Efficient block LS design of FIR filters with linear phase

This paper is concerned with the efficient determination of FIR least squares filters with linear phase. The general unknown statistics case is considered, whereby only sample records of the input and the desired response signals are available. Both linear phase cases with phase delay and group delay are examined. Taking advantage of the underlying near-to-Toeplitz structure of the resulting normal equations, a fast algorithm is developed that recursively produces all linear phase filters orders for a single block of data.