Abstract: A LIDAR system, preferably including one or more: optical emitters, optical detectors, beam directors, and/or processing modules. A method of LIDAR system operation, preferably including: determining signals, outputting the signals, receiving one or more return signals, and/or analyzing the return signals.

Abstract: The carrier phase ready coherent acquisition of a global navigation satellite system (GNSS) snapshot signal includes receiving in a snapshot receiver different GNSS signals from correspondingly different GNSS satellites, and performing multi-hypothesis (MH) acquisition upon each of GNSS signal in order to produce a complete set of secondary code index hypotheses, each hypothesis producing a corresponding acquisition result according to an identified peak at a correct code-phase and Doppler frequency. The secondary code index hypotheses are adjusted for each different GNSS signal based upon a flight time difference determined for each GNSS satellite, so as to produce a new set of hypotheses. Finally, one of the hypotheses in the new set may be selected as a correct hypothesis according to a predominate common index amongst the hypotheses in the new set, and the acquisition results for each of the different GNSS signals may be filtered utilizing the correct hypothesis.

Abstract: Methods for tracking a signal origin by a spectrum analysis and management device are disclosed. Signal characteristics of other known emitters are used for obtaining a position of an emitter of a signal of interest. In one embodiment, frequency difference of arrival technique is implemented. In another embodiment, time difference of arrival technique is implemented.

Abstract: A wireless base station (such as disposed in a building) synchronizes itself with each of multiple reference stations in a network environment that transmit wireless signals. The wireless base station receives the wireless signals from the multiple reference stations. Based on timing of the received wireless signals, the wireless base station determines its location in a building with respect to the multiple reference stations. The determined location is then used as a basis to notify an allocation management resource of a location of the wireless base station for allocation of one or more wireless channels.

Abstract: This document describes techniques, apparatuses, and systems utilizing joint cost estimation for associating a detection-tracklet pair to an object. In aspects, a radar system generates a detection-tracklet pair that includes detection information about a detection for a radar reflection point in addition to tracklet information about a tracklet associated with the detection. Using the detection information and the tracklet information of the detection-tracklet pair, the radar system generates, for each potential data object of a plurality of potential data objects, a respective joint cost estimation and selects, based on the respective joint cost estimations, a data object from the plurality of potential data objects to associate with the detection-tracklet pair. The radar system then associates the detection-tracklet pair with the selected data object.

Abstract: Disclosed is an approach for automatic detection of entrance(s). In particular, processor(s) could have access to counter data arranged to maintain counters that each respectively represent a count of how many times GNSS service has been obtained or lost in a respective one of a plurality of sub-areas. Given this, the processor(s) could detect a GNSS state change corresponding to an instance of GNSS service being obtained or lost in a particular sub-area and could responsively increment the respective counter associated with the particular sub-area. In turn, the processor(s) could make a determination that the respective counter is representing a count that is greater than other count(s) represented by counter(s) associated with other sub-area(s). And based at least on this determination, the processor(s) could deem the particular sub-area to include an entrance, thereby resulting in detection of the entrance.

Abstract: A circuit includes a first wireless radio frequency (RF) transceiver and a time-of-flight estimator included with or coupled to the first wireless RF transceiver. The time-of-flight estimator estimates a time-of-flight between the first wireless RF transceiver and a second wireless RF transceiver using: a first interval value that indicates an amount of time between when the second wireless RF transceiver received the message and when the second wireless RF transceiver transmitted the response; a first error value that indicates an offset between when the second wireless RF transceiver sampled the message and a target sampling point for the message; a second interval value that indicates an amount of time between when the TX chain sent the message and when the RX chain received the response; and a second error value that indicates an offset between when the RX chain sampled the response and a target sampling point for the response.

Abstract: Methods for tracking a signal origin by a spectrum analysis and management device are disclosed. Signal characteristics of other known emitters are used for obtaining a position of an emitter of a signal of interest. In one embodiment, frequency difference of arrival technique is implemented. In another embodiment, time difference of arrival technique is implemented.

Abstract: Methods for tracking a signal origin by a spectrum analysis and management device are disclosed. Signal characteristics of other known emitters are used for obtaining a position of an emitter of a signal of interest. In one embodiment, frequency difference of arrival technique is implemented. In another embodiment, time difference of arrival technique is implemented.

Abstract: The present invention sequentially and repeatedly accepts a plurality of types of information that can change with time, including position information obtained using a satellite signal, and correlates and records the accepted plurality of types of information with time information.

