Information Technology Journal1812-56381812-5646Asian Network for Scientific Information10.3923/itj.2012.734.740HuaJingyu GaoZheng KuangWankun XuZhijiang RuanChengfeng 62012116The Weighted Least Squares (WLS) principle is popular in filter design due to its flexibility, where it can output equiripple filters with appropriate target function and weighted function. Therefore, this research studies the influence of the target function in linear phase Finite-Impulse-Response (FIR) filter design by comparing different target functions in WLS iterations. Compared with the traditional one, simulations show that the proposed target function can obtain more accurate stopband start frequencies which will be useful if the stopband start frequency must be precise in applications.]]>3GPP,2008Boyd, S. and L. Vandenberghe,2004Chi, C.Y. and Y.T. Kou,1991Crochiere, R.E. and L.R. Rabiner,1983Konopacki, J. and K. Moscinska,2007Lai, X. and Z. Lin,2010Lai, X.,2009Lim, Y.C., J.H. Lee, C.K. Chen and R.H. Yang,1992Lim, Y.C.,1983Lyons, R.G.,2004McClellan, J.H. and T.W. Parks,2005McClellan, J.H., T.W. Parks and L. Rabiner,1973Proakis, G.J.,2000Rabiner, L.R. and B. Gold,1975Scaglione, A., G.B. Giannakis and S. Barbarossa,1999Vetterli, M.,1986Johnson Jr., A.T.,1990