Did You Know...
...that the x-ray was discovered purely by accident? When German physicist Wilhelm Konrad von Roentgen was experimenting with cathode rays in 1895, he put an activated Crookes tube in a book and went out to lunch. When he returned, he discovered that a key that had also been placed in the book showed up as an image on the developed film!
PatentStorm News
Make the Most of Our Site
See this month's Top Inventors and Most Cited Patents.
Stay on top of the latest innovations by subscribing to an RSS feed.
Registered users: Manage your profile.
| Number | Title | Issue Date |
| 8078054 | Apparatus and method for improving the tolerance of tone-based optical channel monitoring to stimulated Raman scattering For wavelength division multiplexing (WDM) communications, apparatus and methods are provided for performing tone-based optical channel monitoring that is less sensitive to stimulated Raman scattering (SRS). In tone-based optical channel monitoring, in which WDM cha... | 12/13/2011 |
| 8045853 | Mechanism for tracking wavelengths in a DWDM network without specialized hardware In one embodiment, techniques provide a mechanism for tracking wavelengths in a DWDM network. In particular, embodiments of the present invention also provide for connection tracking using a slowly modulated pilot tone in a DWDM network without dedicated hardware fo... | 10/25/2011 |
| 8032022 | Method for lightpath monitoring in an optical routing network A method and system for enabling lightpath monitoring in an optical network is disclosed. A single polarization modulator/scrambler introduces a pilot tone signal as an overlay on a plurality of optical signals on a source node and a performance monitoring unit dete... | 10/04/2011 |
| 7881611 | Optical fiber transmission system with noise loading A system and method for loading unutilized channels of a WDM system with noise to improve system performance. A transmitter amplifier may impart noise to unutilized channels by reducing amplifier input or providing feedback of the amplifier output. Noise signals may... | 02/01/2011 |
| 7869709 | Signal identification in optical communications networks Signals in an optical communications network, such as optical channels in an optical WDM network for example, are each identified by at least two low frequency dither tones with which the signal is modulated. The dither tones alternate with a predetermined periodici... | 01/11/2011 |
| 7783193 | Noise tone avoidance in optical networks Identification of optical channels in wavelength division multiplex (WDM) optical networks may be confounded by unwanted noise tones interfering with pilot/dither tones used for identifying optical channels. The invention describes a method of selecting pilot/dither... | 08/24/2010 |
| 7747166 | Pilot tones for optical signal wavelength identification and power measurement A method of optical communication includes providing a plurality of optical signals each associated with a distinct channel of a composite optical signal. A unique pilot tone signature is superimposed on each channel. The spectral composition of each signature inclu... | 06/29/2010 |
| 7734174 | System and method for a channel guard in a reconfigurable optical add-drop multiplexer The present invention provides a colorless multiplexing system and method for detecting new optical channels at power levels below that which would cause data errors in existing traffic, and on top of background light, thus, overcoming a known risk inherent in color... | 06/08/2010 |
| 7620318 | Optical transceiver using heterodyne detection and a transmitted reference clock A heterodyne communication system uses coherent data modulation that is resistant to phase noise. In particular, a pilot tone and reference clock signal are transmitted along with the modulated data to form the basis of an electrical demodulation local oscillator at... | 11/17/2009 |
| 7580632 | Method and apparatus for managing lightpaths in optically-routed networks A system and method that utilizes digital coding techniques to combine a high-rate data stream with a lower rate side data stream to produce a combined data stream in such a way that the side data can be extracted by an inexpensive, low-bandwidth receiver. The metho... | 08/25/2009 |
| 7505685 | Wavelength-division multiplex communication system and apparatus In the WDM communication system, in the absence of data to be transmitted on an optical channel, a pilot signal transmitting means transmits the channel-unique pilot signal data on the channel. A WDM communication apparatus on a receiving end detects the pilot signa... | 03/17/2009 |
| 7421199 | System and method for subcarrier modulation as supervisory channel An apparatus and method for processing a supervisory signal for optical network applications. The apparatus includes a subcarrier transmission system configured to receive a first supervisory signal and output a second supervisory signal, and an electrical-to-optica... | 09/02/2008 |
