Abstract: A system and method for controlling locomotives. The system includes a remote control unit (RCU) comprising a processing device and a computer-readable storage medium and a locomotive control unit (LCU) comprising a processing device and a computer-readable storage medium. The LCU is coupled to a locomotive control system of a locomotive for controlling the locomotive and acquiring data therefrom. The LCU is configured for listening to a common radio-frequency channel for a transmission by a network node, waiting for the channel to become free, and transmitting a message after the channel has become free. The RCU is configured for listening to a common radio-frequency channel for a transmission by a network node, waiting for the channel to become free, and transmitting a message after the channel has become free. The system may include one or more repeaters for extending an operational area of the system.

Abstract: A method and system for increased position tracking resolution in a localized environment for use in GPS-denied areas such as within buildings or enclosed structures, comprising: multiple reference nodes each transmitting a synchronization pulse to a multitude of body-worn or device-mounted receiving units; a high speed clock circuit in each receiver capable of measuring the Time Difference of Arrival of said sync pulses to the resolution needed for precise positioning; a central processing computer used to calculate actual position of the receiving units relative to some fixed reference point; and a display system to monitor the position of the receiving units in real time as they move around within the target area overlaid onto available GIS data or building CAD drawings.

Abstract: A system and method for controlling locomotives. The system includes a remote control unit (RCU) comprising a processing device and a computer-readable storage medium and a locomotive control unit (LCU) comprising a processing device and a computer-readable storage medium. The LCU is coupled to a locomotive control system of a locomotive for controlling the locomotive and acquiring data therefrom. The LCU is configured for listening to a common radio-frequency channel for a transmission by a network node, waiting for the channel to become free, and transmitting a message after the channel has become free. The RCU is configured for listening to a common radio-frequency channel for a transmission by a network node, waiting for the channel to become free, and transmitting a message after the channel has become free. The system may include one or more repeaters for extending an operational area of the system.

Abstract: An Emergency Position Indicating Radio Beacon (EPIRB) comprising an integrated wireless receiver, a graphical display device, capability to utilize both internal and external GPS coordinate sources, an infrared background lighting adjustment algorithm, and a multi-LED strobe light array. The receiver provides a return communications path back to the beacon, which is used to acknowledge the receipt of the beacon's outgoing emergency signal by Search and Rescue satellites. The display is used to visually display various operational status information as well as any received messages coming back into the receiver. The GPS receiver system switches between internally derived and/or externally supplied GPS coordinates. The present invention also incorporates an Automatic Background Light Adjustment (ABLA) algorithm to compensate for the maximum range of light intensity encountered by infrared communications LEDs during daytime and nighttime operation.

Abstract: An Emergency Position Indicating Radio Beacon (EPIRB) comprising an integrated wireless receiver, a graphical display device, capability to utilize both internal and external GPS coordinate sources, an infrared background lighting adjustment algorithm, and a multi-LED strobe light array. The receiver provides a return communications path back to the beacon, which is used to acknowledge the receipt of the beacon's outgoing emergency signal by Search and Rescue satellites. The display is used to visually display various operational status information as well as any received messages coming back into the receiver. The GPS receiver system switches between internally derived and/or externally supplied GPS coordinates. The present invention also incorporates an Automatic Background Light Adjustment (ABLA) algorithm to compensate for the maximum range of light intensity encountered by infrared communications LEDs during daytime and nighttime operation.

Abstract: An antenna system comprising a plurality of antennas designed and oriented to provide one or more of radiation pattern, signal polarization and spatial diversity. The various diversity operational characteristics are achieved by using similar antennas physically oriented to provide the diversity attributes or by using dissimilar antennas, that is, antennas having different radiation pattern and/or signal polarization characteristics.

Abstract: An antenna providing circular polarization for received and transmitted signals. The antenna comprises a vertical conductive surfaces oriented to form a closed structure and horizontal conductive surfaces forming a top face of the closed structure. Connection of selected vertical panels to a feed and ground, causes current flow in the vertical and horizontal surfaces that results in a circular polarized signal.

Abstract: There is disclosed a meanderline loaded antenna formed by applying a conductive ink or other conductive material to a flexible substrate. The substrate is then shaped by removing regions and folding other regions along perforated or scored lines to fit the antenna within the available space of a wireless device. In lieu of folding regions of a planar substrate to form a three-dimensional structure, the substrate can be vacuum formed over a mandrel after the antenna elements have been formed thereon. The antenna can also be formed by printing on existing enclosure surfaces of a wireless device or on the surfaces of components within the device. Thus the advantages offered by a meanderline antenna where the effective electrical length is greater than the actual physical length are achieved in conjunction with a space-saving physical structure for the antenna.

