Changing the handle properties of a polar plot

I'm trying to change the handle properties to a simple polar plot within Matlab.

At the moment at default the circle is marked every 30 deg, but I want it to increment every 45 deg. I also have a radius of 1 and the graph is segmented through [0 0.2 0.4 0.6 0.8 1] and I want it to be segmented to [0 0.5 1]

I've attached a picture that illustrates how I want my plot to look: