Abstract: Systems and methods for allowing the location of transmitter to be determined (approximated) without requiring its distance from a receiver to be precisely known. Methods for determining a location of a transmitter without precise distance calculations. In one embodiment, a method is disclosed having the steps of: for a receiver, estimate a first zone a first transmitter is in; for remaining receivers that can receive a given transmitter, each estimate a second zone a first transmitter is in; and determine if there are overlaps in any of the zones. In another embodiment a potential target area is defined wherein the location of a transmitter can estimated.

Abstract: A method for determining a location of a digital radio transmitter includes detecting, by at least three spatially separated receivers, a digitally encoded radio signal, having a known pattern of bit transitions, radiated from the transmitter. Once detected, a time of arrival of the bit transitions at each of the receivers is determined. Then, an indication of the time of arrival at each respective receiver for the bit transitions is transmitted from each of the receivers to a central processor. At the central processor, time of arrival differences of common bit transitions among the receivers are determined. Based on the time of arrival differences, the central processor may calculate the location of the transmitter.

Abstract: A system for indicating race position to spectators of a race, includes lights on the race participants that are configured to provide visual displays to the spectators indicating the position of the respective racer. The race participants also carry a receiver and a controller for receiving a signal indicating race position and selecting the appropriate visual display based on the received signal. The visual display can be a series of lights, such as linear arrays of LEDs, where the color, number, pattern and/or position of the lights indicates race position. The system can also be used to highlight selected racers of interest, for example in conjunction with information being relayed over the public address system of the racetrack.

Abstract: The invention relates to a method for determining transmission times of signals transmitted by at least one radio transmitter BTS. In order to enhance the accuracy and reliability of estimates of transmission times or of changes of the transmission time of signals transmitted by radio transmitters BTS, it is proposed that a difference in the time level of estimates of the transmission times based on the measurement results of two different radio receivers LMU A,B is taken into account in a filtering of the estimates for obtaining an accurate value for the transmission times. It is further proposed that the changes of the transmission times estimated at different receivers LMU A,B is averaged for obtaining an accurate information about the changes. The invention equally relates to a corresponding radio communications system and to a processing unit for such a system.

Abstract: The present invention is directed to a method for locating a mobile station, comprising the steps of using fixed transmitting stations for locating a target mobile station by transmitting a measurement signal from each fixed transmitting station to the mobile station, using a relay station which is adapted to receive the measurement signal from the corresponding fixed transmitting station and to forward the signal to the target mobile station, in case a direct transmission from one or more of the fixed transmitting stations is not available, and determining the distance between the target mobile station to the fixed transmitting stations and/or the relay stations on the basis of the measurement signal, and locating the position of the target mobile station on the basis of the determined distances. By this method, it is possible to locate a mobile station even if there is no direct connection via air to neighbouring base stations.

Abstract: A location discovery method using location data items that originate at known locations (X,Y) and are passed to, and diffused between, entities (A,B) by short-range communication. Each location data item received by an entity (A,B) indicates a maximum distance of the entity from one of the known locations (X,Y). Each entity (A,B) prior to using a location data item for location determination or transferring it to another entity, is operative to increase the maximum distance indicated by the location data item to take account of movement of the mobile entity since receiving that item. A mobile entity (A) effects location determination by finding locations (40) simultaneously consistent with the maximum distances (31,36) it knows of and any applicable route constraints for how the location data items passed to the mobile entity.

Abstract: In the case where variations in ground objects in one and the same area are detected between a line drawing map describing profile lines of the ground objects or a reference line drawing/image obtained by picking up the ground objects from above, and a target image obtained by picking up the ground objects in the same area from above later on, a variation detecting apparatus collates the reference line drawing/image with the target image so as to obtain variation indexes indicating whether there are variations or not in the ground objects respectively, and displays ground objects which can be judged to have variations or ground objects which cannot be judged as to whether there are variations or not on the basis of the variation indexes, in a display mode in which an area of the reference line drawing/image including the ground objects and an area of the target image including the ground objects can be compared with each other.

