RF.Measurements.for.Cellular.Phones.and.Wireless.Data.Systems.Jul.2008: RF.Measurements.for.Cellular.Phones.and.Wireless.Data.Systems.Jul.2008.part2.rar

Copyright # 2008 by John Wiley & Sons, Inc. All rights reserved
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Library of Congress Cataloging-in-Publication Data:
Scott, Allan W.
RF measurements for cellular phones and wireless data systems/Allan W. Scott, Rex Frobenius.
p. cm.
ISBN 978-0-470-12948-7 (cloth)
1. Radio frequency integrated circuits—Testing. 2. Wireless communication systems—Equipment
and supplies—Design and construction. 3. Cellular telephones—Equipment and supplies—Design
and construction. I. Frobenius, Rex. II. Title.
TK7874.S36 2008
621.384506—dc22
2008004929
Printed in the United States of America
10 9 8 7 6 5 4 3 2 1

CONTENTS
1 INTRODUCTION 1
1.1 The Market for Cellular Phones and Wireless Data Transmission
Equipment / 1
1.2 Organization of the Book / 3
1.3 Part I: RF Principles / 4
1.4 Summary of Chapter 2: Characteristics of RF Signals / 4
1.5 Summary of Chapter 3: Mismatches / 4
1.6 Summary of Chapter 4: Digital Modulation / 4
1.7 Part II: RF Measurement Equipment / 9
1.8 Summary of Chapter 5: RF Signal Generators / 9
1.9 Summary of Chapter 6: Power Meters / 10
1.10 Summary of Chapter 7: Frequency Counters / 10
1.11 Summary of Chapter 8: VNAs / 14
1.12 Summary of Chapter 9: Spectrum Analyzers / 14
1.13 Summary of Chapter 10: VSAs / 17
1.14 Summary of Chapter 11: Noise Figure Meters / 17
1.15 Summary of Chapter 12: Coaxial Cables and Connectors / 19
1.16 Summary of Chapter 13: Measurement Uncertainties / 19
1.17 Summary of Chapter 14: Measurement of Components Without Coaxial
Connectors / 21
1.18 Part III: Measurement of Individual RF Components / 21
v
1.19 Summary of Chapter 15: RF Communications
System Block Diagram / 22
1.20 Summary of Chapter 16: Signal Control Components / 22
1.21 Summary of Chapter 17: PLOs / 22
1.22 Summary of Chapter 18: Upconverters / 24
1.23 Summary of Chapter 19: Power Amplifiers / 24
1.24 Summary of Chapter 20: Antennas / 29
1.25 Summary of Chapter 21: RF Receiver Requirements / 31
1.26 Summary of Chapter 22: RF Filters / 33
1.27 Summary of Chapter 23: LNAs / 35
1.28 Summary of Chapter 24: Mixers / 36
1.29 Summary of Chapter 25: Noise Figure Measurement / 38
1.30 Summary of Chapter 26: Intermodulation Product Measurement / 38
1.31 Summary of Chapter 27: Overall Receiver / 39
1.32 Summary of Chapter 28: RFICs and SOC / 39
1.33 Part IV: Testing of Devices and Systems with Digitally
Modulated RF Signals / 41
1.34 Summary of Chapter 29: Digital Communications Signals / 42
1.35 Summary of Chapter 30: FDMA, TDMA, and CDMA Multiple Access
Techniques / 44
1.36 Summary of Chapter 31: OFDM and OFDMA / 46
1.37 Summary of Chapter 32: ACP / 48
1.38 Summary of Chapter 33: Constellation, Vector, and Eye Diagrams, and
EVM / 48
1.39 Summary of Chapter 34: CCDF / 51
1.40 Summary of Chapter 35: BER / 53
1.41 Summary of Chapter 36: Measurement of GSM
Evolution Components / 54
1.42 Annotated Bibliography / 55
PART I RF AND WIRELESS PRINCIPLES 57
2 CHARACTERISTICS OF RF SIGNALS 59
2.1 Electric and Magnetic Fields / 60
2.2 Electromagnetic Waves / 62
2.3 Properties of RF Waves / 63
Frequency / 64
Wavelength / 64
Impedance / 67
vi CONTENTS
Power Density / 67
Phase / 68
2.4 RF Power Expressed in dB and dBm / 69
dB Terminology / 70
dBm Terminology / 72
2.5 Using dB and dBm to Determine an RF Link Budget / 73
2.6 Alternate Names for dB and dBm / 78
2.7 Annotated Bibliography / 78
3 MISMATCHES 79
3.1 The Mismatch Problem / 79
3.2 Ways of Specifying Mismatches / 80
3.3 Conversion Between Different Ways of Expressing Mismatch / 82
3.4 S-Parameters / 85
3.5 Matching with the Smith Chart / 87
3.6 Derivation of the Smith Chart / 89
3.7 Plotting Mismatches on the Smith Chart / 94
3.8 Matching Calculations with the Smith Chart / 99
3.9 Using Parallel Matching Elements / 103
3.10 Lumped Elements in Combination / 105
3.11 Smith Chart Software / 106
3.12 Annotated Bibliography / 111
4 DIGITAL MODULATION 113
4.1 Modulation Principles / 113
4.2 Multilevel Modulation / 115
4.3 Special Phase Modulation Techniques / 118
DPSK / 118
p/4QPSK / 119
3/8p 8PSK Modulation for EDGE / 119
4.4 Digital Frequency Modulation / 120
4.5 Upconversion Requirements / 122
4.6 Annotated Bibliography / 122
PART II RF MEASUREMENT EQUIPMENT 123
5 RF SIGNAL GENERATORS 125
5.1 What an RF Signal Generator Does / 125
CONTENTS vii
5.2 Supported Wireless Communication Formats / 127
5.3 RF Signal Generator Displays / 127
5.4 RF Signal Generator Controls / 127
5.5 Modulation Architectures / 129
5.6 Phase Noise of the RF Signal Generator / 130
5.7 Annotated Bibliography / 130
6 RF POWER METERS 131
6.1 RF Power Meter Basics / 131
6.2 Power Meter Sensors / 133
6.3 A Schottky Diode for Power Measurements in Cellular Phone
Systems / 134
6.4 The Power Meter Unit / 135
6.5 Power Meter Controls / 138
6.6 Annotated Bibliography / 138
7 FREQUENCY COUNTERS 139
7.1 Frequency Counter Operation / 139
7.2 Annotated Bibliography / 141
8 VNAs 143
