The requirement for a priori incident field knowledge has been a limiting factor on the practicality of active cloaking. To addresses this issue, an estimation algorithm is presented which allows a cloak to determine and adapt to its electromagnetic environment. Compared to previous iterative techniques, this algorithm possesses a shorter runtime, no convergence issues, and enables measurements to be taken near the target's surface; reducing size and easing implementation of sensing capabilities. Along with presenting the estimation algorithm, a proof-of-concept evaluation is conducted to estimate the incident angle, signal magnitude, and phase offset of a plane wave impinging on a quasi-2D conductive, circular target.