751results about "Direction finders using radio waves" patented technology

A geographic based communications service system that includes a network and a plurality of access points connected to the network and arranged at known locations in a geographic region. One or more service providers or information providers may be connected to the network to provide services or information on the network. A mobile user (MU) may use a portable computing device (PCD) to connect to the network and access information or services from the network. The PCD may be configured to transmit a signal indicating a presence of the PCD as well as identification information indicating the mobile user. Upon detection of the wireless signal by a first access point in proximity to the PCD, and upon receipt of the identification information indicating the user of the PCD, the first access point may transmit the identification information, as well as the known geographic location of the first access point, to one or more providers on the network. The known geographic location of the first access point indicates the approximate location of the PCD of the mobile user. A first information provider may receive this information and provide content information or services to the mobile user. For example, the first information provider may select content information dependent upon the known geographic location of the first access point and demographic information or past activities of the mobile user of the PCD. The first information provider may then provide the selected content information through the network and through the first access point to the PCD of the mobile user.

A system that tracks the current and historical locations of a GPS locator device carried by a person provides widely available access to data referencing these locations, so that a parent can easily and frequently monitor the location of a child. Monitoring of a child's location may be conducted via a Web site, which provides graphical maps of location data, or via calling into a call center. The present invention also provides a means for a parent to trigger the automatic transmission of the device's location, via a Web site or call placed to a call center agent or a VRU. The present invention also provides a process of auto-notification of a device's movement that exceeds a pre-specified threshold. The present invention also includes a capability to function as a proximity alert device.

A system and method for estimating the position of wireless devices within a wireless communication network combines measured RF channel characteristics for the wireless device with one or more predicted performance lookup tables, each of which correlates an RF channel characteristic to some higher order network performance metric and/or a position within an environmental model. Measured RF channel characteristics for wireless devices are compared against the performance lookup tables to determine the sent of lookup tables that most closely match the measured RF channel characteristics. The positions within the environmental model corresponding to the selected set of matching lookup tables are identified as possible locations for the wireless device. The performance lookup tables are uniquely constructed by site-specific location, technology, wireless standard, and equipment types, and/or the current operating state of the communications network.

Arrangement for monitoring an asset including an interior sensor system arranged on the asset to obtain information about contents in the interior of the asset, a location determining system arranged on the asset to monitor the location of the asset and a communication system arranged on the asset and coupled to the interior sensor system and the location determining system. The communication system operatively transmits the information about the contents in the interior of the asset and the location of the asset to a remote facility. The interior sensor system may include at least one wave transmitter arranged to transmit waves into the interior of the asset and at least one wave receiver arranged to receive waves from the interior of the asset. A processor may be provided to compare waves received by the wave receiver(s) at different times or analyze the waves received by the wave receiver(s).

An ultra wideband (UWB) or short-pulse transmission system that enables precise tracking or geolocation of a target over distances of several kilometers. The system includes a set of N (where N>2) untethered UWB transceivers located at fixed positions, an untethered UWB receiver at the target, and a processor at the target for resolving time-of-flight measurement ambiguities of received pulses to determine precise geolocation by solving a set of equations according to time-of-flight measurements and surveyed positions of N-1 transceivers. To eliminate a clock distribution system, self-synchronizing of pulse timing is achieved by generating a start pulse at one of the untethered transceivers. Alternatively, a timing source may be provided by a GPS or other timing generator at the transceivers in order to synchronize emissions of their pulses.

Techniques to estimate the position of a wireless terminal. In a method, the identities of a number of transmitters (e.g., BTSs) to be used to estimate the position are initially received. Expected areas for these transmitters are then determined. The expected area associated with each transmitter is indicative of an area where the terminal is likely to be located given that the signal from the transmitter is received by the terminal. Each expected area may comprise a location (e.g., the expected area center) to be used as an estimated position of the terminal and an uncertainty (or error estimate) associated with that estimated position. The expected areas for the transmitters are then combined (e.g., based on a weighted average) to determine a combined expected area, which is then provided as the estimate of the position of the terminal.

