Best flatband response

From Figure 6.27 it can be seen that the peak modulus Mp is 4dB, occurring at ujp = 1.63rad/s. The bandwidth is 2.2rad/s. For the best flatband response, the open-loop frequency response locus should follow the 0 dB M contour for as wide... 

Fig. 6.28 Nichols chart showing best flatband response (curve (a)) and response with /Wp=3dB (curve (b)).

Figure 6.29 (see also Appendix 1, fig629.m) shows the closed-loop modulus frequency response. Curve (a) is the best flatband response, curve (b) is the response with Mp set to 3dB. 

Running script file fig629.m will produce the closed-loop frequency response gain diagrams shown in Figure 6.29 for Example 6.4 when K = 3.8 and 3.2 (value of K for best flatband response). 

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