Hi there,
I have a 1024 coef FIR filter bank, which I use to filter a cosine
signal. I have calculated the stop-band supression to be -35dBs but
this sounds really high to me. The filters turning point is at 0.1f,
where f is the sampling frequency. For example, if I feed the FIR with
a frequency of 0.25f, I get a signal out with amplitude 1*10^-6. Does
this sound correct?
Is there a function in matlab I could use to plot the spectrum
resulting from my FIR?
Thanks,
Aine.
My Coefs-
0.000029f,-0.000000f,-0.000029f,-0.000048f,-0.000048f,0.000030f,0.000000f,
0.000030f,0.000049f,0.000049f,0.000030f,0.000000f,-0.000031f,-0.000050f,
-0.000050f,-0.000031f,-0.000000f,0.000031f,0.000051f,0.000051f,0.000032f,
-0.000000f,-0.000032f,-0.000053f,-0.000053f,-0.000033f,0.000000f,0.000034f,
0.000055f,0.000055f,0.000034f,-0.000000f,-0.000035f,-0.000057f,-0.000057f,
-0.000036f,0.000000f,0.000036f,0.000060f,0.000060f,0.000038f,0.000000f,
-0.000038f,-0.000063f,-0.000063f,-0.000039f,0.000000f,0.000040f,0.000066f,
0.000066f,0.000042f,-0.000000f,-0.000042f,-0.000069f,-0.000070f,-0.000044f,
0.000000f,0.000045f,0.000073f,0.000074f,0.000046f,-0.000000f,-0.000047f,
-0.000078f,-0.000079f,-0.000049f,-0.000000f,0.000050f,0.000082f,0.000083f,
0.000052f,-0.000000f,-0.000053f,-0.000088f,-0.000089f,-0.000055f,0.000000f,
0.000057f,0.000093f,0.000094f,0.000059f,-0.000000f,-0.000060f,-0.000099f,
-0.000100f,-0.000063f,0.000000f,0.000064f,0.000105f,0.000106f,0.000067f,
0.000000f,-0.000068f,-0.000112f,-0.000113f,-0.000071f,-0.000000f,0.000073f,
0.000119f,0.000120f,0.000075f,-0.000000f,-0.000077f,-0.000127f,-0.000128f,
-0.000080f,0.000000f,0.000082f,0.000135f,0.000136f,0.000085f,-0.000000f,
-0.000087f,-0.000143f,-0.000145f,-0.000091f,-0.000000f,0.000093f,0.000152f,
0.000154f,0.000096f,-0.000000f,-0.000099f,-0.000161f,-0.000163f,-0.000102f,
0.000000f,0.000105f,0.000171f,0.000173f,0.000108f,-0.000000f,-0.000111f,
-0.000182f,-0.000184f,-0.000115f,0.000000f,0.000118f,0.000193f,0.000195f,
0.000122f,-0.000000f,-0.000125f,-0.000204f,-0.000207f,-0.000129f,0.000000f,
0.000132f,0.000216f,0.000219f,0.000137f,-0.000000f,-0.000140f,-0.000229f,
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0.000270f,0.000273f,0.000171f,0.000000f,-0.000174f,-0.000285f,-0.000288f,
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0.000337f,0.000211f,-0.000000f,-0.000215f,-0.000351f,-0.000355f,-0.000222f,
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0.000258f,-0.000000f,-0.000263f,-0.000429f,-0.000434f,-0.000271f,0.000000f,
0.000276f,0.000451f,0.000455f,0.000284f,0.000000f,-0.000290f,-0.000473f,
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0.000546f,0.000551f,0.000344f,-0.000000f,-0.000350f,-0.000572f,-0.000577f,
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0.000000f,0.000440f,0.000718f,0.000725f,0.000452f,-0.000000f,-0.000460f,
-0.000751f,-0.000758f,-0.000473f,-0.000000f,0.000481f,0.000786f,0.000793f,
