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.

Optical transmission device

Abstract: An optical transmission device is provided with an external optical modulator including three or more Mach-Zehnder interferometers and outputs a single-sideband optical intensity-modulated signal with suppressed optical carrier component, wherein an optical carrier component and an unnecessary one sideband component contained in the outputted optical signal are suppressed. A light branching section ( 51 ) branches an optical signal outputted by an external optical modulator ( 4 ) into two signals. A photodetector section ( 52 ) converts one of the optical signals to an electric signal. An optical carrier component extracting section ( 54 ) extracts an optical carrier component signal that is in the vicinity of a frequency f 1 from the electric signal. An optical carrier component suppressing section ( 56 ) applies a bias voltage for suppressing the optical carrier component to the external optical modulator ( 4 ) based on the signal level of the optical carrier component. A vestigial sideband component extracting section ( 57 ) extracts a vestigial sideband component signal in the vicinity of a frequency 2×f 1 from the electric signal. A vestigial sideband component suppressing section ( 59 ) applies a bias voltage for suppressing an unnecessary one sideband component to the external optical modulator ( 4 ) based on the signal level of the vestigial sideband component.

Method for linearizing an unbalanced Mach Zehnder optical frequency discriminator

Abstract: An unbalanced Mach Zehnder optical frequency discriminator is linearized to suppress third order nonlinear distortion. An optical carrier that is modulated in optical frequency is input to an unbalanced Mach Zehnder interferometer to discriminate RF information signals carried on the carrier. The Mach Zehnder interferometer has an adjustable operating point. The operating point is adjusted to a point where the output intensity of the Mach Zehnder interferometer is no more than about ten percent of its maximum value. In order to avoid problems with second order distortion, the optical carrier is modulated with RF signals that do not occupy more than a single octave. The operating point of the device can be adjusted by adjusting an electrical bias thereof, by adjusting the wavelength of the optical carrier, or by adjusting the temperature of the device.

High-speed optical transceiver for infiniband and ethernet

Abstract: The present invention provides a high-speed 100G optical transceiver for InfiniBand and Ethernet with associated mapping to frame InfiniBand and Ethernet into GFP-T. The optical transceiver utilizes an architecture which relies on standards-compliant (i.e., multi-sourced) physical client interfaces. These client interfaces are back-ended with flexible, programmable Field Programmable Gate Array (FPGA) modules to accomplish either InfiniBand or Ethernet protocol control, processing, re-framing, and the like. Next, signals are encoded with Forward Error Correction (FEC) and can include additional Optical Transport Unit (OTU) compliant framing structures. The resulting data is processed appropriately for the subsequent optical re-transmission, such as, for example, with differential encoding, Gray encoding, I/Q Quadrature encoding, and the like. The data is sent to an optical transmitter block and modulated onto an optical carrier. Also, the same process proceeds in reverse on the receive side.

A Full-Duplex Radio-Over-Fiber Link Based on a Dual-Polarization Mach–Zehnder Modulator

Abstract: A simple and low-cost full-duplex radio-over-fiber (RoF) link implementing wavelength reuse for short-range applications is proposed and demonstrated based on a dual-polarization Mach–Zehnder modulator (DPol-MZM). In the center unit, a continuous-wave optical carrier is sent to a DPol-MZM to generate an optical signal with data modulation along one polarization direction and an unmodulated optical carrier along the other orthogonal polarization direction. In the remote antenna unit, a polarization beam splitter is used to separate the modulated signal for downstream service and the unmodulated optical carrier for upstream signal remodulation. A proof-of-concept experiment is carried out. Performance of the established full-duplex RoF link operated at 18 GHz is investigated. The measured bit error rate and the error vector magnitude confirm that the proposed architecture is a promising candidate for future high-speed and low-cost short-range applications.

Design and performance of the bidirectional optical single-sideband modulator

Abstract: We present a detailed study of the design and performance of the bidirectional optical single-sideband modulator (BOSSM). This is a new scheme to achieve optical single-sideband modulation (OSSB) that uses a standard single-electrode Mach-Zehnder modulator (MZ-EOM) and passive fiber-optic components. The design is based on a novel technique to operate electrooptic modulators in which the radio frequency (RF) electrode is bidirectionally driven. The fundamentals of this bidirectional operation are analyzed thoroughly and it is found that it requires the use of a wide-bandwidth MZ-EOM with an electrode design that provides good velocity match between the optical and microwave modes. Deriving the expressions for the optical field and power at the output of the BOSSM, the OSSB operation is shown to be independent of the MZ-EOM bias. Therefore, the optical modulation depth at the output of the device can be enhanced using minimum transmission biasing to provide suppression of the optical carrier. Moreover, it is found that the second-order distortion is unaffected by the MZ-EOM bias; hence the technique can be applied to multi-octave bandwidth systems. Finally, the performance of the BOSSM is evaluated using a prototype based on a commercial 10 Gb/s MZ-EOM. The experimental characterization of the electrooptical parameters of this device reveals that the RF electrode design is not optimized for bidirectional operation. Therefore, the performance of the prototype is limited by the particular MZ-EOM deployed. However, sideband suppression over 10 dB is measured for most frequencies up to millimeter-waves, with peaks in the 20 dB to 30 dB range for narrow bands. This performance has enabled the demonstration of a 22-km fiber link transmitting a 29-GHz subcarrier conveying binary phase-shift keying modulated data at 622 Mb/s. The BOSSM reduces the dispersion-induced power penalty in the link to less than 1.5 dB. Furthermore, the bit error rate of the link is increased by five orders of magnitude using the carrier suppression technique.