Patents by Inventor Amr N. Hafez
Amr N. Hafez 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).
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Patent number: 9658107Abstract: A Micro-Electro-Mechanical System (MEMS) apparatus provides for self-calibration of mirror positioning of a moveable mirror of an interferometer. At least one mirror in the MEMS apparatus includes a non-planar surface. The moveable mirror is coupled to a MEMS actuator having a variable capacitance. The MEMS apparatus includes a capacitive sensing circuit for determining the capacitance of the MEMS actuator at multiple reference positions of the moveable mirror corresponding to a center burst and one or more secondary bursts of an interferogram produced by the interferometer based on the non-planar surface. A calibration module uses the actuator capacitances at the reference positions to compensate for any drift in the capacitive sensing circuit.Type: GrantFiled: April 15, 2016Date of Patent: May 23, 2017Assignee: Si-Ware SystemsInventors: Momen Anwar, Mostafa Medhat, Bassem Mortada, Ahmed Othman El Shater, Mina Gad Seif, Muhammed Nagy, Bassam A. Saadany, Amr N. Hafez
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Patent number: 9658053Abstract: A Micro-Electro-Mechanical System (MEMS) interferometer provides for self-calibration of mirror positioning of a moveable mirror. The moveable mirror is coupled to a MEMS actuator having a variable capacitance. The MEMS interferometer includes a capacitive sensing circuit for determining the capacitance of the MEMS actuator at two or more known positions of the moveable mirror and a calibration module for using the actuator capacitances at the known positions to compensate for any drift in the capacitive sensing circuit.Type: GrantFiled: January 28, 2014Date of Patent: May 23, 2017Assignee: Si-Ware SystemsInventors: Mostafa Medhat, Bassem Mortada, Ahmed Othman El Shater, Muhammed Nagy, Mina Gad Seif, Bassam A. Saadany, Amr N. Hafez
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Publication number: 20160231172Abstract: A Micro-Electro-Mechanical System (MEMS) apparatus provides for self-calibration of mirror positioning of a moveable mirror of an interferometer. At least one mirror in the MEMS apparatus includes a non-planar surface. The moveable mirror is coupled to a MEMS actuator having a variable capacitance. The MEMS apparatus includes a capacitive sensing circuit for determining the capacitance of the MEMS actuator at multiple reference positions of the moveable mirror corresponding to a center burst and one or more secondary bursts of an interferogram produced by the interferometer based on the non-planar surface. A calibration module uses the actuator capacitances at the reference positions to compensate for any drift in the capacitive sensing circuit.Type: ApplicationFiled: April 15, 2016Publication date: August 11, 2016Inventors: Mostafa Medhat, Bassem Mortada, Ahmed Othman EI Shater, Muhammed Nagy, Mina Gad Seif, Bassam A. Saadany, Amr N. Hafez, Momen Anwar
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Patent number: 8873125Abstract: A Micro Electro-Mechanical System (MEMS) interferometer system utilizes a capacitive sensing circuit to determine the position of a moveable mirror. An electrostatic MEMS actuator is coupled to the moveable mirror to cause a displacement thereof. The capacitive sensing circuit senses the current capacitance of the MEMS actuator and determines the position of the moveable mirror based on the current capacitance of the MEMS actuator.Type: GrantFiled: March 9, 2011Date of Patent: October 28, 2014Assignee: Si-Ware SystemsInventors: Bassam A. Saadany, Amr N. Hafez, Mostafa Medhat, Hisham Haddara
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Publication number: 20140139839Abstract: A Micro-Electro-Mechanical System (MEMS) interferometer provides for self-calibration of mirror positioning of a moveable mirror. The moveable mirror is coupled to a MEMS actuator having a variable capacitance. The MEMS interferometer includes a capacitive sensing circuit for determining the capacitance of the MEMS actuator at two or more known positions of the moveable mirror and a calibration module for using the actuator capacitances at the known positions to compensate for any drift in the capacitive sensing circuit.Type: ApplicationFiled: January 28, 2014Publication date: May 22, 2014Applicant: Si-Ware SystemsInventors: Mostafa Medhat, Bassem Mortada, Ahmed Othman El Shater, Muhammed Nagy, Mina Gad Seif, Bassam A. Saadany, Amr N. Hafez
