Causal FIR filter€ y n[ ]€ x n[ ]Causal FIR filterQ:What is the definition of an FIR filter?Causal FIR filter€ y n[ ]€ x n[ ]Causal FIR filterQ:What is the definition of an FIR filter?A: The output y at each sample n is a weighted sum of the present input, x[n], and past inputs, x[n-1], x[n-2],…, x[n-M].Causal FIR filter€ y n[ ]€ x n[ ]Causal FIR filterQ:What is the formula for an FIR filter?Causal FIR filter€ y n[ ]€ x n[ ]Causal FIR filterQ:What is the formula for an FIR filter? € y n[ ]= b0x n[ ]+ b1x n −1[ ]+ K + bMx n − M[ ]€ y n[ ]= bkx n − k[ ]k= 0M∑Causal FIR filter€ n x n[ ]−2 0−1 00 11 02 03 0 € b0= 1,b1= 3,b2= 1€ y n[ ]= ?€ x n[ ]=δn[ ]-2 -1 0 1 2 3 4 500.10.20.30.40.50.60.70.80.91nx[n]TextEnd€ h n[ ]= ?€ y 1[ ]= ?€ y n[ ]= ?-2 -1 0 1 2 3 4 500.511.522.53ny[n]TextEndCausal FIR filter€ n x n[ ]−2 0−1 00 11 02 03 0 € b0= 1,b1= 3,b2= 1€ y n[ ]= 1x n[ ]+ 3x n −1[ ]+1x n − 2[ ]€ x n[ ]=δn[ ]€ h n[ ]= y n[ ]x[ n ]=δ[ n]€ y[n]001310 b0b1b2-2 -1 0 1 2 3 4 500.10.20.30.40.50.60.70.80.91nx[n]TextEnd€ h 1[ ]= 1δ1[ ]+ 3δ1−1[ ]+1δ1− 2[ ]€ h 1[ ]= 1δ1[ ]+ 3δ0[ ]+1δ−1[ ]€ h 1[ ]= 1 0( )+ 3 1( )+1 0( )€ h[n] = y n[ ]= 1δn[ ]+ 3δn −1[ ]+1δn − 2[ ]€ h 1[ ]= 3€ h n[ ]= bnh[0]=b0h[1]=b1h[2]=b2Causal FIR filter€ b0,b1,b2€ x n[ ]€ y n[ ]€ h n[ ]= bn€ y n[ ]= bkx n − k[ ]k= 0M∑€ y n[ ]= h[k]x n − k[ ]k=0M∑€ y n[ ]= h[n]* x[n]€ h[n]Convolution ofimpulse responseand inputweighted sum ofdelayed inputsCausal FIR filter€ n x n[ ]0 01 0.882 −0.843 −0.064 0.905 −0.81 € b0= 1,b1= 3,b2= 1€ y 3[ ]= ?0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5-1-0.8-0.6-0.4-0.200.20.40.60.81nx[n]TextEnd€ x[n] =sin 2π⋅ 0.33n( )u[n]€ h[n] = 1, 3,1[ ]€ y n[ ]= ?Causal FIR filter€ n x n[ ]0 01 0.882 −0.843 −0.064 0.905 −0.81 € b0= 1,b1= 3,b2= 1€ y n[ ]= 1x n[ ]+ 3x n −1[ ]+1x n − 2[ ]€ n y n[ ]0 01 0.882 1.783 −1.724 −0.135 1.84 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5-1-0.8-0.6-0.4-0.200.20.40.60.81nx[n]TextEnd0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5-2-1.5-1-0.500.511.52ny[n]TextEnd€ x[n] =sin 2π⋅ 0.33n( )u[n]€ y 3[ ]= 1x 3[ ]+ 3x 3 −1[ ]+1x 3 − 2[ ]€ y 3[ ]= 1x 3[ ]+ 3x 2[ ]+1x 1[ ]€ y 3[ ]= 1 −0.06( )+ 3 −0.84( )+1 0.88( )€ y 3[ ]= −1.72€ h[n] = 1, 3,1[ ]€ y n[ ]= bkx n − k[ ]k=0M∑= h[k]x n − k[ ]k=0M∑-2 -1 0 1 2 3 4 5-1-0.500.51nx[n]TextEnd-2 -1 0 1 2 3 4 50123nh[-n]TextEnd-2 -1 0 1 2 3 4 5-1-0.500.51ny[n]TextEnd€ y n[ ]= x n − 2[ ]h[n − (n − 2)]+ x n −1[ ]h[n − (n −1)]+ x[n]h n − n[ ]€ y n[ ]= h[n]* x[n] = x[n]* h[n]-2 -1 0 1 2 3 4 5-1-0.500.51nx[n]TextEnd-2 -1 0 1 2 3 4 500.511.522.53nh[-n]TextEndh[0]=b0h[1]=b1h[2]= b2€ y n[ ]= h[k]x n − k[ ]k=0M∑€ y n[ ]= h[0]x n[ ]+ h[1]x n −1[ ]+ h[2]x n − 2[ ]flipshiftmultiplysumGraphical Convolution€ = x[k]h n − k[ ]k=−∞∞∑flipb1=3b2=1b0=1-2 -1 0 1 2 3 4 5-1-0.500.51nx[n]TextEnd-2 -1 0 1 2 3 4 50123nh[-n]TextEnd-2 -1 0 1 2 3 4 5-1-0.500.51ny[n]TextEnd€ y n[ ]= x[k]h n − k[ ]k=− M0∑flipshiftmultiplysumGraphical Convolutionflip/shift by nmultiplysum€ y 0[ ]= x −2[ ]h[2]+ x −1[ ]h[1]+ x[0]h 0[ ]n=00000€ = 0( )1+ 0( )3+ 0( )1 = 0b1=3b2=1b0=1-2 -1 0 1 2 3 4 5-1-0.500.51nx[n]TextEnd-2 -1 0 1 2 3 4 50123nh[-n]TextEnd-2 -1 0 1 2 3 4 5-2-1012ny[n]TextEndflipshiftmultiplysumGraphical Convolutionflip/shift by nmultiplysum€ y n[ ]= x[k]h n − k[ ]k=− M0∑€ y 1[ ]= x −1[ ]h[2]+ x 0[ ]h[1]+ x[1]h 0[ ]n=10.8800b1=3b2=1b0=10.88€ = 0( )1+ 0( )3+ 0.88( )1 = 0.88-2 -1 0 1 2 3 4 5-1-0.500.51nx[n]TextEnd-2 -1 0 1 2 3 4 50123nh[-n]TextEnd-2 -1 0 1 2 3 4 5-2-1012ny[n]TextEndflipshiftmultiplysumGraphical Convolutionb1=3b2=1b0=1flip/shift by nmultiplysum€ y n[ ]= x[k]h n − k[ ]k=− M0∑€ y 2[ ]= x 0( )[ ]h[2]+ x 1[ ]h[1]+ x[2]h 0[ ]n=20.88-0.8401.78€ = 0( )1+ 0.88( )3+ −0.84( )1 = 1.78-2 -1 0 1 2 3 4 5-1-0.500.51nx[n]TextEnd-2 -1 0 1 2 3 4 50123nh[-n]TextEnd-2 -1 0 1 2 3 4 5-2-1012ny[n]TextEndflipshiftmultiplysumGraphical Convolutionb1=3b2=1b0=1flip/shift by nmultiplysum€ y n[ ]= x[k]h n − k[ ]k=− M0∑€ y 3[ ]= x 1[ ]h[2]+ x 2[ ]h[1]+ x[3]h 0[ ]n=30.88-0.84-0.06-1.71€ = 0.88( )1+ −0.84( )3+ −0.06( )1 = −1.72-2 -1 0 1 2 3 4 5-1-0.500.51nx[n]TextEnd-2 -1 0 1 2 3 4 50123nh[n]TextEnd-2 -1 0 1 2 3 4 5-2-1012ny[n]TextEndGraphical Convolutionb1b0b2€ y n[ ]= x[k]h n − k[ ]k=− M0∑€ y n[ ]= x[k]* h[k]Graphical convolution by decomposition€ x[n] =δ[n]-2 -1 0 1 2 3 4 500.511.522.53ny[n]TextEnd-2 -1 0 1 2 3 4 500.10.20.30.40.50.60.70.80.91nx[n]TextEndh[0]=b0h[1]=b1h[2]=b21. Remember impulse response € h[n] = b0δn[ ]+ b1δn −1[ ]+ b2δn − 2[ ]€ b0,b1,b2€ h[n]causal FIR filterGraphical convolution by decomposition€ x[n] = sin 2π⋅ 0.33n( )u[n]2. Decompose input into sum of scaled delayed impulses-2 -1 0 1 2 3 4 5-1-0.8-0.6-0.4-0.200.20.40.60.81nx[n]TextEnd-2 -1 0 1 2 3 4 5-202nx[1]TextEnd-2 -1 0 1 2 3 4 5-202nx[2]TextEnd-2 -1 0 1 2 3 4 5-202nx[3]TextEnd-2 -1 0 1 2 3 4 5-202nx[4]TextEnd-2 -1 0 1 2 3 4 5-202nx[5]TextEnd€ x[n] = 0.88δn −1[ ]− 0.84δn − 2[ ]− 0.06δn − 3[ ]+ 0.90δn − 4[ ]− 0.81δn − 5[ ]Input as impulsesInput-2 -1 0 1 2 3 4 5 6 7-202nx[1]h[n-1]TextEnd-2 -1 0 1 2 3 4 5 6 7-202nx[2]h[n-2]TextEnd-2 -1 0 1 2 3 4 5 6 7-202nx[3]h[n-3]TextEnd-2 -1 0 1 2 3 4 5 6 7-202nx[4]h[n-4]TextEnd-2 -1 0 1 2 3 4 5 6 7-202nx[5]h[n-5]TextEndGraphical convolution by decomposition3. find impulse responses to each impulse-2 -1 0 1 2 3 4 5-202nx[1]TextEnd-2 -1 0 1 2 3 4 5-202nx[2]TextEnd-2 -1 0 1 2 3 4 5-202nx[3]TextEnd-2 -1 0 1 2 3 4 5-202nx[4]TextEnd-2 -1 0 1 2 3 4 5-202nx[5]TextEnd€ y1[n] = 0.88 h[n −1]( )€ y2[n] = −0.84 h[n − 2]( )€ y3[n] = −0.06 h[n − 3]( )€ y4[n] = −0.06 h[n − 4]( )€ y5[n] = −0.81 h[n …
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