Maple can do it, it fruit of years of mathematicians.
The thing is that Maple is done for tremendously Calculus Work and in depth. Matlab, including simulink and toolboxes, many of them DSP and communication oriented toolboxes, is engineering oriented math. It solves things that are pertinent to engineering and solves them by matrices.
You are right, It would be hard for me and you to find a book in DSP to have examples with Maple and it is very possible there isn't a book to suggest DSP with Maple.