8.1 What a VNA Does / 143
8.2 What a VNA Can Measure / 143
8.3 VNA Controls / 144
Dislay Control / 144
Channel Setup / 145
Trace Setup / 145
Entry Control / 147
8.4 VNA Display Notations / 147
8.5 Error Correction / 147
8.6 Example of VNA Measurements on an RF Part / 152
8.7 Swept Measurements on the VNA as a Function of Power / 154
8.8 Example Measurement Procedure Using the VNA / 157
Objective / 157
Measurements Being Demonstrated / 158
DUT Specifications / 161
Significance to Wireless System Performance / 161
Generic Procedure / 161
8.9 Annotated Bibliography / 165
viii CONTENTS
9 SPECTRUM ANALYZERS 167
9.1 Spectrum Analyzer Principles / 167
9.2 What a Spectrum Analyzer Can Measure / 168
9.3 Spectrum Analyzer Block Diagram / 170
9.4 Spectrum Analyzer Controls / 171
Center Frequency and Span / 171
Reference Level and Attenuation / 172
Resolution Bandwidth / 173
Video Bandwidth / 173
Markers / 175
9.5 Power Suite Measurements / 175
9.6 Basic Modulation Formats / 175
9.7 Example Spectrum Analyzer Operation and FM Spectrum
Measurement / 178
Objective / 178
FM Theory / 178
Measurements Being Demonstrated / 178
Generic Procedure / 178
9.8 Annotated Bibliography / 180
10 VSAs 183
10.1 What a VSA Does / 183
10.2 VSA Equipment / 183
10.3 What the VSA Can Measure / 185
10.4 Annotated Bibliography / 191
11 NOISE FIGURE METERS 193
11.1 Noise Figure Meter Setup / 193
11.2 Noise Figure Principles / 193
11.3 Annotated Bibliography / 197
12 COAXIAL CABLES AND CONNECTORS 199
12.1 Coaxial Connectors / 199
12.2 Cables and Connectors Best Practices / 200
12.3 Popular Coaxial Cable Connectors / 200
12.4 Coaxial Cables / 202
12.5 Annotated Bibliography / 202
CONTENTS ix
13 RF MEASUREMENT UNCERTAINTIES 203
13.1 Mismatch Uncertainties / 204
13.2 RF Power Meter Measurement Uncertainties / 205
Mismatch Uncertainties / 205
Calibration Factor Uncertainty / 207
Magnification and Offset / 207
13.3 Uncertainty of VNA Measurement of Absolute Power / 207
13.4 Uncertainty of Spectrum Analyzer Measurements / 210
Frequency Measurement Uncertainty / 210
Power Measurement Uncertainty / 210
Examples of Measurement Uncertainty of PSA 4440E Spectrum
Analyzer Under Different Measurement Conditions / 211
13.5 Measurement Uncertainties of Ratioed Measurements with a
VNA / 211
13.6 Noise Figure Measurement Uncertainty / 215
13.7 Annotated Bibliography / 216
14 COMPONENTS THAT DO NOT HAVE
COAXIAL CONNECTORS 219
14.1 Using SOLT Calibration Standards Fabricated in Microstrip / 220
14.2 TRL Standards in Microstrip / 222
14.3 De-Embedding / 222
14.4 Including the Fixture Effects as Part of the VNA Calibration / 223
14.5 Annotated Bibliography / 223
PART III MEASUREMENT OF INDIVIDUAL RF
COMPONENTS 225
15 RF COMMUNICATIONS SYSTEM BLOCK DIAGRAM 227
15.1 RF Communications System Components / 227
15.2 Annotated Bibliography / 232
16 SIGNAL CONTROL COMPONENTS 233
16.1 RF Semiconductors / 233
16.2 Electronically Controlled Attenuators and Switches / 236
16.3 Measurements of PIN Diode Attenuators and Switches / 240
16.4 Annotated Bibliography / 240
x CONTENTS
17 PLOs 241
17.1 Characteristics and Operation of a PLO / 241
17.2 Phase Noise and its Significance in a Digital RF
Communications System / 246
17.3 Characteristics of PLOs that Need to be Measured / 248
Frequency / 248
Tuning Sensitivity / 249
Power / 249
Phase Noise / 249
17.4 Example Procedure for Phase Noise Measurements of PLOs / 252
Measurements Being Described / 252
Specifications of PLO / 252
Significance to Wireless System Performance / 252
Generic Procedure / 252
17.5 Annotated Bibliography / 254
18 UPCONVERTERS 255
18.1 How an Upconverter Works / 255
18.2 Mathematical Theory of Upconverter and
Mixer Action / 257
18.3 Measurement of Upconverter Performance / 258
18.4 Generic Procedure for Upconverter Measurement / 261
18.5 Annotated Bibliography / 262
19 POWER AMPLIFIERS 263
19.1 RF Transistors / 263
19.2 Semiconductor Materials for RF Transistors / 264
19.3 Transistor Fabrication Processes / 265
MESFETs / 265
Bipolar Transistor / 268
HEMTs and HBTs / 270
LDMOS / 271
19.4 Modulation Distortion Caused by Power Amplifier
Nonlinearity / 272
19.5 Measurements to be Performed on RF Power Amplifiers / 278
19.6 Measurements of Amplifier Output Characteristics Versus Frequency
and Input Power / 278
19.7 Harmonic Power Measurements / 283
CONTENTS xi
19.8 Example Power Amp Measurements on the VNA / 284
Objective / 284
Measurements Being Demonstrated / 285
Specifications of Power Amplifier / 285
Generic Procedure / 285
19.9 Annotated Bibliography / 287
20 ANTENNAS 289
20.1 Antenna Functions / 289
Gain / 289
Pattern / 291
Gain / 292
Side Lobes / 292
Polarization / 292
Impedance Match / 293
Antenna Area / 293
20.2 Types of Antennas / 293
Half-Wave Dipole Antenna / 293
Patch Antenna / 295
Colinear Dipole Array / 296
Parabolic Dish Antennas / 297
Patch Antenna Array / 297
20.3 Measurement of Antennas / 299
20.4 Duplexers / 301
20.5 Annotated Bibliography / 302
21 RF RECEIVER REQUIREMENTS 303
21.1 Annotated Bibliography / 305
22 RF FILTERS 307
22.1 RF Filter Characteristics / 307
