| TRUEPOSITION, INC. Patent applications |
| Patent application number | Title | Published |
| 20120088522 | Detection and Selection of a Reference Signal for Network-Based Wireless Location - A serving mobile location center (SMLC) receives a position request concerning a mobile-of-interest (MOI) operating in a discontinuous transmission (DTX) mode, and in response a wireless location system (WLS) is tasked to locate the MOI. A plurality of location measurement units (LMUs) are instructed to receive and digitize radio frequency (RF) energy. At the LMUs, a signal of interest is received and cross-correlated with a known training sequence to produce a received detection metric. The detection metric is weighted to favor the MOI even in the presence of interference from other mobile devices. The SMLC selects the LMU with the best weighted detection metric as a reference site and selects two or more LMUs with lesser weighted detection metrics above a threshold as co-operating sites. The received signal of interest is demodulated and demodulated data are distributed to the co-operating sites. The co-operating sites produce a reference waveform and cross-correlate the reference waveform with stored data to produce a TDOA measurement at each co-operating site, and the TDOA measurements are used to compute MOI position information. | 04-12-2012 |
| 20120082255 | Location of Wideband OFDM Transmitters with Limited Receiver Bandwidth - One embodiment takes the form of a system for locating wireless transmitters employing an Orthogonal Frequency Division Multiplexing (OFDM) digital modulation scheme, which comprises transmitting signal components over narrowband frequency channels spanning a wideband channel. The system includes a first receiving system configured to receive a fraction of the signal components transmitted by a first wireless transmitter to be located in a fraction of the narrowband frequency channels, and to process the fraction of the signal components to derive location related measurements. The system further includes at least a second receiving system configured to receive the fraction of the signal components transmitted by the first wireless transmitter, and to process this fraction of the signal components to derive location related measurements. | 04-05-2012 |
| 20120020320 | Network-Based Location of Mobile Transmitters - In an overlay, network-based, wireless location system, LMUs typically co-located with BTSs are used to collect radio signaling both in the forward and reverse channels for use in TDOA and/or AOA positioning methods. Information broadcast from the radio network and by global satellite navigation system constellations can be received by the LMU and used to reduce the difficulty of initial system configuration and reconfiguration due to radio network changes. | 01-26-2012 |
| 20120015670 | Hybrid GNSS and TDOA Wireless Location System - A method and apparatus for position determination is provided using measurements from both Global Positioning System (GPS) receivers and terrestrial-based Uplink Time Difference of Arrival (UTDOA) receivers. The method involves the transformation of downlink satellite measurements into equivalent UTDOA measurements by computing comparable cross-correlation coefficients and time differences of arrival with respect to a UTDOA reference station. The method includes a weighting operation whereby the relative weights of the UTDOA measurements and the relative weights of the GPS measurements are adjusted based on a theoretical scaling followed by empirical adjustments. The method further involves the efficient computation and combining of metrics that are used to minimize the weighted error between candidate location solutions and the UTDOA and GPS measurements. | 01-19-2012 |
| 20110285589 | Network Location and Synchronization of Peer Sensor Stations in a Wireless Geolocation Network - Transmitters are located with a network of sensors by measuring signal characteristics at multiple known locations and processing these measurements at a central node. The sensors communicate their location to the central node along with measured characteristics of the transmitter's signal, and may be required to synchronize with other sensors. Often, GNSS receivers are utilized to locate and synchronize the sensors. However, the GNSS signals may be attenuated by obstructions. In this case, the sensors determine their location by making ranging measurements with sensors that can receive the GNSS signals. The waveform for the wireless backhaul permits this ranging. Additionally, many sensors can determine their location and time synchronize with the geolocation network through reception of signals from other sensors even if they do not have a direct connection to sensors that know their location and are time synchronized. | 11-24-2011 |
