ABSTRACT
In the previous chapter, the z-transform was shown to be an effective tool in linking the time and frequency domains of a discrete-time signal x(n). However, in order to specify practical properties of discrete-time systems, such as low-pass filtering or high-pass filtering, it is necessary to transform the complex z-plane to the real-frequency axis, ω. Specifically, the region of the complex z-plane that is used in this transformation is the unit circle, specified by the region z = ejω. The resulting transform is the Discrete-Time Fourier Transform (DTFT), which will be discussed first in this chapter.
