2.1.3 1-dB gain compression pointMc cng sut u vo m ti li ca b khuch i tp m thp LNA b suy gim i 1dB c gi l im compression point hay im P1dB. Khi cng sut u vo bt u vt qu ngng ny, li bt u suy gim, ti thi im c th hiu c rng b khuch i khng cn hot ng tuyn tnh na.

Khi , u ra ca tnh hiu y(t) c lin h vi u vo x(t) nh sau (gi nh):

Nu tn hiu u vo l: x(t) = A Cos(t)Khi :

Khi a1 v a3 khc du, tn hiu u ra s b suy gim. Yu cu mc cng tn hiu i vi tn hiu vo nh sau:

2.Third- and second-order intercept points