s22 for the designed LNA is too less,plz help

hi

i designed a inductively degenerated cascode LNA, the problem is its s22 is too less ( about -0.7db)
plz suggest me some remedy
i am using hspice software
for s parameter calculation , in hspice , the following command is used

.net vout vin rin=50 rout=50
.print s11(db) s21(db) s22(db)

s22(db) is becoming good when i remove the " rout=50 " and if i only use "rin=50"
what is the reason? plz help me

deepak.

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