The first Brazilian high speed integrated 100G-DPQPSK transmitter on a 4 × 3 mm silicon photonic chip is presented. The novel photonic component allows optical signal generation of advanced modulation formats in 25GHz bandwidth. Furthermore, in this paper we also present our vision on required integrated photonics targeting 400G optical transmission systems.
An electro-optical sensor system for monitoring synchronous compensators in the electrical distribution network is presented. The fiber-optic sensor system is based on two main technologies: optical bend loss sensors for monitoring the brush wear and, free-space optics to determine the dust accumulation from brush wear. Both techniques are characterized to monitor the parameters by means of simple optical power readings. In order to avoid optical power fluctuations in the fiber optics link from interrogation system to the synchronous compensators, bend-loss insensitive fibers are used. The low-cost interrogation system consists on one laser, optical splitters and 80 photodetectors to independently monitor each one of the synchronous compensators’s brushes. This setup ensures an ease installation and avoid cascaded fault that a serial configuration could originates, thus increasing reliability of the sensor system.
In this work we propose an asynchronous FBG interrogation system for rotating machines. The method was developed to
monitor temperature and deformation on hydrogenerator rotors, but can be easily used to monitor any other rotating
machine. The proposed scheme relays in a simplified interrogator, which need not be synchronized with the optical
collimation system. The system was tested successfully for various rotating velocities from 0 to 800 RPM.
Frequently, assessment and monitoring of mechanical (acoustic) vibrations is necessary in large structures. Cost and reliability are major issues for field-deployment. We present a simple, compact and reliable optical accelerometer designed and constructed in our labs, capable of consistent measurement of vibrations in low and intermediate acoustic ranges (few Hz to few kHz). The principle of operation is based on the variation of the optical signal power coupled between singlemode fibers fixed in the optical sensor head. The device sensitivity has a lower limit to accelerations below 1g, and surprising upper value above 180 m/s2 (18g).