22.2 RF Filter Design / 308
22.3 Types of Filters / 309
Microstrip Filter / 309
Ceramic Block Filter / 309
Surface Acoustic Wave (SAW) Filters / 310
Film Bulk Acoustic Resonator (FBAR) Filters / 311
Base Station Filters / 312
xii CONTENTS
22.4 Measurement of RF Filters / 313
22.5 Group Delay and its Measurement / 314
22.6 Example Filter Measurement / 318
Objective / 318
Measurements Being Demonstrated / 318
Specifications of DUT / 318
Generic Procedure / 319
22.7 Annotated Bibliography / 319
23 LNAs 321
23.1 Thermal Noise / 322
23.2 Noise Figure Principles / 322
Noise Figure of Passive Components / 323
Cascaded Noise Figure / 324
Mismatching of the Transistor Input to
Reduce Noise Figure / 325
23.3 Intermodulation Products / 328
23.4 S-Parameters and How they are Used / 331
23.5 Example LNA Measurement on the VNA / 334
Objective / 334
Measurements Being Demonstrated / 335
Specifications of LNA / 335
Generic Procedure / 335
23.6 Annotated Bibliography / 344
24 MIXERS 345
24.1 Basic Mixer Performance / 345
24.2 Selection of Individual Voice and Data Channels / 349
24.3 The Removal of Image Noise / 350
24.4 ZIF Mixer / 351
24.5 Mixer Measurements / 353
24.6 Annotated Bibliography / 355
25 NOISE FIGURE MEASUREMENT 357
25.1 Noise Figure Measurement Setup
and Procedure / 357
25.2 Measurement of the Noise Figure and Gain of LNAs, Filters, and
Mixers / 358
CONTENTS xiii
25.3 Approximate Measurements of Noise Figure Without the NF
Hardware and Software / 363
25.4 Measurement of Noise Figure Contours on the
Smith Chart / 364
25.5 Annotated Bibliography / 364
26 INTERMODULATION PRODUCT MEASUREMENT 367
26.1 Intermodulation Products / 367
26.2 Third-Order Intercept Point / 369
26.3 Calculation of Maximum Input Power / 370
26.4 Cautions When Measuring Distortion Products / 371
26.5 Example Measurement for Intermodulation Products / 371
Objective / 371
Measurements Being Demonstrated / 372
Generic Procedure / 372
26.6 Annotated Bibliography / 373
27 OVERALL RECEIVER PERFORMANCE 375
27.1 Overall Performance of a Typical RF Receiver / 376
27.2 Formulas for Combining Gain, Noise Figure, and OIP3
of the Receiver Components / 379
27.3 Software for Calculation of Overall Receiver Performance / 379
27.4 Calculation of Overall Receiver Performance as a Function of Part
Temperature / 383
27.5 Switching the LNA Into and Out of the Overall Receiver / 384
27.6 Annotated Bibliography / 385
28 RFICs 387
28.1 Wireless LAN / 388
28.2 Four Band GSM, GPRS, EDGE Handset / 389
28.3 Annotated Bibliography / 392
PART IV TESTING OF DEVICES WITH DIGITALLY
MODULATED SIGNALS 393
29 WIRELESS COMMUNICATION SYSTEMS 395
29.1 Block Diagram of the Complete Wireless Communication
System / 396
29.2 Analog Voice and Video Signals / 398
xiv CONTENTS
29.3 The Digitizing of Analog Signals / 400
29.4 Data Signals / 403
29.5 Compression of Digital Voice and Data Signals / 404
Compression of Voice Signals / 404
Compression of Video Signals / 406
29.6 Error Correction / 407
29.7 Typical Bit Rates of
Communications Systems / 409
29.8 Packet Switching / 410
29.9 Annotated Bibliography / 411
30 MULTIPLE ACCESS TECHNIQUES: FDMA,
TDMA, AND CDMA 413
30.1 Frequency Division Multiple Access (FDMA) / 413
30.2 Time Division Multiple Access (TDMA) / 416
30.3 Code Division Multiple Access (CDMA) / 418
30.4 3G Cell Phones / 424
30.5 High Data Rate Systems for Cell Phones / 425
Cdma2000 Systems / 425
HSDPA High Data Rate Systems / 426
30.6 Measurement of the Distortion of Digitally Modulated Signals by
RF Components / 429
30.7 Annotated Bibliography / 429
31 OFDM, OFDMA, AND WiMAX 431
31.1 802.11 Specifications / 431
31.2 OFDM Multiple Access Principles / 433
31.3 WiMAX / 435
31.4 Annotated Bibliography / 437
32 ACP 439
32.1 ACP / 439
32.2 Measuring ACP / 440
32.3 ACP for North American Digital Cellular (NADC) Versus
GSM Modulation Formats / 440
32.4 Backoff / 441
32.5 ACP Measurement Results for NADC and GSM / 441
32.6 Zero Span / 443
32.7 Annotated Bibliography / 444
CONTENTS xv
33 CONSTELLATION, VECTOR, AND
EYE DIAGRAM AND EVM 445
33.1 Power Amplifier Backoff / 446
33.2 Constellation, Vector, and Eye Diagrams / 447
Constellation Diagram / 447
Vector Diagram / 447
Eye Diagram / 447
33.3 EVM / 451
EVM Troubleshooting / 451
EVM Versus Time / 451
EVM Spectrum / 451
IQ Modulator Impairments / 454
33.4 Measurements of Constellation, Vector, and Eye Diagrams
and EVM on an RF Power Amplifier and on an IF Filter / 454
33.5 EVM Trouble Shooting Tree / 463
33.6 Annotated Bibliography / 463
34 CCDF 465
34.1 CCDF Curves / 466
34.2 Derivation of CCDF Curves / 467
34.3 Comparison of Vector Diagrams and CCDF / 467
34.4 The Effect of the Number of Active Spread Spectrum Codes / 470
34.5 CCDF in Component Design / 470
34.6 Annotated Bibliography / 473
35 BER 475
35.1 BER (Bit Error Rate) Testing / 475
35.2 Annotated Bibliography / 477
36 MEASUREMENT OF GSM EVOLUTION COMPONENTS 479
36.1 Measurement of EDGE Signal Distortion / 481
36.2 Measurement of WCDMA and HSDPA Distortions / 482
36.3 Annotated Bibliography / 489
TERMINOLOGY 491
INDEX 497

