance
© 2011 65

66. S-functions in MWO
Acknowledgement:
With the support from AWR providing MWO / VSS licensing
© 2011 66

67. S-functions Usage in AWR MWO
MDF file SUBCKT
ID=S1 BIASTEE
NET="SFUNC_Model" ID=X2
1 RF 2
& RF
BIASTEE 2 DC
DC
ID=X1 PORT
3 P=2
Z=50 Ohm
Model data
2 RF 1 1
RF &
DC
DC
PORT_PS1 3 DCVS ..
P=1
Z=50 Ohm
ID=V2 ..
V=6 V
PStart=PinMin dBm 1.16226472890446E-16,-1.35308431126191E-16
PStop=PinMax dBm
PStep=PinStep dB
-3.15025783237388E-15,4.72191730160887E-15
DCVS
ID=V1 9.71445146547012E-17,-2.37310171513627E-15
V=-1.8 V 1.51267887105178E-15,1.07899800205757E-15
-2.98198965520413E-15,1.59594559789866E-15
-5.759281940243E-16,-1.97758476261356E-16
-1.83880688453542E-15,1.92901250528621E-15
-5.06539254985228E-16,2.94209101525666E-15
-2.50494069931051E-15,-6.73072708679001E-16
-8.60422844084496E-16,2.65412691824451E-16
-2.019218126037E-15,2.7373936450914E-15
-2.28289609438548E-15,1.70870262383715E-15
1.08246744900953E-15,-6.78276879106932E-16
-1.02955838299224E-15,-1.31578775652841E-15
5.45570533194706E-16,3.99333344169861E-15
-3.62904151174348E-15,-1.74860126378462E-15
-2.00100352953925E-15,-5.68989300120393E-16
2.14975606760426E-15,-5.53376788836601E-16
-1.16226472890446E-15,-2.44942954807925E-15
2.08166817117217E-16,2.4980018054066E-15
1.04372118124342E-05,-1.36061371223614E-05
2.85882428840978E-15,3.11556336285435E-15
-2.15105711021124E-16,1.37390099297363E-15
9.71445146547012E-16,9.95731275210687E-16
-1.69309011255336E-15,2.33146835171283E-15
4.27435864480685E-15,3.3584246494911E-15
-1.08246744900953E-15,-8.60422844084496E-16
…
2D and 3D package data
© 2011 67

68. S-functions Verification in MWO - Frequency Domain
HBT UNER2
ID=X1
Mag1=0
Ang1=0 Deg
Mag2=0
Ang2=0 Deg
Mag3=0
Ang3=0 Deg
Fo=2 GHz
Zo=50 Ohm
PORT _PS1
P=1 1 2
Z=50 Ohm
PStart=-20 dBm BIAST EE 2
PStop=8 dBm ID=X2 PORT
PStep=1 dB 3:Bias P=2
SUBCK T
2 RF 1 1 Z=50 Ohm
RF & ID=S1
DC NET ="EPA_120_B "
DC
3 DCVS
ID=V1
V=DC2val V
DCVS
ID=V2
V=DC 1val V
Po with swept Pin Gain and Phase with swept Pin
40 20
19.5
20 19
F0 18.5
DB(|LSSnm(PORT_2,PORT_1,1,1)|)[1,X]
0 18 Swept Power.AP_HB
Ang(LSSnm(PORT_2,PORT_1,2,1))[1,X] (Deg)
17.5 Swept Power.AP_HB
-20 17
150
2F0
-40 100
DB(|Pcomp(PORT_2,1)|)[1,X] (dBm)
Swept Power.AP_HB
50
3F0 DB(|Pcomp(PORT_2,2)|)[1,X] (dBm)
-60 Swept Power.AP_HB
DB(|Pcomp(PORT_2,3)|)[1,X] (dBm)
Swept Power.AP_HB
0
-80 -50
-20 -15 -10 -5 0 5 10 -20 -15 -10 -5 0 5 10
Power (dBm) Power (dBm)
© 2011 68

69. S-functions Verification in MWO - Time Domain
Vtime(V_METER.VM1,1)[*,T] (V) Itime(I_METER.AMP1,1)[*,T] (mA)
HBTUNER2 Waveform Tests.AP_HB Waveform Tests.AP_HB
ID=X1
Mag1=0
Ang1=0 Deg
Mag2=0
Ang2=0 Deg
Mag3=0
IV
Ang3=0 Deg 250
Fo=2 GHz
SUBCKT Zo=50 Ohm
PORT_PS1 ID=S1 200
P=1 NET="EPA_120_B" 1 2
Z=50 Ohm
PStart=-20 dBm BIASTEE 2 150
PStop=8 dBm ID=X2 PORT
PStep=1 dB I_METER 3:Bias P=2
2 RF 1 1 ID=AMP1 Z=50 Ohm 100
RF &
DC
DC 50
3 V _METER DCVS
ID =VM1 ID=V1
V=DC2val V
0
15
DCVS
ID=V2
V=DC1val V
10
5
DB(|Pcomp(PORT_2,1)|)[1,X] (dBm) DB(|Pcomp(PORT_2,2)| )[1,X] (dBm) DB(|Pcomp(PORT_2,3)|)[1,X] (dBm)
Waveform Tests.AP_HB Waveform Tests.AP_HB Waveform Tests.AP_HB0
0 0.2 0.4 0.6 0.8 1
Harmonics
40 Time (ns)
20
0
-20
-40
-60
-80
-20 -10 0 8
Power (dBm)
© 2011 69

