MIPG algorithm stability improvement for adaptive IIR notch filter

A modification of error function of a modified indirect plain gradient algorithm (MIPG) is presented in this paper. The objective is to improve the stability of the MIPG. In this modification, we have derived a new adaptive algorithm, namely, improved MIPG algorithm (IMIPG). The methodology of modifying is the sum of the two error functions. The former is of the MIPG algorithm and later is of the plain gradient (PG) algorithm. The IMIPG algorithm not only has fast convergence speed but it also provides high stability, especially when the signal frequency is close to 0 or π.