FOREWORD
In the late 1960s as part of a technical seminar team, I traveled with HP’s firstgeneration
Automatic Network Analyzer (ANA), discussing and demonstrating
new measurements and s-parameter design techniques. One of our stops was at a
U.S. East Coast based defense organization, where a large group gathered to hear
our talk. At the conclusion, a man with a skeptical expression on his face indicated
that he had two questions. In a somewhat hostile manner he asked, “Are you
telling me that with this new equipment I can reliably characterize active devices at
microwave frequencies?” We assured him that for small-signal applications it was
true. Then he went on, “If I turn off the equipment today, and repeat my measurement
tomorrow, will I get the same data?” Again, we replied that after proper calibration, he
will have the same results. Shaking his head in disbelief he said, “I cannot believe
such b.s.,” and stormed out of the lecture hall.
It is hard to understand such a reaction today. However, until the introduction of
the network analyzer, obtaining reliable and repeatable y-parameter component
characterization with its predecessor, the General Radio RF Bridge, was not possible.
Without accurate data or component models, microwave circuit design was more of
an art than science.
Even after the spectrum analyzer, network analyzer, and modern power meters
became available, relatively simple gain, impedance, power, harmonic and twotone
intermodulation measurements represented a large percentage of microwave
testing. This is in sharp contrast to what test engineers and technicians face today,
working on products using a wide range of mixed-mode signal processing. In
addition, they have to understand and measure parameters, Bit Error Rate (BER),
constellation and eye diagrams, Adjacent Channel Power (ACP), just to mention a
xvii
few. They also have to be familiar with various digital modulation systems, including
analog concepts. Last but not least, in the globally competitive marketplace, measurements
must be performed rapidly and inexpensively.
The authors of this book based the contents on their extensive experience teaching
continuing education courses to practicing professionals of the RF and microwave
industries. Their course material is fine-tuned with the feedback provided by
course participants and constantly updated to keep up with changes in technology.
Measurements described in the book range from basic to advanced types, in addition
to reviewing the necessary technical background of cellular and wireless communication
systems. I am not aware of any other textbook having such a wealth of information,
written in a simple, easily understandable style, without constant use of
complex mathematics. Learning the techniques described in the book will elevate
the value of anyone working in the field.
LES BESSER
Besser Associates
Mountain View, CA

