Patent ID: 6289367
Filing Date: 2001-09-11
Classification: G06F

Abstract:
A digital signal system for determining an approximate logarithm of a value of x having a base b, wherein the approximate logarithm has an integer portion and a decimal portion, comprising:an input for receiving a signal;circuitry for measuring an attribute of the signal, wherein the attribute relates at least in part to the value of x;circuitry for identifying a bounded region within which x falls;wherein the bounded region is one of a plurality of bounded regions;wherein each of the plurality of bounded regions corresponds to a different value of an integer n and is bounded on a lower side by b.sup.n and on a higher side by b.sup.n+1 ; andwherein the identified bounded region identifies the integer portion of the approximate logarithm; andcircuitry for determining the decimal portion of the approximate logarithm by mapping a portion of x to a point along a curve representing an approximation of a portion of an actual logarithm value of x, wherein each point along the curve representing the approximation of the portion of the actual logarithm value of x is the decimal portion of the actual logarithm value of x times a constant.