GB1255425A - Improvements in the discrete sampling of the values of at least two co-related variables - Google Patents

Abstract

1,255,425. Selective signalling. B. H. KOLSRUD, and C. O. OSTMAN. 28 Oct., 1969, No. 52824/69. Heading G4H. In order to overcome the misleading impression obtained of the way in which a function, Fig. 1, varies, by sampling its value at equally spaced points x 1 , x 2 , a 3 , ... , (since the function may vary widely between successive sampling points) either additional samples can be taken whenever the value of the function crosses preset threshold levels y 1 , y 2 , y 3 , ... , these points being shown by circles in Fig. 2, or sample points can be determined successively, each from the preceding, by using each sample point (X r , Y r ) itself to establish a set of threshold levels X r - #x, x r , x r + #x and y r - #y, y r , y r + #y, as shown in Fig. 3. A block diagram is outlined (Fig. 4, not shown) in which as the function is traced out two series of equiweighted pulses representing x and y displacements are counted, and pairs of counts, representing points on the function, are recorded, e.g. on punched tape, at sampling points determined in accordance with one of the above methods.