Question about the definition of Quality factor

[LvW]

I just think that phase slope closely related to Q-factor. You did not convince me that this is not true. ..... Why you so aggressively try to do the opposite even after I sent you a reference to a book that clearly shows that phase slope is closely related to the Q-factor?
RF-OM

Just three questions:
1.) How do you define the Q factor which earlier was called by you "system Q" ?
2.) What means "closely related"? Is there al formula which connects phase slope and the Q factor?
3.) I don´t try to "do the opposite", instead I insist on my view which I think has been proven by simulation. I have sent you some diagrams by e-mail which clearly show that for higher order bandpass systems the phase slope depends on the chosen approximation (even when the bandwidth is the same).

 

[RF-OM]

Okay.
1. I mostly think of the total system Q-factor that is close to f/(delta f) ratio. Why it close but not necessary equal? Because it depends on the system properties itself. In RF books this definition usually considered to be right for components Q-factors >=10. But sometimes we need to use component’s Q-factors instead of the total one. In the book what I refer to you this kind of Q-factors used into formulas for phase slope and Q-factor relation, moreover each element has its own Q (Q1, Q2 and so on).
2. Closely related means close to exact relation that satisfies the accuracy and limitations for the formula that describe the process. Let’s say you use well known Weeler’s formulas to calculate the impedance of microstrip transmission lines. There are two of them and each corresponds to certain ratio of w/h and other limitations. Inside the so called trust intervals each formula considered to describe exact relationship between trace geometry and impedance. The same is true for our case. Any formula almost unavoidable will have its own trust interval, inside of which it considered to be accurate enough for practical usage.
3. I already wrote that I respect your opinion and do not try to push on you. I just have another opinion. I do not try to tell you that you are telling wrong statements. I agree with your theoretical arguments, but I am sure that naked theory is not always the best way to achieve our goal. So far you cannot convince me in opposite. I described to you what I am going to do with this investigation and I am sure that this is right way from engineering and from scientific points of view. I have no doubts that I will find the true and in any case it will beneficial for my ability to do RF design.

I hope these answer will help with our discussion. I just received your e-mail and will check it right now.

Best regards,
RF-OM