Sampling frequency converter for converting a lower sampling frequency to a higher sampling frequency and a method therefor

A method for converting first time-sequential data Q.sub.i obtained by sampling an analog signal at the rate of a first sampling frequency f.sub.m to second time-sequential data P.sub.j having a second sampling frequency f.sub.n (f.sub.m :f.sub.n =m:n, m<n, m, n:

• integer), comprising the steps of:
• adding (n-m) dummy data to said first time-sequential data Q.sub.i every time m said first time-sequential data Q.sub.i are received to output the same at the rate of said second frequency f.sub.n, and
• receiving said data outputted at the rate of said second sampling frequency f.sub.n and interpolating said received first time-sequential data Q.sub.i based on n kinds of impulse response data obtained by sampling a sampling function for said first sampling frequency f.sub.m at a frequency of the least common multiple of said first and second sampling frequencies f.sub.m and f.sub.n to output the same,
• said interpolating step in said second mentioned step comprising the step of operating a single transversal kind filter having delay elements at the rate of said second sampling frequency f.sub.n,
• the step of operating said transversal kind filter comprising the step of sequentially outputting n kinds of tap coefficient data obtained by inserting (n-m) 0s to said impulse response data in a position corresponding to said dummy data at the rate of said second sampling frequency f.sub.n in a sequential and circulating manner.