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BELL SYSTEM TECHNICAL JOURNAL 



wc(f) 



LOW FREQUENCY OUTPUT OF L I NEAR RECTIFIER 

 APPROXIMATION -SECOND ORDER PRODUCTS ONLY 



INPUT- V= Pcos zrrfpt + noise 

 jo V < I 



ouTPUT = i= j^; y>oj» 



OUTPUT D.C.= P*'„+ P Wg h(,2 



ik. vvn 



Kf. ^ = '-.='' &) 



P/2 P 



FREQUENCY 



Fig. 9 



INPUT SPECTRUM 



INPUT NOISE 



T""i 



x = 



1.5 2.0 2 5 



Ave SINE WAVE POWER P^ 



AVE NOISE POWER 2 P Wq 



Fig. 10 — Coefficients for linear detector output shown on llg. 9 

 P//02 = ^/- iFiG; 1; -.v) //n = \\ / - iFi(h 2; -x) 



We make the first comparison between (4.10-15) and (4.10-16) by letting 

 Q ^ oc . It is seen that both reduce to 



Wcif) = \ [wif, - /) + w{f, + /)] (4.10-19) 



