Researchers are working on a cabling system that could provide data transfer speeds several times faster than existing USB connections using an extremely thin polymer cable, in a system that echoes the design path of Thunderbolt.
Presented at the IEEE International Solid State Circuit Conference in February, the research aims to develop a type of connection that provides much better connectivity than current methods. In part, it aims to achieve this by replacing copper wiring with something else.
Copper is typically used for wires such as USB and HDMI to handle data transfers, but requires a lot of power to operate for high levels of data transmission. “There is a fundamental trade-off between the amount of energy burned and the rate of information exchanged,” said MIT graduates and lead author Jack Holloway.
While “increasingly bulky and expensive” copper could be replaced by fiber optic cables, it is introducing its own problems. Because silicon chips have difficulty treating photons, this makes the interconnection between cable and computers more difficult to optimize.
According to Holloway, “there are all kinds of expensive and complex integration schemes, but from an economic point of view, it is not an excellent solution”, which led the developers to create their own version.
Combining the benefits of copper and fiber optic pipes, a plastic polymer is used by researchers. This makes it cheaper to manufacture than copper wires, which could be an attractive proposition for cable manufacturers.
The polymer can also use subterhertz electromagnetic signals, which are more energy efficient than copper at high data loads. It is believed that this efficiency is close to that of fiber optic systems, but essentially with better compatibility with silicon chips.
Low-cost chips are associated with the polymer pipe that can generate high-frequency signals strong enough to transmit them directly into the pipe. As such, the system is expected to be manufactured using standard methods, which also makes production profitable.
The cables themselves can also be extremely thin, with the cross-section of the interconnection measuring 0.4 millimeters by a quarter of a millimeter, smaller than typical copper variants.
This small, hair-like cable can be used to carry data over three different parallel channels, allowing it to achieve a total bandwidth of 105 gigabits per second. Joining the pipes together could bring the cables in the terabit-per-second range, while remaining reasonably priced.
Echoes of lightning
The system, using chips at each end of a cable, uses a relatively similar concept to Thunderbolt cables, although with a different conduit in use. In each case, the chips inside the cable are used to handle the data that is inserted into the cable at one end and the other, while treating the interface with the pipe itself.
It seems plausible that such a system could be used for a future Thunderbolt-style connection, allowing it to far exceed the current upper limit of 40 Gbps.
Another connection with Thunderbolt is research funding. While Thunderbolt was developed by Intel and Apple, research on unnamed polymers was also funded by Intel, along with Raytheon, the Naval Research Laboratory and the Naval Research Bureau.