Sec. 6.5] PASSIVE INTERCONNECTION OF AMPLIFIERS 57 



impedance with positive real part, its optimum noise measure Me, opt cannot 

 be less than that of the best amplifier, that is, the amplifier with the least 

 positive eigenvalue of its characteristic-noise matrix. 



Statement 3 of Section 6.4 is an immediate corollary of the previous 

 theorem; that is, 



Passive dissipative imbedding of a given two-terminal- pair amplifier 

 cannot reduce its noise measure to a positive value below Me,opt, provided 

 that the source impedance has a positive real part. 



