Metasurfaces for improving co-site isolation for electronic warfare applications
A method for providing control of surface waves propagating on a surface includes forming a surface treatment on the surface, wherein the surface treatment is configured to achieve a tensor surface admittance distribution matrix on the surface determined according to a modified transformation electromagnetics (tEM) equation.
1. A method for providing control of surface waves propagating on a surface, the method comprising:
providing a surface treatment on a portion of the surface; and
configuring the surface treatment to have a tensor surface admittance distribution, wherein the tensor surface admittance distribution is determined according to a modified transformation electromagnetics (tEM) equation
(
Yxx
Yxy
Yyx
Yyy
)
±
=
(
-
(
1
0
0
1
)
k
0
2
-
(
-
Sin
[
ϕ
]
2
Sin
[
ϕ
]
Cos
[
ϕ
]
Sin
[
ϕ
]
Cos
[
ϕ
]
-
Cos
[
ϕ
]
2
)
k
2
)
1
k
0
2
-
k
2
Y
0
2
-
Y
iso
2
2
k
0
Y
0
±
(
(
-
Cos
[
ϕ
+
θ
]
-
Sin
[
ϕ
+
θ
]
-
Sin
[
ϕ
+
θ
]
Cos
[
ϕ
+
θ
]
)
k
0
2
+
(
-
Sin
[
ϕ
]
2
Sin
[
ϕ
]
Cos
[
ϕ
]
Sin
[
ϕ
]
Cos
[
ϕ
]
-
Cos
[
ϕ
]
2
)
k
2
Cos
[
θ
-
ϕ
]
)
1
k
0
2
-
k
2
Cos
[
θ
-
ϕ
]
2
Y
0
2
-
Yiso
2
2
k
0
Y
0
where:
Θ=an angle of power flow
b=Tan [Θ]
k=a tangential wave vector
Φ=an angle of the tangential wave vector
k0=a free space wave number
Y0=an admittance of free space=1/(120*π), and
Yiso=a surface admittance of an untransformed surface; and
wherein providing the surface treatment comprises:
providing a first dielectric on the surface; and
providing a metallic pattern on a first surface of the first dielectric.
2. The method of claim 1 wherein the surface treatment comprises one or more of an isotropic, anisotropic, a homogeneous surface, or an inhomogeneous surface.
3. The method of claim 1 wherein the surface treatment comprises:
an array of unit cells, each unit cell comprising:
a dielectric; and
a metallic pattern on a first surface of the dielectric.
4. The method of claim 3 further comprising a ground plane on a second surface of the dielectric opposite the first surface.
5. The method of claim 4 wherein the at least one unit cell further comprises:
a via between the first surface of the dielectric and the ground plane.
6. The method of claim 4 wherein the at least one unit cell further comprises:
a second dielectric between the ground plane and the first dielectric;
wherein the second dielectric has a second dielectric constant that is different from a first dielectric constant of the first dielectric.
7. The method of claim 3 :
wherein at least one unit cell further comprises at least one tuning element coupled to the metallic pattern, and
wherein the at least one tuning element comprises a resistor, an inductor, a capacitor, a diode, or a voltage controlled varactor.
8. The method of claim 1 wherein the surface treatment further comprises:
a ground plane on a second surface of the dielectric opposite the first surface.
9. The method of claim 8 wherein the surface treatment further comprises:
a via between the first surface of the dielectric and the ground plane.
10. The method of claim 8 wherein the surface treatment further comprises:
a second dielectric between the ground plane and the first dielectric;
wherein the second dielectric has a second dielectric constant that is different from a first dielectric constant of the first dielectric.
11. The method of claim 1 wherein the surface treatment transforms at least one of a polarization, a phase, or a power wavefront of the surface wave.
12. The method of claim 1 wherein the surface treatment comprises a property that reduces the surface wave through dissipative loss.
13. The method of claim 1 wherein the surface treatment radiates energy of the surface wave from a surface of the surface treatment.
