Patents by Inventor Arthur James Lowery

Arthur James Lowery has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 9614617
    Abstract: An apparatus (104) mitigates cross-channel nonlinear distortion of an optical signal (138) carried on one of a plurality of wavelength channels (118) in a wavelength division multiplexed (WDM) transmission system (100). The apparatus includes a first optical receiver (126) which is arranged to detect a measure (134) of aggregate optical power of the plurality of wavelength channels. A nonlinear dispersion compensator includes means (144) for applying a phase modulation to the optical signal in proportion to the measure of aggregate optical power.
    Type: Grant
    Filed: October 6, 2010
    Date of Patent: April 4, 2017
    Assignee: Ofidium Pty. Ltd.
    Inventors: Arthur James Lowery, Liang Bangyuan Du
  • Patent number: 9294216
    Abstract: A method for transmitting digital information having a predetermined bit-rate (B) via a nonlinear optical channel includes determining a combination of transmission parameters comprising a number (N) of subcarriers, an information symbol rate (S) for each subcarrier, and a number (b) of bits per symbol on each subcarrier, such that B=NSb. An optical signal is generated comprising the plurality (N) of orthogonal optical subcarriers. Each subcarrier is modulated to carry a proportion (Sb/B) of the total bit-rate (B) of the digital information. The optical signal is then transmitted to a corresponding optical receiver via the nonlinear optical channel. The received signal has a measurable signal quality (Q) which is a function of the transmission parameters (N, S, b).
    Type: Grant
    Filed: March 2, 2012
    Date of Patent: March 22, 2016
    Assignee: OFIDIUM PTY. LTD.
    Inventors: Arthur James Lowery, Liang Bangyuan Du
  • Patent number: 9236951
    Abstract: An optical signal (116) is modulated with a transmitted electrical signal comprising an information-bearing component (122) and a pilot tone (120) having a predetermined frequency. Transmission of the signal results in distortion, including nonlinear optical transmission impairments. A method of receiving the signal includes detecting the optical signal to produce a received electrical signal (X) comprising a distorted variant of the transmitted electrical signal. The pilot tone is extracted from the received electrical signal using a filtering operation (308) having a predetermined characteristic, and a compensation signal determined based upon the extracted pilot tone. The compensation signal is applied to the received electrical signal (X) to produce a compensated signal (Y) having reduced distortion.
    Type: Grant
    Filed: December 19, 2011
    Date of Patent: January 12, 2016
    Assignee: OFIDIUM PTY. LTD.
    Inventors: Arthur James Lowery, Liang Bangyuan Du
  • Patent number: 9002210
    Abstract: An equalizer (200) for equalization of a signal transmitted via an optical fiber link from a transmitter to a corresponding receiver employs a backpropagation model (300) which comprises one or more sequential segments collectively representing an inverse fiber link. Each sequential segment comprises a linear backpropagation element (304), and a non-linear backpropagation element (306) having an associated compensation bandwidth (312). The equalizer (200) generates a distortion-mitigated signal by computing, for each sequential segment in turn, a first linear compensated signal from a signal input to the segment in accordance with the linear backpropagation element (304), and a non-linear compensated signal from the first linear compensated signal in accordance with the non-linear backpropagation element (306).
    Type: Grant
    Filed: March 1, 2011
    Date of Patent: April 7, 2015
    Assignee: Ofidium Pty. Ltd.
    Inventors: Arthur James Lowery, Liang Bangyuan Du
  • Publication number: 20140294393
    Abstract: A method for transmitting digital information having a predetermined bit-rate (B) via a nonlinear optical channel includes determining a combination of transmission parameters comprising a number (N) of subcarriers, an information symbol rate (S) for each subcarrier, and a number (b) of bits per symbol on each subcarrier, such that B=NSb. An optical signal is generated comprising the plurality (N) of orthogonal optical subcarriers. Each subcarrier is modulated to carry a proportion (Sb/B) of the total bit-rate (B) of the digital information. The optical signal is then transmitted to a corresponding optical receiver via the nonlinear optical channel. The received signal has a measurable signal quality (Q) which is a function of the transmission parameters (N, S, b).
    Type: Application
    Filed: March 2, 2012
    Publication date: October 2, 2014
    Applicant: Ofidium Pty Ltd.
