Digital Filter
Technical Reference
Practical Considerations in Fixed-Point FIR Filter Implementations
s
Author
Date
Time
Rev
No.
Randy Yates
27–Mar–2007
16:25
PA3
n/a
1 (13)
Reference
fir.tex
Practical Considerations in Fixed-Point FIR Filter Implementations
Randy Yates
27–Mar–2007
s signal processi ng systems
http://www.digitalsignallabs.com
A
Typeset using LTEX 2ε
Digital Signal Labs
Public Information
Technical Reference
Practical Considerations in Fixed-Point FIR Filter Implementations
s
Author
Date
Time
Rev
No.
Randy Yates
27–Mar–2007
16:25
PA3
n/a
2 (13)
Reference
fir.tex
Contents
1 Introduction
1.1 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2 Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3
3
3
2 Scaling FIR Coefficients
4
3 Choosing the FIR Filter Output Word
4 Quantization Noise in FIR Filters
4.1 Truncation . . . . . . . . . . .
4.2 Rounding . . . . . . . . . . .
4.3 Dithering . . . . . . . . . . .
4.4 Noise-shaping . . . . . . . . .
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5 Conclusions
12
Practical Considerations in Fixed-Point FIR Filter Implementations
s
Author
Date
Time
Rev
No.
Randy Yates
27–Mar–2007
16:25
PA3
n/a
1 (13)
Reference
fir.tex
Practical Considerations in Fixed-Point FIR Filter Implementations
Randy Yates
27–Mar–2007
s signal processi ng systems
http://www.digitalsignallabs.com
A
Typeset using LTEX 2ε
Digital Signal Labs
Public Information
Technical Reference
Practical Considerations in Fixed-Point FIR Filter Implementations
s
Author
Date
Time
Rev
No.
Randy Yates
27–Mar–2007
16:25
PA3
n/a
2 (13)
Reference
fir.tex
Contents
1 Introduction
1.1 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2 Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3
3
3
2 Scaling FIR Coefficients
4
3 Choosing the FIR Filter Output Word
4 Quantization Noise in FIR Filters
4.1 Truncation . . . . . . . . . . .
4.2 Rounding . . . . . . . . . . .
4.3 Dithering . . . . . . . . . . .
4.4 Noise-shaping . . . . . . . . .
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5 Conclusions
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References: [1] R. Yates, “Fixed-Point Arithmetic: An Introduction.” Digital Signal Labs Public Information