| 7418212 | Electrical detection of optical symbols A system and method for detecting digital symbols carried in a received optical signal. The system comprises a functional element operative to receive a stream of samples of an electrical signal derived from the received optical signal and to evaluate a non-linear f... | 08/26/2008 |
| 7412165 | DCC loop plug Systems and methods are disclosed for testing the functionality of a synchronous optical network having a data communication channel therein. The system includes a testing device connected to a network node within the synchronous optical network and a data communica... | 08/12/2008 |
| 7412166 | Pilot tones for optical signal wavelength identification and power measurement A method of optical communication includes providing a plurality of optical signals each associated with a distinct channel of a composite optical signal. A unique pilot tone signature is superimposed on each channel. The spectral composition of each signature inclu... | 08/12/2008 |
| 7389044 | Method and system for providing a signature signal in an optical network in the event of loss of a client An optical network including multiple nodes is subject to intermittent faults that may raise alarms in the system. The invention focuses on an optical network based on the Any rate architecture. A single fault such as a client failure at a node in such a network can... | 06/17/2008 |
| 7389045 | Apparatus and method for monitoring and compensating an optical signal Optical communication apparatuses and optical communication methods are provided. According to one aspect, an optical communication apparatus includes a communication path configured to communicate a first signal; a signal generator configured to provide a second si... | 06/17/2008 |
| 7376350 | Methods and apparatus for optical network management using pilot tones Methods and apparatus for managing an optical network using pilot tones are provided. One method includes selecting an optical path having a plurality of nodes from a database defining an expected optical network. A detected list of pilot tones associated with each ... | 05/20/2008 |
| 7369763 | Apparatus and method for monitoring an optical transmission line An apparatus and a method for monitoring an optical transmission line. An optical pilot signal of a predetermined duration is transmitted along said optical transmission line and a return signal is sent back from a signal returner along the same transmission line co... | 05/06/2008 |
| 7356261 | Optical wireless communications system An optical wireless communications system has a first optical wireless communications apparatus for transmitting a pilot beam and a second optical wireless communications apparatus for receiving the pilot beam to have a match for an optical axis of the first optical... | 04/08/2008 |
| 7346279 | Optical transceiver using heterodyne detection and a transmitted reference clock A heterodyne communication system uses coherent data modulation that is resistant to phase noise. In particular, a pilot tone and reference clock signal are transmitted along with the modulated data to form the basis of an electrical demodulation local oscillator at... | 03/18/2008 |
| 7336906 | Optical signal transmission An optical signal transmission apparatus for transmitting a plurality of data signals comprising a plurality of inputs for receiving a respective one of the data signals and delivering the respective data signal with a controlled phase and at a controlled data rate.... | 02/26/2008 |
| 7336903 | Optical wireless transmission apparatus There is disclosed an optical wireless transmission apparatus in which a pilot light emitting section of a receiving/emitting section sends a pilot light in a wavelength region of 930 nm to 960 nm to a target apparatus, and a light receiving device having a light re... | 02/26/2008 |
| 7324758 | Optical dispersion monitoring apparatus and optical dispersion monitoring method, and optical transmission system using same An optical dispersion monitoring apparatus and an optical dispersion monitoring method are capable of monitoring dispersion accurately with a simple construction in an optical transmission system using the same. To this end, the optical dispersion monitoring apparat... | 01/29/2008 |
| 7321728 | Optical waveform for use in a DWDM optical network and systems for generating and processing same An optical signal occupying one or more wavelengths. An optical data signal on each wavelength is modulated with a respective overhead (dither) signal, resulting in a respective dithered optical signal. The amplitude of a particular overhead signal used to modulate ... | 01/22/2008 |
| 7321730 | Method and apparatus for the transmission fault detection in an access network An optical network unit (ONU) interconnected by passive optical network (PON) equipment to an optical line terminal (OLT) is identified using secondary modulation of the optical carrier to impress an identifier of the ONU onto the carrier. This resolves a recurring ... | 01/22/2008 |
