Abstract: A multiple phase state near-field electromagnetic location and communication system includes a multiple phase state near-field transmitter, and a near-field locator receiver. The near-field transmitter is capable of operation in at least two states and each of these at least two states generates a state characteristic difference detected at the near-field locator receiver. The state characteristic difference may be employed for location determination, communication or both. The present invention is particularly well-suited for use in conjunction with a near-field electromagnetic ranging system.
Type:
Grant
Filed:
February 23, 2009
Date of Patent:
August 28, 2012
Assignee:
Q-Track Corporation
Inventors:
Hans Gregory Schantz, Andrew Compston, Robert DePierre, James Matthew Barron
Abstract: Provided is an apparatus and method associated with a location based service, and an apparatus for integrated positioning that may sense positioning-associated information that is in proximity to a user. The apparatus may hierarchically classify the sensed positioning-associated information into multiple categories of accuracy based on a predetermined criterion, and estimate the location of the user in order of low accuracy information to more precise accuracy information.
Type:
Application
Filed:
February 8, 2012
Publication date:
August 9, 2012
Inventors:
Eung Sun KIM, Do Hyung PARK, Yoon Chae CHEONG, Ki Ho KIM
Abstract: Methods and apparatus to visualize locations of radio frequency identification (RFID) tagged items are described. One example method includes receiving a request from a portable electronic device to access product information associated with an individual radio frequency identification (RFID) tagged item, determining a location of the product information in a database, transmitting the located product information to the portable electronic device for display thereon, receiving modified product information associated with the individual RFID tagged item from the portable electronic device, and storing the modified product information to the location of the product information in the database.
Abstract: A method and system for provision of a notification based on location of a target device and heuristic information, the method maintaining, in a storage module, a location profile of a target mobile device based on heuristic information for the target mobile device; receiving the current location of the target mobile device; verifying whether the current location deviates from the location profile; and if the current location deviates from the location profile, triggering a notification to an observer device.
Abstract: Methods and systems are disclosed for radio positioning of a mobile receiver using a virtual positioning reference established by logging a known position of the mobile receiver together with a local time at which a first instance of a predictably repeated code word is received by the mobile receiver from a terrestrial radio signal transmitter. During movement of the mobile receiver from the first known position to a second unknown position, a local clock is used to determine the time difference between when the virtual positioning reference is predicted to receive a second instance of the code word and when the mobile receiver actually receives the second instance of the code word.
Abstract: A data processing apparatus including a data file storing section storing data files; a user interface section assigning first objects to respective data units, displaying the first objects on-screen, and accepting an operation on the data files in the form of an operation on the first objects, the data units each being a data file or a group of a plurality of data files stored in the data file storing section; a condition acquisition section acquiring a condition on attribute information attached to the data units, pertaining to contents of the data units; and a judgment section displaying on-screen a second object to which a function of searching for a data unit conforming to the condition is assigned, moving the second object within the screen according to an instruction from a user.
Abstract: Embodiments herein may use first and second path loss values L1 and L2 to calculate first and second distances R1 and R2 between the MS and first and second base stations BS1 and BS2, respectively, in a wireless packet-carrying network. L1 and L2 may comprise values of a reduction in signal strength of signals as transmitted by the BS1 and the BS2 and as received by the MS. The MS may triangulate its position relative to a grid using R1 and R2. Other embodiments may be described and claimed.
Abstract: A multilateration system and method includes a plurality of receiver stations for receiving signals from an aircraft, and a controller that derives the position of the aircraft by applying a multilateration process to outputs from the receiver stations. For this purpose, the controller determines the altitude of the aircraft and selects a multilateration process that is to be used for position determination, based on the determined altitude.
Abstract: An object of the present invention is to implement accurate positioning of a mobile communication terminal even in an environment in which delay waves are included in radio waves arriving at the mobile communication terminal from radio wave sources.
Abstract: A system and a method for enabling a Home-SUPL Location Platform (H-SLP) to rapidly identify a currently available positioning method of a target SUPL-Enabled terminal (target SET) are provided. To this end, a message, including positioning capabilities (SET capabilities) which represent whether one or more positioning methods exist, to be transmitted from the target SET to the H-SLP is configured to additionally include information representing whether each positioning method is currently available. Accordingly, even if an electric wave environment of the target SET is changed or a positioning method is changed, the H-SLP can rapidly and efficiently perform a positioning because it always recognizes a currently available positioning method.
