CVOR VHF omnidirectional range

the conventional signal encodes station identifier, i(t), optional voice a(t), navigation reference signal in c(t), , isotropic (i.e. omnidirectional) component. reference signal encoded on f3 subcarrier (colour). navigation variable signal encoded mechanically or electrically rotating directional, g(a,t), antenna produce a3 modulation (grey-scale). receivers (paired colour , grey-scale trace) in different directions station paint different alignment of f3 , a3 demodulated signal.

e
(
a
,
t
)


=


cos
⁡
(
2
π

f

c


t
)
(
1
+
c
(
t
)
+
g
(
a
,
t
)
)




c
(
t
)


=



m

i


cos
⁡
(
2
π

f

i


t
)
 
i
(
t
)





+



m

a


 
a
(
t
)





+



m

d


cos
⁡
(
2
π

∫

0


t


(

f

s


+

f

d


cos
⁡
(
2
π

f

n


t
)
)
d
t
)




g
(
a
,
t
)


=



m

n


cos
⁡
(
2
π

f

n


t
−
a
)






{\displaystyle {\begin{array}{rcl}e(a,t)&=&\cos(2\pi f_{c}t)(1+c(t)+g(a,t))\\c(t)&=&m_{i}\cos(2\pi f_{i}t)~i(t)\\&+&m_{a}~a(t)\\&+&m_{d}\cos(2\pi \int _{0}^{t}(f_{s}+f_{d}\cos(2\pi f_{n}t))dt)\\g(a,t)&=&m_{n}\cos(2\pi f_{n}t-a)\\\end{array}}}