Abstract: It is provided of a system capable of estimating a current position of a terminal apparatus, even if a terminal apparatus for mobile communication is in a condition of non-receiving or inability to receive GNSS signals. A radio relay apparatus, in which a relay station mounted on a drone, transmits radio waves from a directional antenna toward the ground while flying in an upper airspace above a target area on the ground, and transmits position information on its own apparatus obtained based on the GNSS signal, to an information processing apparatus. The terminal apparatus measures a reception power or a reception quality of radio waves transmitted from the radio relay apparatus, and transmits reception measurement information regarding the measurement result of the reception power or the reception quality, to the information processing apparatus.

Abstract: Embodiments provide for methods and portable positioning devices adapted to determine a geospatial position of a point of interest. In one embodiment, the portable positioning device comprises an antenna, a levelling detector, an imaging device, a display unit and a processing unit. The antenna may be adapted to receive satellite information signals. The levelling detector is arranged relative to the antenna for detecting whether the antenna is positioned horizontally. The imaging device has an optical axis and a sighting axis. In one embodiment, the sighting axis intersects an antenna axis. In another embodiment, the sighting axis is aligned with the antenna axis. The display unit may be provided for assisting in identifying the point of interest within a field of view of the imaging device and for assisting in identifying whether the antenna is horizontally levelled and whether a phase center and the point of interest are vertically aligned.

Abstract: A method for immersively displaying a scanned environment of a region to a set of users in a training environment wearing augmented reality head display units. The training environment includes a pseudo-GPS system, which allows position tracking over time. This enables rehearsing military operations before they occur.

Abstract: Embodiments are disclosed for localization of vehicles using beacons. In an embodiment, a method comprises: determining, using at least one processor of a vehicle, that the vehicle has lost external signals (or is receiving degraded external signals) that are used for estimating a position of the vehicle; determining, using the at least one processor, a set of mobile beacons that are available to assist in estimating the position of the vehicle; receiving, using a communication device of the vehicle, broadcast signals from the set of mobile beacons, the broadcast signals including localization data for the set of mobile beacons; selecting, using the at least one processor, a subset of localization data from the set of mobile beacons for assisting in the position estimation of the vehicle; and estimating, using the at least one processor, the position of the vehicle using the subset of localization data.

Abstract: Techniques are disclosed relating a computer system in a power-down state receiving a communication from a remote computer system and performing a task indicated by the communication. The computer system in a power-down state performs the task without transitioning from the power-down state into a power-up state. Exemplary tasks performed in the power-down state include uploading one or more files to a remote computer system, downloading one or more files from a remote computer system, deleting one or more files from the computer system, accessing input/output devices, disabling the computer system, and performing a memory check on the computer system.

Abstract: Embodiments provide for methods and portable positioning devices adapted to determine a geospatial position of a point of interest. In one embodiment, the portable positioning device comprises an antenna, a levelling detector, an imaging device, a display unit and a processing unit. The antenna may be adapted to receive satellite information signals. The levelling detector is arranged relative to the antenna for detecting whether the antenna is positioned horizontally. The imaging device has an optical axis and a sighting axis. In one embodiment, the sighting axis intersects an antenna axis. In another embodiment, the sighting axis is aligned with the antenna axis. The display unit may be provided for assisting in identifying the point of interest within a field of view of the imaging device and for assisting in identifying whether the antenna is horizontally levelled and whether a phase center and the point of interest are vertically aligned.

Abstract: Methods and systems for calibrating the return and forward links of a satellite communication system are provided according to embodiments of the invention. The phase and/or amplitude variations caused by the return and forward links are calculated and/or estimated to aid in beamforming, such as ground-based beamforming. Calibration earth stations, distributed within one or more beam patterns, may be used to transmit calibration codes to the gateway to calibrate the return link. Return links variations may be estimated using a weighted minimum mean square algorithm at the gateway. Forward links may be calibrated with calibration codes transmitted from the gateway through a hybrid matrix to at least one calibration station. Forward calibration links may also calibrate for temperature-dependent signal variations such as diplexer variations at the satellite.