Abstract: A receiver and method thereof are provided for synchronizing with a global navigation satellite system (GNSS) including a plurality of satellite vehicles (SVs). The method includes starting a verification process and a bitsync (BS) process in parallel with a first SV among the plurality of SVs, and upon completing the verification process while still performing the BS process, starting a track channel process with the first SV based on an interim BS result obtained at the time of completing the verification process, and starting a frame sync (FS) process with first SV based on the interim BS result. An aligned acquisition (AA) process may be started with a second SV among the plurality of SVs, upon completing the verification process, based on the interim BS result.

Abstract: Examples relate to communicating synchronization information from a satellite to a power supply device to enable time synchronization between the satellite and the power supply device. The power supply device includes a port to receive, from a modulator, a modulated current corresponding to a power consumption across a dummy load, where a level pattern of the modulated current indicates the synchronization information received from the satellite. The power supply device includes a power consumption analyzer configured to receive a modulated voltage, across a shunt resistor, corresponding to the modulated current and recover, from the modulated voltage, the synchronization information.

Abstract: A wireless communication system has at least one user-side-device and a base-station. The at least one user-side-device and the base-station are configured to communicate with each other via a satellite applying a timing-advance-value (TA) for synchronizing an uplink of the communication. The base-station is configured to provide the at least one user-side-device with a satellite-connecting-signal concerning an uplink towards the satellite, the satellite-connecting-signal providing configuration information in order to establish and adjust the uplink to the satellite. The at least one user-side-device is configured to perform an adjustment of the timing-advance-value for a pre-compensation of at least one synchronization offset of an uplink in case the at least one user-side-device receives the satellite-connecting-signal, the satellite-connecting-signal including a granting-signal indicating the user-side-device the allowance to adjust the timing-advance-value.

Abstract: The invention provides a method and an architecture for deploying non-terrestrial cellular network base stations, so as to enable cellular network coverage in remote areas, where no fixed infrastructure is available. The proposed methods allow for efficient power management at the terminal devices that need to synchronize to the airborne or spaceborne cellular base stations. This is particularly important for IoT devices, which have inherently limited power are computing resources.

Abstract: A method of processing signal paths includes receiving an estimated location for a GNSS receiver in an environment. The method also includes generating a plurality of candidate positions about the estimated location where each candidate position corresponds to a possible actual location of the GNSS receiver. The method further includes, for each available satellite at each candidate position, modeling a plurality of candidate signal paths by ray-launching a raster map of geographical data. Here, the plurality of candidate signal paths includes one or more reflected signal paths. At each candidate position, the method also includes comparing, the plurality of candidate signal paths modeled for each available satellite at the respective candidate position to measured GNSS signal data from the GNSS receiver and generating a likelihood that the respective candidate position includes the actual location of the GNSS receiver based on the comparison.

Abstract: A tracking method, an electronic device using the same, and a tracking system using the same are provided. The electronic device includes a wireless communication unit, an azimuth detection unit, a storage unit, and a processing unit. The wireless communication unit detects an external wireless communication signal to generate a current RSSI. The azimuth detection unit detects a current azimuth of the electronic device. The storage unit stores pattern strength indicators and a previous azimuth. The processing unit obtains an RSSI adjustment value according to the current azimuth, the previous azimuth, and the pattern strength indicators, and the processing unit further obtains an RSSI corrected value according to the RSSI adjustment value and the current RSSI.

Abstract: A receiver for null steering in a navigation or positioning system includes a controlled reception pattern antenna (CRPA) comprising elements, a switch array coupled to the elements of the CRPA, and a receiver circuit. The receiver circuit is configured to receive an incoming radio frequency (RF) satellite signal from the switch array. The receiver circuit is configured to control the switch array to receive digitized samples, wherein each sample is in a respective time interval for each element of the CRPA elements. The receiver circuit is configured to apply a weight value to each sample and sum the samples to provide a null steering beam.

Abstract: A satellite radio wave receiving device including: one or more controllers configured to: continually perform calculation of a current location based on radio waves from positioning satellites received by a receiver; determine whether an action state of the satellite radio wave receiving device detected by an action detection sensor has changed to a stop state; in response to determining that the action state of the satellite radio wave receiving device has changed to the stop state, interrupt the calculation of the current location by causing the receiver to interrupt reception of the radio waves; and cause an output device to perform an interruption notification operation for notifying that the calculation of the current location is being interrupted.

