Dual-level package
Granted: February 12, 2013
Patent Number:
8373996
Consistent with an aspect of the present disclosure, a package is provided that has a carrier and first and second substrates provided on the carrier. Conductive traces are provided on the first substrate (upper traces) and below it (lower traces) to provide two levels of electrical connectivity to a photonic integrated circuit (PIC) provided on the second substrate. As a result, an increased number of connections can be made to the PIC in a relatively small package, while maintaining…
Interleaved correction code transmission
Granted: February 5, 2013
Patent Number:
8370706
An optical device transmits ECC codewords using an interleaved technique in which a single ECC codeword is transmitted over multiple optical links. In one particular implementation, the device may include an ECC circuit configured to supply ECC codewords in series, the codewords being generated by the ECC circuit based on input data and each of the codewords including error correction information and a portion of the data. The device may further include a serial-to-parallel circuit…
XML over TCP management protocol with tunneled proxy support and connection management
Granted: January 29, 2013
Patent Number:
8364841
Network elements, which are network nodes in a transmission network, implement a proprietary XML agent which supports an XML over TCP network management protocol. The protocol permits tunneling of proxy management traffic, with connection management support, to a privately addressed subtending network element. This tunneling is performed via a publicly addressable gateway network element device without the need for configuration at the element management system software application…
Method and system for control of communication equipment based on a bit error rate derived from a frame alignment signal
Granted: January 22, 2013
Patent Number:
8359500
Consistent with the present disclosure, circuitry may be provided in an optical receiver that can determine a bit error rate (BER) associated with an incoming signal by dividing the number of errored bits in a frame alignment signals (FAS) by the number of bits in the FAS. Accordingly, although an optical signal may be severely degraded and forward error correction (FEC) cannot be performed, a BER may be obtained if the FAS can be identified. The BER can then be used in a feedback loop…
Integrated circuit with pins at multiple edges of a chip
Granted: December 25, 2012
Patent Number:
8339799
An improved integrated circuit (IC) layout is described that provides conductive pads on opposite sides of a substrate. The conductive pads provide for connectivity to the chip in different chip orientations. Accordingly, multiple chips having the same layout can be provided in a package, instead of providing each chip with a different layout. Since the same layout may be used for each chip, manufacturing costs are reduced.
Method, system, and apparatus for blind equalization of BPSK signals
Granted: December 18, 2012
Patent Number:
8335440
A system, method, and apparatus is disclosed for enabling a constant modulus algorithm (CMA) to be reliably used for blind equalization training of an equalizer. According to one embodiment, received signals in a binary phase shift keying (BPSK) format are converted to a quadrature phase shift keying (QPSK) format, to which CMA processing can be reliably applied for equalization. According to another aspect of this embodiment, the equalized QPSK signals are rotated to convert the signals…
Method and apparatus for controlling an output of an optical amplifier
Granted: December 4, 2012
Patent Number:
8325413
A system is provided that includes optical amplifiers provided upstream from an optical add-drop multiplexer (OADM). One of the optical amplifiers may be a Raman amplifier that supplies amplified light to another optical amplifier, such as an erbium doped fiber amplifier (EDFA), which, in turn, further amplifies and feeds the light to an input of the OADM. During turn-up, for example, the EDFA may initially be disabled, the power of the pump lasers of the Raman amplifier may be gradually…
Polarization insensitive optical circuit
Granted: November 20, 2012
Patent Number:
8314988
One embodiment contemplates a polarization insensitive optical circuit constructed of an input/output signal separator, such as an optical circulator or a 1×2 or 2×2 coupler or N×M coupler, a polarization sensitive operator, and a polarization rotator reflector. In an alternate embodiment, the invention contemplates a polarization insensitive optical circuit including a polarization rotator reflector, and a polarization sensitive operator which may include, for example, a first…
Transmitter photonic integrated circuit (TxPIC) chip
Granted: October 30, 2012
Patent Number:
8300994
A photonic integrated circuit (PIC) chip comprising an array of modulated sources, each providing a modulated signal output at a channel wavelength different from the channel wavelength of other modulated sources and a wavelength selective combiner having an input optically coupled to received all the signal outputs from the modulated sources and provide a combined output signal on an output waveguide from the chip. The modulated sources, combiner and output waveguide are all integrated…
Temporal alignment of data unit groups in a switch
Granted: October 30, 2012
Patent Number:
8300479
Consistent with the present disclosure, a plurality of FIFO buffers, for example, are provided in a switch, which also includes a switch fabric. Each of the plurality of FIFOs is pre-filled with data for a duration based on a skew or time difference between the time that a data unit group is supplied to its corresponding FIFO and a reference time. The reference time is the time, for example, after a delay period has lapsed following the leading edge of a synch signal, the timing of which…
