1393 results about "Satellite navigation system" patented technology

Electronic devices may be provided that contain wireless communications circuitry. The wireless communications circuitry may include radio-frequency transceiver circuitry and antenna structures. The antenna structures may include conductive housing structures such as a peripheral conductive housing member. The antenna structures may be based on an inverted-F antenna resonating element or other types of antenna resonating element. An electronic device may have near field communications circuitry and non-near-field communications circuitry such as cellular telephone, satellite navigation system, or wireless local area network transceiver circuitry. Antenna structures may be configured to handle signals associated with the non-near-field communications circuitry. The antenna structures may also have portions that form a near field communications loop antenna for handling signals associated with the near field communications circuitry.

The invention relates to a navigation system receiver comprising at least two antennas, one of which is a "reference" antenna. A multiplexer multiplexes the signals from the antennas, and a first processor situated downstream from the multiplexer delivers at least one navigation parameter on the basis of the signals from the multiplexer. The receiver includes a second processor having an input receiving in continuous manner signals from the reference antenna to deliver at least one reference signal representative of a position parameter of the reference antenna. Processor means process the signals from the multiplexer while taking account of at least one said reference signal.

The invention discloses an image-processing-based unmanned plane accurate position landing method, which comprises the following steps: (1) a GPS (global position system) satellite navigation system enables an unmanned plane to be located above a ground parking apron; (2) an air pressure height measurement gauge and a distance measurement module of an ultrasound radar are combined to control the ground clearance for the unmanned plane to land; (3) a vision module identifies a coarse positioning identification domain in real time, and combines Hough Transform and RGB mean value method and gate position identification to process a coordinate of a targeted landing point; (4) when landing of the unmanned plane meets the threshold condition of the coarse positioning identification domain, the algorithm in the step (3) is utilized to perform accurate positioning treatment on the accurate positioning identification domain; and (5) the unmanned plane is controlled for accurate landing by taking the treated deviation value as the input quantity and adopting the double PID algorithm. According to the invention, the defect that insufficient GPS accuracy of the unmanned plane causes a fault landing is overcome, the intelligence for the unmanned plane control is improved, and the cost for using an accurate sensor is greatly reduced.

An agricultural seeder or fertilizer having a meter device which dispenses seed or fertilizer to a plurality of ground-engaging members. The supply of metered seed or fertilizer to each of the ground-engaging members is controlled via input from a GPS / GNSS satellite navigation system to prevent the meter device delivering seed or fertilizer to selected of the ground-engaging members which would otherwise pass over soil which has been previously seeded or fertilized. Raising means, responsive to input from said GPS / GNSS satellite navigation system detecting that the device is travelling or is about to travel over areas of soil that has been previously seeded or fertilized, is further is provided to raise the selected ground-engaging members to which delivery of seed / fertilizer has been prevented in order to prevent soil which has been previously seeded or fertilized from being disturbed. A method of operating a seeder / fertilizer implement to achieve the aforesaid is further disclosed.

Low-energy consumption techniques for locating a movable object using a global satellite navigation system (GNSS) are provided. A mobile station attached to or included in a movable object can communicate bidirectionally with a fixed base station to determine a location of the movable object. The mobile station may communicate an estimated position to the base station and receive from the base station a set of GNSS satellites that are visible to the mobile station. The mobile station can acquire satellite timing information from GNSS signals from the set of satellites and communicate minimally-processed satellite timing information to the base station. The base station can determine the position of the mobile station and communicate the position back to the mobile station. By offloading much of the processing to the base station, energy consumption of the mobile station is reduced.

The invention relates to the technical field of wireless communication networks, in particular to an indoor and outdoor integrated high-precision positioning and navigation system as well as a positioning method thereof. The system comprises a map data construction unit, an indoor ultra-wideband positioning and navigation unit, an outdoor BD / GPS positioning and navigation unit, an indoor and outdoor positioning data fusion unit, a central server unit and a terminal display unit, wherein the indoor ultra-wideband positioning and navigation unit is used for performing indoor space positioning in a ranging mode, the outdoor BD / GPS positioning and navigation unit is used for performing outdoor space positioning through a Beidou satellite navigation / GPS satellite navigation system, the indoor and outdoor positioning data fusion unit is used for judging whether a positioning label is indoor or outdoor and can intelligently switch positioning modes according to the judgment result and fuse indoor and outdoor positioning manners. Problems that positioning and navigation of personnel and objects in a large-range area are difficult to realize, not high in precision and the like at present are solved, and large signal interference and positioning deviation caused by mutual interference among signals can be avoided in the ranging mode.