| 20110256887 | Mid-Call Synchronization for U-TDOA and AOA Location in UMTS - In a wireless location system, a method for determining frame and slot timing information for use in receiving an uplink signal from a user equipment (UE) device assigned to an uplink Dedicated Physical Control Channel (DPCCH) includes receiving signals in the uplink DPCCH at a location measurement unit (LMU) of the WLS. The method also includes detecting a predefined bit pattern known to be present in a plurality of predefined slots of the uplink DPCCH. Next, the frame and slot timing information are determined for the uplink DPCCH based on the detected bit pattern. Finally, the frame and slot timing information is used for collecting uplink signals from the UE for use in location processing. | 10-20-2011 |
| 20110205108 | Method for Position Estimation Using Generalized Error Distributions - A method for improving the results of radio location systems that incorporate weighted least squares optimization generalizes the weighted least squares method by using maximum a posteriori (MAP) probability metrics to incorporate characteristics of the specific positioning problem (e.g., UTDOA). Weighted least squares methods are typically used by TDOA and related location systems including TDOA/AOA and TDOA/GPS hybrid systems. The incorporated characteristics include empirical information about TDOA errors and the probability distribution of the mobile position relative to other network elements. A technique is provided for modeling the TDOA error distribution and the a priori mobile position. A method for computing a MAP decision metric is provided using the new probability distribution models. Testing with field data shows that this method yields significant improvement over existing weighted least squares methods. | 08-25-2011 |
| 20110159891 | Cooperating Receiver Selection for UMTS Wireless Location - For Wireless Communications Networks (WCNs) that support soft handover, cooperator receiver selection for a TDOA, AOA, TDOA/AOA, or hybrid network-based or network-overlay Wireless Location System (WLS) must contend with one or more network base stations as a serving cell. When the active set contains more than one member, two techniques for determining a set of cooperating and demodulating receivers to use in the signal collection for location estimation is disclosed. In one embodiment, the active set members are constructively reduced to a single member that is used as a proxy serving cell. In another embodiment, the information contained in the active set membership is retained and a new set of demodulating and cooperator receivers are generated based on the entire membership of the active set. | 06-30-2011 |
| 20110159876 | Cooperating Receiver Selection for UMTS Wireless Location - For Wireless Communications Networks (WCNs) that support soft handover, cooperator receiver selection for a TDOA, AOA, TDOA/AOA, or hybrid network-based or network-overlay Wireless Location System (WLS) must contend with one or more network base stations as a serving cell. When the active set contains more than one member, two techniques for determining a set of cooperating and demodulating receivers to use in the signal collection for location estimation is disclosed. In one embodiment, the active set members are constructively reduced to a single member that is used as a proxy serving cell. In another embodiment, the information contained in the active set membership is retained and a new set of demodulating and cooperator receivers are generated based on the entire membership of the active set. | 06-30-2011 |
| 20110151839 | Location Intelligence Management System - Collection and analysis of network transaction information which includes the mobile device's usage, location, movements coupled with data from non-wireless network sources allow for the automation of analysis for the detection of anti-social behaviors. | 06-23-2011 |
| 20110150211 | Passive System for Recovering Cryptography Keys - Modern cellular wireless communications providers strive to keep their network and subscribers secure through various means. The identity of the subscriber may be obfuscated through the use of a temporary identifier for most network transactions including signaling events, voice calls, SMS messages and data sessions. A subscriber's unique identity may only be transmitted over the air in an encrypted form. Similarly, the content of voice calls, SMS messages and data sessions may also be encrypted when transmitted over the air and even when transferred over internal network interfaces. However, the use of encryption presents significant challenges for law enforcement communities when court ordered lawful intercept is required to monitor and locate subscribers utilizing the wireless networks for illegal and/or terrorist purposes. A technique to aid in the determination of a subscriber's unique wireless identity and the decryption of encrypted signals would be very useful for lawful intercept. In this document we describe an architecture and technique to aid in the decryption of encrypted wireless signals for lawful intercept by determining the current encryption key. It may also be used to decrypt encrypted signals on internal interfaces of the wireless and wireline networks. | 06-23-2011 |