Abstract: A universal multi-channel receiver for receiving and processing signals from different navigation systems is provided. The universal receiver is implemented as an ASIC receiver with a number of universal channels. The receiver with universal channels is capable of receiving and processing signals from navigation satellites located within a direct access zone. The universal receiver has a plurality of channels that share the same memory. The universal receiver can determine its coordinates using any of the existing navigation systems (GPS, GLONASS, Beidou and GALILEO). The receiver can receive and process any (PN) signals.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a wireless communication device, such as a repeater, may select a polarization configuration for multiple antennas that form beams for forwarding wireless communications between a first wireless device and a second wireless device. The repeater may forward wireless communications between the first wireless device and the second wireless device according to the polarization configuration. Numerous other aspects are described.

Abstract: A position estimation apparatus estimates the position of a radio communication device that outputs a signal, where the apparatus includes a distance estimating section, a first position estimating section, a second position estimating section, and a final position estimating section, where the distance estimating section estimates actual distances between wireless access points receiving the signal and the radio communication device as estimated distances based on the reception strength of the signal, where the first position estimating section estimates the position of the radio communication device, where the second position estimating section estimates a circle centered at one of the wireless access points with the maximum reception strength, and where the position estimated by the final position estimating section is estimated as the position of the radio communication device.

Abstract: An apparatus for determining a precise location including: a plurality of unmanned aerial vehicles each having a first broadband signal module and a global position system GPS receiver attached thereonto and flying in the air; and a terminal provided at a location and determining the location by communication with the first broadband signal modules. In addition, a method for determining a precise location including: respective GPS receivers receiving GPS signals from artificial satellites and detecting locations of each of the plurality of unmanned aerial vehicles, transmiting locations of the unmanned aerial vehicles and distances between the unmanned aerial vehicles and the terminal and determining a location of the terminal using information received from the first broadband signal modules.

Abstract: A base station for providing dynamic power management is disclosed, comprising, a processor within an enclosure mounted in a vehicle, a power management unit coupled to the processor, a controller area network (CAN) bus monitoring system coupled to the power management unit and to a CAN bus of the vehicle, a voltage measurement module also coupled to the power management unit and to a battery of the vehicle; a baseband processor coupled to the processor, a first wireless access functionality coupled to the baseband processor, and a second wireless access functionality coupled to the baseband processor, wherein the power management unit is coupled to each of the first and the second wireless access functionality to enable access radio bringup, access radio shutdown, and graceful user detach based on a power state at the power management unit.

Abstract: An entity, such as a mobile device or base station, measures downlink position referencing signals (PRS) occasions or uplink position sounding referencing signal occasions for supporting estimating the position of the mobile device. The entity, for example, performs a plurality of positioning measurements from a plurality of consecutive PRS occasions received in a bundle from one or more base stations or from a mobile device. Each PRS occasion may include one or more slots and may be narrowband or non-narrowband. The bundled, e.g., consecutive, PRS occasions may be transmitted with a periodicity that is sufficient to maintain a desired throughput. Moreover, with the use of bundled PRS occasions, power consumption of the mobile device, as well as effects of clock drift and mobile device movement, may be minimized.

Abstract: Devices, methods, and systems for airside performance analysis are described herein. One system includes a computing device to: receive key performance indicator (KPI) data from a number of different system monitors, correlate the KPI data to generate a number of graphical representations of the correlated KPI data, link the number of widgets to update the corresponding report based on a received selection, and display a number of widgets that generate a corresponding report of the correlated KPI data.

Abstract: A method and system for operating a user equipment (UE) wherein a first set of radio access procedures are supported when the UE is in a first operating state, and a second set of radio access procedures are supported when the UE is in a second operating state.

Abstract: Disclosed is a method for controlling an electronic device. The method for controlling an electronic device may comprise the steps of: determining whether there is an obstacle in the first direction from the electronic device; if it is determined that there is an object in the first direction, determining that the electronic device is disposed indoors; and if it is determined that there is no obstacle in the first direction, determining that the electronic device is disposed outdoors.

Abstract: A wireless receiver (10) includes a down converter module (210) operable to deliver a signal having a signal bandwidth that changes over time, a dynamically controllable filter module (200) having a filter bandwidth and fed by said down converter module (210), and a measurement module (295) operable to at least approximately measure the signal bandwidth, said dynamically controllable filter module (200) responsive to said measurement module (295) to dynamically adjust the filter bandwidth to more nearly match the signal bandwidth as it changes over time, whereby output from said filter module (200) is noise-reduced. Other wireless receivers, electronic circuits, and processes for their operation are disclosed.

