A Wavelength Division RF-Passive Optical Network for mmWave Analog Radio-over-Fiber Distribution on Large Intelligent Surfaces

Abstract

A grid of optical fibers that utilize analog radio-over-fiber and optical frequency upconversion at the remote radio unit is proposed, to solve the problem of feeding a large distributed antenna array such as large intelligent surfaces with phase coherent mmWave signals in an efficient manner. The 2D-PON grid consists of column fibers which carry LO signals while row fibers carry the modulated IF signals multiplexed over a single fiber. At each intersection, optical power is tapped off and fed into a photodiode where a mmWave RF signal is generated by photonic frequency upconversion of the IF signal using the LO signal. As a proof-of-concept, a 1x2 grid of fibers feeding wavelength division multiplexed data signals and a selector wavelength is demonstrated at 60 GHz with 1 GBaud 16-QAM.