Chinese Optics Letters, 2018, 16 (4): 040603, Published Online: Jul. 12, 2018
50 GHz optical true time delay beamforming in hybrid optical/mm-wave access networks with multi-core optical fiber distribution
Abstract
We propose and experimentally validate an optical true time delay beamforming scheme with straightforward integration into hybrid optical/millimeter (mm)-wave access networks. In the proposed approach, the most complex functions, including the beamforming network, are implemented in a central office, reducing the complexity and cost of remote antenna units. Different cores in a multi-core fiber are used to distribute the modulated signals to high-speed photodetectors acting as heterodyne mixers. The mm-wave carrier frequency is fixed to 50 GHz (V-Band), thereby imposing a progressive delay between antenna elements of a few picoseconds. That true time delay is achieved with an accuracy lower than 1 ps and low phase noise.
Álvaro Morales, Idelfonso Tafur Monroy, Fredrik Nordwall, Tommi Sørensen. 50 GHz optical true time delay beamforming in hybrid optical/mm-wave access networks with multi-core optical fiber distribution[J]. Chinese Optics Letters, 2018, 16(4): 040603.