70. S-functions in MWO – Modulation Prediction - Schematic
DB(PWR_SPEC(TP.AMP Out,1000,0,10,0,-1,0,-1,1,0,4,0,1,0)) (dBm) DB(PWR_SPEC(TP.AMP In,1000,0,10,0,-1,0,-1,1,0,4,0,1,0)) (dBm)
16QAM System 16QAM System
HBTUNER2
ID=DCBlock2
Mag1=0
Ang1=0 Deg
Mag2=0
Ang2=0 Deg
Mag3=0 ACPR
SUBCKT
Ang3=0 Deg
Fo=2000 GHz 50
ID=S1 Zo=50 Ohm
ISOL8R NET="EPA_120_B"
ID=U1 1 2
R=50 Ohm
LOSS=0 dB BIASTEE 2
ISOL=30 dB ID=X1 PORT
3:Bias P=2
2
RF
RF
&
1 1 Z=50 Ohm 0
DC
DC
PORT_PS1 3 DCVS
P=1 ID=V3
Z=50 Ohm V=DC2val V
PStart=-20 dBm
PStop=8 dBm
PStep=0.5 dB
DCVS
-50
ID=V1
V=DC1val V
-100
-150
1.92 1.94 1.96 1.98 2 2.02 2.04 2.06 2.08
Frequency (GHz)
VS A
ID=M1
VA RNA ME=""
VA LUE S=0
NA VG=
PBA SE = -76 V e c to r
S w e p t v a r ia b le S ig n a l
SRC MEAS
A n a ly z e r
QAM_S RC G e n e r a l R e c e iv e r
ID=A1
MO D=16-QA M (Gray)
OUT LV L=-0.2
OLVLT Y P=Avg. Power (dB m) NL_ S
AW GN
RAT E=_DRA T E ID=S 1 BER
ID=A3
CTRFRQ=2 GHz TP NET ="AMAM A MPM.AP_HB " PW R=-170 ID=5
SIMT YP=Harm onic Balanc e TP
PLST Y P=Root Rais ed Cos ine ID=AMP In PW RT YP=Avg. Po wer, Sym bol (dBW ) VARNAME="PBA SE"
ID=AMP Out
ALPHA =0.35 NO SE=RF Budget only
I VALUES=s tepped(-76,-40,2)
LOSS=0 dB
PLSLN= RFIF RQ= QAM_RX OUT FL=""
ID=A 2
1 R D
2 BER
IQ 3
C irc u it 5 4
B E R D e te c to r
B a s e d A m p lifie r C h a n n e l N o is e
1 6 Q A M S o u rc e TP
ID=RX Cons tellation
1 6 Q A M (G r a y ) S y s te m
© 2011 70

71. S-functions in MWO – Load-Pull
HBTUNER2
ID=DCBlock2
Mag1=0.8
Load Tuner (and bias)
Ang1=40 Deg
LP_Data_Low_Power Mag2=0
Ang2=0 Deg
1.0 Swp Max Mag3=0
0.8
-0.89 Ang3=0 Deg
Fo=2 GHz
6
0.
Zo=50 Ohm
0
.
2
4
. 1 2
PORT1
0
0
.
3
P=1 2
p8 0
p1: Pcomp_PORT_2_1_M_DB = -2.87 Z=50 Ohm PORT
p7 4.
Pwr=10 dBm 3:Bias P=2
p9 p2: Pcomp_PORT_2_1_M_DB = -2.65 SUBCKT
5.
0
2 RF 1 Z=50 Ohm
2
p6 1 ID=S1
0.
RF &
p10 p3: Pcomp_PORT_2_1_M_DB = -2.43 DC NET="SFUNC_Model"
p5 DC
10.
0
BIASTEE
p4: Pcomp_PORT_2_1_M_DB = -2.21 3 DCVS
ID=X1
p4 ID=V2
10.0
V=7 V
4.0
p5: Pcomp_PORT_2_1_M_DB = -1.99
0.2
0.4
0.6
0.8
1.0
2.0
3.0
5.0
0
p3
p6: Pcomp_PORT_2_1_M_DB = -1.77 DCVS
p2
ID=V1
.0
-10 p7: Pcomp_PORT_2_1_M_DB = -1.55 V=-0.6 V
p1
-0
.
2
0
.
p8: Pcomp_PORT_2_1_M_DB = -1.33
-5
0
.
-4
p9: Pcomp_PORT_2_1_M_DB = -1.11
p10: Pcomp_PORT_2_1_M_DB = -0.89
0
.
3
4 -
.
0
-
0
.
2
6
-
.
-0
8
Swp Min
-1.0
-0.
-2.87
LP_Data_High_Power
S M
wp ax
1.0
0 .8
25.93
6
0.
.0
2
.4
0 p1: Pcomp_PORT _2_1_M_DB = 21.93
.0
3
p9
p8 p7 p6 p5 p2: Pcomp_PORT _2_1_M_DB = 22.33
p4 4 .0
2
p10 p3 5.
0
p3: Pcomp_PORT _2_1_M_DB = 22.73
0.
p2
0
p4: Pcomp_PORT _2_1_M_DB = 23.13
1 0.
p11
p5: Pcomp_PORT _2_1_M_DB = 23.53
10.0
0.4
0.8
3.0
0.2
0.6
1.0
2.0
4.0
5.0
p1
p6: Pcomp_PORT _2_1_M_DB = 23.93
0
0 .
p7: Pcomp_PORT _2_1_M_DB = 24.33
- 10
p8: Pcomp_PORT _2_1_M_DB = 24.73
.2
-0 .0
.0
-5
p9: Pcomp_PORT _2_1_M_DB = 25.13
-4
0 p10: Pcomp_PORT _2_1_M_DB = 25.53
3.
4 -
0.
- p11: Pcomp_PORT _2_1_M_DB = 25.93
0
2.
.6
-
-0
8
S M
wp in
-1.0
- 0.
21.93
© 2011 71