Post a photo or a sketch of what you want the chart to look like. It's entirely possible in AE using a number of techniques but it won't be in real time. You would use expressions to measure the distance between two null objects - easy with the Length method that is part of the expression language library that comes with AE. You can turn that into a motion path or scale or angle or any value you can animate. Without details and a sketch of what you want the final product to look like there are too many op;tons to give you what you want as a list of steps.
You will need to be fairly familiar with AE to pull this off. If you have never worked with expressions before you'll either need to have someone translate your vision into reality or spend a few days experimenting on your own.
Sure you can produce a polar chart in AE, you just completely lack any experience in using the program, which will make this endlessly complicated for you.
In this case, it represents a 30-second clip where the y-value is the distance between the two null objects each second. The data is just an example but as you mentioned, it could be obtained from the length method using expressions. Getting that data isn't the difficult part. Using it to construct a similar/better polar chart animation in AE would be, as pointed out by you and Mylenium, a steep hill to climb.