Patent Document ID: 20020143840
Application ID: 09781951
Patent Flag: 0

Claim One:
1. A method for generating an output signal representing an output value approximating a reciprocal of input value D having a normalized mantissa M (where 1&lE;M<2) represented by an input signal, the input signal comprising a set of N 0 most significant bits and the output signal approximating the reciprocal with a desired precision ∈&equals;2 −N where N&lE;N 0, comprising the steps of: a. for a set of P most significant bits of the input signal, generating a number n of entries in a plurality of lookup tables where n&equals;2 P, including the sub steps of: i. generating a set of input entries y i comprising a set of N significant bits in a, first lookup table, where i&equals;0,..., n−1; and ii. generating a set of input entries K i comprising a set of (N−P) significant bits in a second lookup table, where i&equals;0,..., n−1; b. finding the entries y i and K i in the lookup tables corresponding to the set of P most significant bits of the input signal; c. multiplying K i by a signal comprising a set of (N−P) significant bits following the set of P most significant bits of the input signal; and d. subtracting the set of (N−P) most significant bits from the set of N significant bits of the entry y i.