Abstract: A system for the Raman amplification of mode-division multiplexed optical signals at the telecom wavelengths in multimode optical fibers, and a method. A mode-division multiplexer (105) is used at the input of a multimode fiber (107) to inject signals (101), and continuous-wave pump waves at lower wavelength (102), on the different transverse modes of the fiber. A second mode-division multiplexer (106) is used at the output of the fiber to extract the amplified signals (103). The amplification of one or more signals is accomplished by inter-modal and intra-modal stimulated Raman scattering occurring between the fiber transverse modes carrying the signals and those carrying the pumps.

Abstract: The present invention relates to a system for detecting the inclination of one or more light beams, having at least one sharp colour transition, emitted by one or more light sources, in particular PAPIs or APAPIs, comprising measuring means (103) for measuring an inclination, and optoelectronic means (120, 121) for acquiring images which means are capable to be inclinated by first powered means (122), the inclination measuring means (103) being integrally coupled to optoelectronic means (120, 121) so as to measure the inclination of the latter, and wherein the system further comprises electronic processing means (62) capable to control the first powered means (122) an the basis of the images acquired by the optoelectronic means (120, 121) so that, when the system carries out a detection of the inclination of said one or more light beams, said at least one sharp colour transition appears in at least one corresponding predetermined position of said acquired images, said electronic processing means (62) reading

Abstract: An apparatus and a method for transmitting at least a digital optical signal with return-to-zero phase-shift keying, employing a single optical modulator with dual-drive design, the encoded optical signal having improved spectral efficiency and performances and being generated by transmitters with simplified scheme; an optical communication system comprising the transmitting apparatus, a transmission line and an apparatus to receive the optical signal.

Abstract: An apparatus for transmitting at least a digital optical signal with a simultaneous modulation of the amplitude and the phase, the said encoded optical signal having improved spectral efficiency and performances, and being generated by transmitters with simplified scheme; an optical communication system comprising the said apparatus, a transmission line and an apparatus to receive the said optical signal.

Abstract: An apparatus and a method for transmitting at least a digital optical signal with return-to-zero phase-shift keying, employing a single optical modulator with dual-drive design, the said encoded optical signal having improved spectral efficiency and performances, and being generated by transmitters with simplified scheme; an optical communication system comprising the said apparatus, a transmission line and an apparatus to receive the said optical signal.

Abstract: An apparatus for transmitting at least a digital optical signal with a simultaneous modulation of the amplitude and the phase, the said encoded optical signal having improved spectral efficiency and performances, and being generated by transmitters with simplified scheme; an optical communication system comprising the said apparatus, a transmission line and an apparatus to receive the said optical signal.

Abstract: An optical communication system comprising an apparatus to transmit at least a digital optical signal modulated with a first encoded sequence of optical dark pulses and with a second encoded sequence of optical phase, an optical transmission line and an apparatus to receive, the said optical signal having high spectral efficiency.