Abstract: A device and method in a vehicle control unit for providing electronic commerce transaction authentication are provided. Upon receiving an electronic commerce transaction request relating to a transaction source, the vehicle control unit authenticates the transaction source against a vehicle travel route parameter by comparing the source location data with the vehicle travel route parameter. When the source location data compares favorably with the vehicle travel route parameter, an electronic commerce authentication is generated in response to the request, and transmitted.

Abstract: A solution for providing differentiated positioning services in a wireless communication system is provided. For example, a method to be performed by a wireless device is provided, which includes requesting a high accuracy positioning information from the network, e.g. from a network node. The method further includes obtaining information from the network in response to the request, which is valid for a predefined period of time, and which enables the wireless device to obtain the high accuracy positioning information during the predefined period of time. The method further includes performing positioning or assisting performance of positioning based on the obtained high accuracy positioning information.

Abstract: Search and rescue (SAR) systems utilizing Earth-orbiting satellites are provided. In one implementation, a SAR system comprises a plurality of reference beacons, each having a known geographical location, and a ground-based station. The ground-based station includes one or more antennas for communicating with the reference beacons via a plurality of Earth orbiting satellites. The ground-based station is configured to receive reference signals from each of the reference beacons and calculate estimates of the locations of the reference beacons from the received reference signals. Also, the ground-based station is configured to calculate system calibration factors based on the location estimates and known geographical locations of the reference beacons. The ground-based station is further configured to receive distress signals from at least one distress beacon via the Earth-orbiting satellites and calibrate the distress signals based on the system calibration factors.

Abstract: A method for determining a location of a target includes: obtaining a plurality of guess distance values of a plurality of satellites, respectively; utilizing satellite signals received from the plurality of satellites to estimate a plurality of pseudo range values of the plurality of satellites, respectively; comparing the guess range values with the pseudo range values to generate a residual vector; and utilizing a processing unit for applying a rank-based approach based on the residual vector to generate a calculation result. The location of the target is derived from the calculation result.

Abstract: Techniques are disclosed relating a computer system in a power-down state receiving a communication from a remote computer system and performing a task indicated by the communication. The computer system in a power-down state performs the task without transitioning from the power-down state into a power-up state. Exemplary tasks performed in the power-down state include uploading one or more files to a remote computer system, downloading one or more files from a remote computer system, deleting one or more files from the computer system, accessing input/output devices, disabling the computer system, and performing a memory check on the computer system.

Abstract: Navigation beacons may be trained to receive signals of opportunity from one or more vehicles, to recognize their own position based on such signals, and to transmit information regarding their own position to one or more other vehicles accordingly. The navigation beacons may be of small size and feature a basic construction including one or more transceivers, power sources and the like, and may communicate via a Bluetooth® Low Energy, Ultra Wideband or long-range low-power wireless standard, or any other standard. The navigation beacons may be installed in any location, preferably being mounted to one or more existing fixed structures or facilities (e.g., transportation structures or facilities), and may operate in active and/or passive modes when learning their positions or servicing position information to one or more remote devices.

Abstract: A method for determining protection levels that comprises a preliminary phase carried out at least one time and a main phase carried out upon determining each new navigation solution. The preliminary phase comprises the steps of acquiring a first error value, providing a set of numbers of monitored faults, determining a plurality of computation coefficients, and storing the set of determined computation coefficients. The main phase includes the steps of determining a current number of monitored faults, and determining a protection level of the corresponding navigation solution by using an integrity relationship and the computation coefficients determined during the preliminary phase.

Abstract: A method for Real Time Kinematic satellite positioning includes receiving navigation satellite carrier signals, receiving phase correction signals from a reference station, calculating a set of integer phase ambiguities from double-differenced measurements of pseudo-range and phase, and calculating a relative position of the mobile receiver from the set of integer phase ambiguities and the double-differenced measurements of pseudo-range and phase.

Abstract: A distress flare including a cartridge including two ends connected by a side surface; activation device intended to expel the cartridge into the sky; an inflatable shell, covering the side surface, suitable for being deployed under the effect of deploying device and of diffusing the visible light; illuminating device powered by a battery and capable of emitting visible light, the illuminating device being arranged on the side surface.

