Z transform maps a function of discrete time n to a function of z On a higher level, the z transform, viewed as a linear operator, maps an entire signal x. Although motivated by system functions, we can define a z trans form for any signal.
Z - Transforms and its Properties
It applies equally well to describing systems as well as signals using.
H(z) provides a new way of thinking about the frequency response
Not an ideal lpf or hpf or bpf, but instead, something with particular zeros in the frequency domain. The z transform of x, on the other hand, x (z), maps every complex number z ∈ c to a new complex number x (z) ∈ c
