Sample Rate Conversion in Software Configurable Radios (Artech House Mobile Communications Series)

284 Pages·2002·2.17 MB·English

by  Tim Hentschel

Sample Rate Conversion in
Software Configurable Radios
Fora listing of recenttitles in the Artech House MobileCommunicationsSeries,
turn to theback of this book.
Sample Rate Conversion in
Software Configurable Radios
Tim Hentschel
Artech House
Boston London
*
www.artechhouse.com
iv Sample RateConversion inSoftware ConfigurableRadios
LibraryofCongressCataloging-in-PublicationData
Hentschel,Tim.
Samplerateconversioninsoftwareconfigurableradios/TimHentschel.
p.cm.—(ArtechHousemobilecommunicationsseries)
Includesbibliographicalreferencesandindex.
ISBN1-58053-336-1(alk.paper)
1.Softwareradio. 2.Telecommunication—Traffic—Management.
3.Sampling(Statistics). I.Title. II.Series.
TK5103.4875.H452002
621.384—dc21 2002074697
BritishLibraryCataloguinginPublicationData
Hentschel,Tim
Samplerateconversioninsoftwareconfigurableradios.—(ArtechHousemobile
communicationsseries)
1.Signalprocessing—Digitaltechniques 2.Digitalfilters(Mathematical)
3.Sampling(Statistics) 4.Mobilecommunicationsystems 5.Radio—Receiversand
reception
I.Title
621.3’822
ISBN1-58053-336-1
CoverdesignbyGaryRagaglia
(cid:1)2002ARTECHHOUSE,INC.
685CantonStreet
Norwood,MA02062
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Alltermsmentionedinthisbookthatareknowntobetrademarksorservicemarkshave
been appropriately capitalized. Artech House cannot attest to the accuracy of this
information. Use of a term in this book should not be regarded as affecting the validity of
anytrademarkorservicemark.
InternationalStandardBookNumber:1-58053-336-1
LibraryofCongressCatalogCardNumber:2002074697
10 9 8 7 6 5 4 3 2 1
Contents v
Contents
Preface xi
1 Sample Rate Conversion in the
Context of Software Radio 1
1.1 Introduction 1
1.2 Software Radio 1
1.3 Critical Functionality of a Software Radio
Terminal 7
1.3.1 Analog-to-Digital Conversion 7
1.3.2 SRC 20
1.3.3 Channelization 22
1.3.4 Application of SRC 25
1.3.5 Summary and Conclusion 25
References 26
2 Basic Principles of SRC and
Multirate Systems 29
2.1 Introduction 29
2.2 Basic Considerations of SRC 30
2.2.1 Resampling After Reconstruction 30
2.2.2 Irrational Factor SRC 38
2.2.3 Rational Factor SRC 43
v
vi Sample RateConversion inSoftware ConfigurableRadios
2.2.4 Integer Factor SRC 45
2.2.5 Up- and Downsampling with Phase Offset 52
2.2.6 Polyphase Decomposition 55
2.2.7 Modulation Representation 60
2.2.8 Summary 61
2.3 Linear Periodically Time-Varying Systems
and Block Filtering 61
2.3.1 Introductory Remarks 61
2.3.2 The Raising Procedure 62
2.3.3 Block-Filtering and Multirate Systems 71
2.3.4 Frequency Behavior of Multirate Systems:
The Bifrequency Approach 76
2.3.5 Summary 82
References 82
3 A Concept for SRC in Software
Radio Terminals 85
3.1 Introduction 85
3.2 Review of the OSR of a Signal 85
3.3 The Conversion Factor: Integer Factor
and Fractional SRC 86
3.4 Processing Issues 89
3.5 Summary 95
References 96
4 Systems for Integer Factor SRC 99
4.1 Introduction: The Direct Approach 99
4.2 Parallelization: Polyphase Filters 100
4.2.1 Introductory Remarks 100
4.2.2 Increasing the Sample Rate 100
Contents vii
4.2.3 Reducing the Sample Rate 106
4.2.4 Reducing the Size of the Coefficient Memory 110
4.3 Efficient Realization of FIR Filters on
Periodically Time-Varying Systems 113
4.3.1 Computing All Coefficients from One
Polyphase Component 113
4.3.2 Storing More Than One Polyphase
Component 124
4.3.3 Alternative Interpretation of Polynomial
Polyphase Filters 133
4.4 Conclusion 141
References 141
5 Comb Filters: Special Systems for
Integer Factor SRC 143
5.1 Introduction 143
5.2 Basic Considerations of Comb Filters 143
5.3 Cascaded Comb Filters 145
5.4 CIC Filters 147
5.4.1 The Structure of CIC Filters 147
5.4.2 Noise Shaping with CIC Decimators 149
5.4.3 CIC Interpolators 152
5.4.4 The Frequency-Sampling Structure of
FIR-Filters 152
5.4.5 Raising a CIC Decimator 153
5.5 Recursive Multirate Filters 155
5.5.1 The Idea of Recursive Multirate Filters 155
5.5.2 A Second-Order Decimator 156
5.5.3 A Second-Order Interpolator 158
5.5.4 Higher-Order Structures 161
5.5.5 Higher-Order Integrate and Dump 164
viii SampleRate Conversionin SoftwareConfigurable Radios
5.6 Generalizing Recursive Multirate Filters 165
5.6.1 Motivation 165
5.6.2 Arbitrary Poles of the Filter GðzÞ 165
5.6.3 Designing Generalized Recursive Multirate
Filters 172
5.7 Conclusion 185
References 185
6 Systems for Fractional SRC 187
6.1 Introduction: The Direct Approach 187
6.2 Polyphase and Block Realization 188
6.2.1 Block Filtering and Conventional Polyphase
Structures 188
6.2.2 Time-Varying Polyphase Structures 191
6.3 Time-Varying CIC Filters 197
6.3.1 CIC Filters for Fractional SRC 197
6.3.2 State-Space Equations 198
6.3.3 Simplification of the State Equation 204
6.4 A Note on Irrational Factor SRC 208
6.5 Summary 209
References 210
7 Applications of SRC 211
7.1 Introduction 211
7.2 Scenario of the Application 212
7.3 Requirements on SRC in the
Context of Mobile Communications 213
7.4 Conventional Filters 216
7.4.1 Direct Implementation 216
7.4.2 Direct-Block Implementation 217
Contents ix
7.4.3 Time-Varying Polyphase/Block
Implementation 217
7.4.4 Filter Characteristics 218
7.4.5 Conclusion 219
7.5 Polynomial Filters 219
7.5.1 Review 219
7.5.2 The Conventional and Transposed
Farrow Structures 220
7.5.3 The Generalized (Time-Varying) Conventional
Farrow Structure and the Transposed
Farrow Structure 224
7.5.4 Antialiasing with the Generalized
Conventional Farrow Structure 226
7.5.5 Conclusion 229
7.6 Time-Varying CIC Filters 229
7.7 Comparison of Methods for SRC 230
7.8 Summary 232
References 232
8 Conclusions 235
8.1 Summary 235
8.2 SRC Questionnaire 237
Appendix:
Derivations and Calculations 239
A.1 Polyphase Decomposition of the
Transfer Function 239
A.2 The Modulation Representation 241
A.3 The Raising Procedure 243
A.3.1 The State-Space Description of Raised
Systems 243