David H Halvorson

US Patent:

6360998, Mar 26, 2002

Filed:

Jun 9, 1998

Appl. No.:

09/094174

Inventors:

David H. Halvorson - Cedar Rapids IA
Joe B. Hungate - Marion IA
Stephen R. Montgomery - Marion IA

Assignee:

Westinghouse Air Brake Company - Wilmerding PA

International Classification:

B61L 2334

US Classification:

246122R

Abstract:

An apparatus for determining the presence of a third rail disposed between parallel railroad tracks as a train progresses along said parallel railroad tracks and further for determining the relative direction of motion of said third rail with respect to said first two rails and further for determining the rate at which the third rail moves with respect to the first rails is disclosed, which is a low power radar sensor disposed underneath the rail vehicle and directed toward the rail on the opposing side of the vehicle. In a preferred embodiment, two rail detectors are shown which are disposed on opposite sides of the rail vehicle. The radar detectors are coupled with an onboard computing device and with other components of an advanced train control system which can be used for precisely locating the train on closely spaced parallel tracks and further for updating and augmenting position information used by the advanced train control system. The system including GPS receivers and wheel tachometers for providing alternate sources of information for position determination.

US Patent:

6377215, Apr 23, 2002

Filed:

Jun 9, 1998

Appl. No.:

09/094297

Inventors:

David H. Halvorson - Cedar Rapids IA
Joe B. Hungate - Marion IA

Assignee:

WABTEC Railway Electronics - Germantown MD

International Classification:

G01S 302

US Classification:

342458, 105168, 1051901, 246124, 701 19

Abstract:

An apparatus for determining the rotation of a wheel truck on a rail vehicle and further for determining the relative direction of motion of said truck with respect to said rail vehicle and further for determining the rate at which the truck moves with respect to the rail vehicle is disclosed, which is a low power radar sensor disposed underneath the rail vehicle and directed toward the truck. In a Preferred embodiment, two sensors are shown which are disposed on opposite sides of the rail vehicle. The sensors are coupled with an onboard computing device and with other components of a train control system which can be used for precisely locating the train on closely spaced parallel tracks and further for updating and augmenting position information used by the train control system. The system including GPS receivers and wheel tachometers for providing alternate sources of information for position determination.

US Patent:

7639998, Dec 29, 2009

Filed:

Feb 7, 2007

Appl. No.:

11/703351

Inventors:

David H. Halvorson - Cedar Rapids IA, US

Assignee:

Rockwell Collins, Inc. - Cedar Rapids IA

International Classification:

H04B 1/16

US Classification:

4552511, 4552342, 4553431

Abstract:

A radio frequency (RF) receiver utilizing dynamic power management for administration of power consumption. The RF receiver includes an RF antenna, an RF full band filter, an RF amplifier, an RF sub-band filter, a first local oscillator, an RF mixer, a first IF amplifier, an IF wide band filter, a second local oscillator, an IF mixer, two secondary IF amplifiers, an IF narrow band filter, a digital signal processing subsystem, three power sensors, and a control logic subsystem. Based on its location in the system, each power sensor has a unique threshold setting that is set just below a total RF power level where desired signal degradation might occur. The control logic subsystem utilizes outputs of the power sensors to detect a total RF power present due to interfering signals plus a desired signal within an entire bandwidth present at each stage and dynamically manages power by adjusting bias of each stage accordingly via its bias control outputs.

US Patent:

62088599, Mar 27, 2001

Filed:

Feb 26, 1998

Appl. No.:

9/030953

Inventors:

David H. Halvorson - Cedar Rapids IA

Assignee:

Motient Services Inc. - Reston VA

International Classification:

H04Q7/20

US Classification:

455430

Abstract:

In a communication system, such as a satellite communication system, a method of performing a priority process for a priority event includes the steps of continuously monitoring, by a mobile communication system (MCS), for receipt of a priority message, transmitting, by a controller, a first message including the priority message in the communication system, and receiving the first message by the MCS. The method also includes the steps of receiving, by the MCS, a second message to be transmitted to the communication system, and performing, by the MCS, a message segment protocol to the second message creating message segments. The method also includes the steps of transmitting, by the at least one MCS, each message segment until all of the message segments have been transmitted, and receiving, by the controller, the message segments, until all of the message segments have been received.

US Patent:

62082469, Mar 27, 2001

Filed:

Jul 31, 1998

Appl. No.:

9/127410

Inventors:

Jeffrey D. Kernwein - Cedar Rapids IA
David H. Halvorson - Cedar Rapids IA

Assignee:

Wabtec Railway Electronics, Inc. - Germantown MD

International Classification:

B60Q1/26

US Classification:

340468

Abstract:

A method and apparatus for providing warning lamps on the side of railcars where the lamps are powered by and receive information from a power line extending across numerous cars of the train and where the power line also provides power and information to the electronic air brakes disposed on the various railcars.

US Patent:

59865792, Nov 16, 1999

Filed:

Jul 31, 1998

Appl. No.:

9/127408

Inventors:

David H. Halvorson - Cedar Rapids IA

Assignee:

Westinghouse Air Brake Company - Germantown MD

International Classification:

G08G 101
B61L 300

US Classification:

340933

Abstract:

A method and apparatus for determining railcar order in an ECP equipped train involving the inherent propagation delay of a pneumatic signal propagation in a brake air line as measured by each car and used to determine the car order in the train.

US Patent:

61277479, Oct 3, 2000

Filed:

Sep 16, 1999

Appl. No.:

9/397112

Inventors:

David H. Halvorson - Cedar Rapids IA

Assignee:

Westinghouse Air Brake Technologies Corporation - Wilmerding PA

International Classification:

H01H 3500

US Classification:

307131

Abstract:

A method and apparatus detects leakage current on a two wire power line and, in particular, provides a way to prevent hazardous electrical shocks to personnel on ECP equipped railroad trains. Two resistors of equal value are respectively connected in series to the two wires of the power line. A sensing resistor is connected in series with a junction of first two resistors, and a low voltage power source is connected between the sensing resistor and earth ground. A sensor is connected across the sensing resistor to detect a leakage current. The sensor is capable of detecting either positive or negative leakage currents. An output of the sensor is supplied to a controller which controls a high voltage power source connected across the two wires of the power line to be either in an OFF state or enabled to be in an ON state, depending on whether a leakage current is sensed by the sensor.

US Patent:

61149748, Sep 5, 2000

Filed:

Aug 25, 1999

Appl. No.:

9/382682

Inventors:

David H. Halvorson - Cedar Rapids IA

Assignee:

WABTEC Railway Electronics - Germantown MD

International Classification:

G08G 101
B61L 300

US Classification:

340933

Abstract:

A method and apparatus for determining railcar order in an ECP equipped train involving the inherent propagation delay of a pneumatic signal propagation in a brake air line as measured by each car and used to determine the car order in the train.