ACKNOWLEDGMENTS
We would like to thank all the organizations and people who helped make this book
possible.
The idea began when the Test and Measurement Division of Hewlett-Packard
offered Besser Associates the loan of a suite of RF test equipment for demonstration
in their RF classes. Besser Associates is the worldwide leader in RT training, having
trained over 40,000 engineers, technicians and managers in RF topics. We serve as
instructors for Besser Associates. So beginning in 1998, we began a demonstration
class on RF Measurements using the HP equipment.
When HP split off their Test and Measurement Equipment division to become
Agilent Technologies, Agilent continued the loan of RF test equipment ot Besser.
As the cellular phone and wireless data industry grew and became more technically
complicated, so did the test equipment. We are grateful to Susan Owen of Agilent for
continuing to support this ongoing relationship, which always allowed us access to
the latest models of their equipment. We would also like to thank Ben Zarlingo,
who offered extensive support and insight into the operation of the Vector
Signal Analyzer.
Many other companies, like Anritsu, Rhode and Schwartz, Aeroflex, and Keithley,
to name a few, also make excellent test equipment. Often they demonstrated their test
equipment in our course. Along these lines we enjoyed a great deal of support from
David Vondran of Anritsu corporation, who provided detailed background on the
Scorpion Network Analyzer and noise figure measurements. We did not try to
make comparisons between test equipments, but continued to conduct a course
using the Agilent equipment, because of their generosity in always loaning us the
xix
latest and best they had. This kept us busy learning how to operate their continually
evolving equipment, as the cell phone industry itself evolved.
The Besser RF Measurements course has continued to grow in popularity. Initially
we taught the five-day course a few times a year, then several times a year. Last year
(2007) we taught it 7 times. About a year ago, we decided to write this book, based on
the RF Measurements course.
We would also like to thank everyone at Besser Associates, Founder Dr. Les
Besser, President Jeff Lange, VP of Sales Annie Wong, and all the administrative
staff and instructors who helped and encouraged us to write this book. We would
also like to thank Allen Podell for providing numerous technical insights as well
as practical tips on keeping our fragile lab components in good repair.
Finally, we would like to thank all the engineers, technicians, and managers who
have taken our RF measurements course and made valuable suggestions on how to
make it better.
We hope you will enjoy our book and find it useful. We hope that it will improve
your understanding of RF measurements by at least 7 dB.
AL SCOTT
REX FROBENIUS

