Digital Integrator Design Using Recursive Romberg Integration Rule and Fractional Sample Delay

In this paper, the digital IIR integrator design based on recursive Romberg integration rule and fractional sample delay was investigated. Starting with the trapezoidal integrators, the approximation error of frequency response of digital integrator can be reduced recursively by using Romberg rule. Although the proposed IIR digital integrators involves the implementation of fractional sample delays, this problem is easily solved by applying well-documented design techniques of the FIR Lagrange and IIR all-pass fractional delay filters. Several design examples are illustrated to demonstrate the effectiveness of the proposed method.