Abstract: Cell coordinates available in the radio network is used to determine an area where the mobile radio is located and does not rely upon mobile radio measurements. Such cell coordinates for cells currently associated with the mobile radio are used by the radio network to determine a location of the mobile radio. Those current cells may include cells that are candidates for supporting a communication with the mobile radio, an active set of cells, cells that are currently supporting communication with the mobile radio, or some other set of cells geographically associated with the mobile radio.

Abstract: A multiple pass location processing method, for use in a wireless location system (WLS), comprises identifying a received transmission as requiring multiple pass location processing whereby the WLS produces a first, lower quality location estimate and then subsequently produces a second, higher quality location estimate. The WLS then produces the first location estimate and provides it to a first location application, and then produces the second location estimate. The second location estimate may be a more accurate estimate than the first location estimate and/or of a higher confidence than the first location estimate. This method is suitable, but not limited, for use in connection with locating a wireless transmitter involved in an emergency services call and routing the call to a call center.

Abstract: A system for automatic collection of tolls includes an in-vehicle toll processor having memory for storing a toll-money-available quantity purchased by the user, and a toll-facility-identification site that transmits a toll-facility-identifier signal indicating the identity of the upcoming toll facility. As the vehicle approaches the identification site, the in-vehicle processor receives the identifier signal and calculates the toll to be debited. When the vehicle passes through the toll facility, the in-vehicle processor transmits its identity, its net balance and the toll, which it debits from an account balance. The in-vehicle processor may increment a low balance, in which case it transmits information which is relayed to a central system for billing. Various means for shutting down delinquent in-vehicle components or identifying offender vehicles are described.

Abstract: A tracking device for tracking a vehicle in which a radio transmitter is powered by heat energy of the exhaust system of an engine propelling the vehicle. A thermoelectric module is attached to a hot portion of the exhaust system. Electrical power generated by the thermoelectric module is used to power the transmitter. A preferred tracking device consists of one thermoelectric module, one transmitter, a flexible finned plate for dissipating heat, and two high Curie temperature magnets for attaching the device to the vehicle's tail pipe. The transmitter is mounted on the flexible finned plate with a thermal insulator in-between them.

Abstract: A system for determining the position of a transponder transmitting a signal and moving along a route is disclosed. The route includes a measuring station with at least two measuring points having on each side of the route and along a line generally perpendicular to the route. The measuring station includes a first receiver that receives the signal at one measuring point and a second receiver that receives the signal at the other measuring point. Each receiver provides an output. A circuit measures the phase difference between the outputs of the first and second receivers, and the transponder location along the line between the measuring points is determined based on the measured phase difference.

Abstract: Systems and methods for comparing data quality for multiple wireless communication networks are provided. One such method comprises: obtaining information related to a location of a first mobile wireless device associated with the first wireless data network and a second mobile wireless device associated wish the second wireless data network; establishing a first data call between the first mobile wireless device and the first wireless data network and a second data call between the second mobile wireless device and the second wireless data network, the first and second data calls based on a predefined testing scenario; obtaining information related to the quality of data service associated with the first and second data calls; and correlating the information related to the quality of data service associated with the first and second data calls with the information related to the location of the first and second mobile wireless devices.

Abstract: A method and system for determining the three-dimensional location of a mobile wireless device. In one implementation, the device is a cellular telephone making a 911 call from one floor of a multi-story building. An embodiment of the method of the invention includes establishing a database that associates transmission metrics with altitudes of x-y coordinate locations having more than one altitude at which the mobile wireless device could be located, receiving a communication from the mobile wireless device, determining an x-y coordinate location of the mobile wireless device, measuring a transmission metric of the mobile wireless device, and consulting the database to determine the altitude from the x-y coordinate location and the measured transmission metric. The transmission metric could be, for example, the transmission time or angle of arrival of a wireless signal received from the mobile wireless device.

Abstract: A radio system employing Orthogonal Frequency Division Multiplexed (OFDM) includes a Base Transceiver Station (BTS) along with a number of mobile terminals located within a coverage area of the BTS. In this system, a target mobile terminal is provided with a focused transmission beam to receive high data rate traffic information while the remainder of the mobile terminals are provide with pilot and signalling information. To achieve both objectives, a BTS is implemented with a transmission apparatus that generates a directional transmission beam for the data traffic information. In one design, this directional beam transmits the pilot and signalling information along with the data traffic information by rotating the beam within the coverage area. In another design, the BTS has a transmission apparatus that generates more than one transmission beam.

