Preface ..................................................... xi
Acknowledgments ............................................ xiv
1 Wireless signals ............................................. 1
1.1 Modern wireless communications .......................... 1
1.2 OFDM primer ............................................. 3
1.3 Impact of clipping on OFDM .............................. 9
1.4 Spectral regrowth and clipping ......................... 12
1.5 Metrics ................................................ 13
1.6 Multisine .............................................. 14
References .................................................. 15
2 Large-signal vector measurement techniques with NVNAs ....... 17
2.1 Measurement of RF signals .............................. 17
2.2 Principle of operation of vector large-signal
measurements ........................................... 19
2.3 Sampler-based principle of operation ................... 23
2.4 Relative and absolute power and harmonic phase
calibrations ........................................... 27
2.4.1 Calibration for connectorized devices ........... 27
2.4.2 On-wafer calibration ............................ 33
2.5 Tuner deembedding with the LSNA ........................ 35
2.5.1 Definitions ..................................... 36
2.5.2 Extraction of βC, γC, and δC in TC .............. 38
2.5.3 Extraction of (1/KC) TP ......................... 38
2.5.4 Extraction of LRRM(Zx) .......................... 39
2.6 Modulated measurements and IF calibration .............. 39
2.6.1 Absolute time reference calibration for RF
modulated measurements .......................... 40
2.7 Broadband measurements with the LSNA ................... 42
2.7.1 Principle of phase calibration .................. 44
2.7.2 Experimental results and discussions ............ 48
2.8 Pulsed-RF small- and large-signal measurements ......... 51
2.8.1 Analysis of pulsed-RF signals ................... 52
2.8.2 Pulsed I-V pulsed-RF measurement system with
the LSNA ........................................ 53
2.8.3 Measurement bandwidth ........................... 55
2.8.4 Envelope analysis of pulsed-RF signals .......... 56
2.9 Multiple recording of pulsed-RF signals ................ 58
2.9.1 Multiple recording for CW signals ............... 59
2.9.2 Multiple recording for jointly pulsed and
modulated signals ............................... 62
References .................................................. 63
3 Device modeling and verification with NVNA measurements ..... 66
3.1 Model verification ..................................... 66
3.2 Model symmetry ......................................... 72
3.3 Device parasitics ...................................... 75
3.4 Model extraction from power-sweep measurements ......... 81
3.5 Model extraction from dynamic loadline measurements .... 83
References .................................................. 87
4 Characterization and modeling of memory effects in RF
power transistors ........................................... 89
4.1 Importance of memory effects in RF devices ............. 89
4.2 Distributed and transient models for self-heating in
power transistors ...................................... 90
4.2.1 Steady-state thermal modeling ................... 90
4.2.2 Implementation of the distributed thermal
model ........................................... 92
4.2.3 Transient thermal response ...................... 94
4.2.4 Modeling of the transient thermal response ...... 96
4.3 Identification of self-heating using pulsed I-V
pulsed-RF measurements ................................. 98
4.3.1 CW dynamic loadline measurement system .......... 99
4.3.2 Pulsed I-V pulsed-RF loadline measurement
system .......................................... 99
4.3.3 Origin of the I-V knee walk-out in the CW-RF
loadlines ...................................... 100
4.4 Trapping in GaN HEMTs ................................. 103
4.5 Characterization with a combined LSNA/DLOS system ..... 105
4.6 Quasi-static device parasitics ........................ 108
4.7 Rate equation for physical modeling of trapping
effects ............................................... 111
4.8 Two-trap-level model .................................. 113
4.9 Cyclostationary effect ................................ 115
4.9.1 Theory ......................................... 115
4.9.2 Experimental investigations .................... 116
References ................................................. 120
5 Interactive loadline-based design of RF power amplifiers ... 124
5.1 Review of power amplifiers of various classes (A-F) ... 124
5.2 Output termination with load-pull measurements ........ 134
5.2.1 Active load-pull measurements .................. 135
5.2.2 Real-time active load-pull measurements ........ 136
