An accurate FIR approximation of ideal fractional delay in Hilbert space

This paper presents an improved low order technique for the design of FIR fractional delay (FD) filters. This method is based on a new use of the least square method in Hilbert space to approximate the ideal FD transfer function with a FIR filter. The main advantages of the resulting filter are: very good response at all frequencies and a good method to create very small delay. Design examples are demonstrated to illustrate the effectiveness of this new design approach.