| 20110148699 | Satellite Positioning Receiver and Proxy Location System - To reduce power consumption in a user terminal, especially mobile devices, a system and method are introduced that use terrestrial beacons as a location proxy when satellite positioning signals are not available. The geographic locations of the terrestrial beacons need not be known to use the beacons as a proxy for a satellite positioning signals derived location. | 06-23-2011 |
| 20110134240 | Multi-Sensor Location and Identification - By combining imaging systems with wireless location functionality, a subject's videometric signature can be linked to a public identity, thus enabling continuous surveillance outside or between the coverage area of video surveillance networks. In addition to extending the surveillance coverage area, the combination of computerized video surveillance with wireless location determination may also allow for identification of mobile device users via the existing mobile equipment and user identifiers used in the wireless network. | 06-09-2011 |
| 20110033002 | Location of Wideband OFDM Transmitters With Limited Receiver Bandwidth - One illustrative embodiment takes the form of a system for locating wireless transmitters employing an Orthogonal Frequency Division Multiplexing (OFDM) digital modulation scheme. The OFDM scheme comprises transmitting signal components over narrowband frequency channels spanning a wideband channel. The system includes a first receiving system configured to receive a fraction of the signal components transmitted by a first wireless transmitter to be located in a fraction of the narrowband frequency channels, and to process the fraction of the signal components to derive location related measurements. The system further includes at least a second receiving system configured to receive the fraction of the signal components transmitted by the first wireless transmitter, and to process this fraction of the signal components to derive location related measurements. The system also includes a processing system configured to use location related measurements from the first and second receiving systems to compute the location of the wireless transmitter. | 02-10-2011 |
| 20100304763 | System for Automatically Determining Cell Transmitter Parameters to Facilitate the Location of Wireless Devices - Several techniques for locating wireless devices involve the Mobile Stations (MS) making measurements of the signals transmitted by geographically distributed base stations within a wireless network. If some key site information is known about these transmitters, such as the transmitter location, transmit signal power, signal propagation, and transmit signal timing, measurements of these transmit signals by a MS can be used to determine the position of the MS. An automatic method to detect transmitters, identify key transmitter information, and utilize the base station transmit signals to perform location is presented. In addition, this method facilitates the use of cell site transmit signals that are part of multiple wireless networks. | 12-02-2010 |
| 20100273504 | Network Autonomous Wireless Location System - A Network Autonomous Wireless Location System (NAWLS) is designed to allow for precise location of a mobile device (e.g., a cell phone) without interconnection to, and with minimal disruption of, the local wireless communications network. Using distributed radio network monitors (RNM) and a managed network emulator (NE); mobile devices are sampled, acquired or captured. Once triggered by the RNM or NE, an untethered wireless location system (U-WLS) is used to calculate a precise location. The U-WLS; comprising mobile receiver sites, each capable of self location, exchanging information with other components of the NAWLS, and receiving or exchanging signals from the mobile device; utilizes various network-based and handset-based wireless location techniques dependent on the deployed options. In addition, the NAWLS includes data links interconnecting the U-WLS, NE and RNM. | 10-28-2010 |
| 20100227628 | Advanced Triggers for Location-Based Service Applications in a Wireless Location System - Methods and systems are employed by a wireless location system (WLS) for locating a wireless device operating in a geographic area served by a wireless communications system. An exemplary method includes monitoring a set of signaling links of the wireless communications system, and detecting at least one predefined signaling transaction occurring on at least one of the predefined signaling links. Then, in response to the detection of the at least one predefined network transaction, at least one predefined location service is triggered. | 09-09-2010 |
