We present an all-optical adaptive-antenna radio over fiber transport system that uses proven, commercially-available components to effectively deliver standard-compliant optical signaling to adaptive multiantenna arrays for current and emerging radio technology implementations. The system is based on a directly-modulated reflective semiconductor amplifier (R-SOA) and exploits the interplay between transmission-line dispersion and tunable optical filtering to achieve flexible true time delay, with $2\pi$ beam steering at the different antennas. The system was characterized, then successfully tested with two types of signals defined in IEEE 802.16 (WiMAX) standard for wireless networks: a 90 Mbps single-carrier signal (64-QAM at 2.4 GHz) and a 78 Mbps multitone orthogonal frequency-division multiple access (OFDMA) signal. The power budget of this configuration supports a 4-element antenna array.
© 2009 IEEE
Kamau Prince, Marco Presi, Andrea Chiuchiarelli, Isabella Cerutti, Giampiero Contestabile, Idelfonso Tafur Monroy, and Ernesto Ciaramella, "Variable Delay With Directly-Modulated R-SOA and Optical Filters for Adaptive Antenna Radio-Fiber Access," J. Lightwave Technol. 27, 5056-5064 (2009)