Abstract: A system of the present invention is operative for locating a wireless mobile device in communication with a wireless local area network (WLAN) that includes a plurality of cells defining a wireless local area network each having an access point base station. The access point base stations communicate with wireless mobile devices using wireless communication signals as typically spread spectrum communication signals. A processor is operatively connected to each of the access point base stations and operative to process communication signals transmitted from a mobile device and determine which signals are first-to-arrive signals based on a common timing signal and conduct differentiation of the first-to-arrive signals to locate the mobile device.

Abstract: A method and apparatus for real time clock brownout detection. A low power real time clock (RTC) operates continuously to keep time in a global positioning system (GPS) receiver while some receiver components are powered down. In various embodiments, a brownout detector circuit detects a loss of RTC clock cycles. If a loss of RTC clock cycles exceeds a predetermined threshold such that the RTC is not reliable for GPS navigation, an RTC status signal so indicates.

Abstract: A method of measuring reception timings of signals transmitted and received between base stations and a mobile station and calculating the position of the mobile station by using the reception timings and the reception positions of the signals comprises the steps of obtaining the address information items necessary to specify incoming signals used for the position calculation, analyzing address information items included in the incoming signals, and selecting incoming signals used for position calculation according to a result of comparing the obtained address information items with address information items analyzed in accordance with the incoming signals. A signal incoming from a desired radio station is thus selected and used for position calculation.

Abstract: A method of locating a mobile telephone includes steps of receiving, transmitting, increasing and determining. In the receiving step, a first base station receives a call from a mobile telephone, the call including a dialed number and a TDMA signal. In the transmitting step, the base station transmits a control message to the mobile telephone when the dialed number meets a predetermined criterion, such as being 911. The control message instructs the mobile telephone to transmit the TDMA signal at a maximum power. In the increasing step, the mobile telephone increases the TDMA signal to maximum power in response to the control message. Then in the determining step, location information for the mobile telephone is determined based on at least one characteristic of the TDMA signal received at at least one of the first base station and other base stations.

Abstract: A method, apparatus, and computer-readable media comprise receiving a broadcast digital television signal comprising data relevant to one or more particular locations; generating a pseudorange based on the broadcast digital television signal; and determining location of an apparatus based on the pseudorange and a location of a transmitter of the broadcast digital television signal, and selecting a portion of the data relevant to the one or more particular locations based on the determined location of the apparatus.

Abstract: A computer program product, apparatus, and method for determining the position of a user terminal. It includes receiving, at the user terminal, a broadcast analog television signal having a periodic component; and correlating the broadcast analog television signal with a predetermined reference signal based on the periodic component, thereby producing a pseudorange; and wherein the location of the user terminal is determined based on the pseudorange and a location of the transmitter of the broadcast analog television signal.

Abstract: The present invention provides method and apparatus for facilitating base station selection/handover by a user terminal in a distributed (e.g., cellular-type) wireless communication system. In accordance with one aspect, hysteresis is adaptively determined as a function of the variance of receive signal strength fluctuations. In turn, an adaptive hysteresis factor can be obtained and used for a subsequent handover decision, for example, based on a cost function that takes into account the hysteresis. In accordance with another aspect, base station selection depends on a number of criteria, such as received signal strength, base station load, and estimated distance between a receiving user terminal and one or more base stations.

Abstract: A system and a method for controlling a vehicle remotely over a network are disclosed. A vehicle is provided with a vehicle control module configured to transmit and receive network communications containing vehicle control data. In one embodiment, the vehicle control module is configured to transmit and receive network switched packets wirelessly. Additionally, the vehicle may comprise one or more cameras configured to transmit a two dimensional, three dimensional, or 360° panoramic view from the vehicle. The network comprises a user station, a server, and at least one vehicle to be controlled. The user station may comprise an operator booth that resembles the driving compartment of a vehicle. Alternatively, the user station may comprise a portable control device.

