Abstract: An apparatus for identifying failed or suspect RF transmitting devices while the devices are in normal operation transmitting over-the-air RF signals. The apparatus comprises an RF signal sensor receiving the RF signals from at least one of the devices that are mobile or portable. The sensor is responsive to the received RF signals. An analyzer determines RF frequency characteristics of the received RF signals from the at least one transmitting device, determines the respective identifier of the at least one transmitting device from the received RF signals, and uses the identifier from the received RF signals to correlate the RF frequency characteristics of the particular one of the transmitting devices. A graphical user interface displays at least one RF frequency characteristic in a form that can be used to identify transmitting devices that have failed and transmitting devices that are suspect.

Abstract: Disclosed is a system for hierarchical-based tracking and information exchange. A location server administrator controls a hierarchy. The system includes a plurality of mobile devices. Each mobile device runs a tracking application and/or information exchange application. A location server that uses a processor to: push and/or pull tracking information controlled by the hierarchy; push and/or pull other forms of information exchange between devices and controlled by the hierarchy; control a dissemination of information between devices running the tracking application and/or information exchange application based on the hierarchy; and control the dissemination of information between devices running the tracking application and/or information exchange application based on location.

Abstract: An apparatus for determining operating characteristics of radio-frequency (RF) transmitting devices while the devices are in normal operation transmitting over-the-air RF signals. The apparatus comprises at least one signal sensor for receiving the RF signals, each sensor responsive to the RF signals received at a plurality of antennas or received at a directional antenna, an analyzer for determining signal parameters of received RF signals and for determining operating characteristics of the transmitting devices from the signal parameters, wherein each RF signal includes an identifier of the transmitting device, the apparatus using the identifier to link operating characteristics determined from the RF signals to the transmitting device, and a graphical user interface for displaying the operating characteristics for each transmitting device.

Abstract: An apparatus for determining a health of radio-frequency transmitters each transmitting a transmitted signal during normal operation. The apparatus comprises a receiver for receiving received signals, each received signal responsive to a transmitted signal, a first element for determining signal parameters of each received signal, the signal parameters responsive to an operating condition of a transmitter, each transmitted signal and each associated received signal including an identifier of the transmitter that transmitted the transmitted signal, the apparatus using the identifier to link determined signal parameters with the transmitter that transmitted the transmitted signal and a second element for determining a health of the transmitter that transmitted the transmitted signal, the health responsive to a relationship between one or more signal parameters and a selected value or a range of selected values for each signal parameter.

Abstract: An apparatus for determining operating characteristics of radio-frequency (RF) transmitting devices while the devices are in normal operation transmitting over-the-air RF signals. The apparatus comprises at least one signal sensor for receiving the RF signals, each sensor responsive to the RF signals received at a plurality of antennas or received at a directional antenna, an analyzer for determining signal parameters of received RF signals and for determining operating characteristics of the transmitting devices from the signal parameters, wherein each RF signal includes an identifier of the transmitting device, the apparatus using the identifier to link operating characteristics determined from the RF signals to the transmitting device, and a graphical user interface for displaying the operating characteristics for each transmitting device.

Abstract: An apparatus for determining a health of radio-frequency transmitters each transmitting a transmitted signal during normal operation. The apparatus comprises a receiver for receiving received signals, each received signal responsive to a transmitted signal, a first element for determining signal parameters of each received signal, the signal parameters responsive to an operating condition of a transmitter, each transmitted signal and each associated received signal including an identifier of the transmitter that transmitted the transmitted signal, the apparatus using the identifier to link determined signal parameters with the transmitter that transmitted the transmitted signal and a second element for determining a health of the transmitter that transmitted the transmitted signal, the health responsive to a relationship between one or more signal parameters and a selected value or a range of selected values for each signal parameter.

Abstract: An apparatus for determining operating characteristics of radio-frequency (RF) transmitting devices while the devices are in normal operation transmitting over-the-air RF signals. The apparatus comprises at least one signal sensor for receiving the RF signals, each sensor responsive to the RF signals received at a plurality of antennas or received at a directional antenna, an analyzer for determining signal parameters of received RF signals and for determining operating characteristics of the transmitting devices from the signal parameters, wherein each RF signal includes an identifier of the transmitting device, the apparatus using the identifier to link operating characteristics determined from the RF signals to the transmitting device, and a graphical user interface for displaying the operating characteristics for each transmitting device.

Abstract: An apparatus for determining a health of radio-frequency transmitters each transmitting a transmitted signal during normal operation. The apparatus comprises a receiver for receiving received signals, each received signal responsive to a transmitted signal, a first element for determining signal parameters of each received signal, the signal parameters responsive to an operating condition of a transmitter, each transmitted signal and each associated received signal including an identifier of the transmitter that transmitted the transmitted signal, the apparatus using the identifier to link determined signal parameters with the transmitter that transmitted the transmitted signal and a second element for determining a health of the transmitter that transmitted the transmitted signal, the health responsive to a relationship between one or more signal parameters and a selected value or a range of selected values for each signal parameter.

Abstract: An apparatus for determining operating characteristics of radio-frequency (RF) transmitting devices while the devices are in normal operation transmitting over-the-air RF signals. The apparatus comprises at least one signal sensor for receiving the RF signals, each sensor responsive to the RF signals received at a plurality of antennas or received at a directional antenna, an analyzer for determining signal parameters of received RF signals and for determining operating characteristics of the transmitting devices from the signal parameters, wherein each RF signal includes an identifier of the transmitting device, the apparatus using the identifier to link operating characteristics determined from the RF signals to the transmitting device, and a graphical user interface for displaying the operating characteristics for each transmitting device.

Abstract: A method for testing each one of a plurality of receiving sites operative in a time difference of arrival geo-location system. The method comprises determining a theoretical time of arrival of a test message at each receiving site assuming the test message was transmitted from a test message transmitting antenna at a known location; determining a measured time of arrival of the test message at each receiving site, the test message transmitted from the test message transmitting antenna; determining a true time of arrival of the test message at each receiving site, the true time of arrival comprising the measured time of arrival less a start time of the test message; determining a difference between the theoretical and the true times of arrival for each receiving site, wherein the difference for each receiving site is indicative of a health of the receiving site.