# How to compose a Discrete Prolate Spheroid (DPSS) dictionary?

I have a model of signal as $$Y=AX + N$$ where $$Y$$ is received data in a linear array, $$A$$ is steering matrix, $$X$$ is data of sources and $$N$$ is noise. If $$A$$ has the form of $$A=\exp(\alpha \sin(\theta))$$ where $$\alpha$$ can be consider as a constant, $$\theta =[0,180]$$. How can I compose a dictionary of $$A$$ based on DPSS-to solve an estimation problem?