Abstract: A location is disclosed for wireless telecommunication infrastructures. The systems output requested locations of hand sets or mobile stations (MS) based on, e.g., AMPS, NAMPS, CDMA or TDMA communication standards. The system determines both local MS locations, and more global MS location requests via, e.g., Internet communication. The system uses a plurality of mobile station locating technologies, including those based on, e.g., (1) two-way TOA and TDOA; (2) home base stations and (3) distributed antenna provisioning. The system is useful for 911 emergency calls, tracking, routing, people and animal location including applications for confinement to and exclusion from certain areas. The system is particularly useful for estimating a location of an MS using information received from a commercial mobile radio service provider (CMRS) for which the MS is not registered for subscriber services.

Abstract: An E-OTD method for locating a mobile station using measurement information related to arrival of signals transmitted from base stations of different operators for obtaining the base station locations. When one operator does not have enough base stations for providing measurement information for location calculation, the SMLC of that operator acquires measurement information of base stations from at least one other operator using SMLC-SLMC communication protocol.

Abstract: A wireless telecommunications network uses a wireless location technology to determine the locations of mobile stations. As part of a location accuracy analysis process, the wireless location technology is used to obtain a measured latitude and longitude for a mobile station located at a test site having a known latitude and longitude. A data analysis system calculates the radial location error, expressed as a distance, between the measured and known latitude and longitude values. The process is repeated a number of times sufficient to calculate the mean radial location error to within a predetermined uncertainty at a predetermined confidence level.

Abstract: The present invention relates to communication improvements between a mobile device (12) and backend system (20) applications. A special purpose server computer—a Device Registry Server (18)—is switched between a large variety of different mobile device types (12) and a plurality of backend systems (20) for improving the communication between a mobile device and a backend system. The server (18) stores information usable for facilitating communication setup, operation and maintenance of device applications. Preferably, a ready-to-use, already customized device-type specific application can be downloaded from said server (18) to a variety of different mobile devices which is then used for easily communicate with any desired backend system (20).

Abstract: A method and system for positioning mobile units using angle measurements taken by neighboring mobile units is disclosed. A selected mobile unit and mobile units in the vicinity of the selected mobile unit are selectively instructed to measure and report information related to the position of the selected mobile unit. The reported information is used to compute a position of the selected mobile unit.

Abstract: A real-time path-directed controller for navigating an object along a desired path is disclosed. The controller comprises: a position sensor which contributes to the production of a conditioned object position signal to a controller summer; a heading conditioning module which contributes to the production of a conditioned heading signal to the controller summer; a control apparatus sensor which contributes to the production of a conditioned control apparatus signal to the controller summer; and a control apparatus null position conditioning module which contributes to the production of a conditioned null position signal to the controller summer. The controller summer sums the signals to produce a controller summer signal to a controller summer conditioning module so as to produce a control apparatus control signal to a control apparatus controller so as to direct the control apparatus and thereby direct the object by feedback control along the desired path.

Abstract: An improved code acquisition scheme for faster acquisition of GPS “coarse acquisition” (C/A) codes leads to faster detection of GPS signals, and thereby a wireless terminal may determine its position in a shorter period of time. The scheme is a combination of a frequency-domain and time-domain code acquisition techniques. The scheme utilizes a frequency-domain code acquisition technique to detect one GPS signal and to create a precise timing reference at the wireless terminal, and then utilizes time-domain code acquisition techniques to detect other GPS signals from the same satellite or other satellites faster. The scheme has the advantage of being able to be used for any wireless communications system without the requirement of maintaining a precise timing reference in the wireless terminals, and without the requirement of heavy computational resources that are usually needed in systems that utilize frequency-domain code acquisition techniques.

Abstract: 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).

Abstract: A method and apparatus is disclosed for providing a range of location dependent information and services to users of wireless devices coupled to the multi-point wireless access network of the current invention. In an embodiment of the invention a multi-point wireless access network for servicing wireless devices is provided. The multi-point wireless access network includes: wireless access devices, an inventory map and a server. The wireless access points are arrayed in a coordinate system with a known relative relationship to one another. Each of the wireless access points provides communication capabilities for corresponding proximate ones of the wireless devices. The inventory map correlates selected ones of the wireless access points with corresponding inventory located proximate to each of the selected ones of the wireless access points.

