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John Carlson, Dulles US

John Carlson, Dulles, VA US

Patent application numberDescriptionPublished
20080214184SYSTEM AND METHOD TO MODIFY WIRELESS NETWORK CALIBRATION DATA - A system and method to re-calibrate an area of a wireless communications network that has been exposed to one or more network configuration changes is disclosed. When one or more attributes of the wireless network undergo a change which impairs the geo-location capability to locate a mobile station, it can be detrimental to the safety and well being of the network users. Geo-location calculations rely on accurate and updated calibration data to correctly locate a mobile station. In some instances, it may be necessary to update the calibration data for areas of the network that have been exposed to network configuration changes. Modifying previously collected calibration data to account for changes that have occurred in the network may increase the accuracy of mobile station location estimation.09-04-2008
20080214205SYSTEM AND METHOD FOR GENERATING A LOCATION ESTIMATE USING A METHOD OF INTERSECTIONS - The location of a wireless mobile device may be estimated using, at least in part, one or more pre-existing Network Measurement Reports (“NMRs”) which include calibration data for a number of locations within a geographic region. The calibration data for these locations is gathered and analyzed so that particular grid points within the geographic region can be determined and associated with a particular set or sets of calibration data from, for example, one or more NMRs. Regions may be defined as a function of any number of parameters and respective predetermined ranges thereof in the NMRs. An intersection of these defined regions may be determined and the location of a mobile device may be estimated as a function of the intersection.09-04-2008
20080274750SYSTEM AND METHOD FOR ESTIMATING THE LOCATION OF A MOBILE DEVICE - A system and method for estimating the location of a mobile station that receives signals from a plurality of base stations. The base station timing offsets may be estimated utilizing an observed time difference of arrival value at the mobile between a first signal received from a first base station and a second signal received from a second base station. An initial location for the mobile is randomly selected and an estimated location is determined using the selected initial location, the observed time difference of arrival value, and an iterative search algorithm. The estimated location may be stored if the estimated location is within a predetermined area. In addition, for each such estimated location, the applicable base station time offsets that relate to this location may be updated to generate a current best estimate. A calculated location for the mobile may be determined from stored estimated locations and the current base station time offset estimates.11-06-2008
20080285505SYSTEM AND METHOD FOR NETWORK TIMING RECOVERY IN COMMUNICATIONS NETWORKS - A system and method for determining the network timing of a communications network from a mobile station that receives signals from a plurality of base stations. An estimated location of a mobile station may be determined through any number of or combination of location technologies. Network measurements such as observed time difference values and/or a round trip time values at the mobile station or base stations in the network may be utilized. Network timing relationships may be determined as a function of the estimated location and network measurements. An estimated location of a second mobile station may be determined as a function of the network timing relationships.11-20-2008
20080287139SYSTEM AND METHOD FOR ESTIMATING THE LOCATION OF A MOBILE STATION IN COMMUNICATIONS NETWORKS - A system and method for estimating the location of a mobile station that receives signals from a plurality of base stations. An estimated location of a mobile station may be determined through any number of or combination of location technologies. Network measurements such as observed time difference values and/or a round trip time values at the mobile station or base stations in the network may be utilized. Network timing relationships may be determined as a function of the estimated location and network measurements. An estimated location of a second mobile station may be determined as a function of the network timing relationships.11-20-2008
20080293435Method and apparatus to select an optimum site and/or sector to provide geo-location data - A system and method selects secondary base stations to task that provide geo-location information used to geo-locate a mobile station. A network overlay location system may be co-located at base station sites of a wireless communications network. The location measurement units of the network overlay system provide location information of the mobile station, which may be determined via one or more geo-location techniques, for example: time of arrival (TOA), time difference of arrival (TDOA), uplink time difference of arrival (UTDOA), angle of arrival (AOA), signal power, radio fingerprinting etc. Selecting secondary base stations to task using various selection criteria may provide optimum results when geo-locating a mobile station.11-27-2008
20090124266Ranging in UMTS networks - A method and system for determining an approximate range from a location measurement unit to a mobile device. An uplink signal from the mobile device is received by the location measurement unit, and an uplink frame marker is determined from the uplink signal. A downlink signal is received at the location measurement unit from a base station serving the mobile device, and a downlink slot marker is determined from the downlink signal. A round trip propagation delay is determined based upon the uplink frame marker and the downlink slot marker, and an approximate range from the location measurement unit to the mobile device is determined as a function of the round trip propagation delay.05-14-2009
20090131073SYSTEM AND METHOD FOR LOCATING UMTS USER EQUIPMENT USING MEASUREMENT REPORTS - A system and method for estimating a location of a wireless device receiving signals from a plurality of nodes of a communication system. A first value may be determined based on a network timing characteristic for one of the nodes, and a second value may be determined based on a network measurement report characteristic. An observed time difference of arrival (“OTDOA”) hyperbola may then be calculated based on the first and second values, and a location of the wireless device estimated as a function of the OTDOA hyperbola.05-21-2009