    Inventors: Arthur James Lowery, Liang Bangyuan Du
  • Publication number: 20140286642
    Abstract: An optical signal (116) is modulated with a transmitted electrical signal comprising an information-bearing component (122) and a pilot tone (120) having a predetermined frequency. Transmission of the signal results in distortion, including nonlinear optical transmission impairments. A method of receiving the signal includes detecting the optical signal to produce a received electrical signal (X) comprising a distorted variant of the transmitted electrical signal. The pilot tone is extracted from the received electrical signal using a filtering operation (308) having a predetermined characteristic, and a compensation signal determined based upon the extracted pilot tone. The compensation signal is applied to the received electrical signal (X) to produce a compensated signal (Y) having reduced distortion.
    Type: Application
    Filed: December 19, 2011
    Publication date: September 25, 2014
    Applicant: Ofidium Pty Ltd
    Inventors: Arthur James Lowery, Liang Bangyuan Du
  • Patent number: 8655177
    Abstract: A method of generating an information-bearing optical signal (614) from input digital information (602) includes generating (604, 606) an information-bearing electrical signal comprising an in-phase (I) component and a quadrature (Q) component. Each of the components has a predetermined baseband bandwidth requirement (B). The I and Q signal components are combined (610) with corresponding I and Q components of a radio frequency (RF) carrier (608). The carrier has a central frequency greater than the signal bandwidth requirement (B). An optical source is modulated (612) with the combined I and Q signal and carrier components, in order to produce a modulated optical signal (614) which comprises an optical carrier corresponding with the RF carrier, and substantially only a single information-bearing optical sideband in an optical frequency domain, corresponding with the information-bearing electrical signals. Transmitters implementing the method are also disclosed.
    Type: Grant
    Filed: February 27, 2009
    Date of Patent: February 18, 2014
    Assignee: Ofidium Pty. Ltd.
    Inventors: Arthur James Lowery, Liang Bangyuan Du
  • Publication number: 20130156443
    Abstract: An equaliser (200) for equalisation of a signal transmitted via an optical fibre link from a transmitter to a corresponding receiver employs a backpropagation model (300) which comprises one or more sequential segments collectively representing an inverse fibre link. Each sequential segment comprises a linear backpropagation element (304), and a non-linear backpropagation element (306) having an associated compensation bandwidth (312). The equaliser (200) generates a distortion-mitigated signal by computing, for each sequential segment in turn, a first linear compensated signal from a signal input to the segment in accordance with the linear backpropagation element (304), and a non-linear compensated signal from the first linear compensated signal in accordance with the non-linear backpropagation element (306).
    Type: Application
    Filed: March 1, 2011
    Publication date: June 20, 2013
    Applicant: OFIDIUM PTY LTD
    Inventors: Arthur James Lowery, Liang Bangyuan Du
  • Publication number: 20120263461
    Abstract: An apparatus (104) mitigates cross-channel nonlinear distortion of an optical signal (138) carried on one of a plurality of wavelength channels (118) in a wavelength division multiplexed (WDM) transmission system (100). The apparatus includes a first optical receiver (126) which is arranged to detect a measure (134) of aggregate optical power of the plurality of wavelength channels. A nonlinear dispersion compensator includes means (144) for applying a phase modulation to the optical signal in proportion to the measure of aggregate optical power.
    Type: Application
    Filed: October 6, 2010
    Publication date: October 18, 2012
    Applicant: Ofidium Pty Ltd
    Inventors: Arthur James Lowery, Liang Bangyuan Du
  • Patent number: 8233799
    Abstract: A method and apparatus for receiving digital information transmitted via an optical signal over an optical channel wherein the optical signal includes an optical carrier (402) and at least one information-bearing optical sideband (404) in the optical frequency domain. The transmitted optical power is distributed between the optical carrier (402) and the optical side band (404). The received optical signal is processed in order to increase the received power in the optical carrier (402) relative to the power in the optical side-band (404). The processed optical signal is detected in order to produce a corresponding electrical signal. The electrical signal is then processed in order to recover the digital information.
    Type: Grant
    Filed: October 15, 2008
    Date of Patent: July 31, 2012
    Assignee: Ofidium Pty, Ltd.
