In this paper, we propose a reverse modulation fiber-wireless system with two jointed DSP algorithms. The signal in the system is OFDM modulated millimeter wave (mm-wave) at 60GHz. In order to improve transmission of this system, the discrete Fourier transform spread (DFT-Spread) technology and the averaging of the channel frequency response (H-averaging) technology are applied. The DFT-Spread technology helps to reduce the peak-to-average power ratio (PAPR) of the OFDM signal, and the H-averaging technology helps to optimize channel estimation. This is the first time that the two kinds of technology were used together in this reverse modulation system. According to the simulation, the 22Gbit/s 16QAM-OFDM at 60GHz can be generated and transmitted for 90km fiber transmission under the soft decision forward error correction (SD-FEC) threshold 3.8×10-3. The results show that the two jointed DSP algorithms can improve the reverse modulation system transmission performance obviously.
In order to reduce the number of devices in and cost of a multifrequency vector millimeter-wave (mm-wave) signal generation system, we propose a novel scheme for multifrequency vector mm-wave signal generation based on one dual-arm Mach-Zehnder modulator (MZM) without optical filtering. This scheme utilizes the carrier suppression modulation of a single modulator, without the need for optical filtering and combines precoding technology to generate high-frequency QPSK and 16 QAM mm-wave signals. The transmitter is applied with precoding technology to make the frequency multiplying vector mm-wave signal display regular vector modulation at the receiver, and the system is optimized with a phase factor to ensure that the phase distribution of QPSK signal at the receiver is symmetrical. We demonstrated the generation of 4-Gbaud 76 GHz QPSK and 16 QAM vector mm-wave signals through simulation. The simulation results show that, at a fiber transmission distance of 12 km, when the launched optical power of the PD is greater than −20.535 dBm, the bit error ratio (BER) of the QPSK signal is lower than the hard-decision forward error correction (HD-FEC) threshold of 3.8 × 10−3. At a fiber transmission distance of 10 km, when the launched optical power of the PD is greater than −18.637 dBm, the BER of 16 QAM signal is also lower than 3.8 × 10−3.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.