Abstract: A system for indoor localization using satellite navigation signals in a Distributed Antenna System includes a plurality of Off-Air Access Units (OAAUs). Each of the plurality of OAAUs is operable to receive an individual satellite navigation signal from at least one of a plurality of satellites and operable to route signals optically to one or more DAUs. The system also includes a plurality of remote DRUs located at a remote location. The plurality of remote DRUs are operable to receive signals from a plurality of local DAUs. The system further includes an algorithm to delay each individual satellite navigation signal for providing indoor localization at each of the plurality of DRUs and a GPS receiver at the remote location used in a feedback loop with the DRU to control the delays.

Abstract: User authentication techniques based on geographical locations associated with a client device are provided. An example method for authentication of the client device includes receiving an authentication request from the client device. The method may include establishing current geographical location of the client device. The method may further include establishing a trusted tolerance geographical area associated with the client device. After establishing the trusted tolerance geographical area, the method may proceed with determining whether the current geographical location of the client device is within the trusted tolerance geographical area. The method may further include authenticating the client device based on the determination that the current geographical location of the client device is within the trusted tolerance geographical area.

Abstract: A solution for providing differentiated positioning services in a wireless communication system is provided. For example, a method to be performed by a wireless device is provided, which includes requesting a high accuracy positioning information from the network, e.g., from a network node. The method further includes obtaining information from the network in response to the request, which is valid for a predefined period of time, and which enables the wireless device to obtain the high accuracy positioning information during the predefined period of time. The method further includes performing positioning or assisting performance of positioning based on the obtained high accuracy positioning information.

Abstract: A system and method of determining adaptive wireless coverage configurations is disclosed. One or more network devices receive wireless signals from a wireless device at respective signal strength values that are above a minimum threshold. The network devices are identified as a first subset of network devices. Additionally or alternatively, one or more network devices transmit wireless signals that are received by the wireless device at respective signal strength values that are above a minimum threshold. The network devices are identified as a second subset of network devices. Based on the number of network devices in the first subset of network devices and/or the number of network devices in the second subset of network devices, a wireless coverage configuration corresponding to a location associated with the wireless device is modified.

Abstract: A method of implementing convergence of a Global Navigation Satellite System (GNSS) receiver is disclosed. A GNSS receiver which is coupled with a mobile machine is shut down. The GNSS receiver is in a converged state at shut down. The GNSS receiver is automatically powered up at a preset time. A convergence algorithm is automatically initiated prior to start of work that utilizes the GNSS receiver.

Abstract: A method of implementing fast GNSS convergence by relative positioning is disclosed. A GNSS receiver which is coupled with a mobile machine is shut down. The GNSS receiver is in a converged state at shut down. A movement sensor is monitored to determine if net movement of a GNSS antenna coupled with the mobile machine exceeds a threshold net movement parameter while the GNSS receiver is shut down. Upon power up of the GNSS receiver, a shorter convergence algorithm is initiated in response to determining that the threshold net movement parameter has not been exceeded. The shorter convergence algorithm is also initiated upon power up of the GNSS receiver in response to determining that the threshold net movement parameter has been exceeded but information from the movement sensor has been used to update the location of the GNSS receiver since said shut down.

Abstract: A method of implementing convergence selection of a Global Navigation Satellite System (GNSS) receiver is disclosed. In accordance with one embodiment, a GNSS receiver which is coupled with a mobile machine is shut down. The GNSS receiver is in a converged state at shut down. A movement sensor is monitored to determine if net movement of a GNSS antenna coupled with the mobile machine exceeds a threshold net movement parameter while the GNSS receiver is shut down. Upon power up of the GNSS receiver, a shorter convergence algorithm is initiated in response to determining that the threshold net movement parameter has not been exceeded and a longer convergence algorithm is initiated in response to determining that the threshold net movement parameter has been exceeded.

Abstract: Methods, systems and devices for determining a more precise location of a fixed wireless device and providing an enhanced location based service (eLBS). A fixed wireless device may be configured to determine its approximate location (e.g., a current location waypoint, etc.), communicate with other fixed or mobile wireless devices to receive location information, and determine a more precise location of the fixed wireless device based on the approximate location and the received location information. The fixed wireless device may use the computed location information to provide a location based service and/or send the more precise location to another wireless device for use in providing a location based service.

