Donald B Stephens

US Patent:

60944633, Jul 25, 2000

Filed:

Jun 30, 1998

Appl. No.:

9/109307

Inventors:

Donald R. Stephens - Clearwater FL
William Mosley - Seminole FL

Assignee:

Raytheon Company - Lexington MA

International Classification:

H04L 2722
H04L 2708

US Classification:

375326

Abstract:

A noise estimator for threshold correction of a receiver includes a low pass filter to remove wideband noise from an input signal that includes a signal component and a noise component. The output of the wideband filter is applied to a square-law power detector having an output applied to an envelope detector. The output of the envelope detector is the instantaneous envelope of the input signal and is applied to a low pass filter to perform time averaging and is also applied to a differential network. The output of the low pass filter is a signal representing a time averaged statistical envelope representing the statistical mean of the instantaneous envelope of the input signal. This signal is also applied to the differential network that generates a signal representing the difference in the instantaneous envelope of the input signal and the time averaged statistical envelope signal. This difference signal is applied to a square-law power detector and then to a low pass filter for time averaging. An output of the low pass filter is a signal representing an estimate of the noise component of the input signal.

US Patent:

39692175, Jul 13, 1976

Filed:

Oct 7, 1974

Appl. No.:

5/513009

Inventors:

Tilak V. Bommaraju - Grand Island NY
Donald E. Stephens - Grand Island NY

Assignee:

Hooker Chemicals & Plastics Corporation - Niagara Falls NY

International Classification:

C25B 1106
C25B 134
C25B 1010

US Classification:

204290F

Abstract:

An improved electrode, useful as an anode for the electrolysis of brines comprises an electrically conductive substrate having adhered thereto and extending over at least a portion of the surface thereof, a coating of mixed oxides comprising about 10 to about 80 mole percent indium oxide and about 10 to about 90 mole percent of a platinum group metal oxide. Up to about 20 mole percent of tin oxide may be incorporated in the coating to lower the electrical resistivity thereof.

US Patent:

58780904, Mar 2, 1999

Filed:

Jan 21, 1998

Appl. No.:

/010322

Inventors:

Donald R. Stephens - Clearwater FL

Assignee:

E-Systems, Inc. - Dallas TX

International Classification:

H04D 324

US Classification:

375326

Abstract:

A receiver carrier synchronization apparatus and method for carrier synchronization with a received signal having a known data pattern preamble uses a "punctured" preamble for making carrier synchronization estimates thereby reducing the number of receivers required. The known data pattern preamble of the received signal is processed with a local reference signal and a differentiated replica of the known data pattern preamble to generate an error signal. The error signal is selectively sampled in the time domain in accordance with a puncture scheme, and the sampled error signal is used to generate the local reference signal in a closed loop. The received signal is processed with the local reference signal and a replica of the known data pattern preamble to generate a synchronization estimate signal.

US Patent:

40122964, Mar 15, 1977

Filed:

Oct 30, 1975

Appl. No.:

5/627428

Inventors:

Donald E. Stephens - Grand Island NY
Tilak V. Bommaraju - Grand Island NY

Assignee:

Hooker Chemicals & Plastics Corporation - Niagara Falls NY

International Classification:

C25B 1106
C25B 1110
C25B 1308
C25B 146

US Classification:

204 98

Abstract:

An electrode, for use in electrolytic processes, especially as an anode for use in the electrolysis of aqueous solutions of alkali metal halides, comprises a valve metal substrate coated on at least a portion of the surface thereof with a mixed oxide of hafnium and ruthenium wherein the molar ratio of ruthenium:hafnium is from about 0. 25 to about 4.

US Patent:

59011734, May 4, 1999

Filed:

Dec 9, 1996

Appl. No.:

8/762593

Inventors:

Donald R. Stephens - Clearwater FL
William Mosley - Seminole FL

Assignee:

Raytheon Company - Lexington MA

International Classification:

H04B 1700
H04L 2708

US Classification:

375227

Abstract:

A noise estimator for threshold correction of a receiver includes a low pass filter to remove wideband noise from an input signal that includes a signal component and a noise component. The output of the wideband filter is applied to a square-law power detector having an output applied to an envelope detector. The output of the envelope detector is the instantaneous envelope of the input signal and is applied to a low pass filter to perform time averaging and is also applied to a differential network. The output of the low pass filter is a signal representing a time averaged statistical envelope representing the statistical mean of the instantaneous envelope of the input signal. This signal is also applied to the differential network that generates a signal representing the difference in the instantaneous envelope of the input signal and the time averaged statistical envelope signal. This difference signal is applied to a square-law power detector and then to a low pass filter for time averaging. An output of the low pass filter is a signal representing an estimate of the noise component of the input signal.

US Patent:

39502406, Apr 13, 1976

Filed:

May 5, 1975

Appl. No.:

5/574477

Inventors:

Arthur S. Cookfair - Tonawanda NY
Donald E. Stephens - Grand Island NY
Tilak V. Bommaraju - Grand Island NY

Assignee:

Hooker Chemicals & Plastics Corporation - Niagara Falls NY

International Classification:

C25B 126
C25B 134
C25B 1110

US Classification:

204290F

Abstract:

An electrode useful as an anode for the electrolysis of aqueous solutions of ionizable chemical compounds, and especially the electrolysis of brines comprises an electroconductive substrate, such as a valve metal having a coating thereon of electroconductive tin oxide containing about 0. 1 to about 15 mole percent of niobium based on the moles of tin. An additional electrocatalytic phase may be present as a minor component of the tin oxide coating and/or as a coating thereon.

US Patent:

59057629, May 18, 1999

Filed:

Jan 21, 1998

Appl. No.:

9/009975

Inventors:

Donald R. Stephens - Clearwater FL

Assignee:

Raytheon Company - Lexington MA

International Classification:

H03D3/24

US Classification:

375326

Abstract:

A receiver carrier synchronization apparatus and method for carrier synchronization with a received signal having a known data pattern preamble uses a "punctured" preamble for making carrier synchronization estimates thereby reducing the number of receivers required. The known data pattern preamble of the received signal is processed with a local reference signal and a differentiated replica of the known data pattern preamble to generate an error signal. The error signal is selectively sampled in the time domain in accordance with a puncture scheme, and the sampled error signal is used to generate the local reference signal in a closed loop. The received signal is processed with the local reference signal and a replica of the known data pattern preamble to generate a synchronization estimate signal.

US Patent:

57906025, Aug 4, 1998

Filed:

Dec 15, 1995

Appl. No.:

8/573421

Inventors:

Donald R. Stephens - Clearwater FL

Assignee:

E-Systems, Inc. - Dallas TX

International Classification:

H04L 2722
H04L 700

US Classification:

375326

Abstract:

A receiver carrier synchronization apparatus and method for carrier synchronization with a received signal having a known data pattern preamble uses a "punctured" preamble for making carrier synchronization estimates thereby reducing the number of receivers required. The known data pattern preamble of the received signal is processed with a local reference signal and a differentiated replica of the known data pattern preamble to generate an error signal. The error signal is selectively sampled in the time domain in accordance with a puncture scheme, and the sampled error signal is used to generate the local reference signal in a closed loop. The received signal is processed with the local reference signal and a replica of the known data pattern preamble to generate a synchronization estimate signal.