Optical Carrier transmission rates

About: Optical Carrier transmission rates is a research topic. Over the lifetime, 2463 publications have been published within this topic receiving 33293 citations.

Bidirectional long-reach PON using Kramers-Kronig-based receiver for Rayleigh Backscattering noise and SSBI interference elimination

Abstract: In this paper, a novel bidirectional long-reach PON is proposed and demonstrated by using Kramers-Kronig (KK)-based receiver and 7-core fiber to simultaneously cope with the induced signal-signal beating interference (SSBI) and Rayleigh backscattering (RB) noises. A low-cost self-homodyne detection using only one PD is used at both OLT and ONU, and the middle core of 7-core fiber is used to deliver the seed light to ONUs for colorless upstream transmission, and the upstream and downstream signals are transmitted simultaneously over the same outer core for each ONU. By this means, the signals and local oscillators for upstream and downstream transmission all originate from the same laser which is located at OLT. With the help of the KK-based receiver, SSBI could be effectively eliminated and the fiber dispersion can also be digitally compensated due to the reconstruction of the complex field of the received signal. Moreover, by using single sideband Nyquist-shaped subcarrier modulation with 16-ary quadrature amplitude modulation (SSB-Nyquist-16QAM) technique, the upstream and downstream signals are allocated to occupy the left and right sideband of the optical carrier respectively, and thus the RB noise can be easily removed by a simple optical filter in the receiver. In our experiment, the carrier-to-signal power ratio (CSPR) and the frequency gap between the upstream and downstream signals are investigated. Furthermore, bidirectional transmission of 60 Gbps SSB-Nyquist-16QAM signals over 50 km 7-core fiber are successfully achieved, and the frequency gap between the upstream and downstream signals is only 3 GHz.

A Bidirectional FSO Communication Employing Phase Modulation Scheme and Remotely Injection-Locked DFB LD

Abstract: A bidirectional free-space optical (FSO) communication through a 600-m free-space transmission is built, employing a phase modulation (PM) scheme and a remotely injection-locked distributed feedback laser diode (DFB LD) for presentation. With optimum injection locking, a DFB LD is excellent for duplex transceiver operations. An injection-locked DFB LD not only operates as a PM-to-intensity modulation converter with an optical detector, but also functions as an upstream optical carrier. To be the first one of employing a remotely injection-locked DFB LD to detect a phase-modulated 25-Gb/s/25-GHz four-level pulse amplitude modulation (PAM4) passband signal, the DFB LD with remote injection locking is successfully intensity-modulated with an upstream 25-Gb/s non-return-to-zero (NRZ) signal. Good bit error rate performance and clear PAM4/NRZ eye diagrams show that this FSO communication can use a remotely injection-locked DFB LD to detect the downstream phase-modulated PAM4 signal and concurrently deliver an upstream intensity-modulated NRZ signal. This bidirectional 25-Gb/s/25-GHz (downstream)/25-Gb/s (upstream) FSO communication is prominent due to its enhancement in two-way high-speed optical wireless communications.

Calibration-free and bias-drift-free microwave characterization of dual-drive Mach–Zehnder modulators using heterodyne mixing

Abstract: An electrical method is proposed for the microwave characterization of dual-drive Mach–Zehnder modulators based on heterodyne mixing. The proposed method utilizes the heterodyne products between the two-tone modulated optical sidebands and frequency-shifted optical carrier, and achieves calibration-free and bias-drift-free microwave measurement of dual-drive Mach–Zehnder modulators with high resolution electrical-domain techniques. Our method avoids the extra calibration for the photodetector and reduces half the bandwidth requirement for the photodetector and the electrical spectrum analyzer through carefully choosing a half frequency relationship of the two-tone modulation. Moreover, our measurement avoids the bias drifting problem due to the insensitivity to the bias phase of the modulator under test. The frequency-dependent modulation depths and half-wave voltages are measured for a commercial dual-drive Mach–Zehnder modulator with our method, which agree well with the results obtained by the conventional optical spectrum analysis method.

Tunable single passband microwave photonic filter based on DFB-SOA-assisted optical carrier recovery

Abstract: A tunable single passband microwave photonic filter (MPF) based on a distributed-feedback semiconductor optical amplifier (DFB-SOA) is proposed and experimentally demonstrated in this paper The fundamental principle is to recover the suppressed optical carrier from a passband optical filter by the wavelength-selective amplification of the DFB-SOA A microwave signal is then generated by beating the recovered optical carrier with the phase modulated lower sideband and thus a MPF is achieved with the shape of the passband optical filter which is mapped from optical domain to electrical domain By tuning the central wavelength of the passband optical filter, a single passband MPF with frequency tuning range from 5 to 35 GHz is obtained The 3-dB bandwidth and the out-of-band suppression ratio are measured to be 4 GHz and 20 dB, respectively

Dual-mode laser diode carrier with orthogonal polarization and single-mode modulation for remote-node heterodyne MMW-RoF.

Abstract: A remote-node heterodyne millimeter-wave radio-over-fiber (MMW-RoF) link was proposed by a dual-mode optical carrier with orthogonal polarizations and single-wavelength modulation, which effectively suppresses the chromatic dispersion and four-wave mixing. For optical wireline transmission, the bit error rate (BER) of a 25-km single-mode fiber (SMF) transmitted baseband 24-Gbit/s 64-QAM OFDM can be improved to 5.9×10−4 with an error vector magnitude (EVM) of 7.1%. Moreover, the beat 35-GHz MMW carrier with a 32-dB carrier-to-noise ratio was generated for wireless transmission. The BER and EVM of passband 8-Gbit/s 16-QAM OFDM at 35-GHz MMW carrier were 3.4×10−3 and 17.1%, respectively, after 25-km SMF and 1.6-m free-space transmissions.