We address the problem of minimum mean-squared error (MMSE) estimation where the estimator is constrained to belong to a prede ned set of functions. We derive a simple closed form formula that reveals the structure of the restricted estimator for a wide class of constraints. Using this formula we study various types of constrained estimation problems that arise commonly in the elds of signal processing and communication.
Tomer Michaeli, Yonina C. Eldar