Conceptual Question from Signal Processing - Impulse Response and AR Coefficients
Impulse Response is basically the FIR coefficients of the system.
Namely, a system $ H $ with an impulse response given by $ f [n] $ and a Filter $ F $ with an FIR representation of $ {f[0], f[1], \cdots, f[n]} $ are equivalent.  

Now, systems with Feedback are equivalent of both FIR and IIR (AR) filters.
But given infinite length of FIR model any LTI system can be represented by FIR coefficients.  

The relation could be easily displayed by the Laplace Transform of the system.