20090174600SYSTEM AND METHOD FOR DETERMINING THE GEOGRAPHIC LOCATION OF A DEVICE - A method and apparatus for estimating a location of a device. For each of a plurality of locations of a device, a set of positional data is determined from signals received from a plurality of satellites. The positional data is filtered and compared with data from a road network database. This comparison may be a function of a distance from at least one point defined by a set of the filtered positional data to a road in the road network database and an angle between a line representing a best fit for plural points defined by corresponding plural sets of the filtered positional data to a line defined by a road in the road network database.07-09-2009
20090177382Calibration of a Navigation System - A method and apparatus for correcting position error in a navigation system. A first set of positioning measurements of a device are determined from signals received from a first plurality of sources and a second set of positioning measurements of the device are determined from signals received from a second plurality of sources. A database comprising map-related information of a predetermined region is provided and a location of the device as a function of the first and second set of positioning measurements and selected map-related information is estimated. Errors in future estimated locations in a navigational system may be compensated by determining a divergence of the second set from the first set of positioning measurements. A navigational system that refines its accuracy over time is demonstrated whereby current estimates of location may be improved and data mapping utilized for future location estimates may be updated.07-09-2009
20090201207METHOD TO MODIFY CALIBRATION DATA USED TO LOCATE A MOBILE UNIT - A method of modifying calibration data used to geo-locate a mobile station located in an indoor environment is disclosed. When a mobile station is located indoors, the signal strength of signals received and/or transmitted by the mobile station have the tendency to be lower than the strength of the signals received by a mobile station located outdoors. As a result of these lower signal strengths, geo-location efforts which rely on signal strengths may result in unsatisfactory location accuracy. Modifying pre-existing calibration data obtained outdoors may provide a way to simulate indoor calibration data characteristics.08-13-2009
20090275344NETWORK MEASUREMENT REPORT CACHING FOR LOCATION OF MOBILE DEVICES - A system and method for determining an approximate location of a mobile device. The occurrence of a predetermined event may be determined at a first node of a network. Measurement data associated with the mobile device may be stored at a second node of the network. An attempt may be made to determine a location of the mobile device using a first location methodology. Upon failure of the location attempt, the mobile device data may be received at a third node of the network from the second node. At the third node an approximate location of the mobile device may be determined using the mobile device data.11-05-2009
20100087204SYSTEM AND METHOD OF UMTS UE LOCATION USING UPLINK DEDICATED PHYSICAL CONTROL CHANNEL AND DOWNLINK SYNCHRONIZATION CHANNEL - A system and method for estimating a location of a wireless device in a wireless communication system having a plurality of nodes and a plurality of location measurement units (“LMUs”). A set of signal samples from a first wireless device and a second wireless device may be collected by one or more LMUs in a search window. A first time of arrival (“TOA”) is determined, and a second search window is estimated as a function of the first TOA. A second TOA may be determined within the second search window at a second node or one of the LMUs from the set of signal samples. A range estimate of the wireless device may then be determined, and an estimated location of the wireless device may be determined as a function of the first uplink TOA, the second uplink TOA, or the range estimate and second TOA.04-08-2010
20100316092SYSTEM AND METHOD FOR DETECTING SPREAD SPECTRUM SIGNALS IN A WIRELESS ENVIRONMENT - An apparatus for detecting a spread spectrum signal in a wireless signal environment includes at least one antenna for receiving spread spectrum signals, such as UMTS signals, from a signal source in the wireless signal environment. In one embodiment, a detection circuit is configured for correlating a code in signal received by the apparatus with a set of possible codes for spread spectrum signals in order to detect the existence of a spread spectrum signal. In another embodiment, a detection circuit is configured for obtaining at least one reference frame of data from a received signal. The detection circuit is further operable for correlating a segment of the reference frame with a repeated segment of at least one subsequent frame of data in order to detect the existence of a spread spectrum signal. A repeater might incorporate such an apparatus wherein the variable gain of the repeater is adjusted based upon the correlation and the detection of a spread spectrum signal.12-16-2010
20100329311UPLINK SIGNAL DETECTION IN RF REPEATERS - A method for detecting an IS-95 signal without knowledge of a spreading code for the IS-95 signal is provided. A received baseband signal is rotated through a plurality of phase-shifts. For each phase-shifted baseband signal, an in-phase component or a quadrature component of the phase-shifted baseband signal is realigned. The in-phase and quadrature components are multiplied by a PN short code to partially despread the components. The partially despread in-phase and quadrature components are multiplied and integrated. The integrated despread in-phase and quadrature components are compared to a threshold value. In response to exceeding the threshold value, the received baseband signal is identified as an IS-95 signal. The method may be implemented on a repeater for repeating signals between multiple sources.12-30-2010
20110092226Method and Apparatus to Select an Optimum Site and/or Sector to Provide Geo-Location Data - A system and method selects secondary base stations to task that provide geo-location information used to geo-locate a mobile station. A network overlay location system may be co-located at base station sites of a wireless communications network. The location measurement units of the network overlay system provide location information of the mobile station, which may be determined via one or more geo-location techniques, for example: time of arrival (TOA), time difference of arrival (TDOA), uplink time difference of arrival (UTDOA), angle of arrival (AOA), signal power, radio fingerprinting etc. Selecting secondary base stations to task using various selection criteria may provide optimum results when geo-locating a mobile station.04-21-2011

Patent applications by John Carlson, Dulles, VA US