Abstract: A linear least squares (LLS) estimator provides a low complexity estimation of the location of a mobile terminal (MT), using one of the fixed terminals (FTs) as a reference FT to derive a linear model. A method for selecting a reference FT is disclosed, which improves the location accuracy relative to an arbitrary approach to selecting the reference FT. In addition, a covariance-matrix based LLS estimator is proposed in line-of-sight (LOS) and non-LOS (NLOS) environments to further provide accuracy, taking advantage of the correlation of the observations. Different techniques for selecting the reference FT under non-LOS (NLOS) conditions are disclosed. A map-based two-stage LLS estimator assists in selecting the reference FT under NLOS conditions.
Abstract: The present invention relates to a system and method for positioning and navigation using hybrid spectral compression and cross correlation signal processing of signals of opportunity, which may include Global Navigation Satellite System (GNSS) as well as other wideband energy emissions in GNSS obstructed environments. Examples of these signals of opportunity include but are not limited to GPS, GLONASS, cellular Code Division Multiple Access (CDMA) communications signals, and 802.11 Wi-Fi. Combining spectral compression with spread spectrum cross correlation enables extraction of code and carrier observables without the need to implement the tracking loops (e.g. Costas tracking loop) commonly used in conventional GNSS receivers. For applications where dynamics and transmission medium may make it difficult to continuously track carrier phase, the hybrid approach of the present invention has significant utility.
Abstract: 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.
Abstract: A method for tracking a moving platform (MP) wherein the MP uses an on-board navigation system (NS). Data provided by the navigation system on board the moving platform (MP) is merged with data obtained using a tracking system that tracks the MP from another location. A typical navigation system on board the moving platforms is an inertial navigation system (INS). State data of one or more MP is sent to a processing facility and state data of one or more electromagnetic tracking (EMT) is collected by one or more processing facility. The collected states data from the sources are processed, using the one or more processing facilities for calculating tracking data are used to direct one or more antennas for MP tracking. The state data from one or more MP's are sent using a communications channel.
Abstract: A mobile phone and a method for displaying measurement unit conversion tool thereof are provided. The method for displaying measurement unit conversion tool of the mobile phone includes the following steps. Firstly, a global positioning system (GPS) signal is captured. Next, a classification of measurement unit is obtained by analyzing the GPS signal. Then, at least a particular measurement unit is obtained according to the classification of measurement unit. Lastly, the particular measurement unit is displayed on the unit conversion tool.
Abstract: Apparatus for determining an estimated value for a location of a receiving element within a reference system which may receive signals of a signal source movable to different measuring positions, it being possible to measure—on the basis of the signals received—localization data which indicate a relative location of the receiving element with respect to the movable signal source, the apparatus being configured to determine the estimated value on the basis of at least two different measuring positions and localization data corresponding thereto by means of an evolutionary algorithm. On the basis of the localization data measured, a fitness function of the evolutionary algorithm is formed, the localization data having an angle of arrival of the received signals on the receiving element, and/or a signal arrival time from which a distance from the signal source may be determined.
Type:
Application
Filed:
November 4, 2011
Publication date:
June 7, 2012
Inventors:
Thorsten Edelhaeusser, Joerg Nilson, Hans Holm Fruehauf
Abstract: A rover processor determines position of a rover based upon the interaction between multiple antennas located at the rover and multiple antennas located at a base. The rover antennas may include a rover master antenna having a phase center located at the centroid of the antennas patterns of at least two auxiliary rover antennas. The rover processor may determine the position of the rover master antenna based upon the relative positions of at least two rover antennas (e.g., the rover master antenna and at least one rover auxiliary antenna, or at least two rover auxiliary antennas) with respect to at least two antennas of a base transceiver.
Type:
Application
Filed:
February 8, 2012
Publication date:
June 7, 2012
Applicant:
JAVAD GNSS, Inc.
