Sampling and representation of continuous time signals by direct local integration and spline approximation

The periodic sampling and acquisition of experimental continuous time funct ions by integrating analogue-to-digital conversion is discussed. With speci al regard to intrinsic suppression of disturbances, the theoretical justifi cation of the superiority of this approach over point measurement schemes, and an appropriate mathematical method based on positive spline approximati on operators for the computer internal representation and processing of emp irical functions are established. Then, the hardware design of a correspond ing multichannel interfacing unit, its physical interconnection with comput ers, and the required software support are described. The technique yields considerable complexity and workload reductions, and eases the time constra ints imposed on process control computers. (C) 2001 Elsevier Science Ltd. A ll rights reserved.