MAMSK-OFDM Signal for RoF Access With Increased Tolerance Toward Frequency Offset

A novel multi-amplitude minimum shift keying (MAMSK) orthogonal frequency division multiplexing (OFDM) signal is proposed for 60-GHz radio-over-fiber (RoF) access system. It can increase the tolerance toward frequency offset of an OFDM signal due to the faster roll-off side-lobe. In the experiment, a 3.21-Gb/s 2AMSK-OFDM signal is transmitted over 22 km single mode fiber (SMF) and 5 m air link successfully. Compared with a conventional 8QAM-OFDM signal, the signal-to-interference ratio (SIR) of 2AMSK-OFDM is improved by 11.5 dB at a frequency offset of 0.15. The performance is improved by 1.7 dB under a normalized frequency offset (FO) of 0.2.