Abstract: A satellite signal receiving circuit includes an oscillator, two mixers, two phase shifters, two low-pass filters, two phase operation circuits, and a bandpass filter. When the frequency of the oscillator is between the center frequencies of the Global Orbiting Navigation Satellite System (GLONASS) and the GPS or the Galileo system, the GLONASS and GPS/Galileo satellite baseband signals are obtained through phase addition and subtraction performed by the phase operation circuits, while the BeiDou Navigation Satellite System (BDS) baseband signal is obtained through the bandpass filter. When the frequency of the oscillator is between the center frequencies of the BDS and the GPS or the Galileo system, the BDS and GPS/Galileo satellite baseband signals are obtained through phase addition and subtraction performed by the phase operation circuits, while the GLONASS satellite baseband signal is obtained through the bandpass filter.

Abstract: Systems and methods for determining a timing offset of a plurality of emitter antennas in a wireless network. The methods include deploying a network synchronization calibration unit at a location within receiving range of a plurality of direct path reference signals transmitted by the plurality of emitter antennas. The synchronization calibration unit receives the plurality of direct path reference signals and one or more reflected reference signals, which are then separated from one another to identify the direct path reference signals when a signal strength of one direct path reference signal is less than a signal strength of a reflected reference signal. A set of data is collected from the reflected reference signals that is indicative of the timing offset and that set of data is analyzed to estimate the timing offset.

Abstract: A method and devices are disclosed that increase the range of active geo-location from the airborne measuring station as compared with known methods by increasing the effective receive sensitivity of the airborne measuring station. In one embodiment this may be accomplished by transmitting a predetermined ranging packet and correlating the raw received bit stream of the response packet with the predetermined bit stream. In one embodiment, the disclosed method applies to the reception of IEEE 802.11 direct sequence spread spectrum DSSS ACK and DSSS CTS packets in response to DSSS data null and DSSS RTS packets respectively, in the 2.4 GHz band.

Abstract: A receiver device includes an acquisition engine and a reconfiguration engine. The acquisition engine uses a first circuit size. The acquisition engine is configured to receive a first signal including a plurality of first satellite vehicle signals, and identify a first satellite vehicle based on the first signal. The reconfiguration engine is configured to receive an indication that the acquisition engine identified the first satellite vehicle, and responsive to receiving the indication, generate a reconfiguration file defining a second circuit size less than the first circuit size. The reconfiguration engine is configured to cause the acquisition engine to be reconfigured based on the reconfiguration file to use the second circuit size.

Abstract: A timing signal output device includes a receiver configured to output a reference signal on the basis of satellite signals received from a plurality of positioning satellites, an oscillator configured to output a clock signal, and a processor configured to switch, on the basis of statistical value information concerning a statistical value obtained by performing statistical processing of elevation angles of the plurality of positioning satellites, a first mode for generating a timing signal based on the reference signal and a second mode for generating a timing signal based on the clock signal.

Abstract: GNSS receiver duty cycling is based on context awareness. Context awareness can be received signal quality, targeted navigation performance, and external information extracted from other sensors or being received from other sources such as cellular system, Wi-Fi, camera, LiDAR, and Bluetooth Low Energy (BLE).

Abstract: An information system for an industrial vehicle comprises an electronic component on the industrial vehicle that is programmably configured to obtain data by communicating across a vehicle network bus of the industrial vehicle with at least one other component of the industrial vehicle. The information system also comprises memory that stores industrial vehicle information according to a mapping specified by a data object model. Moreover, a processor on the industrial vehicle is programmed to repeatedly perform a cyclically recurring operation that extracts at least a portion of the industrial vehicle information stored in the memory device as broadcast information, generates at least one broadcast message representing the extracted broadcast information, and transmits the generated at least one broadcast message on the vehicle network bus. Accordingly, the entire contents of the broadcast information are repeatedly transmitted across the vehicle network bus in a cyclically recurring manner.

Abstract: An electronic timepiece, including: a counter; a display section; a first processor; a second processor; and a power supply section which supplies electric power to each section from a battery, wherein when an output voltage from the power supply section decreases to less than a predetermined first reference voltage, the first processor stops a display operation by the display section, when the time information is acquired by the processing operation of the second processor, the first processor corrects the time counted by the counter based on the acquired time information and causes the display section to display the corrected time, and when the output voltage decreases to less than the first reference voltage following an acquisition operation of the time information by the second processor, the first processor does not stop a time display operation during a predetermined pending period.

