A new frequency response plot of linear SISO systems

The projection of the Nyquist Diagram of an SISO linear systems onto the Riemann sphere is recently used to represent the frequency responses. However, it is difficult to display the Riemann plot clearly in a plane since the Riemann sphere is a three dimensional object. To address this problem, the map projection of Riemann plot is introduced to obtain a two dimensional plot. The new frequency response plot plays the same role in modern robust control as Riemann plot, and easy to draw in a plane.