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Microwave High Pass Filter Phase Shifting

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monolothics

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Hi, all

I have a problem here,,
How can i design a High Pass Filter with given phase shift??

Thank you
 

When the input frequency is above the filter's pole frequency, phase leads.

When it is below the pole frequency, phase lags.

To obtain a particular phase shift will involve drawing parallelogram shapes, with resistance being one axis, and reactance being the other axis.

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The phase shifts can be accentuated by using higher order filters.

As shown in graphs in the article below.

Phase Response in Active Filters -- Part 2, the Low-Pass and High-Pass Response

http://www.analog.com/library/analogDialogue/archives/43-09/active_filters.html
 

Thanks for the reply,,
but i still can't get with this picture LPF_response.jpgLPF1.jpg

How can the phase response is like that, unlike the phase response at the article above???

the filter specification on the picture is :
the operation frequency is 5150 MHz - 5875 MHz
cut-off frequency is 1 GHz
Bandwidth is 800 MHz
 

Hi, all
I have a problem here,,
How can i design a High Pass Filter with given phase shift??
Thank you

Please reformulate your question. To me it is not clear what you really want to know.

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When the input frequency is above the filter's pole frequency, phase leads.
When it is below the pole frequency, phase lags.

Phase lags?

First order highpass: Phase goes from +90 to zero deg
Second order: Phase goes from +180 to zero deg.
 

Phase lags?

First order highpass: Phase goes from +90 to zero deg
Second order: Phase goes from +180 to zero deg.

Thank you, you are correct. I should have listened to my inner critic saying I was reckless and my statement needed further defining.

A capacitor alone, or a coil alone, can only shift phase within a range of 90 degrees. (First order.)

I had spent time watching a second order filter (two capacitors, or coil and capacitor). I watched how it shifts a sinewave before and after the 90 degree mark. (A recent thread was asking about a filter that leads 90 degrees.)

I watched sinewaves going across the screen. I watched lissajous figures changing shape.

I developed tunnel vision from fixating on the 90 degree figure. It caused me to think of the phase shift as leading and lagging, whereas it was only phase leading, in the range you stated.

A third order filter goes yet a further step more.
 

Please reformulate your question. To me it is not clear what you really want to know.

What i wanto to know is, how can i design a HPF or LPF with an output of certain phase shift???
for example, i want a HPF that can give a 22,5 degree phase shift, how can i do that??
 

What i wanto to know is, how can i design a HPF or LPF with an output of certain phase shift???
for example, i want a HPF that can give a 22,5 degree phase shift, how can i do that??

What means "certain phase shift"? A certain value at one single frequency or a certain phase function?

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........ It caused me to think of the phase shift as leading and lagging, whereas it was only phase leading, in the range you stated.

On the other hand - one could ask, however: What means "90 deg phase lead"? Isn`t it more correct to speak about "270 deg phase lag"? Perhaps a question of "cause and effect"?
 


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