Abstract: A system and methods for location authentication are presented. An estimated server signal is estimated based on a generated known code signal, and a client received satellite signal is received from a client device. The client received satellite signal is compared to the estimated server signal to provide a comparison result.

Abstract: Pilot-aided digital coherent reception of high-order QAM signal detection using a continuous short pilot preamble and subsequent pilot symbols that are periodically distributed with payload data resulting in low-complexity and fast-convergence signal detection for continuous mode coherent reception of high-order QAM signals. A digital signal processor is configured to demodulate a transmitted data stream from digital stream of measurements of light mixtures produced in a receiver for coherent optical communications in response to receiving modulated optical carriers. The digital signal processor includes one circuit stage for providing corrections to the digital stream to compensate first effects on the light mixtures due to a frequency shift of a local optical oscillator of the receiver and another circuit stage for correcting the digital stream to compensate for second effects on the light mixtures due to polarization dependent channel modification of the modulated optical carriers.

Abstract: To provide a device for radio communication using a plurality of antennas, in which: an amplitude/phase adjuster (1) and an amplitude/phase controller (1) control the amplitude and the phase of signals input from at least two antennas such that a directivity, allowing a desired signal to be obtained; an amplitude/phase adjuster (2) and an amplitude/phase controller (2) control the amplitude and the phase of the signals input from the antennas such that an arrival direction of the desired signal becomes a null point and that a directivity, allowing a signal other than the desired signal to be obtained; a signal synthesizer (1) combines the signals; a signal synthesizer (2) combines the signals; and a desired signal generator removes a signal from the signal synthesizer (2) from a signal from the signal synthesizer (1).

Abstract: Methods for tracking a signal origin by a spectrum analysis and management device are disclosed. Signal characteristics of other known emitters are used for obtaining a position of an emitter of a signal of interest. In one embodiment, frequency difference of arrival technique is implemented. In another embodiment, time difference of arrival technique is implemented.

Abstract: A global navigation satellite system (GNSS) receiver including a sequential chip mixed frequency correlator array system (SCMFCAS) is provided. The SCMFCAS includes P signal generators, each receiving N samples of intermediate frequency (IF) data of a GNSS signal. Each signal generator includes a primary mixer, a pseudo random noise code generator, and Q mixed frequency correlators (MFCs). Each MFC generates accumulated correlation components of the N samples of the IF data by processing the N samples of the IF data. Adders and subtractors operably connected to the SCMFCAS are time division multiplexed for generating correlation values of a positive frequency and a negative frequency of the N samples of the IF data by combining the accumulated correlation components. Time division multiplexing the adders and the subtractors across the SCMFCAS and generation of the correlation values reduce logic area of the SCMFCAS, thereby reducing power consumption of the GNSS receiver.

Abstract: A method and a system for reducing time to first fix (TTFF) in a satellite navigation receiver generate a navigation data structure including three sub-frames. A first sub-frame and a second sub-frame accommodate selective ephemeris data. The third sub-frame accommodates a text message including almanac data optionally, ionospheric data, coordinated universal time (UTC) data, textual data optionally, and any combination thereof. A signal generation system (SGS) in the system selectively groups the almanac data, the ionospheric data, and the UTC data, and selectively transmits the navigation data with the almanac data or free of the almanac data in the navigation data structure to the satellite navigation receiver. The signal generation system also staggers the navigation data in each sub-frame into a first portion and a second portion for parallelly transmitting the navigation data over a first carrier frequency and a second carrier frequency in reduced time.

Abstract: This determination method for determining a wrong synchronization including the steps of determining an ad hoc correlator corresponding to the value of correlation between the received signal and the local signal, and determining N additional correlators corresponding to the values of correlation between the received signal and an offset signal, each offset signal including a spreading code that is offset in relation to the local spreading code, and determining a value for the amount of inconsistency between the frequency of the local carrier wave and the frequency of the local spreading code; if the value of inconsistency is higher than a predetermined threshold value of inconsistency, determining a wrong synchronization; otherwise, determining an indicator of wrong synchronization as a function of the correlators determined, comparing the indicator of wrong synchronization with at least one threshold value, determining a wrong synchronization based on the result of the comparison.