Abstract: An antenna providing circular polarization for received and transmitted signals. The antenna comprises a vertical conductive surfaces oriented to form a closed structure and horizontal conductive surfaces forming a top face of the closed structure.

Abstract: An antenna system comprising a plurality of antennas designed and oriented to provide one or more of radiation pattern, signal polarization and spatial diversity. The various diversity operational characteristics are achieved by using similar antennas physically oriented to provide the diversity attributes or by using dissimilar antennas, that is, antennas having different radiation pattern and/or signal polarization characteristics.

Abstract: There is disclosed a meanderline-loaded antenna comprising a ground plane, a non-driven element affixed substantially perpendicular to the ground plane, a driven element affixed substantially perpendicular to the ground plane and a horizontal conductor or radiating element electrically connected between the driven and the non-driven elements and disposed substantially parallel to the ground plane. The non-driven and the driven elements comprise meanderline-loaded couplers that are electrically connected between to the radiating element. A mechanically deformable material is disposed between the radiating element and the ground plane such that in response to an externally generated voltage the mechanically deformable material alters the distance between the ground plane and the radiating element to allow the antenna to adapt to changes in its environment.

Abstract: There is disclosed a meanderline-loaded antenna comprising a ground plane, a non-driven element affixed substantially perpendicular to the ground plane, a driven element affixed substantially perpendicular to the ground plane and a horizontal conductor or radiating element electrically connected between the driven and the non-driven elements and disposed substantially parallel to the ground plane. The non-driven and the driven elements comprise meanderline-loaded couplers that are electrically connected between to the radiating element. A mechanically deformable material is disposed between the radiating element and the ground plane such that in response to an externally generated voltage the mechanically deformable material alters the distance between the ground plane and the radiating element to allow the antenna to adapt to changes in its environment.

Abstract: There is disclosed a meanderline-loaded antenna comprising a ground plane, a non-driven element affixed thereto, a driven or receiving element affixed thereto and a horizontal element between the driven and the non-driven elements. The non-driven and the driven elements comprise meanderline-loaded couplers that are oriented parallel to the ground plane and the horizontal element so as to present a low-profile meanderline-loaded antenna.

Abstract: There is disclosed a meanderline loaded antenna formed by applying a conductive ink or other conductive material to a flexible substrate. The substrate is then shaped by removing regions and folding other regions along perforated or scored lines to fit the antenna within the available space of a wireless device. In lieu of folding regions of a planar substrate to form a three-dimensional structure, the substrate can be vacuum formed over a mandrel after the antenna elements have been formed thereon. The antenna can also be formed by printing on existing enclosure surfaces of a wireless device or on the surfaces of components within the device. Thus the advantages offered by a meanderline antenna where the effective electrical length is greater than the actual physical length are achieved in conjunction with a space-saving physical structure for the antenna.

Abstract: An integrated antenna and filter. Integrating and collocating the antenna element and a signal filter eliminates the affects of interfering signals that are induced in the transmission line between the antenna and the receiver/transmitter. The use of fiber optic transmission line cable for connecting the receiver/transmitter and the antenna reduces spurious radio frequency emissions from the transmission line that can cause interference to other nearby receiver/transmitter systems and prevents spurious interfering signals from entering the transmission line.

Abstract: There is disclosed a meanderline loaded antenna comprising a ground plane, a plurality of vertical elements orthogonally affixed thereto, a driven vertical element affixed thereto and a horizontal element between the vertical elements. All but one of the plurality of vertical elements have an effective electrical length that is a quarter wavelength of the antenna operating frequency. Thus, these vertical elements represent an open and do not effect the antenna performance characteristics. One of the plurality of vertical elements will be operative and therefore the antenna length comprises the length of the operative element, the length of the driven element, and the length of the top plate therebetween.

Abstract: There is disclosed a meanderline-loaded antenna comprising a ground plane, a non-driven element affixed thereto, a driven or receiving element affixed thereto and a horizontal element between the driven and the non-driven elements. The non-driven and the driven elements comprise meanderline-loaded couplers that are oriented parallel to the ground plane and the horizontal element so as to present a low-profile meanderline-loaded antenna.