0.000494f,-0.000000f,-0.000503f,-0.000821f,-0.000829f,-0.000517f,0.000000f,
0.000526f,0.000859f,0.000866f,0.000540f,-0.000000f,-0.000550f,-0.000897f,
-0.000905f,-0.000565f,0.000000f,0.000575f,0.000938f,0.000946f,0.000590f,
0.000000f,-0.000601f,-0.000980f,-0.000989f,-0.000617f,0.000000f,0.000628f,
0.001024f,0.001034f,0.000644f,-0.000000f,-0.000656f,-0.001071f,-0.001080f,
-0.000674f,0.000000f,0.000686f,0.001119f,0.001129f,0.000704f,-0.000000f,
-0.000717f,-0.001170f,-0.001180f,-0.000736f,0.000000f,0.000749f,0.001223f,
0.001234f,0.000769f,-0.000000f,-0.000783f,-0.001279f,-0.001290f,-0.000805f,
0.000000f,0.000819f,0.001337f,0.001349f,0.000842f,0.000000f,-0.000857f,
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0.002421f,0.001513f,-0.000000f,-0.001546f,-0.002530f,-0.002559f,-0.001599f,
-0.000000f,0.001636f,0.002678f,0.002709f,0.001694f,-0.000000f,-0.001734f,
-0.002840f,-0.002874f,-0.001798f,0.000000f,0.001842f,0.003018f,0.003056f,
0.001912f,-0.000000f,-0.001962f,-0.003215f,-0.003257f,-0.002039f,-0.000000f,
0.002094f,0.003434f,0.003481f,0.002181f,-0.000000f,-0.002243f,-0.003681f,
-0.003733f,-0.002341f,0.000000f,0.002411f,0.003959f,0.004019f,0.002522f,
-0.000000f,-0.002601f,-0.004276f,-0.004345f,-0.002729f,-0.000000f,0.002821f,
0.004642f,0.004722f,0.002969f,-0.000000f,-0.003077f,-0.005069f,-0.005163f,
-0.003251f,0.000000f,0.003378f,0.005574f,0.005687f,0.003587f,-0.000000f,
-0.003740f,-0.006182f,-0.006319f,-0.003993f,0.000000f,0.004181f,0.006928f,
0.007098f,0.004497f,-0.000000f,-0.004734f,-0.007867f,-0.008085f,-0.005139f,
0.000000f,0.005448f,0.009087f,0.009377f,0.005985f,-0.000000f,-0.006405f,
-0.010739f,-0.011142f,-0.007154f,0.000000f,0.007757f,0.013102f,0.013703f,
0.008875f,-0.000000f,-0.009817f,-0.016771f,-0.017763f,-0.011668f,0.000000f,
0.013341f,0.023253f,0.025196f,0.016991f,-0.000000f,-0.020774f,-0.037820f,
-0.043229f,-0.031173f,0.000000f,0.046768f,0.100902f,0.151360f,0.187096f,
0.200000f,0.187096f,0.151360f,0.100902f,0.046768f,0.000000f,-0.031173f,
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0.008875f,0.013703f,0.013102f,0.007757f,0.000000f,-0.007154f,-0.011142f,
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0.004642f,0.002821f,-0.000000f,-0.002729f,-0.004345f,-0.004276f,-0.002601f,
-0.000000f,0.002522f,0.004019f,0.003959f,0.002411f,0.000000f,-0.002341f,
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0.002094f,-0.000000f,-0.002039f,-0.003257f,-0.003215f,-0.001962f,-0.000000f,
0.001912f,0.003056f,0.003018f,0.001842f,0.000000f,-0.001798f,-0.002874f,
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0.001946f,0.001191f,0.000000f,-0.001168f,-0.001871f,-0.001853f,-0.001134f,
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0.000983f,0.000000f,-0.000965f,-0.001548f,-0.001533f,-0.000939f,-0.000000f,
0.000922f,0.001478f,0.001464f,0.000897f,0.000000f,-0.000881f,-0.001412f,
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