determinant of transfer function

[bhuvanesh]

i am studying control system i crossed this transfer function

H(jw)=(1-jw/1+jw)

now taking determinant of this

|H(jw)|=1

My question in what way the determinant is usefull to learn about the systrem.Here the determinant of transfer function is 1,so the 1 saying anything about the system

 

[LvW]

|H(jw)|=1 and phi(jw)=-2arctan(w).
It is an alppass with a phase between 0 and -Pi.

 

[bhuvanesh]

sir,This is what i really need but i am not clear yet

|H(jw)|=1 .so does it mean that high pass ?

does phi(jw) mean phase of transfer function ?

how do you say its all pass with phase between 0 to -pi?

 

[LvW]

N0 - it`s not a highpass;
Yes - phi(jw) is the phase function;
The name is "allpass" because this filter lets pass all frequencies with the same amplitude, only the phase goes from zero to -Pi (continuously).

 

[bhuvanesh]

if suppose the determinant gives decreasing amplitude value for giving increasing frequency value .is that low pass?
if suppose the determinant gives increasing amplitude value for giving increasing frequency value .is that high pass?