14. The method of claim 1 wherein the surface treatment provides co-site isolation between a transmitter and a receiver.
15. The method of claim 1 wherein the surface treatment further comprises:
at least one tuning element coupled to the metallic pattern, and
wherein the at least one tuning element comprises a resistor, an inductor, a capacitor, a diode, or a voltage controlled varactor.
16. A device for providing control of surface waves propagating on a surface comprising:
a surface treatment on a portion of the surface, wherein the surface treatment is configured to have a tensor surface admittance distribution determined according to a modified transformation electromagnetics (tEM) equation
(
Yxx
Yxy
Yyx
Yyy
)
±
=
(
-
(
1
0
0
1
)
k
0
2
-
(
-
Sin
[
ϕ
]
2
Sin
[
ϕ
]
Cos
[
ϕ
]
Sin
[
ϕ
]
Cos
[
ϕ
]
-
Cos
[
ϕ
]
2
)
k
2
)
1
k
0
2
-
k
2
Y
0
2
-
Y
iso
2
2
k
0
Y
0
±
(
(
-
Cos
[
ϕ
+
θ
]
-
Sin
[
ϕ
+
θ
]
-
Sin
[
ϕ
+
θ
]
Cos
[
ϕ
+
θ
]
)
k
0
2
+
(
-
Sin
[
ϕ
]
2
Sin
[
ϕ
]
Cos
[
ϕ
]
Sin
[
ϕ
]
Cos
[
ϕ
]
-
Cos
[
ϕ
]
2
)
k
2
Cos
[
θ
-
ϕ
]
)
1
k
0
2
-
k
2
Cos
[
θ
-
ϕ
]
2
Y
0
2
-
Yiso
2
2
k
0
Y
0
where:
Θ=an angle of power flow
b=Tan [Θ]
k=a tangential wave vector
Φ=an angle of the tangential wave vector
k0=a free space wave number
Y0=an admittance of free space=1/(120*π), and
Yiso=a surface admittance of an untransformed surface; and
wherein the surface treatment comprises:
a first dielectric on the portion of the surface; and
a metallic pattern on a first surface of the first dielectric.
17. The device of claim 16 wherein the surface treatment comprises one or more of an isotropic, anisotropic, a homogeneous surface, or an inhomogeneous surface.
18. The device of claim 16 wherein the surface treatment comprises:
an array of unit cells, each unit cell comprising:
a dielectric; and
a metallic pattern on a first surface of the dielectric.
19. The device of claim 18 further comprising a ground plane on a second surface of the dielectric opposite the first surface.
20. The device of claim 19 wherein the at least one unit cell further comprises:
a via between the first surface of the dielectric and the ground plane.
21. The device of claim 19 wherein the at least one unit cell further comprises:
a second dielectric between the ground plane and the first dielectric;
wherein the second dielectric has a second dielectric constant that is different from a first dielectric constant of the first dielectric.
22. The device of claim 18 :
wherein at least one unit cell further comprises at least one tuning element coupled to the metallic pattern, and
wherein the at least one tuning element comprises a resistor, an inductor, a capacitor, a diode, or a voltage controlled varactor.
23. The device of claim 16 wherein the surface treatment further comprises:
a ground plane on a second surface of the dielectric opposite the first surface.
24. The device of claim 23 wherein the surface treatment further comprises:
a via between the first surface of the dielectric and the ground plane.
25. The device of claim 23 wherein the surface treatment further comprises:
a second dielectric between the ground plane and the first dielectric;
wherein the second dielectric has a second dielectric constant that is different from a first dielectric constant of the first dielectric.
26. The device of claim 16 wherein the surface treatment transforms at least one of a polarization, a phase, or a power wavefront of the surface wave.
27. The device of claim 16 wherein the surface treatment comprises a property that reduces the surface wave through dissipative loss.
28. The device of claim 16 wherein the surface treatment radiates energy of the surface wave from a surface of the surface treatment.
29. The device of claim 16 wherein the surface treatment provides co-site isolation between a transmitter and a receiver.
30. The device of claim 16 wherein the surface treatment further comprises:
at least one tuning element coupled to the metallic pattern, and
wherein the at least one tuning element comprises a resistor, an inductor, a capacitor, a diode, or a voltage controlled varactor.