To overcome the difficult for higher- order FIR filter to calculate the high -order of inverse matrix, this paper introduces an optimized design of the linear - phase finite - impulse response （FIR） digital filter based on conjugate gradient method. The main idea of this method is the use of the conjugate gradient method to calculate the weighting coefficients of cosine basis functions, and to obtain its unit impulse. So making the global error of the de- signed frequency response of the FIR filter and the frequency response of the ideal filt...
