Apparatus and method for evenly distributing events over a periodic phenomenon

摘要

In a system for reducing artifacts in a desired image due to substantially periodic variations in the imaging signal detected from a portion of an object under examination, a method and apparatus for generating from a signal y(t) related to the variations and whose values are not equally likely, a signal phi (t) whose values are substantially equally likely for use in distributing events substantially evenly over the variations. In order to provide the signal phi (t), an apparatus is disclosed for executing the following steps: (a) establishing a historical data base derived from values of the signal y(t) for a period of time preceding the present time, (b) measuring parameters related to the present value of the signal y(t); and (c) producing a value for phi (t) using the present measured parameters and the historical data base; wherein the values of phi (t) are more evenly distributed than the values of y(t).