2-Dimensional beam steering by 2 × 3 photonic antenna using millimeter-wave Radio over Fiber

Abstract

In order to keep up with the explosive mobile traffic increase, many wireless access points in a millimeter-wave band will be deployed in the future. A beam steering of an array antenna is effective for avoiding interference among plural access points, and a 2-dimensional (2-D) array operation is required for more flexible beam control. The Radio over Fiber (RoF) is one of the promising solutions to achieve the array antenna steering by a simple control scheme. In this paper, we demonstrated 2-D beam steering of an array antenna in the millimeter-wave band using the RoF technique. It was experimentally confirmed that a 0.8 nm wavelength change of multiple tunable laser sources yielded a π phase shift of RF signals in the 37 GHz band by utilizing the fiber chromatic dispersion effect over a 1 km-long single-mode fiber propagation, and 2-D beam steering was successfully confirmed. The 2-D antenna steering scheme using a simple photonic approach would be useful for achieving future ultra-broadband and smart antenna systems.

A Tutorial on Optical Feeding of Millimeter-Wave Phased Array Antennas for Communication Applications

“…This becomes especially important as the RF frequency increases since the effect of the dispersion is more notorious. Furthermore, in schemes using optical double sideband modulation, the differential delay induced by chromatic dispersion causes frequency selectivity that may significantly reduce the generated RF power [71,72].…”