A portable electronic device such as a mobile telephone is used with a global satellite navigation system (e.g., GPS) to set up a number of respective profiles that have one or more respective operational settings for the mobile phone, each coordinated with a respective area, such as a home area, an office area, an undefined area, etc. The mobile phone is used with the global satellite system to define a virtual room or area; and during subsequent use of the mobile phone, when it is in a given virtual room or area or is in an undefined area, the mobile phone automatically adjusts to the profile and setting(s) that are coordinated with such area. A virtual room can be defined by positioning the mobile phone at three or more different locations and using a GPS determining virtual boundaries based on signals representing such locations.

In order to determine positional information, about a mobile robot, Real Time Kinematic (RTK) Global Satellite Navigation System (GNSS) measurement data are obtained by at least two GNSS receivers mounted on the mobile robot. Estimates of the covariance matrices of the measurement data are computed. The RTK GNSS measurement data are combined according to the covariance matrices to obtain enhanced positional information. The results may be fused with data from an IMU to obtain driftless attitude and / or localization information.

The present invention consists of a method to ensure the integrity of the navigation solution even when the user is in a non controlled environment as it is the case of urban and road applications. The method requires the existence of a Signal In Space with guaranteed integrity as the one today provided by SBAS systems or from GBAS, Galileo or GPS-III in the future. The invention covers the algorithms to detect and isolate errors present in non controlled environments such as multipath and compute resulting position error bounds with the required level of integrity. This invention substantially increases the field of application of satellite navigation systems with associated integrity to the so-called liability critical applications.

The invention provides a double-antenna GNSS (Global Navigation Satellite System) / INS (Inertial Navigation System) deeply integrated navigation method and device. The device comprises a power supply module, an MEMS (Micro Electro Mechanical System) inertial measurement unit, a radio frequency module, an FPGA (Field Programmable Gate Array) module, a DSP (Digital Signal Processor) module and at least two antennas. According to the device, with the assistance of an INS, the probability of cycle slip of the GNSS can be reduced effectively, the integer ambiguity searching space of the GNSS is reduced, attitude measurement information is guaranteed to be continuously outputted, and the tracking loop robustness of the GNSS is enhanced; and with the assistance of a double-antenna GNSS, quick initial alignment of the INS can be realized, the attitude observability of the INS is improved, and the attitude divergence of the INS is inhibited.

The invention relates to a system for evaluating the performance of a satellite navigation system. The system has a real-time evaluation mode and a playback evaluation mode and comprises a system positioning accuracy evaluation module, a system velocity measurement accuracy evaluation module, a system availability evaluation module, a system completeness evaluation module, a configuration holding capacity evaluation module and a multipath delay evaluation module, wherein the system positioning accuracy evaluation module evaluates system positioning accuracy by calculating a user equivalent range error and using a statistical method; the system velocity measurement accuracy evaluation module obtains a system velocity measurement accuracy conclusion by calculating a user pseudo-range error and using the statistical method; the system availability evaluation module respectively calculates the availability of the common mode and a wide area differential mode to obtain a system availability conclusion; the system completeness evaluation module obtains a system completeness conclusion by calculating the completeness of three parts, namely a satellite, a ground operational control system and a receiver; the configuration holding capacity evaluation module obtains a configuration holding capacity conclusion by counting constellation occupied time percentage; and the multipath delay evaluation module obtains a multipath delay conclusion by calculating the delay, amplitude and phase difference of a multipath signal relative to a direct signal. The system is easy to implement in engineering and can effectively evaluate the performance of the satellite navigation system.

An autonomous navigation system for an orbital platform incorporating a global positioning system based navigation device optimized for low-Earth orbit and medium-Earth orbit applications including a 12 channel, GPS tracking application-specific integrated circuit (15) operating in concert with a computer system (90) implementing an extended Kalman filter and orbit propagator which autonomously generates estimates of position, velocity and time to enable planning, prediction and execution of event-based commanding of mission operations.

