ku band lna design help?

i want to deign a lna operated for 17~18GHz using mic technique(two stage).
design goal:nf<1.8dB,gain>18dB,vswr(out)<2
please give me some hemt(not hemt chip).
and what should i noitce for such hign frequency design.
(i've designed many lnas for upper x band)
give me some advice and papers or design examples please.
thank you for all.