Abstract: Exemplary systems and methods can be provided for measuring a parameter—e.g., channel impulse response and/or power delay profile—of a wideband, millimeter-wave (mmW) channel. The exemplary systems can include a receiver configured to receive a first signal from the channel, generate a second signal, and measure the parameter based on a comparison between the first and second signals; and a controller configured to determine first and second calibration of the system before and after measuring the parameter, and determine a correction for the parameter measurement based on the first and second calibrations. Exemplary methods can also be provided for calibrating a system for measuring the channel parameter. Such methods can be utilized for systems in which the TX and RX devices share a common frequency source and for systems in which the TX and RX devices have individual frequency sources that free-run during channel measurements.

Abstract: A method and a system for reducing time to first fix (TTFF) in a satellite navigation receiver generate a navigation data structure including three sub-frames. A first sub-frame and a second sub-frame accommodate selective ephemeris data. The third sub-frame accommodates a text message including almanac data optionally, ionospheric data, coordinated universal time (UTC) data, textual data optionally, and any combination thereof. A signal generation system (SGS) in the system selectively groups the almanac data, the ionospheric data, and the UTC data, and selectively transmits the navigation data with the almanac data or free of the almanac data in the navigation data structure to the satellite navigation receiver. The signal generation system also staggers the navigation data in each sub-frame into a first portion and a second portion for parallelly transmitting the navigation data over a first carrier frequency and a second carrier frequency in reduced time.

Abstract: The present invention relates to a communication node arrangement comprising at least two antenna units. Each antenna unit comprises at least one signal port and at least one antenna element, where each signal port is connected to at least one corresponding antenna element. Each antenna unit comprises at least one sensor unit arranged to sense its orientation relative a predetermined reference extension. The communication node arrangement comprises at least one control unit and is arranged to feed a respective test signal into each of at least two different signal ports. For each such test signal, the communication node arrangement is arranged to receive the test signal via at least one other signal port. The communication node arrangement being arranged to determine relative positions of said antenna units based on the received test signals, and to determine relative orientations of said antenna units based on data received from the sensor units.

Abstract: Asynchronous Global Positioning System (GPS) baseband processor architectures with a focus on minimizing power consumption. All subsystems run at their natural frequency without clocking and all signal processing is done on-the-fly.

Abstract: Industrial vehicles communicate across a wireless environment and the wireless communication, data collection and/or processing capabilities of industrial vehicles are leveraged against robust software solutions to implement enterprise wide vehicle management functions, to integrate industrial vehicle data into existing enterprise workflows and/or to enable trusted third party integration into the enterprise for enhanced asset and/or workflow management. Still further, wireless communication, data collection and/or processing capabilities of industrial vehicles are leveraged with robust software solutions that aggregate and analyze data across multiple enterprises and/or promote the exchange of information between independent entities.

Abstract: The present invention relates to a method for improving Time To First Fix, TTFF, sensitivity and accuracy, wherein a Global Navigation Satellite System, GNSS, positioning device (15), communicates with a Core Service (11) in a User Equipment (16), U—the GNSS positioning device acquires (23) GNSS satellite signals and navigation data and based on said signals/data determines a position within TTFF,—the Core Service detects (24) user data indicating specific user behaviors and initiates said determination of position based on said user data. The present invention also relates to a Core Service, a Global Navigation Satellite System, GNSS, positioning device, a Radio Module and a User Equipment, UE, adapted for the same purpose.

Abstract: An electronic timepiece comprises a receiver configured to receive satellite signals containing time information from positioning information satellites; an interface member; a timekeeping reception controller configured to execute a timekeeping reception process in response to a timekeeping reception operation of the interface member; and a positioning reception controller configured to execute a positioning reception process in response to a positioning reception operation of the interface member. The timekeeping reception controller starts the timekeeping reception process if the interface member is operated continuously for a first set time, and continues the timekeeping reception process if operation of the interface member is released before a second set time passes, the second set time being longer than the first set time, and operation switches from the timekeeping reception process to the positioning reception process if the interface member is operated for the second set time.

Abstract: According to the invention, a data stream with continuous, periodic transmitted, spread data signals of N chips each is split into two data streams of N chips each, which are shifted by N chips; for each of these data streams the correlation functions are calculated within every chip clock time and, in relation to their maxima, evaluated in order to separate user signals from extraneous signals and disturbing signals.

