Abstract: A fiber optic GPS signal device and method comprising a VCSEL multimode transmitter having a gain that, together with the GPS antenna gain, is greater than the VCSEL multimode transmitter noise. When in operative communication, via a long length of multimode fiber, i.e., up to 2000 feet and greater, with a fiber optic receiver, the GPS signals are transmitted at, inter alia, L1 and L2 frequencies with minimal degradation over the length of multimode fiber. The present invention may be used in a variety of GPS transmission applications requiring long lengths of cabling. For example, the invention is particularly useful when the GPS antenna is located on top of an office building or cell phone tower and remotely from the GPS receiver and for use in high-volume commercial telephone synchronizing (DTMF) applications.

Abstract: A fiber optic GPS signal device and method comprising a VCSEL multimode transmitter having a gain that, together with the GPS antenna gain, is greater than the VCSEL multimode transmitter noise. When in operative communication, via a long length of multimode fiber, i.e., up to 2000 feet and greater, with a fiber optic receiver, the GPS signals are transmitted at, inter alia, L1 and L2 frequencies with minimal degradation over the length of multimode fiber. The present invention may be used in a variety of GPS transmission applications requiring long lengths of cabling. For example, the invention is particularly useful when the GPS antenna is located on top of an office building or cell phone tower and remotely from the GPS receiver and for use in high-volume commercial telephone synchronizing (DTMF) applications.

Abstract: A means of accurately determining the position of a selected location such as at the end of a center-pivot irrigation system by using two Global Positioning System (GPS) receivers. The first GPS receiver is located at a fixed, known position such as at the center of the pivoting irrigation system while the second GPS receiver is located on a moving portion of the irrigation system. The first GPS receiver compares the GPS receiver reported position against the actual position and reports by wire or radio link the position differences to the second GPS, where the differences are used to remove errors from the second receiver's measured position.

Abstract: The invention provides for the reception of a L-band signals and MF-band signals using a single antenna element by employing an L-band antenna in conjunction with a connection cable that acts to receive MF-band signals, the invention further providing for the isolation of the L-band signals from an MF-band processing path and isolating the MF-band signals from an L-band processing path.

Abstract: The invention provides for the reception of a L-band signals and MF-band signals using a single antenna element by employing an L-band antenna in conjunction with a connection cable that acts to receive MF-band signals, the invention further providing for the isolation of the L-band signals from an MF-band processing path and isolating the MF-band signals from an L-band processing path.

Abstract: An integrated guidance system for use in swath guidance applications combines the display of swath navigation information with swath guidance system information. A processor receives information from an external positioning system such as a Global Positioning System receiver and generates course correction data derived from swath parameters selected by the user from a displayed menu of options using a control interface that is integrated with the display and processor or is located externally. The swath navigation information is displayed graphically and numerically. The entire apparatus is compact and mountable within the operative view of the user as he operates the equipment to be guided, thereby reducing hazard and navigational error.

Abstract: A method and apparatus for demodulating and decoding an MSK signal utilizing synchronous accumulation and simultaneous synchronization of reference carrier and MSK data clocks enables a GPS correlator channel in a multi-channel GPS receiver to be used for processing MSK signals. The PRN code epochs are synchronized with the MSK data clocks and the process of de-spreading with a PRN code is disabled in order to obtain coherent MSK demodulation without corrupting the MSK signal with a PRN code within the channel.

Abstract: An integrated guidance system for use in swath guidance applications combines the display of swath navigation information with swath guidance system information. A processor receives information from an external positioning system such as a Global Positioning System receiver and generates course correction data derived from swath parameters selected by the user from a displayed menu of options using a control interface that is integrated with the display and processor or is located externally. The swath navigation information is displayed graphically and numerically. The entire apparatus is compact and mountable within the operative view of the user as he operates the equipment to be guided, thereby reducing hazard and navigational error.

Abstract: An apparatus for extending the practical lengths over which coaxial cables can be used to transfer signal information from a Global Positioning System (GPS) antenna to a GPS receiver. The apparatus converts the GPS signal frequency of 1.57542 GHz to a frequency low enough to be transferred long distances over coaxial cables without significant signal attenuation and then converts the signal back to the original frequency without the introduction of frequency errors. The invention is not restricted from being used at other frequencies where system design parameters makes it practical.

Abstract: An electric storage battery is provided having a monitoring device for indicating the state-of-charge of the battery and particularly indicating whether a discharged battery is healthy and capable of being recharged or unhealthy and impending on a state of failure. The monitoring device achieves the foregoing by testing the open circuit voltage of the battery and determining if the voltage of the battery drops below a first preset value after application of a load and subsequently fails to rise above a second preset value after the load has been removed. Also, the monitoring device for the battery includes the capability of sensing when the battery has been placed into a system such as an engine system for an automobile and in response thereto modifying testing certain parameters. Preferably, the monitoring device is made integral with the battery case by providing a receptacle for receiving the device and a pair of connecting arms at least partially embedded in the battery container or cover.

Abstract: A portable laser detection device is disclosed. Optical pulses are sensed by a photodiode and if the pulse width is less than a predetermined value a laser occurred indicator will flash until reset by the user. A laser present indicator will flash and an intermittent audible tone will be generated as long as laser energy having certain characteristics is present. A delay circuit ensures error free detection if a pulse having a width greater than the predetermined value is received immediately after a pulse having a width less than the predetermined value is received. Further, a high energy pulse with a sufficiently fast rise time received by the detector will cause the laser occurred indicator to flash, the laser present indicator to be illuminated continuously, and an audible tone to be generated. The device is shielded against electromagnetic interference and adapts automatically to variations in background noise.

Abstract: Windfinding apparatus is described in which receiver processing of the Global Positioning System (GPS) signals is without knowledge of the spread spectrum codes. The apparatus receiver ignores the bi-phase code and recovers the carrier frequency of all satellites in view of the receiving antenna. Two of these receivers are used in a windfinding system. One of the receivers is located on the ground at a known latitude and longitude. The other receiver is placed on a weather balloon sonde and launched into the atmosphere. A telemetry transmitter aboard the sonde transmits a signal that contains the GPS carrier frequency information to the ground-based telemetry receiver. The telemetry receiver output and the local codeless GPS receiver feed a set of tracking filters. The filtered signals are evaluated to obtain a measurement of the difference between the local GPS receiver carrier frequency and the sonde GPS receiver carrier frequency caused by the velocity of the sonde relative to the ground-based receiver (i.