JPS6455788A - Data interpolating device for digital signal - Google Patents

Abstract

PURPOSE:To obtain an interpolation value close to a true value even when erroneous data are continuous by obtaining a primary difference due to the difference between present data and preceding data, and a secondary difference due to the difference between a present primary difference and a preceding primary difference and operating them. CONSTITUTION:By subtracting the previous data with a delaying device DL1 from the present data inputted to the delaying device DL1 by a subtracter SB1, data A10 of a primary difference are outputted from a difference device A1. By subtracting the data of the previous primary difference obtained by a delaying device DL2 from the present primary difference data with a subtracter SB2, the data A20 of the secondary difference are outputted. First, the time string controlled by a timing generating device 4 is inputted from an error correcting circuit 2 to an interpolating device 1. At such a time, when the error of the data cannot be corrected by the circuit 2, switches S1-S3 are switched to a contact (b) side, and the output of an adder AD2 is transferred to a D/A converter 3 as an interpolation value. By the constitution, even when the erroneous data are continuous, the interpolation value close to the inherent value can be obtained.