:11bb

:11bb

:11bb

[hide]

[/hide]

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:11bb :11bb :11bb :11bb

测量是工程中非常重要的步骤，只有测量准确了，才能体现出设计工作的成果

感谢楼主分享!!!!!!!!!!!!!!!

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感謝你了

看看实际的测量技术，又具有什么样的试验条件

看看实际的测量技术，又具有什么样的试验条件

本帖最后由 huangfeihong88 于 2009-10-21 19:07 编辑

:53bb

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不知道能不能看懂，貌似很艰深似的。

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本帖最后由 huangfeihong88 于 2009-10-21 19:11 编辑

:11bb :11bb

本帖最后由 huangfeihong88 于 2009-10-21 19:11 编辑

:27bb :27bb

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本帖最后由 huangfeihong88 于 2009-10-21 19:12 编辑

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本帖最后由 huangfeihong88 于 2009-10-21 19:12 编辑

:11bb :11bb

英文的看着有些头痛，先看看，谢谢楼主分享

不知道能不能看懂，貌似很艰深似的

看着内容挺不错的，下载抽空看看吧！多谢楼主发帖

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感謝樓主分享
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:11bb ......................

本帖最后由 huangfeihong88 于 2009-10-21 19:12 编辑

:11bb :27bb

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本帖最后由 huangfeihong88 于 2009-10-21 19:12 编辑

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本帖最后由 huangfeihong88 于 2009-10-21 19:12 编辑

:11bb :11bb

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本帖最后由 huangfeihong88 于 2009-10-21 19:13 编辑

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本帖最后由 huangfeihong88 于 2009-10-21 19:13 编辑

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内容挺不错的，下载抽空看看吧
好资料，谢谢分享！

本帖最后由 huangfeihong88 于 2009-10-21 19:13 编辑

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本帖最后由 huangfeihong88 于 2009-10-21 19:13 编辑

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本帖最后由 huangfeihong88 于 2009-10-21 19:13 编辑

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本帖最后由 huangfeihong88 于 2009-10-21 19:13 编辑