| 20100222081 | Location Quality of Service Indicator - A mobile wireless device is configured to provide a location quality of service indicator (QoSI) indicative of the quality of a calculated location estimation for use by a location-based service. The QoSI may be calculated by the device itself or by a server, such as a location enabling server (LES). The QoSI may be used to represent the predicted location accuracy, availability, latency, precision, and/or yield. | 09-02-2010 |
| 20100166112 | INTEGRATED MICRO-SAMPLING WIRELESS RECEIVER - Disclosed are methods and systems for filtering an intermediate frequency (IF) band when digitizing a radio frequency (RF) signal using a higher Nyquist zone several times above the sampling rate. Undersampling may be employed along with an undersampled Nyquist filtering technique to implement an integrated receiver for base station applications such as wireless base station beacon monitoring. Such a receiver may be integrated into a smaller package and consume less power at a reduced cost. In one embodiment, the receiver may operate at a high RF sampled frequency that is microsampled in the 10 | 07-01-2010 |
| 20100164781 | Method for Position Estimation Using Generalized Error Distributions - A method for improving the results of radio location systems that incorporate weighted least squares optimization generalizes the weighted least squares method by using maximum a posteriori (MAP) probability metrics to incorporate characteristics of the specific positioning problem (e.g., UTDOA). Weighted least squares methods are typically used by TDOA and related location systems including TDOA/AOA and TDOA/GPS hybrid systems. The incorporated characteristics include empirical information about TDOA errors and the probability distribution of the mobile position relative to other network elements. A technique is provided for modeling the TDOA error distribution and the a priori mobile position. A method for computing a MAP decision metric is provided using the new probability distribution models. Testing with field data shows that this method yields significant improvement over existing weighted least squares methods. | 07-01-2010 |
| 20100120447 | Femto-Cell Location by Direct Methods - Illustrative embodiments of the inventive subject matter described herein include, but are not limited to, the following: a femto-cell device, methods for use by a wireless location system (WLS) in locating a femto-cell device, and a wireless location system having certain features relating to the location of femto-cell devices. A femto-cell device used in a wireless communications system (WCS) includes a location subsystem configured to acquire information identifying the geographic location of the femto-cell device. The device also includes an antenna subsystem, a radio frequency (RF) block coupled to the antenna subsystem, a baseband block coupled to the RF block, and a communications block coupled to the baseband block. In addition, the device is configured to communicate with the WCS, including communicating at least some of the location information to the WCS. | 05-13-2010 |
| 20100120435 | Use of Radio Access Technology Diversity for Location - Various aspects are disclosed herein for determining a location estimate for multi-mode mobile devices using measurements from one or more radio access technologies and providing a combined location solution. Using the multiple radio access technology capability of the wireless communications system, a mobile communications device may be located on a first radio network characterized by a first radio modulation technique, radio network topology, and channel bandwidth. The mobile communications device may then be handed off to a second radio network and located using a second radio network characterized by a second radio modulation technique, radio network topology, and channel bandwidth. The two location estimates may then be used to develop a combined location estimate. | 05-13-2010 |
| 20100120394 | Femto-Cell Location by Proxy Methods - Location of small, consumer deployed femto-cells cannot be determined by the usual site survey methods. Location of attached mobiles allows for a proxy location of the femto-cell that can then be used for wireless network planning including the provisioning of a calculated default emergency services location for the femto-cell. | 05-13-2010 |
| 20100052990 | Portable, Iterative Geolocation of RF Emitters - Iterative geolocation of a stationary RF emitter through the use of TDOA may include the use of a single portable geolocation (e.g., TDOA) sensor, a pair of portable geolocation sensors and three of more portable geolocation sensors. Adding portable geolocation sensors to the iterative process reduces the constraints on the signals to be located as well as providing a reduction in the number of iterations required to obtain improved location accuracy. | 03-04-2010 |
