Thanks for reply! it is from rfmd introduction.let us say :structure=rfic pad(pa output port)+match circuit(need match)+switchplexer and match circuit=microstrip+pads in series The documents introduce firstly connect the pads in series (match circuit) with 0R of match network between PA output pin(IC pad) and switchplexer , and measure the PA output port(IC pad,and not solder RF IC), get the output impedance as ZL(the microstrip+0R+switchplexer ). Then using load pull impedance(vendor supply) as Zopt directly match to ZL. Why not measure the switchplexer input port(not include microstrip+0R of match network) for ZL,and do match ?
Thanks,