Abstract

This paper presents a remote beamforming scheme with fixed wavelength allocation for radio-over-fiber (RoF) systems employing single-mode fiber (SMF). In the proposed scheme, wavelengths with equal narrow spacing are fixedly assigned to each antenna element to equalize the time delay differences between adjacent wavelengths caused by chromatic dispersion. The beam direction of base station (BS) is controlled only by phase control at central station (CS). This offers efficient wavelength utilization and completely remote beam control without information of optical fiber length, and supports systems employing high carrier frequency and long optical fiber. The beamforming performance of the scheme is evaluated theoretically and experimentally. It is shown that the beam pattern depends on optical intensity modulation frequency instead of radiated frequency. Simulations indicate that the required wavelength spacing to obtain a desired beam pattern becomes narrower as more wavelengths are used or intensity modulation frequency becomes higher. Finally, to evaluate the feasibility of the scheme, experiments are conducted under the condition of intensity modulation frequency of 10 GHz, 10 km SMF, and four element array antenna. The results substantially agree with the simulation results, and the main lobe level decrease is within 0.04 dB at wavelength spacing of 50–400 GHz (0.39–3.13 nm on average in C band). The results confirm that the scheme can achieve almost ideal beam patterns and realize beamforming and beamscanning.

System integration and radiation pattern measurements of a phased array antenna employing an integrated photonic beamformer for radio astronomy applications

Maurizio Burla, Chris G. H. Roeloffzen, Leimeng Zhuang, David Marpaung, Muhammad Rezaul Khan, Peter Maat, Klaas Dijkstra, Arne Leinse, Marcel Hoekman, and René Heideman
Appl. Opt. 51(7) 789-802 (2012)

Large-scale true-time-delay remote beamforming with EO frequency combs and multicore fiber

Chenbo Zhang, Peng Lei, Rongwei Liu, Bibo He, Zhangyuan Chen, Xiaopeng Xie, and Weiwei Hu
Opt. Lett. 46(15) 3793-3796 (2021)

Multi-dimensional resources allocation based on reconfigurable radio-wavelength selective switch in cloud radio over fiber networks

Hui Yang, Ao Yu, Xudong Zhao, Qiuyan Yao, Jie Zhang, and Young Lee
Opt. Express 26(26) 34719-34733 (2018)

Scheme for a High-Capacity 60 GHz Radio-Over-Fiber Transmission System

Jing Li, TiGang Ning, Li Pei, and ChunHui Qi
J. Opt. Commun. Netw. 1(4) 324-330 (2009)

An optically controlled phased array antenna based on single sideband polarization modulation

Yamei Zhang, Huan Wu, Dan Zhu, and Shilong Pan
Opt. Express 22(4) 3761-3765 (2014)