| 20100039326 | Variable Coherence Integration for the Location of Weak Signals - In a network-based Wireless Location System (WLS), geographically distributed Location Measurement Units (LMUs) must be able to detect and use reverse channel (mobile to network) signals across multiple BTS coverage areas. By using Matched Replica correlation processing with the local and reference signals subdivided into discrete segments prior to correlation, the effects of mobile clock drift and Doppler shifts can be mitigated allowing for increased processing gain. | 02-18-2010 |
| 20090170528 | Subscriber Selective, Area-based Service Control - A method for use in controlling a mobile device's access to one or more wireless communications networks (WCNs) with an overlaid wireless location system (WLS) includes monitoring a set of one or more predefined signaling links of at least one WCN, and detecting an event associated with the mobile device. Next, using a low-accuracy location function of the WLS, the system determines that the mobile device is within a defined area of interest and is potentially within a defined quiet zone. Next, using a high-accuracy location function of the WLS, the system determines a precise geographic location of the mobile device and based thereon confirms that the mobile device is within the quiet zone or at least within an area of ambiguity around the quiet zone. Finally, the mobile device's access to the wireless communications network is limited, e.g., according to a pre-defined rule established by the carrier. This approach allows finer definition of the fenced area while also minimizing the load on the high-accuracy location function. The proximity threshold is preferably based on the accuracy of the underlying location technology. | 07-02-2009 |
| 20090156228 | Mid-Call Synchronization for U-TDOA and AOA Location in UMTS - In a wireless location system, a method for determining frame and slot timing information for use in receiving an uplink signal from a user equipment (UE) device assigned to an uplink Dedicated Physical Control Channel (DPCCH) includes receiving signals in the uplink DPCCH at a location measurement unit (LMU) of the WLS. The method also includes detecting a predefined bit pattern known to be present in a plurality of predefined slots of the uplink DPCCH. Next, the frame and slot timing information are determined for the uplink DPCCH based on the detected bit pattern. Finally, the frame and slot timing information is used for collecting uplink signals from the UE for use in location processing. | 06-18-2009 |
| 20090149132 | Detection of Time of Arrival of CDMA Signals in a Wireless Location System - In a Wireless Location System (WLS) deployed in connection with a CDMA-based wireless communications system, Location Measurement Units are used to collect multi-path corrupted radio signaling for use in time difference of arrival (TDOA) and hybrid positioning methods. Signal processing techniques are used to enhance the WLS's ability to determine the minimally time-delayed multi-path component and thus increase the accuracy of the TDOA location in CDMA-based wireless communications systems. The signal processing includes a filtering technique for reducing the leading sidelobes of the cross-correlation function as well as a leading edge discovery procedure. | 06-11-2009 |
| 20090143018 | Automated Configuration of a Wireless Location System - In an overlay, network-based Wireless Location System, Location Measurement Units (LMUs) are used to collect radio signaling both in the forward and reverse channels for use in TDOA and/or AoA positioning methods. Information broadcast from the radio network and by global satellite navigation system constellations can be received by the LMUs and used to reduce the difficulty of initial system configuration and reconfiguration due to radio network changes. | 06-04-2009 |
| 20090005061 | LOCATION QUALITY OF SERVICE INDICATOR - A mobile wireless device is configured to provide a location quality of service indicator (QoSI) indicative of the quality of a calculated location estimation for use by a location-based service. The QoSI may be calculated by the device itself or by a server, such as a location enabling server (LES). The QoSI may be used to represent the predicted location accuracy, availability, latency, precision, and/or yield. | 01-01-2009 |
| 20080248811 | TDOA/GPS Hybrid Wireless Location System - A method and system for enhancing the accuracy and robustness of locations determined for a mobile wireless transceiver in a cellular telephone communications system integrating location-related information both from an assisted GPS device embedded in the mobile unit and from infrastructure-based facilities that extract signal characteristic data at networked base stations. Available supporting collateral information may be additionally evaluated in the location determinations to provide location estimates of enhanced robustness and accuracy. | 10-09-2008 |