Abstract: A user terminal comprises a receiver adapted to receive, at the user terminal, a broadcast digital television signal transmitted by a television transmitter and comprising a pseudo-noise code; and a controller adapted to generate a pseudorange based on the pseudo-noise code; wherein the location of the user terminal is determined based on the pseudorange and a location of the television transmitter.

Abstract: A vehicle locating system includes a first transmitter within the vehicle, the first transmitter is configured to transmit a location signal; and a key fob including: a receiver, a direction indicator, and wherein the direction indicator is configured to point towards the first transmitter in response to receipt of the location signal by the receiver.

Abstract: This invention relates to a radio base station equipment and a mobile station equipment in a mobile communication system that operate as determination stations adapted for a predetermined navigation or associate with other radio base station(s) or mobile station(s) to radio-determine the location of a desired mobile station. The mobile communication system achieves a radio determination economically and reliably while flexibly adapting itself to the substantial traffic distribution and transmission characteristics in individual wireless zones as well as the zone configuration, channel allocation, the procedure of channel control, and the structure of hardware.

Abstract: A method of controlling an Automatic Guided Vehicle (AGV) system having a plurality of AGVs includes setting a moving path with task times of all the AGVs taken into account, and controlling the AGVs according to the set moving path. The setting the moving path includes calculating respective costs required for the AGVs to perform a plurality of tasks and calculating a number of cases occurring by allocation of each of the tasks to the AGVs. The setting the moving path also includes calculating respective total costs required for the AGVs to perform a corresponding task or corresponding tasks for all of the cases, determining a smallest and largest value out of the respective total costs for each of the cases, and setting the moving path of the AGVs according to the case having the smallest value.

Abstract: The invention relates to a locating device for remote location of an object, and a method for operating the locating device, particularly with a view to recovering objects which are stolen. The locating device comprises a mobile communication unit which is placed together with the object. Data concerning the communication unit's position are determined and registered by means of the existing infrastructure in a cellular network of which the communication unit forms a part when it is activated. The communication unit can be activated to a standby mode and deactivated to a sleep mode. The invention is characterized in that the communication unit is activated and deactivated depending on a time-variable signal generated in the locating device, thus providing a reduction in the communication unit's average power consumption. The signal is preferably derived from the locating device's acceleration.

Abstract: Methods and systems for providing mobile subscriber surveillance identify certain call signaling messages as candidate messages for mobile subscriber surveillance. From the candidate messages, messages associated with mobile subscribers under surveillance are identified. Mobile subscriber location information is obtained for the messages associated with the mobile subscribers under surveillance. The location information is forwarded to a surveillance center, such as a state or federal law enforcement or security agency. The original call signaling messages are forwarded to their intended destinations so that surveillance is performed transparently to the mobile subscriber under surveillance.

Abstract: The present invention provides a system for automatically registering destination of visit or a normally stationed spot to a mobile information system such as car navigation system. A position information detected by position detecting means 101 is stored in position storage means 102. From the position information or from pattern of moving loci stored in the position storage means 102, the position recognizing means 103 recognizes a place frequently visited or a normally stationed spot of the system, and these are registered automatically as registered destination or a normally stationed spot (owner's own home). Thus, the destination frequently visited can be registered without performing specific operation. The registered position can be used as a place of destination for searching a desirable route for the vehicle. Also, by recognizing the normally stationed spot, theft can be detected.

Abstract: The invention relates to a telematics method for helicopters. According to the inventive method, the use spectrum of helicopters which are provided with all-weather flight guidance and obstacle warning systems is enlarged and flight security is further improved by transmitting data and/or speech by means of terrestrial and/or satellite-supported mobile radio telecommunications networks and by connecting to a locating system. Logistics processes of the helicopter operation and of the institutions benefiting from a helicopter use are optimized.

Abstract: A method of providing a vehicle monitoring system for ensuring accurate vehicle milleage readings. A comparison is made between velocity measurements from several sources to detect unauthorized modifications made to a vehicle in an effort to ensure accurate vehicle odometer readings. The vehicle velocity measured on-board is compared with vehicle velocity data signals received from a remote satellite system in light of an allowable tolerance. The system will detect changes in the vehicle such as tire size or tampering with the vehicles on-board measurement devices. The system may communicate out of tolerance conditions to the vehicle operator and the fleet manager.

