Horn antenna and Wireless LAN

How to adjust so high reactive impedance (50+j60) of horn antenna because I'm not sure that I can adjust output(input)impedance of Wireless LAN card?
What is exactly output impedace of this card, is it exactly 50R of real part and 0R of imag. or some else ?
I'm comfused because when I was buid output amplifier I had output capacitor to adjust this, but now

measure the output return loss of the lan card. if it is complex conjugate of the horn input impedance, that'll will be perfect. else
use a capacitor in series will match both impedance