Systems and methods for exciting long slot radiators of an RF antenna
Provided is a radiator transition assembly for exciting a long slot radiator of an antenna, the transition assembly including a folded flexible circuit substrate including at least two folds forming a long slot radiator, an excitation circuitry configured to generate signals for exciting the long slot radiator, and a microstrip transmission line coupled to the excitation circuitry and positioned along the folded flexible circuit substrate, where the microstrip transmission line extends across an opening of the long slot radiator.
1. A radiator transition assembly for exciting a long slot radiator of an antenna, the transition assembly comprising:
a folded flexible circuit substrate comprising at least two folds forming a long slot radiator;
an excitation circuitry configured to generate signals for exciting the long slot radiator; and
a microstrip transmission line coupled to the excitation circuitry and positioned along the folded flexible circuit substrate, wherein the microstrip transmission line extends across an opening of the long slot radiator, wherein the opening is defined by a space between adjacent folds of the folded flexible circuit substrate;
a flat flexible circuit substrate attached to the folded flexible circuit substrate;
a coupling strip positioned on a to surface of the flat flexible circuit substrate and extending across the opening;
a via coupling a first end of the coupling strip to the microstrip transmission line; a ground plane positioned on a to surface of the folded flexible circuit substrate, wherein the microstrip transmission line is positioned on a bottom surface of the folded flexible circuit substrate; and
a second via coupling the ground plane to a second end of the coupling strip, wherein second end of the coupling strip is opposite to the first end of the coupling strip.
2. The radiator transition assembly of claim 1 , wherein the flat flexible circuit substrate is attached to the folded flexible circuit substrate using one or more non-conductive adhesive strips.
3. The radiator transition assembly of claim 1 , wherein the opening comprises a slot aperture in the folded flexible circuit substrate.
4. The radiator transition assembly of claim 3 , wherein the opening comprises a elongated rectangular shape.
5. The radiator transition assembly of claim 4 , wherein the opening further comprises two transverse stubs, each having an end joining one of the ends of the elongated rectangular shape.
6. The radiator transition assembly of claim 3 , further comprising a flat flexible circuit substrate attached to the folded flexible circuit substrate at a first end of the folded flexible circuit substrate;
wherein the slot aperture is positioned proximate to a second end of the long slot radiator opposite to the first end.
7. The radiator transition assembly of claim 1 , further comprising:
at least one tuning strip positioned to partially cover the long slot radiator, wherein the at least one tuning strip comprises a conductive material.
8. The radiator transition assembly of claim 7 , wherein the at least one tuning strip is positioned on a top surface of the flat flexible circuit substrate.
9. The radiator transition assembly of claim 7 , further comprising a second flat flexible circuit substrate attached to the flat flexible circuit substrate,
wherein the at least one tuning strip is positioned on a surface of the second flat flexible circuit substrate.
10. The radiator transition assembly of claim 1 , wherein the microstrip transmission line comprises copper.
11. The radiator transition assembly of claim 1 , wherein the folded flexible circuit substrate comprises a liquid crystal polymer material.
12. The radiator transition assembly of claim 1 , wherein the excitation circuitry comprises a transmit/receive chip circuitry configured to generate signals for exciting a radiator of an antenna.
13. The radiator transition assembly of claim 1 ,
wherein the microstrip transmission line extends along a bottom surface of the folded flexible circuit substrate, transitions to a top surface of the flat flexible circuit substrate, and extends across the opening.
14. The radiator transition assembly of claim 1 :
wherein the via is positioned within a first clearance hole in the flat flexible circuit substrate, and
wherein the second via is positioned within a second clearance hole in the flat flexible circuit substrate.
15. The radiator transition assembly of claim 1 , wherein the coupling strip comprises two coupling legs, each extending across the opening.
16. The radiator transition assembly of claim 15 , further comprising:
a ground plane positioned on a top surface of the folded flexible circuit substrate, wherein the microstrip transmission line is positioned on a bottom surface of the folded flexible circuit substrate;
a second via coupling the ground plane to an end of a first coupling leg of the coupling strip; and
a third via coupling the ground plane to an end of a second coupling leg of the coupling strip.
17. The radiator transition assembly of claim 1 , further comprising:
at least one tuning strip positioned on a top surface of the flat flexible circuit substrate to partially cover the long slot radiator, the at least one tuning strip comprising a conductive material.