David W Matolak

US Patent:

6810028, Oct 26, 2004

Filed:

Sep 6, 2000

Appl. No.:

09/656099

Inventors:

Thomas R. Giallorenzi - Herriman UT
David W Matolak - Athens OH
Douglas G. Bowen - Spanish Fork UT

Assignee:

L-3 Communications Corp. - New York NY

International Classification:

H04B 7212

US Classification:

370324, 370320, 370350, 375358, 455 132

Abstract:

Method and apparatus for maintaining synchronization in a CDMA communication system by operating closed loop timing control between a radio base unit and subscriber units, operating open loop timing control between the radio base unit and the subscriber units, and using timing information derived from the open loop to correct the closed loop. Generally the open loop is faster in response than the closed loop. The open loop timing control may be generated by using GPS data. A radio base station and a subscriber unit operating in accordance with these principles.

US Patent:

7672453, Mar 2, 2010

Filed:

Aug 21, 2000

Appl. No.:

09/642373

Inventors:

David William Matolak - Athens OH, US

Assignee:

Lockheed Martin Corporation - Bethesda MD

International Classification:

H04K 1/02
H04L 9/06

US Classification:

380 35, 380263, 380265

Abstract:

A communication system includes an encryptor and a decryptor. For improved encryption security, the encryptor includes a multitap delay line to produce mutually delayed samples of the signal to be encrypted. Each sample is operated on by a key or function to produce modified signal samples, and the modified signal samples are summed or combined to produce the encrypted signal. According to one aspect of the invention, at least one of the keys or functions includes a nonlinear function. In some embodiments, the functions are time-variant for improved security. Decryption is accomplished in some embodiments by an equalizer. The preferred equalizer is the maximum-likelihood-sequence estimators matched to the encryption functions. A Viterbi algorithm makes it easy to implement the matched equalizer.

US Patent:

7881361, Feb 1, 2011

Filed:

Oct 31, 2005

Appl. No.:

11/665697

Inventors:

David W. Matolak - Athens OH, US

Assignee:

Ohio University - Athens OH

International Classification:

H04B 1/707

US Classification:

375141, 375146, 375147

Abstract:

A system () for communicating a direct sequence spread spectrum signal, a related transmitter (), a related receiver (), and methods associated therewith are provided in various embodiments. A data rate vector, a processing gain vector, a frequency separation vector, and a bit energy vector may be associated with transmitting and/or receiving a direct sequence spread spectrum signal. Each vector has a value associated with each of a plurality of channels associated with subcarriers in the direct sequence spread spectrum signal. A value for at least one of the data rate vector, processing gain vector, frequency separation vector, and bit energy vector for at least one channel is different from another value for the corresponding data rate vector, processing gain vector, frequency separation vector, or bit energy vector for another channel. Having one or more vectors with different values provides a spectrally-shaped generalized multitone (or multicarrier) direct sequence spread spectrum (SSG-MT-DS-SS) modulation scheme.

US Patent:

56510284, Jul 22, 1997

Filed:

May 9, 1995

Appl. No.:

8/437752

Inventors:

Johnny Michael Harris - Centerville UT
Thomas Robert Giallorenzi - Salt Lake City UT
David William Matolak - Salt Lake City UT
Dan Michael Griffin - Bountiful UT

Assignee:

Unisys Corporation - Blue Bell PA

International Classification:

H04L 2549
H04L 2534
H04B 1500

US Classification:

375286

Abstract:

An electronic data transmission system has a low peak-to-average power ratio by including a transmitter circuit which receives an input signal and in response generates a distorted output signal. This distorted output signal is generated such the output signal has a large magnitude when the input signal has a high probability of occurrence, and the output signal has a small magnitude when the input signal has a low probability of occurrence. The distorted output signal travels over a communication channel to a receiver circuit which regenerates the input signal by amplifying the distorted output signal with a gain that is the inverse of the gain by which the distorted signal is generated.

US Patent:

57937974, Aug 11, 1998

Filed:

May 9, 1995

Appl. No.:

8/437764

Inventors:

Thomas Robert Giallorenzi - Salt Lake City UT
David William Matolak - Salt Lake City UT
Johnny Michael Harris - Centerville UT
Robert William Steagall - North Salt Lake UT
Bruce Howard Williams - Sandy UT

Assignee:

Unisys Corporation - Blue Bell PA

International Classification:

H04B 1500
H04K 100
H04L 2730

US Classification:

375206

Abstract:

An electronic data transmission system has a low peak-to-average power ratio by including a transmitter circuit which receives an input signal and in response generates a distorted output signal. This distorted output signal is generated by amplifying the input signal with one particular gain when the input signal is at a maximum magnitude which gives the distorted output signal a corresponding maximum magnitude, and by amplifying the input signal with a larger gain when the input signal is in a predetermined range below the maximum magnitude. The distorted output signal travels over a communication channel to a receiver circuit, which regenerates the input signal by amplifying the distorted output signal with a gain that is the inverse of the gain by which the distorted signal is generated.

