Paul N Freeman

US Patent:

6388806, May 14, 2002

Filed:

Feb 28, 2001

Appl. No.:

09/797043

Inventors:

Paul N. Freeman - Saratoga CA
Stephen G. Grubb - Columbia MD
Daniel A. Ratoff - San Jose CA
David G. Mehuys - Sunnyvale CA

Assignee:

SDL, Inc. - San Jose CA

International Classification:

H01S 300

US Classification:

3593413, 3593411

Abstract:

A multistage optical fiber amplifier (OFA) system is designed to be upgraded with the addition of pump power when signal capacity of an optical communication link is correspondingly increased. The system includes a gain flattening filter (GFF) that remains valid when the system is upgraded because of the system design. Also disclosed are ways to enhance the GFF as well as control the channel signal gain tilt as well as adjust the external gain uniformity to be the same for an assembly line of OFA systems.

US Patent:

6760152, Jul 6, 2004

Filed:

Oct 11, 2002

Appl. No.:

10/269925

Inventors:

Daniel Ratoff - San Jose CA
Paul Nathan Freeman - Saratoga CA

Assignee:

JDS Uniphase Corporation - San Jose CA

International Classification:

H01S 300

US Classification:

3593413, 35934131

Abstract:

The present application relates to a doped fiber amplifier having an increased dynamic range, and particularly for laser pump sources and a method of pumping erbium doped fiber amplifiers over a greater dynamic range. In a multi-channel optical system, optical amplifiers must be able to provide gain over a larger range of signal powers, the dynamic range corresponding to the number of channels in the link. The present invention has found that the dynamic range of an EDFA can be significantly increased by using pulse width modulation to pulse pump current at or near the minimum current stability threshold, in order to produce lower power output. The duty cycle of the pulsed current is selected to achieve a time-averaged operating condition taking advantage of the relatively long relaxation time of the erbium. Thus the time averaged pump power can be reduced in a linear fashion well below the capability of a continuous wave system.

US Patent:

7680364, Mar 16, 2010

Filed:

Jun 29, 2006

Appl. No.:

11/427624

Inventors:

Alan C. Nilsson - Mountain View CA, US
Robert W. Smith - Sonoma CA, US
Yishai Kagan - Sunnyvale CA, US
Paul N. Freeman - Saratoga CA, US

Assignee:

Infinera Corporation - Sunnyvale CA

International Classification:

G02B 6/12

US Classification:

385 14, 372 26, 372 32, 372 20, 372 501, 398 1, 398 9, 398 91

Abstract:

A transmissive active channel element is provided in each signal channel of a monolithic multi-channel TxPIC where each channel also includes a modulated source. The active channel element functions both as a power control element for both monitoring and regulating the output channel signal level of each signal channel and as a modulator for channel wavelength tagging or labeling to provide for wavelength locking the modulated sources. The power regulating function is also employed to control the channel signal power outputs of each channel to be uniform across the channel signal array. All of these functions are carried out by a feedback loop utilizing digital signal processing.

US Patent:

8155488, Apr 10, 2012

Filed:

Jul 22, 2009

Appl. No.:

12/507763

Inventors:

Alan C. Nilsson - Mountain View CA, US
Robert W. Smith - Sonoma CA, US
Yishai Kagan - Sunnyvale CA, US
Paul N. Freeman - Saratoga CA, US

Assignee:

Infinera Corporation - Sunnyvale CA

International Classification:

G02B 6/12

US Classification:

385 14, 372 32, 398 91, 385 24, 385 31, 385 46

Abstract:

A transmissive active channel element is provided in each signal channel of a monolithic multi-channel TxPIC where each channel also includes a modulated source. The active channel element functions both as a power control element for both monitoring and regulating the output channel signal level of each signal channel and as a modulator for channel wavelength tagging or labeling to provide for wavelength locking the modulated sources. The power regulating function is also employed to control the channel signal power outputs of each channel to be uniform across the channel signal array. All of these functions are carried out by a feedback loop utilizing digital signal processing.

