Download presentation
Presentation is loading. Please wait.
1
A New Approach to Pipeline FFT Processor
Speaker: Group B3 B 徐誠羿 B 高翊軒 Adviser: Prof. An-Yeu Wu Date:
2
Outline DFT FFT Previous pipeline FFT processor architectures
New FFT processor radix-22 Comparison New FFT processor Radix-23 Conclusion Simulation References
3
DFT Definition of Discrete Fourier Transform and Inverse DFT.
4
FFT An algorithm which computes DFT. A method of multiplying Discrete Fourier Transform. Concept: Divide and conquer. points only (using butterfly structure)
5
Previous Pipeline FFT Processor Architectures
R2MDC( Radix-2 Multi-path Delay Commutator )
6
R4MDC(Radix-4 Multi-path Delay Commutator)
R4SDC(Radix-4 Single-path Delay Commutator)
7
Radix-2 (Radix-2 Single-path Delay Feedback)
DIT (bit reverse->normal) DIF (normal->bit reverse)
8
Radix-2(cont.)
9
Radix-4(Radix-4 Single-path Delay Feedback)
multipliers
10
Ideal Architecture Minimum multipliers Minimum adders
Minimum memory size
11
New FFT processor radix-22
It has the same multiplicative complexity as radix-4 algorithm, but retain butterfly structure of radix-2 algorithm. For length-N DFT compution, it requires: complex multipliers complex data memory -> minimum in the above processor
12
Derivation
13
Point Flow
14
BF Picture
15
Radix-22
16
BF2i and BF2ii Structure
17
Hardware Comparison multiplier Memory size R2MDC 2( ) R2SDF N-1 R4 SDF
2( ) R2SDF N-1 R4 SDF R4MDC 3( ) R4SDC 2N-2 R SDF adder 4 8 3
18
Simulation Input x(n) = n + n*j , n=[0,63]
19
Simulation(Comparison)
Compare with MATLAB FFT
20
Conclusion Radix-22;multiplicitive complexity => Radix-4.
butterfly structure => Radix-2. Use single delay feedback. Using fixed points arithmetic and a complex array multiplier. An ideal architecture for VLSI implementation of pipeline FFT processors.
21
New FFT Processor Radix-23(1/4)
It has the same multiplicative complexity as radix-8 algorithm, but retain butterfly structure of radix-2 algorithm. Faster and smaller than radix-2 and radix-22 . Combine radix-8 and radix-2. multiplier only.
22
New FFT Processor Radix-23(2/4)
23
New FFT Processor Radix-23(3/4)
24
New FFT Processor Radix-23 (4/4)
25
Reference Alan V.Oppenheim, Ronald W.Schafer, “Discrete-time signal processing” 2nd edition. Shousheng He and Trkelson, M.,”A new approach to pipeline FFT processor,” Procesdings of IPPS’96, April 1996, pp Signals and system. Chen.. Signals and system. Haykin.1st edition. OFDM Radix 23 website .hsu.cc.orz Discrete Signal processing.4th ed
26
Thank you
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.