Carl Anthony Willis

US Patent:

7225258, May 29, 2007

Filed:

Sep 9, 2002

Appl. No.:

10/238171

Inventors:

Edward K. Orcutt - Cave Creek AZ, US
Randall K. Bahr - Scottsdale AZ, US
Carl M. Willis - Mesa AZ, US

Assignee:

General Dynamics Corporation - Scottsdale AZ

International Classification:

G06F 15/173

US Classification:

709226, 709223, 709238, 709242

Abstract:

The present invention provides a network connectivity system and method that facilitate the design of a network connectivity plan where the availability of link resources is limited and varies with the time. The preferred system and methods can be used to provide a network connection plan that fully connects such a network, where possible, while efficiently allocating the link resources used to implement the network connection plan. The network connectivity system and method develops the network connection plan by choosing links based on link resource availability and link duration. Thus, the network connectivity system and method creates a connection plan that, if possible, keeps full connectivity in the network, compensating for changes over time in the availability of links. The network connectivity system thus provides the ability to efficiently connect dynamic networks in a way that facilitates the routing of data to between nodes in the communication network.

US Patent:

56466269, Jul 8, 1997

Filed:

Jan 30, 1996

Appl. No.:

8/593103

Inventors:

Carl M. Willis - Mesa AZ

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

G01S 728

US Classification:

342189

Abstract:

A pseudorandom noise coded system (100) compensates for imperfections, improving out of range rejection, and includes a digital correlator (200) having a first complex multiplier (202) receiving a sequence of sampled data words and a sequence of precomputed complex data words and producing a sequence of first complex product words. A second complex multiplier (204) receives the sequence of first complex product words and a precomputed constant word and produces a sequence of second complex product words. A complex multiplexer (206) receives a sequence of binary code states, and the sequences of first and second complex product words and produces a sequence of complex multiplexer output words formed as a replica of either the first or the second complex product words, depending on the binary code. A complex accumulator (208) receives the sequence of complex multiplexer output words and produces a complex accumulated sum word formed as a complex sum of the complex multiplexer output words.

US Patent:

56466277, Jul 8, 1997

Filed:

Jan 30, 1996

Appl. No.:

8/593962

Inventors:

Carl Myron Willis - Mesa AZ
Thomas Frederick Koehler - Scottsdale AZ

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

G01S 728

US Classification:

342189

Abstract:

This invention relates to a method and apparatus for controlling a biphase modulator (602, 702) to improve autocorrelation in pseudorandom noise coded systems. The biphase modulator modulates a carrier frequency with one of two phase states responsive to a pseudorandom noise (PN) binary code sequence. The spectrum (610, 710) at the output of the biphase modulator comprises a plurality of spectral lines separated by the code repetition frequency, including a center spectral line (611, 711) and at least one adjacent spectral line (612-615, 712-717). The magnitude of the center spectral line is measured and compared to a reference to produce a control signal which is responsive to the magnitude of the center spectral line. This control signal is supplied to the biphase modulator for maintaining a predetermined magnitude of the center spectral line thereby achieving a desired spectrum output and improving autocorrelation of the system.

US Patent:

59302925, Jul 27, 1999

Filed:

Apr 21, 1997

Appl. No.:

8/845225

Inventors:

Carl Myron Willis - Mesa AZ

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

H04B 1500
H04K 100
H04L 2730

US Classification:

375208

Abstract:

The present invention describes a method and apparatus for improving the autocorrelation performance in spread spectrum radar and communications systems by using a tri-state digital correlator to demodulate the received biphase modulated waveform. The tri-state correlator (100) includes a multiplexer (112) having a code input for receiving a tri-state code sequence, and three inputs each for receiving a sequence of data words including a first input for receiving a digitized signal data word, a second input for receiving an inverted digitized signal data word, and a third input for receiving a zero data word. The multiplexer includes an output and a means for producing a sequence of data words at the output, said means presenting at the output exactly one of the three data words appearing at either the first, second, or third input depending on which of the three code states appears at the code input. The present invention also describes the manner in which the tri-state code sequence is constructed from a binary code sequence to effect a significant improvement in the autocorrelation performance.

US Patent:

54971608, Mar 5, 1996

Filed:

Sep 17, 1993

Appl. No.:

8/123508

Inventors:

Thomas F. Koehler - Scottsdale AZ
Carl M. Willis - Mesa AZ

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

G01S 1312
G01S 1328
G01S 1340

US Classification:

342145

Abstract:

A method and apparatus is disclosed for improved out-of-range rejection in pseudo-random noise (PN) coded systems by adjusting the relative phase difference between the two phase states of a bi-phase modulation. The energy in the spectral lines of the bi-phase modulated RF signal to generate a signal to be fedback to a voltage-controlled bi-phase modulator to adjust the relative phase difference between the two phase states. Sampled signals are mixed down to baseband using single sideband suppressed carrier modulation of the center frequency of the transmitted signal and the offset frequency. The offset frequency is chosen to be less than the PN code repetition frequency. The baseband signal is filtered and envelop detected producing a DC voltage proportional to the amplitude of the center line of the PN spectrum which is compared to either a fixed reference or to the amplitude of one or more of the remaining lines in the spectrum. The comparison provides an error signal adjusting the phase of the bi-phase modulator providing improved out-of-range rejection.