What do you mean by microstrip response?

I assume you want the very low resistivity of graphene.

I don't think grapheme has been used over large enough areas to make a microstrip line with it more than a mm long.  You may be able to lay down a number of individual graphene flakes a millimetre across on Rogers material to make a microstrip, by lifting flakes off graphite using sticky tape.

That would be more industrious than industrial, Malcolm, would it not?

I think it might be very difficult to do, but might demonstrate low loss and increase the incentive to develop industrial methods to generate grapheme films of useful size, if more incentive is needed.

Thanks dear Malcome White and Denis Jaison

Exactly I mean small pieces of graphene