A hardware algorithm for computing reciprocal square root

A hardware algorithm for computing the reciprocal square root which appears frequently in multimedia and graphics applications is proposed. The reciprocal square root is computed by iteration of carry-propagation-free additions, shifts, and multiplications by one digit. Different specific versions of the algorithm are possible, depending on the radix, the redundancy factor of the digit set, etc. Each version of the algorithm can be implemented as a sequential (folded) circuit or a combinational (unfolded) circuit, which has a regular array structure suitable for VLSI.