Abstract: A timepiece can acquire time information in a short time, reduce power consumption, and display the correct time. A timepiece comprises a receiver to receive a satellite signal, and a time information generator to generate internal time information. The receiver runs a first reception process that acquires first information including week information from the satellite signal, a second reception process that acquires second information including leap second information from the satellite signal, or a third reception process that acquires third information including hour, minute and second information from the satellite signal. In the first reception timing, after the internal time information is initialized, the receiver runs the first reception process and runs the second reception process after running the first. In a next reception timing, after the first reception timing, the receiver runs the third reception process if the first and second information are acquired in the first reception timing.

Abstract: A continual learning process is applied to a class of risk estimate-based algorithms and associated risk thresholds used for deciding when to initiate a handoff between different types of network connections that are available to a mobile device having telephony functionality. The process is implemented as a virtuous loop providing ongoing tuning and adjustment to improve call handoff algorithms and risk thresholds so that handoffs can be performed with the goals of minimizing dropped calls and unacceptable degradation in call quality as well as avoiding premature handoffs. Device characteristics, environmental context, connection measurements, and outcomes of call handoff decisions are crowd-sourced from a population of mobile devices into a cloud-based handoff decision enabling service.

Abstract: A method and an apparatus for setting a working mode of power amplifier (PA) blanking are disclosed, which resolve a problem that, in the prior art, when a Global System for Mobile Communications (GSM) is working, because a PA blanking function cannot be configured flexibly to an enabled state or a disabled state, quality of a Global Positioning System (GPS) receiving signal is degraded. When a GPS is running, it is detected, at a preset interval, whether a GSM service is running. When the GSM service is running, a current quantity of timeslots occupied by the GSM service and a current power control level used by the GSM service are acquired.

Abstract: A frequency synthesizer in a GNSS receiver chip enables duty cycling operation of the frequency synthesizer. The frequency synthesizer is cycled on to generate required clock signals for the GNSS receiver chip, and cycled off during a measurement duty cycle comprising measurement available intervals and measurement unavailable intervals. A reference clock inputted to the frequency synthesizer is on during the measurement duty-cycle. During the measurement available intervals, the frequency synthesizer is cycled on to generate the required clock based on the reference clock. During the measurement unavailable intervals, the frequency synthesizer is cycled off and clock timing is maintained based on the reference clock. A number of elapsed clock cycles of the reference clock is captured for a measurement unavailable interval and transferred to a clock offset. The GNSS receiver chip processes signals received using the required clock and the clock offset in a following measurement available interval.

Abstract: A method of acquiring a satellite signal includes providing a CDMA-modulated signal, defining a first search frequency interval and a first reception sensitivity, and performing a first acquisition of the modulated signal according to the first sensitivity and the first frequency interval in order to provide an acquisition or failed acquisition result. In case of a failed acquisition, performing a second acquisition of the modulated signal as a function of a second search frequency interval, narrower than the first frequency interval, and a second reception sensitivity, greater than the first sensitivity and depending on a power of a side lobe of the modulated signal.

Abstract: A GPS wristwatch has a reception mode setting unit that sets a reception mode of a reception unit; and a locking level setting unit that sets a locking performance. The reception mode setting unit sets the reception mode to an automated timekeeping mode when an automated reception condition is met; sets the reception mode to a manual timekeeping mode when a first operation of an input unit is detected; and sets the reception mode to a positioning mode when a second operation of the input unit is detected. The locking level setting unit sets the locking performance to a high level when the reception mode is set to the manual timekeeping mode or the positioning mode, and sets the locking performance to a low level that is lower than the high level when the reception mode is set to the automated timekeeping mode.

Abstract: A satellite-based positioning system (SPS) signal processing technique re-samples a received series of PRN sequences from an SPS satellite to align them with a nominal sampling rate for a corresponding series of perfect reference PRN replica sequences.

Abstract: A system and methods for reducing navigation satellite receiver power usage are presented. A wireless signal is received at a portable electronic device in a signal environment. At signal characteristic of the wireless signal at the portable electronic device is measured in the signal environment. An estimated signal strength of the wireless signal in the signal environment is estimated based on the signal characteristic. The estimated signal strength is compared to an expected signal strength of the wireless signal to calculate an estimated signal-strength-change relative to the expected signal strength. A GNSS signal is tracked at the portable electronic device, if the estimated signal-strength-change indicates an expected GNSS signal attenuation is lower than a signal attenuation threshold.

Abstract: In a satellite radio-controlled wristwatch, a time to be spent on acquisition and tracking is reduced and also a reception success probability is increased.