Philip Anthony Dafesh from 1140 5Th St, Manhattan Beach, CA 90266, age 60

Resumes

Distinguished Engineer

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Location:

Los Angeles, CA

Industry:

Defense & Space

Work:

The Aerospace Corporation
Distinguished Engineer
The Aerospace Corporation Aug 2016 - Oct 2019
Principal Engineer
The Aerospace Corporation Feb 2007 - Aug 2016
Director
The Aerospace Corporation Feb 2004 - Feb 2007
Associate Director
The Aerospace Corporation Feb 2000 - Feb 2004
Section Manager

Education:

University of California, Los Angeles 1990 - 1993
Doctorates, Doctor of Philosophy, Electronics, Electronics Engineering, Philosophy University of California, Los Angeles 1987 - 1990
Masters, Master of Science In Electrical Engineering, Electronics Engineering, Electronics

Skills:

Systems Engineering
Engineering Management
Global Positioning System
Signal Processing
Software Defined Radio
Gps Devices
Gps Navigation
Receivers
Transmitters
Wireless Communications Systems
Interference Mitigation
Cellular Communications

Us Patents

Spread Spectrum Bit Boundary Correlation Search Acquisition System
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US Patent:

7042930, May 9, 2006
Filed:

Jun 6, 2002
Appl. No.:

10/165662
Inventors:

Philip A. Dafesh - Los Angeles CA, US
Assignee:

The Aerospace Corporation - El Segundo CA
International Classification:

H04B 1/69
H04B 1/00
US Classification:

375149, 375343, 375142, 375150
Abstract:

A multiple integration hypothesis C/A code acquisition system resolves bit boundaries using parallel correlators providing magnitude hypotheses during acquisition to reduce losses over the 20 ms integration period to improve the performance and sensitivity of C/A code receivers to achieve low C/No performance using inexpensive, imprecise oscillators and long noncoherent dwell periods, well suited for in-building, multipath, and foliage attenuated GPS signaling applicable to E911 communications with several dB of additional improvement in receiver sensitivity due to the ability to detect bit synchronization during acquisition.

Quadrature Product Subcarrier Modulation System
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US Patent:

7120198, Oct 10, 2006
Filed:

May 26, 1999
Appl. No.:

09/318560
Inventors:

Philip A. Dafesh - Los Angeles CA, US
Tien M. Nguyen - Placentia CA, US
Assignee:

The Aerospace Corporation - El Segundo CA
International Classification:

H04L 5/12
H04L 23/02
US Classification:

375261, 375473, 370487, 370229
Abstract:

A coherent adaptive subcarrier modulation system applies subcarrier modulation to quadrature modulated signals with constant envelope modulation suitable for efficient sinewave and squarewave subcarrier modulations. The quadrature subcarrier enables the addition of new signals to the in-phase and quadrature phase signals with spectral isolation in the Global Position System while maintaining a constant envelop amplitude.

Gated Time Division Multiplexed Spread Spectrum Correlator
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US Patent:

7130326, Oct 31, 2006
Filed:

Mar 13, 2002
Appl. No.:

10/098792
Inventors:

Rouh T. Bow - Rolling Hills Estates CA, US
Philip A. Dafesh - Los Angeles CA, US
Assignee:

The Aerospace Corporation - El Segundo CA
International Classification:

H04B 1/69
H04B 7/212
H03D 1/02
US Classification:

375130, 375142, 375147, 375150, 375343, 375316, 370294, 370347, 370345, 370337
Abstract:

A civil moderate (CM) code and a civil long (CL) code are time division multiplex (TDM) as a combined code having alternating code chips that spectrum spread a transmitted signal received by a receiver tracking the spectrum spreading code using a two-level correlator operating with +1 and −1 values to alternately correlate the received CM and CL code chips using a gating signal to gate by time the correlation of the two codes. The time gated two-level TDM correlation can be used in communication receivers, such as GPS receivers, receiving the TDM spectrum spreading codes.

