from math import sqrt
from __future__ import division
fr=10 #GHz(center frequency)
fr=fr*10**9 #Hz(center frequency)
epsilon_r=10.2 #(constant)
h=0.127 #cm(height of sustrate)
c=3*10**10 #cm/s(Speed of light)
W=c/2/fr*sqrt(2/(epsilon_r+1)) #cm(Physical dimension)
epsilon_reff=(epsilon_r+1)/2+(epsilon_r-1)/2*(1+12*h/W)**(-1/2) #(effective constant)
delta_L=h*0.412*(epsilon_reff+0.3)*(W/h+0.264)/((epsilon_reff-0.258)*(W/h+0.8)) #cm(distance)
L=c/2/fr/sqrt(epsilon_reff)-2*delta_L #cm(distance)
print "Design values of W & L are : %0.3f & %0.4f cm "%(W,L)