All physical channels are band-limited, such that,
X(f) = 0 for |f| > W
A Gaussian Channel is limited in both power and bandwidth. For this reason we encounter phrases, such as, "A band-limited Gaussian Channel" (for e.g., in the opening statement of Channel Capacity theorem).
I have two questions:
- Why/How a Gaussian Channel is band-limited and Power limited?
- What are physical implications of using such a channel?
Please help/guide me to understand this.