The navigation system method described herein could guide people around urban environments, detect guide and navigate them to destinations, add-on to the portable phone. We have focused on the task of detecting and navigating even in situations in which Global Positioning Systems (GPS) cannot provide this information, such as when the person is indoors or in crowded urban areas where there is no line of site to the GPS satellites. The information will be received directly from RF sensors and will display on the existing cellular phone as Bluetooth application

A system for wirelessly locating mobile station/units (MS) and using resulting location determinations for providing a product or service is disclosed. The system is useful for routing an MS user to a plurality of desired locations, alerting an MS user to a nearby desired product or service based on satisfaction of user criteria, and providing enhanced security and 911 response. In one embodiment, the system responds to MS location requests via, e.g., Internet communication between a distributed network of location processing sites. A plurality of locating technologies including those based on: (1) TDOA; (2) pattern recognition; (3) timing advance; (5) GPS and network assisted GPS, (6) angle of arrival, (7) super resolution enhancements, and (8) supplemental information from low cost base stations can be activated, in various combinations, by system embodiments. MS location difficulties resulting from poor location accuracy/reliability and/or poor coverage are alleviated via such technologies in combination with automatically adapting and calibrating system performance according to environmental and geographical changes so that the system becomes progressively more comprehensive and accurate. Further, the system can be modularly configured for use in location signaling environments ranging from urban, dense urban, suburban, rural, mountain to low traffic or isolated roadways. Accordingly, the system is useful for 911 emergency calls, tracking, routing, people and animal location including applications for confinement to and exclusion from certain areas.

An interruption-free hand-held positioning method and system, carried by a person, includes an inertial measurement unit, a north finder, a velocity producer, a positioning assistant, a navigation processor, a wireless communication device, and a display device and map database. Output signals of the inertial measurement unit, the velocity producer, the positioning assistant, and the north finder are processed to obtain highly accurate position measurements of the person. The user's position information can be exchanged with other users through the wireless communication device, and the location and surrounding information can be displayed on the display device by accessing a map database with the person position information.

A child locating and tracking apparatus which provides for the location of a child that is lost, abducted or in general danger to be quickly located is disclosed. The apparatus uses a small transmitter that is always carried by the child and as such, is always present when danger arises. The transmitter is easily disguised and hidden in the child's clothing or personal adornments such as shoes, coats, watches, earrings, bracelets, rings and the like. The apparatus uses a system of world wide receivers such as those provided by local cellular telephone towers or by low earth orbiting satellites used for low power communication. When a child is lost or in danger, the child simply activates the transmitter which sends a signal to a central reporting station or stations where trained personnel will contact the respective parents and/or care givers to determine if the child could possibly be in danger. If an affirmative decision is reached, the monitoring station personnel will then assist the local law enforcement officials in the respective area anywhere in the world where the alarm was received in locating the child and removing the child from harm's path.

Techniques to more accurately measure the arrival times of transmissions received at a remote terminal from a number of base stations. In one aspect, unassigned finger processors are used to process and measure the arrival times of transmissions from base stations not in the active set. In another aspect, if no finger processors are available for assignment, the arrival times can be measured in the time period between updates of a reference oscillator used for the measurements. In accordance with a method for determining a position of a remote terminal, a first set of one or more base stations in active communication with the remote terminal is identified and each base station in the first set is assigned at least one finger processor. A second set of one or more base stations not in active communication with the remote terminal is also identified and an available finger processor is assigned to each of at least one base station in the second set. A (signal arrival) time measurement is then performed for each base station, and outputs indicative of the measurements are provided for further processing. To improve accuracy, the measurements can be performed within a narrow time window.

Embodiments of the present invention are directed at gathering position information of mobile and stationary entities and using the position information in a wide variety of applications. Various embodiments use a plurality of signal transmitting devices and/or a plurality of signal gathering devices to gather position information. In one embodiment, the signal transmitting device is an existing mobile electronic device. In another embodiment, the signal transmitting device is a radio frequency identification (RFID) tag attached to an entity. In another embodiment, the signal gathering device is a collection of wall mounted antennas. The entity location is calculated by gathering the phase difference or other timing information of signal generated by the signal transmitting device on the entity. This location information is then given to end user applications. One embodiment is a network security application using gathered location information of wireless ethernet cards. Another embodiment is a network resource locator application.

Systems and methods are disclosed for automated notification systems. A representative method, among others, can be summarized by the following steps: monitoring travel data in connection with a mobile thing (MT) that is destined to pickup or deliver an item or service at a stop location; causing initiation of a notification communication session with a personal communications device (PCD) based upon the travel data; and during the notification communication session, enabling a party associated with the PCD to change one or more tasks associated with the pickup or delivery. A representative system, among others, comprises a computer or other automated system that is programmed or designed to perform the foregoing steps.

A geographic-based communications service system has a mobile unit for transmitting/receiving information, and access points connected to a network. The access points are arranged in a known geographic locations and transmit and receive information from the mobile unit. When one of the access points detects the presence of the mobile unit, it sends a signal to the network indicating the location of the mobile unit and the information requested by the mobile unit. Based on the signal received from the access point, the network communicates with information providers connected to the network and provides data to the mobile unit through the access point corresponding to the location of the mobile unit.