Abstract: 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.

Abstract: A location-relevant service system provides location-relevant information to, or performs location-relevant service for, a first mobile unit based on the location of a second mobile unit. In one instance, the first mobile unit is fixed on a vehicle, while the second mobile unit can be provided as a cellular phone. In another instance, the first mobile unit is provided with a display panel, so that authentication can be achieved through providing the displayed location information to a location-relevant service server using the second mobile unit.

Abstract: A location management method manages the location of a member which move around carrying a GPS-equipped portable telephone. The method includes inquiring of the GPS-equipped portable telephone about its current location, making the GPS-equipped portable telephone return positional information of the current location measured by the GPS function, managing the returned positional information of the current location in a file, searching a map database based on the positional information of the current location, and preparing and displaying map data linked with the positional information of the current location.

Abstract: There is disclosed a guidance assisting apparatus for aiding in the guidance of an agricultural vehicle (5) over arable land. The apparatus makes use of a GPS positional receiver (81) in order to determine if the vehicle (5) is overlapping previous passes of a paddock thereby reducing the likelihood of strips of land being double processed or left unprocessed. Guidance may be provided by a visual display or by power assisted steering.

Abstract: A multiple pass location processing method, for use in a wireless location system (WLS), comprises identifying a received transmission as requiring multiple pass location processing whereby the WLS produces a first, lower quality location estimate and then subsequently produces a second, higher quality location estimate. The WLS then produces the first location estimate and provides it to a first location application, and then produces the second location estimate. The second location estimate may be a more accurate estimate than the first location estimate and/or of a higher confidence than the first location estimate. This method is suitable, but not limited, for use in connection with locating a wireless transmitter involved in an emergency services call and routing the call to a call center.

Abstract: A system and method of estimating the position of a mobile terminal (MT) operating in a radio telecommunications network. Expected Received Signal Strength (RSS) values are predicted by a computer-aided prediction tool, and/or are measured by a test MT from base station transceivers. The predicted and measured RSS values are then tagged to indicate whether each value was predicted or measured. The RSS values are then stored at a plurality of locations in a database. When RSS measurements are received from the MT being located, a covariance matrix is used to compute metrics for the locations in the database. If more than a threshold percentage of the locations were populated with measured values, a Maximum-Likelihood (ML) estimator is used to estimate the position of the MT. If fewer than the threshold percentage of locations were populated with measured values, a Minimum-Mean-Square-Error (MMSE) estimator is used to estimate the position.

Abstract: A positioning apparatus and method for accurately determining a current position of a mobile station. The current position of the mobile station is determined utilizing radio waves arriving from a plurality of base stations installed in a communication area. For calculating a propagation range of a radio wave arriving from each base station, error correction processing is performed using a predetermined error correction coefficient previously calculated by measuring a radio wave propagation situation around each base station to estimate a propagation range of a direct wave within incoming radio waves. The current position of the mobile station is determined using the estimated propagation range and the positions of the respective base station.

Abstract: A positioning system and a position calculating method in a mobile communication system for specifying a position of a mobile station unit on the basis of positional information from three base station units and for displaying related map information on the mobile station unit to utilize the positional information effectively, the position system and the position calculating method in which a position reporting means of a base station unit reports positional information, a distance difference calculating means of the mobile station unit calculates differences in distance between the mobile station unit and three base station units on the basis of the positional information from the three base station units, measures a position of the mobile station unit on the basis of the positional information and the distance differences by using a position measuring means, reports the measured position to an exchange unit by using a position reporting means, and a map information displaying means of the mobile station uni

Abstract: The invention relates to a method and to devices for determining in a positioning system the time of reception of a beacon signal which was received and tracked by a receiver. In order to enable a re-acquisition of the system time based on a noisy received signal, it is proposed that the method comprises as a first step reconstructing a beacon signal for an interval based on available information. Then, a cross-correlation is performed between the reconstructed signal and the received signal at different relative positions to each other. Next, the time of transmission of the received signal is determined based on information for the reconstructed signal and on the relative position resulting in the maximum correlation value. Finally, a time of reception of said received signal is determined as the sum of the determined time of transmission of the received signal and of a calculated time of flight of the received signal.