This paper presents a self-adjustment of the length of the channel impulse response using a classical Cholesky Factorization. This is of special importance in the context of algorithms containing a matrix inversion and the rank of this matrix is strongly related to the length of the channel impulse, i.e. interferer cancellation algorithm. When the length of the channel impulse response is overestimated, the matrix inversion is carried out with a singular matrix. A self-adjustment is then required to avoid an increase in the noise level.