US Patent:

58258353, Oct 20, 1998

Filed:

Feb 23, 1996

Appl. No.:

8/606285

Inventors:

Samuel C. Kingston - Salt Lake UT
Thomas R. Giallorenzi - Salt Lake UT
Robert William Steagall - North Salt Lake UT
David Matolak - Herndon VA

Assignee:

L-3 Communications Corporation - New York NY

International Classification:

H04L 700

US Classification:

375367

Abstract:

Disclosed are methods and apparatus for use in a synchronous CDMA communications system (10) that employs orthogonal pn spreading codes. The methods are intended for synchronizing transmissions from a subscriber unit (SU 14) to a radio base unit (RBU 12), and include the steps of: (a) transmitting individual ones of a plurality of bursts from the SU to the RBU, each burst being transmitted with a different pn spreading code timing alignment; (b) receiving individual ones of the plurality of bursts with the RBU and determining a power estimate of each received burst; and (c) in response to a determined power estimate of one of the bursts exceeding a threshold, sending a message from the RBU to the SU. The message indicates that the SU is to use for subsequent transmissions the pn spreading code timing alignment that was employed when transmitting the burst that exceeded the threshold. In a preferred embodiment of this invention the step of transmitting transmits an indication of the pn spreading code timing alignment used when transmitting a given one of the bursts.

US Patent:

59035510, May 11, 1999

Filed:

Jan 12, 1998

Appl. No.:

9/005938

Inventors:

Samuel C Kingston - Salt Lake City UT
Thomas R. Giallorenzi - Salt Lake City UT
Randal R Sylvester - West Valley City UT
David W Matolak - Salt Lake City UT
Patrick J Smith - Salt Lake City UT

Assignee:

L-3 Communications Corporation - New York NY

International Classification:

H04B7/216

US Classification:

370335

Abstract:

Disclosed are methods for acquiring a forward channel in a point-to-multipoint CDMA system. One method includes the steps of (a) despreading a received CDMA signal with a first pn code that is known to be present in the received CDMA signal and obtaining a first measure of received signal level; (b) despreading the received CDMA signal with a second pn code that is known not to be present in the received CDMA signal and obtaining a second measure of received signal level; and (c) synchronizing to a desired channel using a difference between the first and second signal levels. In this method the first step of despreading despreads a continuously transmitted side-channel, and the step of synchronizing synchronizes to the side-channel. Also, the step of obtaining a first measure of received signal level obtains a correlation peak, and the step of obtaining a second measure of received signal level obtains a correlation null. Preferably, the steps of despreading and obtaining are accomplished iteratively over a range of n first pn code phase states and over a range of n second pn code phase states.

US Patent:

58055843, Sep 8, 1998

Filed:

Feb 23, 1996

Appl. No.:

8/606378

Inventors:

Samuel C. Kingston - Salt Lake City UT
Thomas R. Giallorenzi - Salt Lake City UT
Randal R. Sylvester - West Valley City UT
David W. Matolak - Herndon VA
Patrick J. Smith - Salt Lake City UT

Assignee:

L-3 Communications Corporation - New York NY

International Classification:

H04B 7216
H04J 306

US Classification:

370342

Abstract:

Disclosed are methods for acquiring a forward channel in a point-to-multipoint CDMA system. One method includes the steps of (a) despreading a received CDMA signal with a first pn code that is known to be present in the received CDMA signal and obtaining a first measure of received signal level; (b) despreading the received CDMA signal with a second pn code that is known not to be present in the received CDMA signal and obtaining a second measure of received signal level; and (c) synchronizing to a desired channel using a difference between the first and second signal levels. In this method the first step of despreading despreads a continuously transmitted side-channel, and the step of synchronizing synchronizes to the side-channel. Also, the step of obtaining a first measure of received signal level obtains a correlation peak, and the step of obtaining a second measure of received signal level obtains a correlation null. Preferably, the steps of despreading and obtaining are accomplished iteratively over a range of n first pn code phase states and over a range of n second pn code phase states.