The invention provides an integrated navigation method and equipment based on multisource information fusion. The method comprises the following steps: obtaining multisource navigation information, namely obtaining navigation related information from one or more of a global satellite navigation system GNSS, an inertial navigation system INS, a multimode region difference augmentation system MLDAS, a pressure altimeter and timekeeping equipment, which are arranged on an aircraft; performing fusion treatment on multisource information by using a federal wave filter, wherein the federal wave filter comprises a main wave filter and a plurality of local wave filters connected with the main wave filter, and each kind of the multisource navigation information and a reference signal are jointly input to one local wave filter; triggering the local wave filters to respectively calculate local estimation values and error covariance matrixes; triggering the main wave filter to perform wave filtering on the reference signal, and performing optimal infusion on the wave filtering results of the reference signal according to output results of the local wave filters and the local wave filters, so as to obtain a global optimum estimation value. Therefore, the availability and the integrity of on-board navigation equipment are improved.

The invention provides a framing method of the receiver front-end of multimode satellite navigation, which discloses a frontend chip of the receiving RF of multimode satellite navigation which is applicable to a plurality of satellite navigation systems. The method of the invention comprises six modules which are a multimode PF frontend low-noise amplifier / mixer group of monolithic integrated and completed type, a reconfigurable image rejection filter, a band-variable gain amplifier, an analog-to-digital converser, a configurable frequency synthesizer and a multimode control logic module. The reconfigurable module can realize the distribution of functional parameters according to the requirement through the multimode control logic management, causing the working performance to be optimized and meeting the functional requirement on the RF front end of the receiving platform of multimode satellite navigation. The framing method of the invention requires no external supporting accessories and has the advantages of being easy to carrying out cascade connection with preceding and backward stages, high gain, small noise coefficient and good integration. The invention is applied to the current communication and navigation positioning equipment for receiving multimode satellite navigation signals, has a wide application range and quite remarkable economic benefit, is largely on demand, supports the integration making use of multimode satellite navigation positioning information, improves positioning precision and has large social benefit.

A luminous display for automotive satellite navigation systems includes a panel equipped with light sources, for example made up of LEDs, arranged in a pre-ordered configuration of discrete segments, which can be combined with one another according to paths corresponding to the representation of a plurality of encoded generally arrow-shaped pictograms, each of which indicates a respective direction to follow indicated by the navigation system. The path to follow is highlighted with respect to possible alternative paths represented by the pictograms.

A location of a mobile device is determined using Wi-Fi signals. The location of a moving mobile device may be initially determined using a satellite navigation system. When the speed at which the mobile deice is moving falls below a threshold, a determination is made as to whether Wi-Fi signals are receivable at the mobile device. If Wi-Fi is receivable, Wi-Fi signals are used to determine the location of the mobile device rather than the satellite navigation system. The Wi-Fi signals are continuously or repeatedly used to identify the location of the mobile device until the speed at which the mobile device is moving surpasses the threshold or until Wi-Fi signals are no longer receivable at the mobile device. Since Wi-Fi sensors of mobile devices consume less power than satellite navigation sensors, the power consumption of the mobile device is reduced when mobile device location is determined using Wi-Fi signals.

The invention discloses a new method for RAIM (receiver autonomous integrity monitoring) based on a satellite selecting algorithm in a multimode satellite navigation system. The method comprises the steps of first determining space position information of satellites according to a navigation message and eliminating satellites with a small elevation angle according to a shielding angle; determining an observation matrix including only one clock correction item according to clock correction conversion factors in the navigation message; selecting p satellites from N visible satellites so as to be used for positioning calculation of a receiver, acquiring a satellite combination, which enables the GDOP (geometric dilution of precision) to be minimum, through the satellite selecting algorithm to act as calculating satellites, and determining a weight matrix in WLS (weighted least squares) according to parameters such as the carrier-to-noise ratio, the loop bandwidth, pre-check integral time and the like of satellite signals; carrying out RAIM availability detection according to a false alarm rate and a missed alarm rate which are preset by the receiver, and calculating a pseudo-range residual error threshold value after positioning according to the false alarm rate and a degree of freedom in Chi-squared distribution; carrying out global detection at first, then carrying out local monitoring in a circumstance that a fault satellite exists, determining calculation satellites again through satellite selection, and finally carrying out positioning calculation through selecting satellite combinations within the threshold value. The method disclosed by the invention is simple, high in fault recognition rate, not only applicable to multi-mode and multi-fault satellite navigation systems, but also applicable to single-mode and multi-fault satellite navigation systems, thereby providing new ideas for carrying out RAIM by a modern GNSS (global navigation satellite system).