Abstract: A base station includes a storage device to store results of carrier sensing performed respectively on a data transmission side and on a data reception side with respect to a plurality of sub-bands in unlicensed frequencies being the frequencies of which a use is not licensed for data transmission, and a controller to extract sub-bands of the unlicensed frequencies being determined that are in an idle status or have high possibility to be in the idle status by both of the data transmission side and the data reception side in the carrier sensing results as candidates for sub-bands of the unlicensed frequencies to be used for transmitting data by the data transmission side.

Abstract: A receiver (100) is provided for signals of different signal strengths and modulated with respective pseudorandom noise (PN) codes. The receiver (100) includes a correlator circuit (120) operable to correlate the signals with a selectable locally-issued PN code having a Doppler and a code lag to produce a peak, the correlator circuit (120) being subject to cross correlation with a distinct PN code carried by least one of the signals that can produce cross correlation; and a cross correlation circuit (370, 400) operable to generate a variable comparison value related to the cross correlation as a function of values representing a Doppler difference and a code lag difference between the locally-issued PN code and the distinct PN code, and to use the variable comparison value to reject the peak as invalid from cross correlation or to pass the peak as a valid received peak.

Abstract: User authentication techniques based on geographical locations associated with a client device are provided. An example method for authentication of the client device includes receiving an authentication request from the client device. The method may include establishing current geographical location of the client device based on metadata received from the client device. The method may further include establishing a trusted tolerance geographical area based on historical location area associated with the client device. After establishing the trusted tolerance geographical area, the method may proceed with determining whether the current geographical location of the client device is within the trusted tolerance geographical area. The method may further include authenticating the client device based on the determination that the current geographical location of the client device is within the trusted tolerance geographical area.

Abstract: A system and method of determining adaptive wireless coverage configurations is disclosed. One or more network devices receive wireless signals from a wireless device at respective signal strength values that are above a minimum threshold. The network devices are identified as a first subset of network devices. Additionally or alternatively, one or more network devices transmit wireless signals that are received by the wireless device at respective signal strength values that are above a minimum threshold. The network devices are identified as a second subset of network devices. Based on the number of network devices in the first subset of network devices and/or the number of network devices in the second subset of network devices, a wireless coverage configuration corresponding to a location associated with the wireless device is modified.

Abstract: A head-mounted display (HMD) is wirelessly coupled to a console or a relay depending on the relative positions of the HMD, the console, and the relay. The HMD communicates wirelessly with the console using a narrow beam that is oriented in a particular direction. As the position of the HMD changes, the quality of the communication link between the HMD and the console may degrades. In response to the degradation, the HMD forms a communication link with a relay, which operates as an intermediary between the HMD and the console. The relay communicates with the HMD over a dedicated communication channel that is isolated from the communication channel over which the relay communicates with the console. A calibration module in the relay iteratively adjusts a noise reduction parameter until the effects of the undesirable feedback are eliminated.

Abstract: An inter-user equipment discovery method, apparatus and system are disclosed. In an embodiment, the method includes sending, by first user equipment, a discovery request message to a first proximity-based service entity, wherein the discovery request message comprises initial location information of the first user equipment and receiving a discovery response message sent by the first proximity-based service entity, wherein the discovery response message comprises a first code word of the first user equipment. The method further include generating a discovery message according to location offset information and the first code word, wherein the location offset information is an offset between a current location and an initial location of the first user equipment and broadcasting the discovery message, wherein the discovery message is used by a second user equipment to determine a location of the first user equipment.

Abstract: Systems and methods are provided for optimizing a relay node in a wireless communication network. A plurality of base stations may be provided as well as at least one antenna at a relay node, the antenna operably coupled to a rotation mechanism. The plurality of base stations can be scanned by the antenna, the scanning using one or more control parameters dictating a portion of a scanning process. Based on the scanning, an optimal base station may be determined and/or an optimal antenna position may be determined. The antenna can adjust to the optimal position and/or can attach to the optimal base station to provide an optimal backhaul link.

Abstract: A system for estimating carrier phases of radio signals in a satellite navigation system receiver for coordinate determination includes a complex of reference signals (CRS), wherein, in each jth satellite channel, a digital reference signal RefSigj, represents an output phase and frequency-controlled oscillation of a corresponding numerically-controlled oscillator (NCOj) for each jth satellite channel, the phase of the oscillation of the NCOj tracking a carrier signal received from the jth satellite; and an adaptation complex (AC) that, in response to vibration or movement of the receiver, changes (expands or reduces) an effective bandpass of the CRS, producing control signals that determine phase and frequency changes in the corresponding NCOj for reducing dynamic distortions in coordinate measurements.