Inventors:
Javad Ashjaee, Lev B. Rapoport, Dmitry Kinkulkin, Vladimir Yefriemov
Abstract: A system and method for estimating a geolocation of a non-cooperative target using any reasonable target location estimate. Collectors may acquire actual signal measurements including a direction of arrival (DOA), a target range, a time difference of arrival (TDOA), a range rate, a range sum, and/or a frequency difference of arrival (FDOA). A processing device may receive the actual signal measurements and navigational data regarding the collectors. Then, the processing device may calculate an estimated target location as a solution to a nonlinear optimization problem where an objective function to be minimized is a weighted sum-of-squares of differences between the actual signal measurements and calculated values corresponding to signal measurements that theoretically should be produced for a particular target location. The algorithm used to solve this problem may be a globally convergent algorithm, such as a Levenberg-Marquardt algorithm.
Abstract: The present subject matter discloses a method for estimating dilution of precision (DOP) across a service area. A Monte Carlo simulation is used to determine the DOP across a service area. Random points are selected across a service area and as well as the radio transmitters who signals are capable of being received at the random points are determined. Using the network topology of radio transmitters, a DOP is calculated for each of the random points. DOP is modeled for the service area as a function of the calculated DOP for each of the random points. The modeled DOP is used to determined the measurement accuracy required for subsequent location requests.
Abstract: In one embodiment of the invention, a location system is provided using both RF and IR signals for the determination of an object. Another embodiment of the invention provides a direct network connection for a receiver. The direct connection may be provided for connection to an Ethernet network, a telephone network, a cable TV network, a UTP network, a Universal Serial Bus (USB), a medical telemetry network or the Internet. A web server is optionally provided according to an embodiment of the invention. According to a further embodiment, a fixed location identifier is provided to receive signals from a transmitter and then transmit a signal to a receiver, which may be connected to a network. According to a further embodiment, two identifiers may be transmitted, one identifier corresponding to an object, while a second identifier identifies a group designator of the object.
Abstract: Relatively short turnaround times are provided in conjunction with two-way ranging to, for example, facilitate accurate ranging measurements when the relative clock drift between ranging nodes (e.g., devices) is relatively high. In some aspects, relatively short turnaround times are achieved through the use of a symmetric channel that is defined to enable concurrent transmission of ranging messages between nodes. For example, a symmetric channel may be established by configuring the nodes to receive one or more pulses associated with a received ranging message in between pulse transmissions associated with a transmitted ranging message. In this way, one node may send a ranging timestamp shortly after the other nodes sends its ranging timestamp, thereby mitigating the impact of the clock drift on the ranging measurements. In some aspects the pulses may comprise ultra-wideband pulses.
Type:
Grant
Filed:
March 11, 2009
Date of Patent:
May 22, 2012
Assignee:
QUALCOMM Incorporated
Inventors:
Amal Ekbal, David Jonathan Julian, Zhanfeng Jia
Abstract: The present invention relates to a method and devices for determining the position of a user equipment in a mobile radio communications system. According to the invention, the position is determined via a distortion in a radio signal transmitted to or from the user equipment, wherein the distortion is caused by a scatterer being positioned at a particular location and having time-dependent scattering properties such that the scattering of a radio signal gives rise to a distortion by which said scattering properties may be identified.
Abstract: An apparatus and method for determining real time location of assets by calculating the relative position of a plurality of GPS enabled devices transported together, taking advantage of multiple GPS enable devices being transported together including dual band GPS and averaging location data between US and European GPS data. Additionally, an IMB acts to receive GPS data from multiple devices in a shipment and IMB combines and averages data from both GPS systems to create more liable location determination.
Abstract: A mobile computing device comprises a wireless transceiver and a processing circuit. The processing circuit is configured to store a data set for a predetermined location, the data set comprising location data and a location name. The processing circuit is further configured to compare a current location to the location data, to compare an updated location to the location data at a time calculated based on heuristic data, and to generate a notification message based on the mobile computing device arriving proximate to the predetermined location.
Abstract: A positioning method for a sensor node is provided, and the method includes steps of: providing a first antenna having a first omnidirectional radiation pattern on a first plane; rotating the first antenna about an axis substantially parallel to the first plane; transmitting a wireless signal while the first antenna rotates about the axis for every a predetermined central angle; receiving the wireless signal at the sensor node; obtaining Received Signal Strength Indications (RSSIs) of the respective wireless signals; and determining a location of the sensor node according to the RSSIs.