好东西! 谢谢楼主!! :11bb   :30bb

本帖最后由 huangfeihong88 于 2009-10-21 19:13 编辑

:31bb :11bb

赞，相当的不错~~~~~~对gsm可以有更深的理解。

貌似内容很不错，抽点时间瞧瞧。。。。。。。

本帖最后由 huangfeihong88 于 2009-10-21 19:14 编辑

好资料，谢谢分享! :31bb

本帖最后由 huangfeihong88 于 2009-10-21 19:14 编辑

:27bb :11bb

:11bb :11bb :11bb

本帖最后由 huangfeihong88 于 2009-10-21 19:15 编辑

:46bb

有很强实践性的资料啊 感谢分享:27bb

不错！谢谢楼主提供！:30bb :27bb

本帖最后由 huangfeihong88 于 2009-10-21 19:16 编辑

:27bb  :29bb

不错啊 很好的东西啊 支持啊

:27bb 7# 00d44

多谢楼主！

谢谢。。。。。。。。。。。。

本帖最后由 huangfeihong88 于 2009-10-21 19:16 编辑

:51bb

多谢~                   {:4_196:}

看上去想不错的东西

收下好好得咀嚼  感谢您的分享：9de

感谢楼主分享

4# 00d44
感謝！我們好好讀一下

谢谢楼主！！！

谢谢，原来我有一本，丢了，只好看电子版了！

好，看完它，标题  ）

本帖最后由 huangfeihong88 于 2009-10-21 19:16 编辑

:21bb:21bb

感謝樓主分享

看来不错，学习下看看。

不错的：17de

:46bb好东西啊！

超實用的電子書
感謝大大分享喔~~~

好东西，谢谢分享

:16bb:16bb

感谢!! 感谢!!

书很好啊。

no way to download

看着内容挺不错的，下载抽空看看吧！多谢楼主发帖

对这方面挺感兴趣 下载来看看

不知道能不能看懂，貌似很艰深似的

一共几部分 怎么我只看到两个压缩文件

谢谢了，真的是感人至深

谢谢楼主共享。。。。。。。。。。。。。。。

多谢楼主发帖{:6_924:}

谢谢楼主分享

管理员的资料也很多啊。

Thank you for your sharing.

{:7_1234:}

好资料，顶一下，下载下来看啊可能了

喜欢新书。。。。。。。。。

{:7_1234:}

多看英文书籍，提高阅读能力

谢谢楼主！

good good good good good good

很好，下来看看

谢谢慷慨的楼主

谢谢楼主了，学习学习

谢谢楼主了，学习学习

呵呵，是一本好书，:45bb

:53bb:50bb:46bb

不错的书哦！

好像挺新的啊

还差一个分卷，不过研发和测试都厉害才能解决实际问题。

好东西真多呀

顶老大，收藏

感謝大大分享

只看楼主发的前面的内容就知道这本书是RF的人必备。所以，三个字，必须拿下！

好好 啥好东西

kankanxian

加油加油加油加油加油加油

很棒的一本書阿
謝謝樓主的分享啊

不错

看看看啊看看啊看

内容挺不错

谢谢楼主的分享~~

还是原版的好。

谢谢楼主呢
正需要呢

好书，谢谢分享{:7_1234:}

谢谢LZ分享!

好资料！！

牛逼的资料

我肯定能看懂。

thanks a lot

fei chang gan xie~

Thanks a lot!....{:7_1259:}

RF.Measurements.for.Cellular.Phones.and.Wireless.Data.Systems.Jul.2008

回复只为看帖

{:7_1234:}

貌似比较高深,但是很想看看书里是怎么介绍天线这块的

haohaohao

多谢楼主。

感谢楼主分享

谢谢呆呆，

这什么东东？

好书，学习学习。

看着内容挺不错的，下载抽空看看吧！多谢楼主发帖！

谢谢分享

老大东西真多呀！！

给力了，谢谢楼主了。

好像不错啊

不错啊

thanks very much

好资料，谢谢分享！

感谢楼主分享

多谢老大分享...

实际的测量

还不错的一本关于RF测试的书

很好。，。。。。。

谢谢，学习一下再说

感谢楼主，强烈支持！

ура пиля.....

thanks for sharing

谢谢！看看。

好书～谢谢楼主～～

xxfx谢谢分享谢谢分享

谢谢分享

不知道能不能看懂

很好的资料 正需要看看

谢谢楼主了

谢谢分享

GOOD,THANKS!

下载备用，谢谢

谢谢楼主分享

ADS 2014 pill Out

E文的．．．我表示看不懂．．．嘻嘻

管理员的资料也很多啊。

RF.Measurements.for.Cellular.Phones.and.Wireless.Data.Systems.Jul.2008