Herwig W Kogelnik

US Patent:

6380533, Apr 30, 2002

Filed:

Sep 3, 1999

Appl. No.:

09/390033

Inventors:

Robert Meachem Jopson - Rumson NJ
Herwig Werner Kogelnik - Rumson NJ
Lynn Elizabeth Nelson - Eatontown NJ

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

G02F 101

US Classification:

250225, 25022717, 356364

Abstract:

The present invention consists of a method and apparatus for measuring first and higher order PMD vectors in optical fibers. For each first-order PMD vector determination, two distinct polarization states are sequentially injected into an optical device under test for each of a pair of frequencies and +. A Stokes vector s representing the first polarization state must not be parallel or anti-parallel to a Stokes vector s representing the second polarization state, but the relative angle between s and s need not be known. The frequency interval is large to obtain a high signal-to-noise ratio. Thus, four light beams are injected, the first at frequency and polarization s , the second at frequency and polarization s , the third at frequency + and polarization s , and the fourth light at frequency + and polarization s. The output polarizations of these beams are measured and four corresponding output Stokes vectors are determined. A first-order PMD vector is then calculated from the four input Stokes vectors and four output Stokes vectors.

US Patent:

6385356, May 7, 2002

Filed:

Dec 22, 1999

Appl. No.:

09/468968

Inventors:

Robert M. Jopson - Rumson NJ
Herwig Kogelnik - Rumson NJ
Lynn E. Nelson - Monmouth Beach NJ

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

G02B 600

US Classification:

385 11, 359161, 359156

Abstract:

In an optical fiber transmission system, higher order PMD compensation is realized with a sweeper device at the input to the fiber which converts the polarization of the light beam into a frequency dependent polarization whose rate of change is similar to the rate of change of one of the PSPs of the fiber. The frequency dependent polarization of the light beam is then aligned with one of the frequency-dependent PSPs at the input of the fiber. Furthermore, differential group delay dispersion for a given frequency can be reduced by employing a chromatic dispersion compensator prior to the receiver end of the fiber transmission system. Control of the polarization of the light beam can be facilitated by monitoring PMD in the system, or alternatively, monitoring an effect of PMD in the system, such as bit error rates.

US Patent:

6385357, May 7, 2002

Filed:

Mar 22, 2000

Appl. No.:

09/533044

Inventors:

Robert M. Jopson - Rumson NJ
Herwig Kogelnik - Rumson NJ
Lynn E. Nelson - Monmouth Beach NJ

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

G02B 600

US Classification:

385 11, 385123, 359161

Abstract:

In an optical fiber transmission system, higher order PMD compensation is realized at the output of the transmission fiber. A compensator is placed at the output of the transmission fiber whose PMD vector is equal in magnitude and opposite in direction to the PMD vector at the output of the transmission fiber. The compensator PMD vector sweeps at a rate that matches the frequency sweep rate of the PMD vector at the fiber output. To compensate for second order PMD while avoiding the introduction of higher order PMD effects, a planar sweep is advantageously employed. A polarization pair controller is employed in advance of the compensator to align the PMD vector at the compensator input with the PMD vector at the fiber output so that the two cancel as well as to align the rotational axis of the compensator PMD vector with the rotational axis of the fiber PMD vector. The system may also include a monitoring device to monitor the compensation of fiber PMD, to determine the need for adjustments to the system.

US Patent:

6519027, Feb 11, 2003

Filed:

Mar 8, 2000

Appl. No.:

09/520537

Inventors:

James Power Gordon - Rumson NJ
Robert Meachem Jopson - Rumson NJ
Herwig Werner Kogelnik - Rumson NJ
Lynn E. Nelson - Monmouth Beach NJ

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

G01N 2100

US Classification:

356 731

Abstract:

Four different light signals, all of the same optical frequency, but, having different states of polarization, are transmitted through an optical device and the mean signal delay of each of the light signals is measured. Calculations, based upon the relationship, = -Â {right arrow over ( )}Â{overscore (s)}, describing the polarization dependence of (a measured mean signal delay) through the device as a function of (a polarization independent delay component of the device), {right arrow over ( )} (the PMD vector at the device input) and {overscore (s)} (the input Stokes vector of the light signal), yield the PMD of the device. Also, by comparing data taken at adjacent wavelengths, the chromatic dispersion of the optical device can be accurately measured even in the presence of PMD.