Abstract: Apparatus having corresponding methods and computer-readable media comprise a first receiver to receive a wireless television signal; a first measurement unit to generate a measurement of the wireless television signal; wherein a position of the apparatus is determined based on the measurement of the wireless television signal; a second receiver to receive a wireless local area network (WLAN) signal; and a second measurement unit to generate a measurement of the WLAN signal; wherein a position of a transmitter of the WLAN signal is determined based on the position of the apparatus and the measurement of the WLAN signal.
Type:
Grant
Filed:
January 12, 2007
Date of Patent:
April 3, 2012
Assignee:
TruePosition, Inc.
Inventors:
Matthew Rabinowitz, Todd Young, James J. Spilker, Jr.
Abstract: A method of locating a mobile communications device, in particular on a known path, the mobile device communicating with a mobile communications network infrastructure including a plurality of base stations, communications between the mobile device and the base station to which it is attached having a timing advance to compensate for a time taken for a radio signal to reach the base station from the mobile device, the method comprising: reading a time ordered sequence of messages captured from said communications between the mobile device and said network infrastructure; reading timing advance information from said captured messages; identifying a step change in timing advance using said timing advance information; and determining a location of said mobile devices, in particular on said path, at a time of said step change.
Abstract: A method and system for determining which vessel a container is loaded on. Independent location information received from the container and a vessel is compared to determine a distance between the vessel and the container. If the distance is within the length of the vessel, the container is loaded on the vessel.
Type:
Grant
Filed:
January 8, 2008
Date of Patent:
March 20, 2012
Assignee:
International Business Machines Corporation
Abstract: 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.
Abstract: A system and method for determining the position and orientation of a handheld device relative to a known object is presented. The system comprises a handheld device having an inertial measurement unit and a sighting device, such as a laser pointer, that are used to determine the position of the handheld device relative to a target object, such as a structure, aircraft, or vehicle. The method comprises calibrating a handheld device to find the current location of the handheld device relative to a target object, tracking the movement of the handheld device using an inertial measurement unit, and presenting an updated position of the handheld device relative to a target object.
Abstract: A multilateration system and method includes a plurality of receiver stations for receiving signals from an aircraft, and a controller that derives the position of the aircraft by applying a multilateration process to outputs from the receiver stations. For this purpose, the controller determines the altitude of the aircraft and selects a multilateration process that is to be used for position determination, based on the determined altitude.
Abstract: A positioning method is disclosed. The positioning method includes providing a reference information comprising a plurality of predetermined RSSI values corresponding to a plurality of directional antennas receiving signals from a plurality of areas, utilizing the plurality of directional antennas to scan and detect a wireless communication device, calculating a plurality of RSSI values corresponding to the wireless communication device for the plurality of directional antennas, comparing the plurality of detected RSSI values with the reference information to generate a comparison result, and determining a location position of the wireless communication device according to the comparison result.
Abstract: A mobile wireless device receives a set of fingerprint prediction maps, e.g., RF signal prediction maps, and corresponding probability metrics, e.g., indicative of map reliability. A fingerprint prediction map is an expected signal measurement map corresponding to a parameter or parameters to be measured and a area given a set of expected conditions. At different times, e.g., due to different conditions, a different map in the set of fingerprint prediction maps may be more likely to be accurate. The mobile wireless device updates the probability metrics, associated with different alternative maps in the set of maps, as a function of one or more of: known information, sensor readings, measurements, detected information, and position determination. The mobile wireless device determines its current position using fingerprint predication maps and one or more updated probability metrics.
Type:
Application
Filed:
September 3, 2010
Publication date:
March 8, 2012
Applicant:
QUALCOMM Incorporated
Inventors:
Aleksandar Jovicic, Cyril Measson, Thomas Richardson
Abstract: An apparatus and method for tracking a target wherein a new position fix is taken when the measured movement of the target is more than a predetermined threshold amount or when the position fix has not been updated in a predetermined interval. The apparatus and method manage energy use and network resources when performing position determination fixes.
