Live From SMPTE: Belden Talks 12-GHz Coax for 4K Needs
Coax will still play a role in the world of 4K and 12 GHz, according to Steve Lampen, multimedia technology manager for Belden, who laid out plans for a 12-GHz single-link coaxial cable that the company plans to introduce in first quarter 2015.
“Single-link 12-GHz requires new design,”he explained, speaking at this week’s SMPTE Conference in Hollywood. One of the big changes will be doubling the Nyquist rate in order to give users longer distances to play with. The current 1694A cable, for example, will be able to reach distances of 69 meters and still be able to send a high-quality signal.
“Is 69 meters far enough? Time will tell,” he said.
The cable will also be thicker and include a tri-shield, giving it a -20-dB improvement over foil/braid at high frequencies.
“By bonding the foil to the core, we will improve return loss and ruggedness, as, at 12 GHz, there are super-tiny wavelengths, and even subtle changes in the difference in distance between the foil and core can have huge effects on the signal,” explained Lampen. “So, by bonding the foil to the core, that distance will not change even when the cable is bent.”
The cable will be introduced early next year, and Lampen said it will allow those who are comfortable working with coax to not have to move to fiber in order to embrace 4K. The only remaining uncertainty is when the connectors will become available, because the 4K signals will require improved connectors. Using existing connectors, he said, would be like using wooden wheels on a sports car and going 500 miles per hour.