SDM and MIMO: An interview with Bell Labs
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Bell Labs is claiming an industry first in demonstrating the recovery in real time of multiple signals sent over spatial-division multiplexed fibre. Gazettabyte spoke to two members of the research team to understand more.
Part 2: The capacity crunch and the role of SDM
The argument for spatial-division multiplexing (SDM) - the sending of optical signals down parallel fibre paths, whether multiple modes, cores or fibres - is the coming ‘capacity crunch’. The information-carrying capacity limit of fibre, for so long described as limitless, is being approached due to the continual yearly high growth in IP traffic. But if there is a looming capacity crunch, why are we not hearing about it from the world’s leading telcos?