From: A monopole broadband circularly polarized antenna with coupled disc and folded microstrip stub lines
W
L
l1
l2
l3
lf
ln
lq
r
24.5
24
6.9
2
2.2
2.05
7.5
11.25
Wf
Wn
Wslot
p
q
m
n
Wstub
g
2.45
1.55
0.1
9.1
11.37
7.2
10.27
0.5
0.2