US Patent:

6538787, Mar 25, 2003

Filed:

Sep 24, 1999

Appl. No.:

09/404892

Inventors:

Lothar Moeller - Hazlet NJ
Herwig Kogelnik - Rumson NJ

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

H04B 1000

US Classification:

359161, 359156, 359249, 385 11, 372 25, 372 27

Abstract:

A polarization mode dispersion (PMD) emulator may include one or more modular âcellsâ that emulate PMD. Each of the cells may include optical delay and phase modulation components. The optical delay and/or the phase modulation components may be adjusted to account for differences in PMD and two or more of the cells may be combined to further adjust the overall PMD of the apparatus. Similarly, a PMD compensator may include one or more modular âcellsâ that compensate for PMD, with each of the cells including optical delay and phase modulation components. The optical delay and/or the phase modulation components may be adjusted to compensate for various PMD values and two or more of the cells may be combined to further adjust the overall PMD compensation of the apparatus. The PMD compensator apparatus may be used to compensate for PMD in wideband applications, such as wavelength division multiplexed (WDM) systems.

US Patent:

6684031, Jan 27, 2004

Filed:

Jun 18, 1998

Appl. No.:

09/099503

Inventors:

Herwig W. Kogelnik - Rumson NJ
Martin C. Nuss - Fair Haven NJ
Ashok V. Krishnamoorthy - Middletown NJ

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

H04J 1408

US Classification:

398 99, 398100, 398101

Abstract:

A high-speed access data network in which upstream and downstream traffic is logically or physically separated. The network can use the Ethernet media access control (MAC) layer protocol over distances that are much larger than conventionally possible with the Ethernet MAC layer protocol. In a configuration including a central office and multiple subscribers, the central office is removed from the collision domain, which can be made relatively small, without limiting the distance between the central office and the subscribers. The downstream data rate is not limited by the size of the collision domain and can thus be made almost arbitrarily large. Furthermore, by allowing a smaller collision domain, greater upstream data rates can be used. It is thus possible to use ubiquitous and inexpensive Ethernet LAN technology in highly cost-sensitive applications such as residential broadband access.

US Patent:

6768541, Jul 27, 2004

Filed:

Nov 27, 2002

Appl. No.:

10/306264

Inventors:

James Power Gordon - Rumson NJ
Robert Meachem Jopson - Rumson NJ
Herwig Werner Kogelnik - Rumson NJ
Lynn E. Nelson - Monmouth Beach NJ

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

G01N 2100

US Classification:

356 731

Abstract:

In one method, two light signals, of the same optical frequency, but having orthogonal states of polarization, are transmitted through an optical device and the mean signal delay of each of the light signals is measured. Calculations, based upon disclosed relationships, provide the polarization-independent delay ( ) through the optical device based upon the mean signal delays ( and ) of each of the light signals. By comparing at adjacent wavelengths, the chromatic dispersion of the optical device can be accurately measured even in the presence of PMD. In a second, similar method, four light signals of non-degenerate polarizations states that span Stokes space are utilized. In a modification of the above-described methods based on the measurement of pulse delays, the methods are adapted to the measurement of phase delays of sinusoidally modulated signals.

US Patent:

7590355, Sep 15, 2009

Filed:

Feb 28, 2006

Appl. No.:

11/307918

Inventors:

Robert Jopson - Rumson NJ, US
Herwig Kogelnik - Rumson NJ, US
Peter Winzer - Aberdeen NJ, US

Assignee:

Alcatel-Lucent USA Inc. - Murray Hill NJ

International Classification:

H04B 10/12
H04J 14/02
H04J 14/06

US Classification:

398148, 398 65, 398 81, 398152, 398159

Abstract:

A scheme is described for mitigating the effects of polarization-mode dispersion (PMD) in a wave-division multiplex (WDM) optical communication system having one or more transmission links with one or more quasi-static waveguide sections coupled by one or more non-static coupling sections. A transmitter is coupled to the transmission link and is adapted to transmit optical signals through the transmission link with wavelength channel spacing of the optical signals greater than about the PMD correlation bandwidth of at least one of the one or more quasi-static waveguide sections, so that the PMD induced outage probability for the system is optimized.

Author:

Herwig Kogelnik

ISBN #:

3527403205