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Publication number: 20110222067Abstract: A Micro Electro-Mechanical System (MEMS) interferometer system utilizes a capacitive sensing circuit to determine the position of a moveable minor. An electrostatic MEMS actuator is coupled to the moveable minor to cause a displacement thereof. The capacitive sensing circuit senses the current capacitance of the MEMS actuator and determines the position of the moveable minor based on the current capacitance of the MEMS actuator.Type: ApplicationFiled: March 9, 2011Publication date: September 15, 2011Applicant: SI-WARE SYSTEMSInventors: Bassam A. Saadany, Amr N. Hafez, Mostafa Medhat, Hisham Haddara
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Patent number: 6614866Abstract: A PLL-based frequency synthesizer is provided. In accordance with one aspect, a phase locked loop is provided that comprises a phase detector, a loop filter, a voltage controlled oscillator, and a feedback circuit. The phase detector has as inputs a reference frequency signal and a feedback signal. The phase detector is operable to generate a phase detection signal based on a comparison of phases between the reference frequency signal and the feedback signal. The loop filter is coupled to the phase detector for receiving the phase detection signal and generates an output voltage in response to the phase detection signal. The voltage controlled oscillator is coupled to the output voltage of the loop filter and generates a local oscillator signal. The feedback circuit is coupled to the local oscillator signal and generates the feedback signal. The feedback circuit comprises a sampling circuit.Type: GrantFiled: August 16, 2002Date of Patent: September 2, 2003Assignee: Research In Motion LimitedInventors: Amr N. Hafez, Mohamed I. Elmasry
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Publication number: 20020191728Abstract: A PLL-based frequency synthesizer is provided. In accordance with one aspect, a phase locked loop is provided that comprises a phase detector, a loop filter, a voltage controlled oscillator, and a feedback circuit. The phase detector has as inputs a reference frequency signal and a feedback signal. The phase detector is operable to generate a phase detection signal based on a comparison of phases between the reference frequency signal and the feedback signal. The loop filter is coupled to the phase detector for receiving the phase detection signal and generates an output voltage in response to the phase detection signal. The voltage controlled oscillator is coupled to the output voltage of the loop filter and generates a local oscillator signal. The feedback circuit is coupled to the local oscillator signal and generates the feedback signal. The feedback circuit comprises a sampling circuit.Type: ApplicationFiled: August 16, 2002Publication date: December 19, 2002Inventors: Amr N. Hafez, M. I. Elmasry
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Patent number: 6463112Abstract: A PLL-based frequency synthesizer is provided that includes a phase detector, a loop filter, a VCO, a sampler and filter system, and a frequency divider. This architecture reduces the high division ratio (N) necessary in a classical PLL-based frequency synthesizer while maintaining low phase-noise. This is achieved through sub-sampling the VCO output signal in the feedback path. The sampler is placed in the feedback loop following the VCO and is clocked at a low frequency (sub-sampling). The output of the sampler is the beat frequency between the VCO frequency and the sampling clock (in addition to harmonics that are filtered-out by a low-pass filter (LPF)). The LPF in the feedback loop attenuates any tones resulting from the sampling operation. A frequency divider is then used to bring down the feedback signal to the frequency of the phase detector input.Type: GrantFiled: May 25, 2000Date of Patent: October 8, 2002Assignee: Research In Motion LimitedInventors: Amr N. Hafez, Mohamed I. Elmasry
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Patent number: 6262609Abstract: A closed-loop voltage-to-frequency (V/F) converter includes a voltage-controlled-oscillator (VCO) placed in a feedback voltage-locked loop (VLL). This converter achieves both wide bandwidth (for good phase-noise suppression) and good spurious rejection. The closed-loop V/F converter may be further configured in a larger phase-locked loop (PLL) to achieve accurate channel selection that is independent of temperature and process variations.Type: GrantFiled: September 10, 1999Date of Patent: July 17, 2001Assignee: Research In Motion LimitedInventors: Amr N. Hafez, M. I. Elmasry