Type:
Grant
Filed:
October 10, 2008
Date of Patent:
March 6, 2012
Assignee:
QUALCOMM Incorporated
Inventors:
Alecsander P. Eitan, Alexandru Hodisan, Ziv Kahana
Abstract: The subject of the invention is a system or a method of determining the position of the radio signal receiver with respect to the radio signal transmission from a single moving transmitter with one or more antennas or from one static transmitter with one or more static or moving antennas. In order to determine the signal receiver position, three or more signals from different positions or points (antennas) of a single signal transmitter are needed. The transmitted signals include information on latitude, longitude and altitude of individual antennas, and the exact time of signal transmission with respect to the time recorded on the transmitter itself. The signal receiver uses the abovementioned information to calculate its own position.
Abstract: A system is employed for defining a position (location) of a receiving element inside an area surrounded by a wire loop, along the perimeter (a perimeter wire loop), of a work area or other bounded area. In particular, the system can determine whether the receiver is inside or outside the loop, and evaluate its distance from the perimeter wire.
Abstract: 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.
Abstract: In certain embodiments, an apparatus comprises an input and one or more processors. The input receives known locations of wireless mobile nodes over a wireless link. The one or more processors determine geometric features associated with the locations, and calculate an apparatus location of the apparatus from the known locations and the geometric features.
Abstract: A method for receiving verification that a source is authorized to provide mobile-computing-device policies for a first physical location. The method may include receiving a first mobile-computing-device policy and identifying the first physical location. The method may also include associating the first mobile-computing-device policy with the first physical location and implementing, based on the verification, the first mobile-computing-device policy at the first physical location. Systems and computer-readable media for verifying that a source is authorized to provide mobile-computing-device policies for a first physical location are also disclosed.
Abstract: Provided is a method for facilitating location determination. The method includes granting a subscriber access to a location determination network via a first device and determining location of a second device via the network, the second device being configurable for dual mode location determination. Finally, the determined location of the second device is provided to the first device.
Type:
Application
Filed:
August 12, 2011
Publication date:
February 2, 2012
Applicant:
Eikonik Inc.
Inventors:
Philip SHAW, Thomas R. McKnight, JR., Rauni Lindross, Rudy Yukich, Roslyn Honsberger
Abstract: Methods and apparatus, including computer program products, implementing and using techniques for using a location aware device to determine a current location, recording a location bookmark for the current location using the location aware device, storing the location bookmark, detecting at some later time that a location of the location aware device is within a specified proximity to the bookmark location and that a user-defined condition is satisfied by the bookmark content, and automatically notifying a user of the location aware device of the location bookmark. A location bookmark includes a bookmark location and bookmark content, the bookmark location being the current location and the bookmark content including data associated with the current location.
Abstract: A positioning module positions a location of a mobile communication apparatus. A processor determines whether the location falls within a predetermined range, wherein the predetermined range is equal to or greater than an effective communication coverage of a neighboring base station. If the processor determines that the location is within the predetermined range, a signal detection module measures the signal from the neighboring base station. By detecting the signals of the neighboring base stations earlier, the present invention is able to function while the mobile communication apparatus moves at high speeds and successfully switch the connections between the base stations.
Abstract: A method for monitoring and tracking the position of a subject comprises, in an exemplary embodiment, the steps of embedding a transponder into an article to be worn by the subject and installing software in a GPS-enabled receiver, such as a cell phone or the like, for synchronizing and communicating with the transponder. The receiver is to be maintained by a user, such as a guardian or the like, and stores a unique transponder code, allowing the receiver to synchronize with the transponder. The receiver may remotely activate the transponder manually or automatically, at which point the receiver triangulates the geographic position of the transponder and determines distance and direction of the transponder from the receiver in order to guide the user in the direction of the transponder. In further embodiments, the receiver communicates the subject's information and tracking code to other subscribing receivers to increase the number of searchers.
Type:
Grant
Filed:
August 14, 2009
Date of Patent:
January 24, 2012
Inventors:
Barry Brucker, Nadeepuram K. Ranganathan
Abstract: The invention provides a method for guiding a mobile communication device in a wireless communication network. At first, the method according to the invention determines a plurality of referenced positions covered in the wireless communication network. Afterward, the method obtains a plurality of communication quality parameters which each corresponds to one of the plurality of referenced positions. Next, the method transmits the plurality of referenced positions and the plurality of communication quality parameters to the mobile communication device and receives a target position from the mobile communication device. Then, the method determines a current position relative to the mobile communication device. Finally, according to the target position and the current position, the method generates a guiding information and transmits the guiding information to the mobile communication device.