US Patent:

8385742, Feb 26, 2013

Filed:

Dec 23, 2009

Appl. No.:

12/645770

Inventors:

Xinghua Yang - San Jose CA, US
Paul N. Freeman - Saratoga CA, US
Alan C. Nilsson - Mountain View CA, US
Jeffrey S. Bostak - San Martin CA, US
Vincent G. Dominic - Dayton OH, US
Parmijit Samra - Fremont CA, US
James Stewart - San Mateo CA, US

Assignee:

Infinera Corporation - Sunnyvale CA

International Classification:

H04J 14/02

US Classification:

398 79, 398162, 398167, 375354, 375375

Abstract:

Consistent with the present disclosure, clock-and-data recovery (CDR) circuitry and driver circuitry are provided on a chip that is separate from the driver circuitry, thereby reducing the amount of power consumed by the driver circuitry and simplifying system design. In one example, timing of the ERZ signals is controlled by a feedback loop that adjusts the phase of a data carrying signal relative to a clock signal, such that the phase has a desired value. Timing of the ERZ signals may thus be adjusted to minimize errors.

US Patent:

8565602, Oct 22, 2013

Filed:

Mar 23, 2009

Appl. No.:

12/409067

Inventors:

Brian Dean Taylor - San Jose CA, US
Alan C. Nilsson - Mountain View CA, US
Konstantin Saunichev - San Jose CA, US
Paul N. Freeman - Saratoga CA, US

Assignee:

Infinera Corporation - Sunnyvale CA

International Classification:

H04J 14/02

US Classification:

398 82, 398 85

Abstract:

Consistent with the present disclosure, a transmitter is provided that includes first and second stages of wavelength locking circuitry. The first stage includes a tunable optical filter that sweeps through the spectrum of a WDM signal at a predetermined rate. A first photodiode senses a tapped portion of the output of the tunable filter. The remaining light is fed to the second stage, which includes a second optical filter, typically having a fixed transmission characteristic. A second photodiode senses the light that passes through the second filter. By sweeping the WDM spectrum the tunable filter can be used to identify the peaks in the WDM spectrum, with each peak corresponding to an optical signal wavelength and occurring at a particular time interval during the sweep. Thus, each optical signal wavelength can be associated with a particular time interval in the sweep, and, if no peak is identified during the sweep, a fault can be identified as either a laser failure or that the optical signal wavelength has drifted or “hopped” to another optical signal wavelength. Once having identified that an optical signal has hopped, the optical source outputting that optical signal can be appropriately controlled to output light at the correct wavelength.

US Patent:

20130220876, Aug 29, 2013

Filed:

Jan 25, 2013

Appl. No.:

13/750594

Inventors:

Paul Freeman - Branchburg NJ, US

Assignee:

MARS, INC. - McLean VA

International Classification:

B65D 25/00
B31B 1/00

US Classification:

206736, 493 52

Abstract:

A display carton with controlled deflection zones that are designed to control the weak points of the carton and to direct deformation of the carton when compressed. As more and more weight is added to the top surface of a carton that embodies a deflection zone, the deflection zone may initially resist crushing. As even more weight is added, the deflection zone may start to give way. The deflection zone helps to controlling the image of the container, even if the container becomes crushed. The display carton may incorporate different styles of deflection zones, and the display carton may incorporate the deflection zones at a variety of locations of the carton. Additionally, the controlled deflection zones can be incorporated into many different styles of display cartons, shipping containers, boxes and the like, including shipping containers that can be converted easily from a shipping configuration to a display configuration.

US Patent:

59873035, Nov 16, 1999

Filed:

May 29, 1996

Appl. No.:

8/655016

Inventors:

Niloy Kumar Dutta - Annandale NJ
Paul Nathan Freeman - New Providence NJ

Assignee:

AT&T Corp. - New York NY

International Classification:

H04N 7173

US Classification:

455 31

Abstract:

A wireless transmission and reception system includes a mixing section using a phase shift keying or quadrature amplitude modulation scheme to modulate a baseband signal, representing voice or data, onto a carrier frequency within the range of standard (cable television format) AM-VSB frequencies. A combiner section combines the modulated carrier signal into a channel of a multiplexed cable television (CATV) signal having two or more channels. The CATV signal is used to modulate a laser source. The laser source generates a laser signal based on the CATV signal. The laser signal is optically coupled into a bidirectional fiber link. The fiber link transmits the laser signal and ultimately converts the laser signal into the electrical CATV signal. A splitting section coupled to the bidirectional fiber link splits the modulated carrier signal from the CATV signal. A demodulating section coupled to the splitting section recovers the baseband signal from the modulated carrier signal.