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7th May 2017, 08:03 #21
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Re: implementation of a bandpass filter
I am using that but ... I can't even set my filter order ...
When I choose a lowpass filter I can set the filter order easily but for a bandpass filter, it doesn't work...
so I have 2 problems now!
1 I can't set filter order using Filter Design Guide (N=5, er,banspass)
2 then attenuation
   Updated   
sure, an equal ripple bandpass with a center frequency of 3.5GH and FBW=20%...for 5dB, N=5

7th May 2017, 14:54 #22
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Re: implementation of a bandpass filter
Filter's order gives the attenuation.
sure, an equal ripple bandpass with a center frequency of 3.5GH and FBW=20%...for 5dB, N=5
Ap=5 dB
As= 122 dB
Fs1=0.28 GHz
Fp1=2.8 GHz
Fp2=4.2 GHz
Fs2=42 GHz
That gives a 5th order Band Pass filter.
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7th May 2017, 14:54

13th May 2017, 10:14 #23
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13th May 2017, 10:14

13th May 2017, 13:02 #24
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13th May 2017, 13:11 #25
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13th May 2017, 13:11

13th May 2017, 14:09 #26
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Re: implementation of a bandpass filter
5 dB ripple is quite high, that's true. It involves particularly a high Q of individual LC sections and respective sensitivity against parameter variations, also possibly extreme L and C values.
I don't know if it's an exercise or a real hardware design problem.
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19th May 2017, 13:34 #27
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Re: implementation of a bandpass filter

19th May 2017, 15:03 #28
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Re: implementation of a bandpass filter
I got similar values as ADS with Nuhertz Filter Solutions. How did you calculate the filter? Same topology, same parameters?
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19th May 2017, 15:03

19th May 2017, 16:54 #29
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Re: implementation of a bandpass filter
It is very difficult to implement a 5th order band pass filter with only 1 pair of capacitor and inductor..
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19th May 2017, 18:16 #30
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Re: implementation of a bandpass filter
I see C1 = 0.1066 pF , L1= 19.3919 nH if you design the filter for 0.5 dB pass band ripple.
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22nd May 2017, 16:01 #31
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Re: implementation of a bandpass filter
I guess I had some mistakes in the manual calculation ...thanks all
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