Preface |
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xi | |
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1 | (14) |
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1.1 The discrete Fourier transform |
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1 | (1) |
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1.2 A brief historical background |
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2 | (2) |
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1.3 The scope of the present book |
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4 | (1) |
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1.4 Overview of the following chapters |
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5 | (2) |
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1.5 About the graphic presentation of sampled signals and discrete data |
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7 | (6) |
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1.5.5 Graphic presentations in the ID case |
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7 | (1) |
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1.5.5 Graphic presentations in the 2D case |
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8 | (5) |
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1.5.5 Graphic presentations in the MD case |
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13 | (1) |
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1.6 About the exercises and the internet site |
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13 | (2) |
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2 Background and basic notions |
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15 | (30) |
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15 | (1) |
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2.2 The continuous Fourier transform: definitions and notations |
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15 | (2) |
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2.3 The discrete Fourier transform: definitions and notations |
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17 | (4) |
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2.4 Rules for deriving new Fourier transforms from already known ones |
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21 | (10) |
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2.4.4 Rules for the ID continuous Fourier transform |
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22 | (1) |
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2.4.4 Rules for the 2D continuous Fourier transform |
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23 | (2) |
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2.4.4 Rules for the MD continuous Fourier transform |
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25 | (1) |
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2.4.4 Rules for the ID discrete Fourier transform |
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26 | (2) |
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2.4.4 Rules for the 2D discrete Fourier transform |
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28 | (1) |
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2.4.4 Rules for the MD discrete Fourier transform |
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29 | (2) |
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2.5 Graphical development of the DFT - a three-stage process |
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31 | (5) |
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2.6 DFT as an approximation to the continuous Fourier transform |
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36 | (5) |
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2.7 The use of DFT in the case of periodic or almost-periodic functions |
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41 | (4) |
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42 | (3) |
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3 Data reorganizations for the DFT and the IDFT |
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45 | (24) |
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45 | (1) |
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3.2 Reorganization of the output data of the DFT |
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45 | (2) |
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3.3 Reorganization of the input data of the DFT |
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47 | (4) |
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3.4 Data reorganizations in the case of IDFT |
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51 | (3) |
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54 | (6) |
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60 | (9) |
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66 | (3) |
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4 True units along the axes when plotting the DFT |
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69 | (20) |
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69 | (1) |
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4.2 True units for the input array |
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69 | (3) |
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4.3 True units for the output array |
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72 | (6) |
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4.3.3 The particular case of periodic functions |
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74 | (4) |
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4.4 True units for the DFT element values (heights along the vertical axis) |
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78 | (1) |
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79 | (10) |
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84 | (5) |
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5 Issues related to aliasing |
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89 | (54) |
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89 | (1) |
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5.2 Aliasing in the one dimensional case |
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89 | (6) |
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5.3 Examples of aliasing in the one dimensional case |
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95 | (18) |
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5.4 Aliasing in two or more dimensions |
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113 | (1) |
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5.5 Examples of aliasing in the multidimensional case |
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114 | (18) |
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132 | (1) |
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5.7 Signal-domain aliasing |
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133 | (10) |
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136 | (7) |
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6 Issues related to leakage |
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143 | (42) |
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143 | (1) |
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6.2 Leakage in the one dimensional case |
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143 | (5) |
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6.3 Examples of leakage in the one dimensional case |
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148 | (10) |
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6.4 Errors due to signal-domain truncation |
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158 | (4) |
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6.5 Spectral impulses that fall between output array elements |
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162 | (3) |
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6.6 Leakage in two or more dimensions |
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165 | (9) |
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6.6.6 The case of 2D 1-fold periodic functions |
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170 | (2) |
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6.6.6 The case of 2D 2-fold periodic functions |
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172 | (1) |
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6.6.6 The general MD case |
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173 | (1) |
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6.7 Signal-domain leakage |
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174 | (11) |
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179 | (6) |
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7 Issues related to resolution and range |
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185 | (10) |
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185 | (1) |
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7.2 The choice of the array size |
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185 | (1) |
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7.3 The choice of the sampling interval |
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186 | (1) |
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7.4 The choice of the sampling range |
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187 | (2) |
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7.5 The choice of the frequency step and of the frequency range |
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189 | (6) |
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192 | (3) |
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195 | (52) |
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195 | (1) |
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8.2 Representation of discontinuities |
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195 | (7) |
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202 | (1) |
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8.4 Symmetry related issues |
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203 | (7) |
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8.5 Jaggies on sharp edges as aliasing or reconstruction phenomena |
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210 | (13) |
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8.6 Sub-Nyquist artifacts |
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223 | (18) |
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8.7 Displaying considerations |
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241 | (1) |
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8.8 Numeric precision considerations |
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241 | (6) |
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242 | (5) |
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A Impulses in the continuous and discrete worlds |
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247 | (18) |
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247 | (1) |
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A.2 Continuous-world impulses vs. discrete-world impulses |
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247 | (1) |
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A. 3 Impulses in the spectral domain |
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248 | (11) |
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A.4 Impulses in the signal domain |
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259 | (6) |
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B Data extensions and their effects on the DFT results |
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265 | (8) |
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265 | (1) |
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B.2 Method 1: Extending the input data by adding new values beyond the original range |
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265 | (1) |
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B.3 Method 2: Extending the input data by denser sampling within the original range |
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266 | (2) |
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B.4 Method 3: Extending the input data by adding zeroes after each value (zero packing) |
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268 | (1) |
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B.5 Method 4: Extending the input data by replicating it |
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269 | (1) |
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B.6 Method 5: Extending the input data by replicating each of its elements |
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269 | (1) |
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B.7 Method 6: Extending the input data by adding zeroes beyond its original range (zero padding) |
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270 | (2) |
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272 | (1) |
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C The roles of p and q and their interconnections |
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273 | (26) |
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273 | (1) |
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C.2 The one dimensional case |
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273 | (7) |
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C.3 Generalization of p and q to the multidimensional case |
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280 | (19) |
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C.3.1 Multidimensional generalization in the continuous world |
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281 | (4) |
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C.3.2 Multidimensional generalization in the discrete world |
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285 | (14) |
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D Miscellaneous remarks and derivations |
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299 | (36) |
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D.1 The periodicity of the input and output arrays of the DFT |
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299 | (1) |
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D.2 Explanation of the element order in the DFT output array |
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300 | (2) |
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D.3 The beating effect in a sum of cosines with similar frequencies |
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302 | (4) |
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D.4 Convolutions with a sine function which have no effect |
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306 | (1) |
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D.5 The convolution of a square pulse with a sine function |
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307 | (3) |
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D.6 A more detailed discussion on Remark A.2 of Sec. A.3 |
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310 | (4) |
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D.7 The effect of the sine lobes on its convolution with a sharp-edged function |
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314 | (1) |
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D.8 On the order of applying the sampling and truncation operations |
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315 | (2) |
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D.9 Relation of the DFT to the CFT and to Fourier series |
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317 | (15) |
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D.9.1 Examples illustrating the relation of the DFT to the CFT and to Fourier series |
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325 | (7) |
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D.10 The 2D spectrum of a rotated bar passing through the origin |
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332 | (3) |
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E Glossary of the main terms |
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335 | (18) |
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335 | (1) |
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E.2 Terms in the signal domain |
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336 | (5) |
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E.3 Terms in the spectral domain |
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341 | (4) |
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345 | (8) |
List of the main relations |
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353 | (2) |
List of notations and symbols |
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355 | (4) |
List of abbreviations |
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359 | (2) |
References |
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361 | (6) |
Index |
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367 | |