Abstract: The invention relates to a system and method for localization positioning in lighting systems. At least two of a Time Difference of Arrival (TDOA), Angle of Arrival (AOA), Received Signal Strength Index (RSSI) and a Position Estimation Algorithm with unified TDOA and RSSI are used to obtain localization positioning. The schemes introduce a maximum-likelihood estimation strategy incorporating a partial derivative matrix for each lighting unit using at least two reference nodes in order to achieve higher accuracy.
Abstract: Techniques are disclosed for detecting, identifying, and/or geolocating RF communications devices, such as FRS radios, high-power cordless phones, cellular phones, and other wireless communications receiver devices. The techniques exploit a vulnerability present in such devices, and can be used to detect (e.g., up to 300 meters) and geolocate (e.g., within +/?3 meters) those devices. The vulnerability is that receiver circuitry of the target devices emanate RF mixing products when flooded with RF energy or suitable stimulus signal. Such a response to a stimulus signal is unexpected or otherwise unintentional, as receiver circuitry is generally not designed to transmit information. The RF frequency, phase, and amplitude of these sideband RF responses can be used to detect and location the devices. The techniques work in the presence of interference, and can be used on devices that are powered on or off.
Type:
Grant
Filed:
June 18, 2009
Date of Patent:
January 3, 2012
Assignee:
BAE Systems Information and Electronic Systems Integration Inc.
Inventors:
Milton Janosky, Tyler Robinson, John J. Kelly, Peter Dusaitis
Abstract: A weather radar system or method can be utilized to determine a location of a weather hazard for an aircraft. The weather radar system can utilize processing electronics coupled to an antenna. The processing electronics can determine presence of the hazard in response to data related to returns received by the weather radar antenna and data from a lightning sensor. The system can include a display for showing the hazard and its location.
Abstract: A device for estimating a current orientation of a mobile terminal device at a current geographical position, wherein, at the current geographical position, a current measurement package may be determined which has a transmitter identification and an electromagnetic signal characteristic of a radio transmitter which may be received at the current geographical position with the current orientation of the mobile terminal device at a current measurement time, with a determiner for determining an accordance measure between the current measurement package and a reference measurement package, which has a transmitter identification, a reference orientation and an electromagnetic signal characteristic of a reference radio transmitter which was receivable at a geographical reference position allocated to the reference measurement package with the reference orientation at a reference time lying before the current measurement time, a selector for selecting at least one reference measurement package which has an accordan
Type:
Application
Filed:
April 22, 2011
Publication date:
December 29, 2011
Inventors:
Steffen Meyer, Juergen Hupp, Stephan Haimerl
Abstract: Determining the location of a station or potential rogue access point in a wireless network including accepting an ideal path loss model and calibrating the ideal model using path loss measurements between access points at known locations. The calibrating determines a calibrated path loss model between the access points. The method further includes determining path losses between the wireless station of unknown location and at least some of the access points. In the case the wireless station is a client station, the determining includes receiving measurements from the wireless station of unknown location measuring the received signal strengths as a result of respective transmissions from at least some of the access points at known respective transmit powers.
Type:
Grant
Filed:
November 7, 2005
Date of Patent:
December 13, 2011
Assignee:
Cisco Technology, Inc.
Inventors:
Daryl A. Kaiser, Kirshnam Raju V. Datla
Abstract: Estimating a current location of a receiver in a MediaFLO™ (Forward Link Only) mobile multimedia multicast system comprises receiving digital signals comprising a MediaFLO™ superframe comprising orthogonal frequency division multiplexing (OFDM) symbols; performing slot 3 processing of each medium access control (MAC) time unit of a data channel to identify a transmitter identity (TxID) of each transmitter; identifying corresponding geographical coordinates of each TxID; regenerating the digital signals for each of the transmitters using a local-area differentiator (LID) and a wide-area differentiator (WID) of the transmitters; dividing the digital signals by the corresponding regenerated transmitted signal to obtain channel estimates between the receiver and the corresponding transmitters; detecting a first peak in the channel estimates to determine a distance between the receiver and the corresponding transmitters; calculating a time difference of arrival of the digital signals; and estimating a current loca