The invention provides a real-image navigation apparatus capable of being mounted on a vehicle having transparent equipment (windows) installed therein, including an image-capturing unit adapted to instantly capture images of a road in front of a vehicle; a satellite navigation system adapted to navigate and generate navigation routes and driver-assisting navigation information; a comparing unit adapted to compare and determine the consistency between obtained images captured by the image-capturing unit and road parameters of mapping information pre-stored in the system, and further output three-dimensional navigation routes planned by cooperating with the system; and a see-through display unit mounted on transparent equipment installed within the vehicle to display real-time driver-assisting navigation information and 3-D navigation routes outputted by the comparing unit to the user / driver, thereby presenting useful navigation data and related geographical information without overly diverting eye focus or obstructing the driver's view, and thus increase driving safety.

The invention discloses a compatible navigation receiver positioning system and a positioning method thereof. The system comprises a parameter configuring module, a data preprocessor, a satellite parameter calculating module, a pseudo-distance modifying module, a coordinate conversion module, a positioning calculating module, a kalman filter and a message forming module. The positioning method comprises the steps of: reading a configuration parameter of a receiver; extracting ephemeris data, almanac data and observation data; obtaining parameter information of effective satellites; obtaining the position of the receiver and the speed of the receiver; and generating a message by the navigation information. The invention realizes alternative use of the global positioning system, the independent navigation of the second big dipper navigation system breaks away from the dependency to the other navigation systems at emergency period, and the combination of the many satellite navigation systems increases the quantity of the effective satellites, so as to guarantee the continuity, the usability and the security of satellite positioning service, enhance the geometric figure intensity of the observation satellites, and improve the reliability of the whole global positioning system.

The embodiment of the invention provides a method and a device for calibrating a local clock based on satellite time service. The method mainly comprises the following steps of: performing frequency multiplication on a local clock signal by using a digital phase-locked loop to acquire a frequency multiplication clock; performing frequency counting on a satellite clock signal received by a satellite receiver by using the frequency multiplication clock to acquire a count value corresponding to the satellite clock signal, and subtracting the count value from a count value corresponding to a local standard clock to acquire a count difference value; and acquiring clock offset between the local clock signal and the satellite clock signal according to the count difference value, and calibrating the local clock according to the clock offset. By the method and the device provided by the embodiment of the invention, the satellite clock signal is subjected to frequency counting through the frequency multiplication clock, so that the offset between the local clock signal and a clock signal output by a global positioning system (GPS) / Beidou satellite navigation system can be quickly acquired, and input parameters can be provided for a local clock control algorithm.

The invention discloses a method and corresponding device for taming crystal oscillation frequency of a time-keeping device, which comprises the following steps of: step 1, acquiring the standard time pulse A that is located and output by a navigation satellite; step 2, acquiring the standard time pulse B output by device crystal oscillation fractional frequency; step 3, measuring the clock difference between the standard time pulse A and the standard time pulse B; and step 4, if clock difference exists between A and B, adjusting the crystal oscillation frequency of the device to make the clock difference be in the allowed scope. For the time-keeping equipment with pressure control and temperature compensating crystal oscillation or pressure control crystal oscillation, the frequency deviation of the corrected crystal oscillation can be detected in real time by the method provided by the invention to eliminate the time-keeping error caused by crystal oscillation frequency deviation and avoid accumulation of error. Therefore, the invention is suitable for various satellite navigation systems, such as GPS, Beidou first generation navigation satellite, Beidou second generation navigation satellite, GLONASS, GALILEO and other satellite navigation systems.

