This letter presents a novel modulation approach for simultaneous generation and transmission of optical radio-frequency (RF) wireless vector signal and baseband (BB) wireline signal using a single-electrode Mach-Zehnder modulator. Based on a double sideband with carrier suppression scheme and properly predistorted driving vector signal, a 2.5-Gb/s quadrature phase-shift keying (QPSK) signal at 60 GHz is generated with a 1.25-Gb/s BB ON-OFF-keying (OOK) signal. The proposed system can carry higher spectral efficiency vector signals and needs no optical filter to separate the BB and RF signals at remote nodes. Moreover, optical RF signal generation with frequency doubling is also achieved to reduce the bandwidth requirement of the transmitter. After transmission over 25-km single-mode fiber, the power penalties of the generated QPSK and OOK signals are about 4 and 0.1 dB, respectively.
- Mach-Zehnder modulator (MZM)
- optical frequency multiplication
- optical millimeter-wave
- radio-over-fiber (RoF)
- wavelength-division multiplexer (WDM)