For line between Feig module and BNC connector: Coplanar Waweguide Formula from p. 67 in Antennas from Theory to Practice Yi Huang Kevin Boyle J.Wiley ISBN 978-0-470-51028-5 (HB) dimensions in mm er = 4.43; d = 1.5; # board thickness G=0.20; # pcb's Keepaway W=1.5; # pcb's Thickness k= W / (W+2*G); kp = sqrt(1-k*k); ere= ((er+1)/2)*tanh(0.775 * log(d/G) + 1.75) + (k*G/d)*(0.04 - 0.7*k + 0.01 * (1-0.1*er)*(0.25 + k)); Z0 = (30* pi / sqrt(ere)) * (1/pi) * log(2 * (1+sqrt(kp))/(1-sqrt(kp))) W=1.0 Z0 = 57.202 W=1.5 Z0 = 51.587 But then, it don't include effects due to the ground plane my impression is that the ground plane would lessen Z0 /// Vias can be done with dia.0.6mm wire instead of through hole plating.