and 
 , design an 
 ladder network of n sections such that the terminated transfer voltage ratio 
 is maximized at a given phase shift 
 . This problem is solved explicitly. It was found that the optimum 
 phase-shift network is a geometrical progression network-properly terminated at both ends. In the distributed case ( 
 approaches infinity), the optimum 
 network is an exponentially tapered line, terminated by four lumped impedances.