Variable optical attentuator (VOA) having an absorber for receiving residual light outputfrom the VOA
Granted: October 30, 2012
Patent Number:
8299417
A variable optical attenuator (VOA), which may include a Mach-Zehnder interferometer, is configured such that a substantial part of an input signal is output on a first waveguide, and a relatively small part of the input signal may be output on a second waveguide due to manufacturing process variations and/or other non-idealities. Such residual or extraneous light may interfere with light in the first waveguide, especially if the VOA is integrated on substrate. Accordingly, consistent…
Flat-top response arrayed waveguide grating
Granted: October 23, 2012
Patent Number:
8295661
An optical system is disclosed. The optical system includes first and second waveguides, a first dispersive element, and a coupler. The first waveguide is configured to support a first mode and a second mode of an optical input signal. The second mode being of a higher order than the first mode. The second waveguide has an input and an output and is configured to receive a portion of the optical input signal. The first dispersive element is disposed along a length of one of the first or…
Transmitter photonic integrated circuit
Granted: October 2, 2012
Patent Number:
8280255
The present invention provides a system, apparatus and method to provide for amplification at various points along one or more optical paths of a photonic integrated circuit. According to various embodiments of the invention, the photonic integrated circuit includes a plurality of optical devices having associated characteristics which may have lead to optical signal degradation. One or more optical amplifiers provided along one or more optical paths of the photonic integrated circuit…
Universal digital framer architecture for transport of client signals of any client payload and format type
Granted: September 25, 2012
Patent Number:
8274892
A transmission network includes network elements which accept client signals to be transported over a transmission network, particularly an optical transmission network, each of the client signals having one of a plurality of payload rates. The client signals are digitally mapped into first transport frames and, subsequently, digitally mapped into second transport frames for transport across the network infrastructure. The second transport frames having a universal frame rate throughout…
Method, system, and apparatus for filter implementation using hermitian conjugates
Granted: September 25, 2012
Patent Number:
8275267
Filter implementation using Hermitian conjugates and time division multiplexing (TDM) is disclosed to more efficiently compensate for chromatic dispersion of optical signals transmitted over a fiber optic medium. Embodiments for an input, filter, and output sections of a Digital Signal Processor (DSP) are described. The disclosed methods, and corresponding apparatus and systems enables a substantial reduction in the complexity of the hardware needed to implement CD compensation in the…
Photodiode isolation in a photonic integrated circuit
Granted: September 18, 2012
Patent Number:
8269297
Consistent with the present disclosure, a current blocking layer is provided between output waveguides carrying light to be sensed by the photodiodes in a balanced photodetector, and the photodiodes themselves. Preferably, the photodiodes are provided above the waveguides and sense light through evanescently coupling with the waveguides. In addition, the current blocking layer may include alternating p and n-type conductivity layers, such that, between adjacent ones of such layers, a…
Optical modulator drive circuit
Granted: September 18, 2012
Patent Number:
8269546
A modulator drive circuit provides a modulator drive signal, representative of a data waveform, to modulate an optical signal for transport across a network infrastructure. The modulator drive circuit includes a broadband Bias-T circuit insensitive to the frequency range of the data waveform. The Bias-T circuit provides for an adjustable bias level to maintain proper operation of a modulator used to modulate the optical signal. One or more modulator drive circuits may be provided on a…
Communication network with skew determination
Granted: September 4, 2012
Patent Number:
8259703
Embodiments of the present invention determine skew relative to a plurality of communication paths on a network system. The network is a wavelength division multiplexed optical transport network. The plurality of communication paths involves different signal and path attributes such as a plurality of carrier wavelengths, optical carrier groups, physical communication paths (different nodes, different fibers along a same path, or any combination of the foregoing), or any other…
Photonic integrated circuit employing optical devices on different crystal directions
Granted: September 4, 2012
Patent Number:
8260094
Consistent with the present disclosure, various optical components are preferably arranged on the surface of a semiconductor substrate such that light propagates in certain components at a direction that is perpendicular to a direction of propagation in other components in order to improve performance and component density.
Photonic integrated circuit having bent active components
Granted: September 4, 2012
Patent Number:
8260096
Consistent with the present disclosure, the number of passive waveguides in a PIC are reduced by directly connecting active components to one another. Accordingly, optical signals propagating in the PIC may experience less loss, and, thus, improved performance may be achieved. In addition, active components may be bent or curved in order to obtain a more compact layout with greater device density. Reduced manufacturing costs can therefore be realized.