    Inventor: Arthur James Lowery
  • Patent number: 8111993
    Abstract: A system (100) for transmitting digital information includes a transmitting apparatus (102) for generating an optical signal bearing digital information, a dispersive optical channel (104), and a receiving apparatus (110) for receiving the optical signal. The dispersive optical channel (104) is disposed to convey the optical signal from the transmitting apparatus (102) to the receiving apparatus (110). The transmitting apparatus includes an encoder (114) for encoding digital information into a series of blocks, each including a plurality of data symbols corresponding with one or more bits of digital information. A signal generator (118) generates a time-varying signal corresponding with each of said blocks.
    Type: Grant
    Filed: October 12, 2006
    Date of Patent: February 7, 2012
    Assignee: Ofidium Pty Ltd.
    Inventors: Arthur James Lowery, Jean Armstrong
  • Patent number: 8112001
    Abstract: A method of transmitting information over a non-linear optical channel includes the step (152) of generating an information-bearing signal, preferably an OFDM signal, which includes a plurality of closely-spaced sub-carriers in the frequency domain. A time-varying phase modulation is determined (154), which is a first function, and preferably a linear function, of the transmitted optical power corresponding with the information-bearing signal. The information-bearing signal and the time-varying phase modulation are applied (156) to an optical source in order to generate a corresponding transmitted optical signal having substantially the stated transmitted optical power characteristic. The first function of transmitted optical power is selected so as to mitigate the effect of the non-linearity of the optical channel upon the transmitted optical signal.
    Type: Grant
    Filed: December 20, 2007
    Date of Patent: February 7, 2012
    Assignee: Ofidium Pty, Ltd.
    Inventors: Arthur James Lowery, Liang Bangyuan Du
  • Patent number: 8107826
    Abstract: A method of communicating digital information over a dispersive optical channel includes encoding the digital information into a plurality of data blocks, each of which includes a number of bits of the information. A time-varying electrical signal is generated which corresponds with each of said data blocks. The time-varying electrical signal is applied to an optical transmitter (122) to generate an optical signal which includes an asymmetrically amplitude limited transmitted signal modulated onto an optical carrier. The optical signal is then transmitted over the dispersive optical channel (106). At a receiving apparatus (104) the optical signal is detected to produce an electrical signal which corresponds with the asymmetrically amplitude limited transmitted signal.
    Type: Grant
    Filed: September 1, 2006
    Date of Patent: January 31, 2012
    Assignee: Ofidium Pty Ltd.
    Inventors: Jean Armstrong, Arthur James Lowery
  • Patent number: 8107827
    Abstract: An apparatus and method are provided for receiving an optical signal having an optical carrier component and at least one information-bearing optical sideband. In general, an optical filter arrangement (110) is used to separate the optical carrier component from the information-bearing optical sideband. First and second optical splitters (126, 128) divide the optical power in the optical carrier and the optical sideband, respectively, into corresponding sub-components. The sub-components of the optical carrier have substantially orthogonal polarisation states, which is an optional characteristic of the sideband sub-components. First and second optical coupling devices (142, 144) respectively each combine one of the optical carrier sub-components with a corresponding one of the optical sideband sub-components. Optical detectors (158, 160) detect the outputs of the combiners (142, 144).
    Type: Grant
    Filed: February 20, 2009
    Date of Patent: January 31, 2012
    Assignee: Ofidium Pty, Ltd.
    Inventors: Brendon James Schmidt, Arthur James Lowery, Jean Armstrong
  • Publication number: 20110286747
    Abstract: A method of generating an information-bearing optical signal (614) from input digital information (602) includes generating (604, 606) an information-bearing electrical signal comprising an in-phase (I) component and a quadrature (Q) component. Each of the components has a predetermined baseband bandwidth requirement (B). The I and Q signal components are combined (610) with corresponding I and Q components of a radio frequency (RF) carrier (608). The carrier has a central frequency greater than the signal bandwidth requirement (B). An optical source is modulated (612) with the combined I and Q signal and carrier components, in order to produce a modulated optical signal (614) which comprises an optical carrier corresponding with the RF carrier, and substantially only a single information-bearing optical sideband in an optical frequency domain, corresponding with the information-bearing electrical signals. Transmitters implementing the method are also disclosed.