Wireless communication system for location of a person and identification of a distress condition of the person comprising portable transceivers (20) carried by persons, each having an associated alarm switch (40), the transceiver activatable locally and/or via a remote network and the alarm switch operable locally to activate the transceiver.

A mobile device, for determining location in a wireless network, includes a motion detector for detecting motion of the mobile device; a memory for storing wireless signal strength calibration data comprising a list of wireless signal strengths and known locations; a location detection module for measuring a wireless signal strength of any received network radio signals and for determining the location of the mobile device with reference to the wireless signal strength calibration data; and a location correction module, for applying a statistical correction to the measured wireless signal strength determined by the location detection module when the motion detector detects that the mobile device is moving less than a threshold amount. The mobile device may further include an orientation detector for detecting the orientation of the mobile device, which can be compared with orientation data stored in the calibration data.

A method of estimating a location of a WLAN-enabled user-device in a WLAN-based positioning system is provided. The WLAN-enabled device receives signals transmitted by WLAN-enabled access points in range of the WLAN-enabled user-device so that observed WLAN-enabled access points identify themselves. The method includes accessing a master database that associates WLAN-enabled access points with corresponding audited locations as determined by an audit of a relatively large geographic area and obtaining location information for any identified WLAN-enabled access point. The method includes accessing a supplemental database to obtain inferred location information corresponding to any identified WLAN-enabled access point. The supplemental database has a relatively small set of WLAN-enabled access points and corresponding inferred locations. The inferred locations are inferred based on input by a user of the WLAN-based positioning system. The method includes estimating a location of the WLAN-enabled user-device based on the audited location information and the inferred location information.

The present invention is for a system and method for determining the proximity of a mobile device to a location without the use of a satellite based or other location awareness system, nor a stationary beacon of any kind Instead, the mobile device monitors radio frequency broadcast identification codes from nearby mobile devices, and determines if the set of detected identification codes is sufficiently similar to a weighted set of identification codes attributed to specified location. If the calculation of similarity meets the confidence conditions of the system, notification is made that the customer or visitor has arrived. The invention utilizes a combination of confidence interval computation, machine learning, and fault tolerance mechanisms to optimize the success of correctly detecting that the device is near the relevant location.

A Wide Area Sensor Network (WASN) is disclosed that utilizes wideband software defined radios (SDRs) to monitor RF energy over a wide frequency range, detect when critical frequencies are being jammed or otherwise interfered with, and locate the source of the interference so that the interference can be eliminated. The WASN may use one or more geolocation techniques In addition, the WASN may detect and locate unauthorized transmitters as well as estimate the transmitted power of authorized transmitters to assure they are not transmitting more power than authorized.

An improved fully-coupled vehicle positioning process and system thereof can substantially solve the problems encountered in global positioning system-only and inertial navigation system-only, such as loss of global positioning satellite signal, sensibility to jamming and spoofing, and inertial solution's drift over time, in which the velocity and acceleration from an inertial navigation processor are used to aid the code and carrier phase tracking of the global positioning system satellite signals, so as to enhance the performance of the global positioning and inertial integration system, even in heavy jamming and high dynamic environments. The improved fully-coupled GPS/IMU vehicle positioning system includes an IMU (inertial measurement unit) and a GPS processor which are connected to a central navigation processor to produce navigation solution that is output to an I/O (input/output) interface.

According to an embodiment of the present invention, a three-dimensional (3-D) energy-based emitter geolocation technique determines the geolocation of a radio frequency (RF) emitter based on energy or received signal strength (RSS) of transmitted signals. The technique may be employed with small unmanned air vehicles (UAV), and obtains reliable geolocation estimates of radio frequency (RF) emitters of interest.

A method for locating a user in a wireless network is disclosed. A mobile computer seeking to determine its location within a building detects the signal strength of one or more wireless base stations placed at known locations throughout the building. The mobile computer uses this measured signal strength to determine its location via a signal-strength-to-location table look-up. A table of known locations within the building and the base station signal strength at those locations is searched to find the most similar stored signal strength to the signal strength detected. The location corresponding to the most similar stored signal strength is determined to be the current location of the mobile computer. Alternatively, a number of signal strengths from the table can be used and the corresponding locations can be spatially averaged to determine the location of the mobile computer. The table can be derived empirically, by placing a mobile computer at the known locations and detecting the signal strength of the wireless base stations at those locations, or the table can be derived mathematically by taking into account a reference signal strength, the distance between the reference point and the known location, and the number of walls between the reference point and the known location. As an alternative, the base stations can detect the signal strength of the mobile computer. In such a case, the table would relate a known position of the mobile computer to the signal strength of the mobile computer at that location as detected by the one or more base stations.

