Sami R Wahab

US Patent:

7769585, Aug 3, 2010

Filed:

Apr 5, 2007

Appl. No.:

11/784216

Inventors:

Sami R. Wahab - Melbourne FL, US

Assignee:

Avidyne Corporation - Lincoln MA

International Classification:

G10L 15/20

US Classification:

704233

Abstract:

An efficient voice activity detection method and system suitable for real-time operation in low SNR (signal-to-noise) environments corrupted by non-Gaussian non-stationary background noise. The method utilizes rank order statistics to generate a binary voice detection output based on deviations between a short-term energy magnitude signal and a short-term noise reference signal. The method does not require voice-free training periods to track the background noise nor is it susceptible to rapid changes in overall noise level making it very robust. In addition a long-term adaptation mechanism is applied to reject harmonic or tonal interference.

US Patent:

20080261638, Oct 23, 2008

Filed:

Apr 23, 2007

Appl. No.:

11/789027

Inventors:

Sami R. Wahab - Melbourne FL, US
Donald Mark Haines - Melbourne FL, US
Constantinos S. Kyriakos - Indian Harbor Beach FL, US
Anthony Nicotra - Melbourne FL, US

International Classification:

H04B 7/00

US Classification:

455500

Abstract:

A direct digital sampling and synthesis general purpose radio system is disclosed which employs single or multiple receiver and/or transmitter sub-systems that require no analog frequency conversion or translation circuitry. Receiver signal processing is disclosed that describes methods of conditioning and digitizing an entire received RF signal band in which the down conversion, channelization and demodulation are performed digitally. In addition, a method for direct synthesis of transmitter signals is also disclosed where up conversion and carrier modulation is performed digitally. Several mitigation techniques are described which aid in overcoming device limitations as well as overcoming problems created by combining multiple digital transmitters and receivers into a single integrated system. One embodiment of the invention describes an integrated VHF/UHF aircraft NAV/COMM radio system which combines a VHF transmitter with four VHF/UHF receivers all of which require no IF circuitry. This embodiment allows for multiple simultaneous airborne radio services on a single platform such as voice and data communication modes (AM, ACARS, VDLM, LAAS, etc.) as well as navigational modes such as VOR, ILS, and Marker Beacon. By utilizing direct digital methods, the signal processing burden is moved almost entirely to the digital domain where the processing can be optimized for each signal type and where linearity is guaranteed. Fewer RF components are required which result in less unit to unit variability, lower production costs, and improved reliability.

US Patent:

6169519, Jan 2, 2001

Filed:

Sep 21, 1999

Appl. No.:

9/399677

Inventors:

Charles L. Holecek - Marion IA
Constantinos S. Kyriakos - Indian Harbour Beach FL
Sami R. Wahab - Melbourne FL

Assignee:

Rockwell Collins, Inc. - Cedar Rapids IA

International Classification:

G01S 504

US Classification:

342442

Abstract:

A TCAS receiver, including a relative bearing measurement radio receiving apparatus for use with an antenna array having four antennas where each antenna has associated with it, its own receiver capable of demodulating both I and Q components of transmissions from an intruding aircraft.

US Patent:

62853139, Sep 4, 2001

Filed:

Sep 21, 1999

Appl. No.:

9/400572

Inventors:

Sami R. Wahab - Melbourne FL
Constantinos S. Kyriakos - Indian Harbour Beach FL
Charles L. Holecek - Marion IA

Assignee:

Rockwell Collins - Cedar Rapids IA

International Classification:

G01S 740

US Classification:

342174

Abstract:

A TCAS receiver/transmitter which uses an improved calibration scheme for improving the ability of the device to transmit in a narrow directional field where the device uses the transmitter frequency source to generate signals for calibration purposes. The calibration uses a technique of simultaneously transmitting from two antennas and manipulating the phase of the signal through successive settings. The signals are monitored by the remaining two antennas and calibration adjustments are made in response thereto.