Bidirectional 60 GHz RoF system with two millimeter-wave signals generated by a novel generation scheme

A two millimeter-wave signal generation scheme for a bidirectional 60 GHz radio-over-fiber system is theoretically analyzed and numerically verified. Three dual-electrical Mach-Zehnder modulators (MZMs) and two optical inter-leavers (OILs) are employed, and MZM1, MZM2, and MZM3 are biased at the minimum, maximum, and minimum transmission points, respectively. The two OILs and a fiber Bragg grating are used to separate the subcarriers after transmission. In the scheme, a tunable laser serves as the optical source, and two 60 GHz millimeter-wave signals with modulating data are generated to transmit diversity, and a remote local oscillator is also generated. The analytical models for transmission through a dispersive medium are confirmed by simulations. It is found that chromatic dispersion has little impact on the bit error rate performance when a narrow-linewidth laser and a noise management technique are employed.