Methods, apparatuses, and systems directed to a wireless node location mechanism that uses a signal strength weighting metric to improve the accuracy of estimating the location of a wireless node based on signals detected among a plurality of radio transceivers. In certain implementations, the wireless node location mechanism further incorporates a differential signal strength metric to reduce the errors caused by variations in wireless node transmit power, errors in signal strength detection, and/or direction-dependent path loss. As opposed to using the absolute signal strength or power of an RF signal transmitted by a wireless node, implementations of the present invention compare the differences between signal strength values detected at various pairs of radio receivers to corresponding differences characterized in a model of the RF environment. One implementation of the invention searches for the locations in the model between each pair of radio receivers where their signal strength is different by an observed amount.

A signal collection system (SCS) is used in a wireless location system that determines the geographical locations of mobile wireless transmitters. The SCS includes a first receiver module, a first digital signal processing (DSP) module, a control and communications module, a timing signal generator including an enhanced GPS receiver, and a bus coupling the DSP module to the communications and control module. The receiver module receives RF signals from the mobile transmitters via a plurality of antennas and digitizes said RF signals, and provides digitized RF data to the first DSP module.

A data processing system and method are disclosed for disabling a portable computer in response to the portable computer being moved outside of an authorized area of use. An authorized, geographical area of use is established. The authorized, geographical area is any geographical area capable of being defined. The geographical area is not limited to areas within an enclosure, and is not bounded by a transmitter's broadcast range. A determination is made regarding whether the portable computer is located outside of the authorized area. If the portable computer is moved outside of the authorized area, the portable computer is disabled. The portable computer is inoperable when disabled.

Embodiments of the present invention include one or more wireless transmitting devices and an array of receiver units for receiving wireless communications from the transmitting devices. The transmitter devices and receiver units can be arranged in one, two or three dimensional configurations. Signals are transmitted from the devices for identification and accurate location determination. Spread spectrum techniques can be used, such as DSSS, FHSS, THSS, and pseudo-noise (PN) coding schemes, or combinations thereof. The transmitting devices can generate one or a plurality of data signals that are orthogonal-code modulated, to be decoded by the receiver units and a processor associated therewith. A plurality of transmitter signals can be received, identified, located, and data demodulated substantially simultaneously using embodiments of the invention. The combined use of array processing methods and diversity schemes can be used to reduce the effects of signal multi-path and occlusion.

An RF object locating system and method that uses or includes a set of N (N>2) receivers (monitoring stations) located at fixed positions in and/or about a region to be monitored, one or more reference transmitters that transmit a timing reference, a location processor that determines object location based on time-of-arrival measurements, and at least one object having an untethered tag transmitter that transmits RF pulses, which may additionally include object ID or other information. Free-running counters in the monitoring stations, whose phase offsets are determined relative to a reference transmitter, are frequency-locked with a centralized reference clock. Time-of-arrival measurements made at the monitoring stations may be stored and held in a local memory until polled by the location processor. The invention permits rapid acquisition of tag transmissions thereby enabling the monitoring of large numbers of objects, and also provides a unique approach to data correlation in severe multipath environments.

A multi-resolution object location system and method for locating objects is provided. The multi-resolution system and method uses a long-range object locator together with a more precise RFID locator to efficiently and accurately determine the location of objects that include an RFID tag. The long-range object locator has a relatively longer range and can cover a relatively large area to determine the general location of the object within the large area. The RFID locator has a relatively shorter range, but is able to locate the object more precisely. The object location system uses the long-range locator to first determine the general location of the object, and then the RFID locator is used to determine a more accurate location of the object. Thus, the multi-resolution object location system is able to provide both a long range location of objects over a large area and a precise location of objects.

Distance to a modulated backscatter tag is measured with a RFID reader that measures changes in phase with frequency of modulated backscattered RF signals. Measured distances are linked to a specific tag. The effects of other sources of reflected and interfering signals are mitigated. The techniques eliminate the need for high RF bandwidth used in time-of-flight methods, and may be used with linear, limiting or other types of amplifiers in the reader receiver. Unambiguous distance to a tag may be found using the derivative of phase with RF frequency of the modulated signal backscattered by a tag. The distance to a tag can be measured with an accuracy on the order of a centimeter. The techniques utilize the characteristics of cooperative backscatter tags (transponders, labels, etc.). New readers implement the techniques which may use unmodified tags.

Navigation method and navigation system for motor vehicles for navigating from a present location to a destination. In response to an emergency user request, an emergency destination closest to the present location is selected from a database, set as the destination, and a route calculated from the present location to the emergency destination. The navigation system includes a memory having a database for emergency destinations and a device for selecting, from the database, an emergency destination closest to the present location.