victoriya
Member level 2
I am designing an lna and mixer for zigbee receiver. my lna gain has varitions between 26.9db for -91dbm input power to 29db for -20dbm!my lna is fixed gain apparently!. but it's gain variations isn't constant.it's gain variations file has been attached here. my lna's output impedance is 772ohm. I think it is ubnormally very high.it's nf is 2.6db ,ip3=3.5dbm and p1db=-25dbm ip3 and p1db difference is very big!!I think it's linearity has problem but i don't know the problem arises from where.other parameters of lna such as s parameters, power and stability is good. my lna's structure is common sorce common gate cascode source inductive degeneration. also I want to know how much power does the active gilbert mixer can receive typically so that it has no distortion ?
thanks.
View attachment lna gain.doc
thanks.
View attachment lna gain.doc