| 7313326 | Method to inject pilot tone into microcontroller-supervised DWDM transmitters The power of a digital signal such as an optical data stream is set via digital-to-analog converter having a reference input for connection to a DC reference signal. The pilot tone is injected into the reference input of the digital-to-analog converter. In the place... | 12/25/2007 |
| 7302182 | Methods and apparatus for sensing multiple wavelengths simultaneously in a single wavelength sensing device A method and system provide for sensing multiple wavelengths simultaneously in a single wavelength sensing device. The system may have a plurality of laser signals and a plurality of identifiable modulation signals. A respective laser signal of the plurality of lase... | 11/27/2007 |
| 7302178 | System and method for measuring power of optical signals carried over a fiber optic link A pilot tone generator receives optical energy from an optical communication medium carrying a plurality of optical signals. Each optical signal carries data modulated at a unique wavelength and further modulated with a unique identification signal. The identificati... | 11/27/2007 |
| 7283744 | Performance monitoring based on optical autocorrelation An optical performance monitor (OPM) adapted to (i) sample an autocorrelation function corresponding to an optical signal transmitted in an optical network and (ii) based on the sampling, characterize two or more impairments concurrently present in the optical signa... | 10/16/2007 |
| 7274874 | Idle-pattern output control circuit used in a Gigabit Ethernet-passive optical network An idle pattern output-control circuit used in a point-to-multipoint communication based Gigabit Ethernet-passive optical network (GE-PON) is provided. In a GE-PON having an optical-line terminal (OLT), a plurality of optical-network units (ONUs) connected to each o... | 09/25/2007 |
| 7274872 | System and method for subcarrier modulation as supervisory channel An apparatus and method for processing a supervisory signal for optical network applications. The apparatus includes a subcarrier transmission system configured to receive a first supervisory signal and output a second supervisory signal, and an electrical-to-optica... | 09/25/2007 |
| 7272308 | Method of WDM channel tagging and monitoring, and apparatus Provided is an optical apparatus and method wherein power transfer coefficients arising from SRS are measured at a designated co-location point and the power of dithers, which are impressed on the channels of a multiplexed optical signal propagating through the opti... | 09/18/2007 |
| 7263286 | Fast testing system for optical transceiver and testing method thereof The present invention provides a fast testing system and method for optical transceiver, which integrates multiple testing machines in the testing environment for the optical transceiver, so that the user can employ the testing system for optical transceiver for rap... | 08/28/2007 |
| 7263287 | Method and apparatus for assessing performance of optical systems An apparatus for accelerating assessment of an optical transmission system using Bit Error Rate (BER) tests calculates Q-factors for at least two different extinction ratios from measured test BER values, and extrapolates to determine a Q-factor for an operational e... | 08/28/2007 |
| 7248798 | Method and system for identification of channels in an optical network A method and system for identification of a channel in an optical network is provided. The channel is identified by the use of unique combinations of two or more low frequencies, or tones, modulated onto the channel and optionally, a network parameter associated wit... | 07/24/2007 |
| 7242863 | Method and system for coordinating and utilizing channel power information in an optical communications network A method of coordinating channel power information in a wavelength division multiplexed (WDM) optical communication system is disclosed. The method determines weighting values for each channel of the WDM signal based on channel launch powers. A source data object ma... | 07/10/2007 |
| 7231146 | Optical communication system Communicating a signal includes receiving the signal at a primary device of a switching system, where the primary device is associated with a primary path along which the signal is propagating. A primary overmodulation signal associated with the primary path is gene... | 06/12/2007 |
| 7212740 | Transmitter-receiver device and a communication system The invention concerns a transmitter-receiver device (A, B) which comprises a receiver unit (RXA) for receiving optical signals and transmitter unit (TXA) for transmitting optical signals. Furthermore, the transmitter-receiver device (A, B) comprises a supervising u... | 05/01/2007 |
| 7203420 | DCC loop plug Systems and methods are disclosed for testing the functionality of a synchronous optical network having a data communication channel therein. The system includes a testing device connected to a network node within the synchronous optical network and a data communica... | 04/10/2007 |