    Type: Application
    Filed: February 27, 2009
    Publication date: November 24, 2011
    Applicant: OFIDIUM PTY LTD
    Inventors: Arthur James Lowery, Liang Bangyuan Du
  • Publication number: 20110013914
    Abstract: A method and apparatus for receiving digital information transmitted via an optical signal over an optical channel wherein the optical signal includes an optical carrier (402) and at least one information-bearing optical sideband (404) in the optical frequency domain. The transmitted optical power is distributed between the optical carrier (402) and the optical side band (404). The received optical signal is processed in order to increase the received power in the optical carrier (402) relative to the power in the optical side-band (404). The processed optical signal is detected in order to produce a corresponding electrical signal. The electrical signal is then processed in order to recover the digital information.
    Type: Application
    Filed: October 15, 2008
    Publication date: January 20, 2011
    Applicant: Ofidium Pty Ltd
    Inventor: Arthur James Lowery
  • Publication number: 20100316393
    Abstract: An apparatus and method are provided for receiving an optical signal having an optical carrier component and at least one information-bearing optical sideband. In general, an optical filter arrangement (110) is used to separate the optical carrier component from the information-bearing optical sideband. First and second optical splitters (126, 128) divide the optical power in the optical carrier and the optical sideband, respectively, into corresponding sub-components. The sub-components of the optical carrier have substantially orthogonal polarisation states, which is an optional characteristic of the sideband sub-components. First and second optical coupling devices (142, 144) respectively each combine one of the optical carrier sub-components with a corresponding one of the optical sideband sub-components. Optical detectors (158, 160) detect the outputs of the combiners (142, 144).
    Type: Application
    Filed: February 20, 2009
    Publication date: December 16, 2010
    Applicant: Ofidium Pty. Ltd.
    Inventors: Brendon James Schmidt, Arthur Jame Lowery, Jean Armstrong
  • Patent number: 7693429
    Abstract: A method of transmitting digital information over a dispersive optical channel includes encoding the digital information into a series of data blocks, wherein each block comprises a plurality of substantially orthogonal frequency domain subcarriers. Each data block is then divided into at least two frequency bands, each band comprising a plurality of contiguous subcarriers. A frequency/time transformation is then performed, in order to form a corresponding plurality of transformed bands, each transformed band comprising a sequence of time domain data samples. A time delay is applied to at least one of the transformed bands relative to at least one other of the transformed bands. The bands are then combined to produce an electrical signal waveform embodying the digital information. Finally, an optical source is modulated using the electrical signal waveform, to produce a corresponding optical signal for transmission over the dispersive optical channel.
    Type: Grant
    Filed: April 13, 2009
    Date of Patent: April 6, 2010
    Assignee: Ofidium Pty., Ltd.
    Inventor: Arthur James Lowery
  • Publication number: 20090220239
    Abstract: A method of communicating digital information over a dispersive optical channel includes encoding the digital information into a plurality of data blocks, each of which includes a number of bits of the information. A time-varying electrical signal is generated which corresponds with each of said data blocks. The time-varying electrical signal is applied to an optical transmitter (122) to generate an optical signal which includes an asymmetrically amplitude limited transmitted signal modulated onto an optical carrier. The optical signal is then transmitted over the dispersive optical channel (106). At a receiving apparatus (104) the optical signal is detected to produce an electrical signal which corresponds with the asymmetrically amplitude limited transmitted signal.
    Type: Application
    Filed: September 1, 2006
    Publication date: September 3, 2009
    Applicant: Monash University
    Inventors: Jean Armstrong, Arthur James Lowery
  • Publication number: 20090169213
    Abstract: A system (100) for transmitting digital information includes a transmitting apparatus (102) for generating an optical signal bearing digital information, a dispersive optical channel (104), and a receiving apparatus (110) for receiving the optical signal. The dispersive optical channel (104) is disposed to convey the optical signal from the transmitting apparatus (102) to the receiving apparatus (110). The transmitting apparatus includes an encoder (114) for encoding digital information into a series of blocks, each including a plurality of data symbols corresponding with one or more bits of digital information. A signal generator (118) generates a time-varying signal corresponding with each of said blocks.
    Type: Application
    Filed: October 12, 2006
    Publication date: July 2, 2009
    Applicant: Monash University
    Inventors: Arthur James Lowery, Jean Armstrong