Direct-Sequence Spread-Spectrum Optical-Frequency-Shift-Keying Code-Division-Multiple-Access Communication System
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US Patent:

7200342, Apr 3, 2007
Filed:

Jun 6, 2002
Appl. No.:

10/165661
Inventors:

Philip A. Dafesh - Los Angeles CA, US
Assignee:

The Aerospace Corporation - El Segundo CA
International Classification:

H04B 10/04
US Classification:

398182, 398183
Abstract:

A direct-sequence-spread-spectrum (DSSS) optical-frequency-shift-keying (OFSK) code-division-multiple-access (CDMA) communication system is adapted with optical transmitters and receivers for preferred use fiber optical communication systems where modulated data and pseudorandom noise (PRN) codes are encoded in the optical domain and communicated over optical paths for increasing system capacity in wide area optical networks.

Cognitive Anti-Jam Receiver Systems And Associated Methods
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US Patent:

8515335, Aug 20, 2013
Filed:

Nov 30, 2009
Appl. No.:

12/627875
Inventors:

Philip Anthony Dafesh - Manhattan Beach CA, US
Raghavendra S. Prabhu - Los Angeles CA, US
Esteban Luis Valles - Los Angeles CA, US
Assignee:

The Aerospace Corporation - El Segundo CA
International Classification:

H04K 3/00
H04B 17/00
H04M 11/00
H04W 4/00
US Classification:

455 1, 455 6711, 4554261, 455403, 4554221
Abstract:

Cognitive anti-jam receiver systems and associated methods are provided. The systems and methods may include a signal analysis module that processes a baseband signal to determine one or more signal characteristics of the baseband signal, the baseband signal comprising at least a desired signal; a cognitive decision unit that receives the one or more signal characteristics from the signal analysis module, and generates at least one first adaptive parameter; and at least one anti-jam processing module that processes the baseband signal to generate a modified signal that reduces an impact of at least one jammer signal on a quality of reception of the desired signal from the baseband signal, where processing by the at least one anti-jam processing module may be based at least in part on the received at least one first adaptive parameter from the cognitive decision unit.

Phase-Optimized Constant Envelope Transmission (Pocet) Method, Apparatus And System
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US Patent:

20110051783, Mar 3, 2011
Filed:

Aug 25, 2009
Appl. No.:

12/547383
Inventors:

Charles Robert Cahn - Manhattan Beach CA, US
Philip A. Dafesh - Manhattan Beach CA, US
International Classification:

H04B 1/707
H04L 27/12
H04B 1/04
US Classification:

375146, 375302, 455110, 375E01002
Abstract:

An apparatus and method for generating a composite signal includes electronics configured to modulate a carrier utilizing a finite set of composite signal phases to generate a composite signal, the finite set of composite signal phases being determined through an optimization process that minimizes a constant envelope for the phase modulated carrier, subject to constraints on desired signal power levels of the signals to be combined and either zero or one or more relative phase relationships between the signals. The apparatus and method can be extended to generating an optimized composite signal of different frequencies.

Coherent Adaptive Subcarrier Modulation Method
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US Patent:

6430213, Aug 6, 2002
Filed:

May 26, 1999
Appl. No.:

09/318561
Inventors:

Philip A. Dafesh - Los Angeles CA
Assignee:

The Aerospace Corporation - El Segundo CA
International Classification:

H04B 1707
US Classification:

375146, 375298
Abstract:

A generalized quadrature product subcarrier modulation system applies subcarrier modulation to quadrature modulated signals with constant envelope modulation suitable for efficient sinewave and squarewave subcarrier modulations. The quadrature subcarrier modulation enables the addition of new signals to the in-phase and quadrature phase signals with spectral isolation while maintaining a constant amplitude waveform.

Narrowband Antijam Signaling System (Nass) And Device
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US Patent:

20210011120, Jan 14, 2021
Filed:

Jun 24, 2020
Appl. No.:

16/911315
Inventors:

- El Segundo CA, US
Philip A. DAFESH - Manhattan Beach CA, US
International Classification:

G01S 7/36
G01S 7/02
G01S 13/76
H04K 3/00
H04B 1/10
G06F 17/14
Abstract:

A narrowband AJ signaling system includes an AJ processor placed between a high precision analog-to-digital (ADC) converter and a narrowband digital receiver. In another example, the AJ processor is placed between the high precision ADC and a digital-to-analog converter (DAC). The AJ processor of either example may suppress the jammer power down to the level of the noise floor of the system.