Abstract: A fiber optic transmitter comprising: a digital driver adapted to adjust the rise time and fall time of a digital input signal; an optical source adapted to receive the digital signal and produce a frequency modulated optical signal; and an optical spectrum reshaper adapted to convert the frequency modulated optical signal to an amplitude modulated optical signal. A method for transmitting an optical signal through a fiber comprising: receiving a digital input signal; adjusting the rise time and fall time of the digital input signal so as to produce an adjusted digital input signal; passing the adjusted digital input signal to an optical source so as to produce a frequency modulated optical signal; passing the frequency modulated optical signal through an optical spectrum reshaper so as to convert the frequency modulated optical signal to an amplitude modulated optical signal; and passing the amplitude modulated signal into the fiber.
Type:
Grant
Filed:
December 17, 2004
Date of Patent:
April 8, 2008
Assignee:
Azna LLC
Inventors:
Daniel Mahgerefteh, Yasuhiro Matsui, Parviz Tayebati
Abstract: There is provided a fiber optic transmission system, comprising: an optical signal source adapted to produce a frequency modulated signal; and a multi-ring resonator optical spectrum reshaper (OSR) adapted to convert the frequency modulated signal into a substantially amplitude modulated signal. And there is provided a method for transmitting an optical signal through a fiber comprising: producing a frequency modulated signal; passing the frequency modulated signal through a multi-ring resonator optical spectrum reshaper (OSR) so as to convert the frequency modulated signal into a substantially amplitude modulated signal; and passing the substantially amplitude modulated signal into the fiber.
Abstract: This invention provides a system that combines a wavelength multiplexer with an FM discriminator for chirp reduction and wavelength locker in a filter to produce a wavelength division multiplexed signal with reduced chirp. A partially frequency modulation laser signal is converted into a substantially amplitude modulation laser signal. This conversion increases the extinction ratio of the input signal and further reduces the chirp. A wavelength division multiplexing (WDM) method is used for transmitting high capacity information through fiber optics systems where digital information is carried on separate wavelengths through the same fiber. Separate transmitters normally generate their respective signals that are transmitted at different wavelengths. These signals are then combined using a wavelength multiplexer to transmit the high capacity information through the fiber optic system.
Abstract: This invention provides a flat dispersion frequency discriminator (FDFD) capable of having a substantially flat dispersion with either a positive or negative dispersion along the spectrum region of the discriminator. This way, a FDFD may not cause substantial distortion of the intensity patter of its output to minimize the occurrence distortion due to overshooting or undershooting of the intensity pattern depending on the relative spectral alignment of the laser output relative to the filter transmission.
Type:
Grant
Filed:
October 6, 2003
Date of Patent:
May 30, 2006
Assignee:
Azna LLC
Inventors:
Daniel Mahgerefteh, Duncan John William Walker, Roeland Nuyts