Abstract: A method of determining a position of a GNSS receiver includes: receiving, at the GNSS receiver, information from at least two GNSS satellites and an estimated location area from a non-GNSS positioning application, determining candidate pseudoranges corresponding to candidate correlation peaks determined based on the information received from the at least two GNSS satellites; determining possible positions of the GNSS receiver using the candidate pseudoranges and the estimated location area; determining a best possible position of the GNSS receiver from the possible positions; and setting the best possible position as the position of the GNSS receiver; wherein when multiple candidate correlation peaks corresponding to one of the at least two GNSS satellites are determined, the estimated location area is usable to reduce the number of candidate correlation peaks prior to candidate pseudoranges being determined.

Abstract: A head-mounted display (HMD) is wirelessly coupled to a console or a relay depending on the relative positions of the HMD, the console, and the relay. The HMD communicates wirelessly with the console using a beam that is oriented in a particular direction. As the position of the HMD changes, the quality of the communication link between the HMD and the console may degrades. In response to the degradation, the HMD forms a communication link with a relay, which operates as an intermediary between the HMD and the console. The relay communicates with the HMD over a dedicated communication channel that is isolated from the communication channel over which the relay communicates with the console. An RF signal path with calibration features in the relay iteratively adjusts a feedback reduction parameter until the effects of the undesirable feedback are eliminated.

Abstract: A system and method for providing location information using a long baseline accelerometer/GNSS system. A first set of accelerometers is operatively associated with the first GNSS antenna while a second set of accelerometers is operatively associated with a second (or more) GNSS antenna. The multiple assemblies are separated by predefined distances and held rigid to each other. Accelerometer data is combined with the GNSS data to provide improved navigation and location information.

Abstract: An error correcting location system includes a ground station with fixed reference coordinates. The ground station may receive satellite broadcast messages from a plurality of location system satellites. Further, the ground station may determine location coordinates based on the satellite broadcast messages, and compare the location coordinates to the fixed reference coordinates to determine a compensation value. In addition, the ground station may send the compensation value to location system devices. Upon receipt of the compensation value, the location system devices may utilize the compensation value to generate highly accurate location coordinates.

Abstract: Systems and methods for estimating a position of a receiver within a venue using localized networks of beacons. Certain aspects relate to different configurations of networks. Other aspects relate to estimating the position of the receiver when the receiver approaches an edge of a localized network of beacons.

Abstract: Fixed infrastructure devices (FIDs) may be configured to work with other devices (e.g., other FIDs, mobile wireless devices, etc.) to obtain or improve location information and/or provide enhanced location based services (e.g., emergency location service, commercial location service, internal location service, lawful intercept location service, etc.) to other devices or programs. For example, a first fixed wireless device may be configured to receive information that was obtained via a geospatial system, and determine whether it is able to establish a location fix based on this information. In response to determining that it is unable to establish a location fix based on the received information, the device may establish a communication group and/or collect additional location information from devices that belong to the communication group. The device may use this information to compute a new three-dimensional location fix, and use this new fix to provide the location based service.

Abstract: User authentication techniques based on geographical locations associated with a client device is provided. A network connection can be established between two or more host machines and a client device. Upon a request received from the client device by one of these host machines, round trip times of test messages may be measured between the client device and each of the host machines. The round trip times can be utilized to determine the current geographical location of the client device. If the location is within a tolerance geographical area, the client device may be authenticated. Otherwise, the authentication may fail or additional security procedures may be implemented. In some examples, a travel time from a historical geographical location to current geographical location can be determined. This data may be also utilized in the user authentication process.

Abstract: An authentication method for a communication network includes a registration step, an inquiry step, an answering step and a verification step. The authentication method further includes an emergency authentication mode if a response code is not received by a requesting end within a predetermined period of time or if a first confirmation code is verified to be incorrect by a requesting end. In another embodiment, an authentication method for a communication network includes a registration step, a first inquiry step, a second inquiry step, a first answering step, a second answering step and a verification step. The authentication method in the other embodiment also includes an emergency authentication mode if a second response code is not received by the requesting end within a predetermined period of time or if a third tested code is verified to be incorrect.