3Grama L, Rusu C. Phase approximation by divide-and-conquer piece- wise linear fitting of gain. International Symposium on Signals, Cir- cuits and Systems, 2009 : 1——4.
4Gluss B. An ahernative method for continuous line segment curve-fit- ting. Information and Control, 1964 ; 7 (2) :200-206.