5.3 Class-F design with RTALP ............................. 140
5.4 Complete design cycle for a pHEMT amplifier ........... 147
5.5 RTALP of PAs for pulsed I-V pulsed-RF class-B
operation ............................................. 150
5.6 PI dB contour plot .................................... 154
5.7 Class-E PA operation .................................. 155
References ................................................. 158
6 Behavioral modeling ........................................ 160
6.1 Behavioral model for SISO and MIMO systems ............ 160
6.2 Volterra modeling ..................................... 161
6.2.1 Volterra algorithm ............................. 162
6.2.2 Model derivation ............................... 165
6.2.3 Analytic example ............................... 168
6.2.4 Model extraction ............................... 171
6.2.5 Experimental model extraction and validation ... 172
6.2.6 Phase reference ................................ 174
6.2.7 Poly-harmonic distortion model (PHD) ........... 175
6.3 Single-band multi-harmonic envelope PA model .......... 179
6.3.1 Input signal ................................... 180
6.3.2 Orthogonal Chaillot expansion .................. 180
6.3.3 Memoryless nonlinear system modeling ........... 183
6.3.4 Quasi-memoryless nonlinear system modeling ..... 185
6.3.5 Power-series expansion ......................... 186
6.3.6 Multi-path model partitioning .................. 187
6.3.7 Time-selective single-band multi-harmonic
envelope PA model .............................. 187
6.4 Two-band fundamental envelope PA model ................ 190
6.4.1 Nonlinear power-amplifier characterization
with NVN A ..................................... 192
6.4.2 Extension to higher-order nonlinearities ....... 194
6.4.3 Modulated two-band model ....................... 195
6.5 Appendix: Volterra series expansion for a four-tone
excitation ............................................ 198
References ................................................. 200
7 Kurokawa theory of oscillator design and phase-noise
theory ..................................................... 201
7.1 Oscillator operating point ............................ 201
7.2 Kurokawa theory of oscillators ........................ 203
7.3 Vector measurement of device line with real-time
active load-pull ...................................... 207
7.3.1 Test oscillator circuit ........................ 207
7.3.2 Real-time multi-harmonic active load-pull
system ......................................... 208
7.3.3 Experimental results ........................... 209
7.3.4 Self-oscillation test .......................... 213
7.4 Impact of white noise on an oscillator ................ 215
7.5 Impact of 1/ƒ noise on an oscillator .................. 222
7.5.1 Derivation of Sα,1/ƒ(Δω) ....................... 223
7.5.2 Derivation of Sø,1/ƒ (Δω) ...................... 224
7.5.3 Range of validity of the Kurokawa equations .... 227
7.6 Injection locking and additive phase-noise
measurements .......................................... 229
7.6.1 Theory ......................................... 229
7.6.2 Experimental measurements ...................... 233
References ................................................. 235
8 Design, modeling, and linearization of mixers,
modulators, and demodulators ............................... 237
8.1 Vector characterization of an I-Q modulator ........... 237
8.1.1 Balancing of an I-Q modulator .................. 237
8.1.2 К modeling ..................................... 238
8.1.3 I-Q modulator characterization with LSNA ....... 240
8.1.4 К modeling of an I-Q modulator and an I-Q
demodulator chain .............................. 243
8.2 Polyphase multi-path technique ........................ 248
8.2.1 Nonlinear behavior ............................. 249
8.2.2 Polyphase multi-path technique ................. 249
8.3 Poly-harmonic modeling of a single-sideband
modulator ............................................. 253
8.3.1 Theory ......................................... 253
8.3.2 Poly-harmonic predistortion linearization
test results ................................... 257
References ................................................. 261
9 Linearization of RF power amplifiers with memory ........... 262
9.1 Predistortion linearization and the impact of memory
effects ............................................... 262
9.2 Predistortion for quasi-memoryless amplifiers ......... 266
9.3 Linearization for PAs modeled with memory
polynomials ........................................... 269
9.4 Two-band frequency-selective predistorter ............. 274
References ................................................. 279
Index ......................................................... 280
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