Inverted cable design for high-speed, low loss signal transmission
View Patent ↗An improved electrical cable design for high-speed, low loss signal transmission. The improved cable design may be a three-conductor cable having a center conductor, a middle conductor and an outer conductor, where each conductor is separated by a dielectric layer. The electrical cable provides an inverted cable design, in which signal transmission occurs within the middle conductor, the center conductor is used as a return or drain line to ground and the outer conductor is used as a shield. The middle conductor of the electrical cable provides a larger surface area for signal conductance than the center conductor, thereby transmitting signals with significantly less loss (e.g., at least 50% less loss).
1. A method for transmitting a high-speed data signal, the method comprising:
providing an inverted cable, wherein the inverted cable comprises at least:
a center conductor;
a middle conductor concentrically arranged around the center conductor and separated from the center conductor by a first dielectric layer; and
an outer conductor concentrically arranged around the middle conductor and separated from the middle conductor by a second dielectric layer;
coupling the center conductor and the outer conductor to a ground terminal;
coupling the middle conductor to a data terminal; and
transmitting the high-speed data signal along the middle conductor, which has a larger surface area for signal conduction than the center conductor.
2. The method of claim 1 , further comprising coupling the inverted cable between a first printed circuit board (PCB) and a second PCB included within an information handling system (IHS), such that the center conductor and the outer conductor are coupled to ground terminals on the first PCB and the second PCB, and the middle connector is coupled to data terminals on the first PCB and the second PCB.
3. The method of claim 1 , further comprising coupling the inverted cable between a first connector provided on a chassis of a first information handling system (IHS) and a second connector provided on a chassis of a second IHS, such that the center conductor and the outer conductor are connected to ground terminals included within the first connector and the second connector, and the middle connector is connected to data terminals included within the first connector and the second connector.
4. The method of claim 1 , wherein said transmitting the high-speed data signal along the middle conductor comprises transmitting the high-speed data signal at a throughput greater than 15 Gbps.
5. The method of claim 1 , wherein the surface area of the middle conductor is 2 to 5 times larger than a surface area of the center conductor.
6. The method of claim 1 , wherein said transmitting the high-speed data signal along the middle conductor reduces loss through the inverted cable by at least 50% compared to transmitting the high-speed data signal along the center conductor.
7. A system, comprising:
an inverted cable operable for transmitting a high-speed data signal between multiple information handling systems (IHSs), or between multiple printed circuit board (PCBs) included within an IHS;
wherein the inverted cable comprises at least:
a center conductor;
a middle conductor concentrically arranged around the center conductor and separated from the center conductor by a first dielectric layer; and
an outer conductor concentrically arranged around the middle conductor and separated from the middle conductor by a second dielectric layer; and
wherein the inverted cable is coupled for transmitting the high-speed data signal along the middle conductor, which has a larger surface area for signal conduction than the center conductor.
8. The system of claim 7 , further comprising a first IHS and a second IHS, wherein the inverted cable is coupled between a first connector provided on a chassis of the first IHS and a second connector provided on a chassis of a second IHS, such that the center conductor and the outer conductor are connected to ground terminals included within the first connector and the second connector, and the middle connector is connected to data terminals included within the first connector and the second connector.
9. The system of claim 7 , further comprising a first printed circuit board (PCB) and a second PCB included within an IHS, wherein the inverted cable is coupled between the first PCB and the second PCB, such that the center conductor and the outer conductor are coupled to ground terminals on the first PCB and the second PCB, and the middle connector is coupled to data terminals on the first PCB and the second PCB.
10. The system of claim 7 , wherein the inverted cable is operable for transmitting the high-speed data signal in accordance with a Peripheral Component Interconnect Express (PCIe) bus standard, a Serial Attached Small Computer System Interface (SAS) protocol, or a Serial Advanced Technology Attachment (SATA) bus interface.
11. The system of claim 7 , wherein the inverted cable is a dual-axial cable comprising:
a pair of inner cables arranged parallel to one another, wherein each of the inner cables includes a center conductor, a first dielectric layer surrounding the center conductor, and a middle conductor surrounding the first dielectric layer;
one or more second dielectric layers surrounding the pair of inner cables;
an outer conductor surrounding the one or more second dielectric layers; and
a protective outer jacket surrounding the outer conductor.
12. The system of claim 11 , wherein the one or more second dielectric layers comprise a pair of second dielectric layers arranged, such that each of the second dielectric layers surrounds one of the middle conductors included within the pair of inner cables.
13. The system of claim 11 , wherein the one or more second dielectric layers comprise only one second dielectric layer wrapped around the pair of inner cables.
14. The system of claim 13 , further comprising a dielectric spacer inserted between the pair of inner cables.
15. A dual-axial cable terminated at each end with a pair of mating connectors, wherein the dual-axial cable comprises:
a pair of inner cables arranged parallel to one another, wherein each of the inner cables includes a center conductor, a first dielectric layer surrounding the center conductor, and a middle conductor surrounding the first dielectric layer;
one or more second dielectric layers surrounding the pair of inner cables;
an outer conductor surrounding the one or more second dielectric layers; and
a protective outer jacket surrounding the outer conductor;
wherein the center conductors and the outer conductor of the dual-axial cable are coupled to ground terminals on the pair of mating connectors; and
wherein the middle conductors of the dual-axial cable are coupled to data terminals on the pair of mating connectors.
16. The dual-axial cable of claim 15 , wherein the one or more second dielectric layers comprise a pair of second dielectric layers arranged, such that each of the second dielectric layers surrounds one of the middle conductors included within the pair of inner cables.
17. The dual-axial cable of claim 15 , wherein the one or more second dielectric layers comprise only one second dielectric layer wrapped around the pair of inner cables.
18. The dual-axial cable of claim 17 , further comprising a dielectric spacer inserted between the pair of inner cables.
19. The dual-axial cable of claim 15 , wherein the dual-axial cable is operable for transmitting a differential data signal along the middle conductors of the dual-axial cable.
20. The dual-axial cable of claim 19 , wherein the dual-axial cable is operable for transmitting a differential data signal in accordance with a Peripheral Component Interconnect Express (PCIe) bus standard, a Serial Attached Small Computer System Interface (SAS) protocol, or a Serial Advanced Technology Attachment (SATA) bus interface.