The invention discloses a Beidou three-frequency non-differential non-combined observation value time transmission system and method. The method includes the steps that phase observation value, pseudo-range observation value, satellite ephemeris, earth rotation, antenna phase center and other parameters of China Beidou satellite navigation systems at two time transmission stations are obtained; data check, gross error reject and cycle slip detection are carried out, error models of ephemeris, tide, relativity, the earth rotation, atmosphere and antenna phase deviation are corrected; an ionospheric virtual observation model with additional ionospheric prior information constraints, spatial domain constraints and time domain constraints is constructed; and a three-frequency non-differentialnon-combinatorial precise single-point positioning model is constructed, a single-point positioning timing solution is carried out on corrected data, and comprehensive clock corrections of receivers of the two transmission time stations are obtained and compared to obtain a time transmission difference; and compared with standard time of one of the two transmission time stations, precise time of the other one of the two transmission time stations is obtained. According to the Beidou three-frequency non-differential non-combined observation value time transmission system and method, the observation noise can be reduced, and the accuracy and reliability of time transmission are improved.

The invention discloses a global satellite navigation system multimode radio frequency receiving method and apparatus for military and civil use, pertaining to the radio frequency communication technique field. The method provides a frequency programming in which the different narrowband signals are as mutual mirror-images of a mirror-image inhibition receiver, according to the civil narrowband signals passing through the mirror-image inhibition receiver, under the control of a time division multiplexing control system, the local oscillation frequency input from a frequency synthesizer to a radio-frequency frequency mixer and baseband frequency mixer can be periodically switched, thereby realizing the multimode paralleling receiving of the narrowband signals; while the broad band signals pass through a direct lower frequency conversion receiver, selecting a local oscillation frequency of the radio-frequency frequency mixer identical to the center frequency of the wideband GNSS, thereby realizing the receiving of each wideband mode signal for military use; the apparatus includes a mirror-image inhibition receiver and a direct lower frequency conversion receiver. The invention implementing compatibility and coordinating performance for military and civil use, and also can close the military or civil passage way for implementing the low-power consumption application requirement.

The invention relates to a maritime navigation rescue system based on a Beidou satellite. The system utilizes the specific short message communication function of the Beidou satellite navigation system, after a ground command and control center receives a distress message sent by a ship, the short message communication function of the Beidou satellite navigation system can be used for getting in touch with the ship in distress, the authenticity of the distress message is confirmed, and false alarms are greatly reduced. Meanwhile, a ship-mounted terminal of the system is free from restrictions of external factors of distance, weather, sea conditions and the like due to the short message communication function of the Beidou satellite navigation system, and has functions of actively sending position information of the ship in distress at any time and conducting short message communication with the ground command and control center at any time. The ship-mounted terminal is stable and effective, can accurately and timely send distress messages, and is helpful for ground staff to position and track people in distress, and thus the rescue speed is accelerated. Furthermore, compared with existing ships with mutually-independent navigation systems and rescue equipment, the ship-mounted terminal of the system has functions of navigation and rescue at the same time.

This invention relates to the field of Inertial Navigation Systems (INS) and satellite navigation systems such as the Global Positioning System (GPS) and in particular relates to methods of integrating GPS and INS data in order to provide more accurate navigation solutions. The invention provides a method of improving the accuracy of a tightly coupled integrated INS and satellite radio navigation system in cases where the satellite navigation receiver has adaptive tracking loop bandwidths.

Low-energy consumption techniques for locating a movable object using a global satellite navigation system (GNSS) are provided. A mobile station attached to or included in a movable object can communicate bidirectionally with a fixed base station to determine a location of the movable object. The mobile station may communicate an estimated position to the base station and receive from the base station a set of GNSS satellites that are visible to the mobile station. The mobile station can acquire satellite timing information from GNSS signals from the set of satellites and communicate minimally-processed satellite timing information to the base station. The base station can determine the position of the mobile station and communicate the position back to the mobile station. By offloading much of the processing to the base station, energy consumption of the mobile station is reduced.

The invention discloses a low-power-consumption indoor and outdoor positioning method which comprises the steps of arranging positioning beacons such as a Bluetooth device in a required indoor environment; after a receiving end receives positioning information, performing low-power-consumption transmission of the positioning information to a background monitoring system by means of LPWAN technology, finishing indoor positioning by the background monitoring system, and simultaneously, performing positioning at an outdoor space by means of a satellite navigation system, transmitting a latitude-and-longitude result which is output from the satellite navigation system back to the background monitoring system through the LPWAN, thereby realizing omnibearing positioning in the indoor space and the outdoor space. The low-power-consumption indoor and outdoor positioning method overcomes problems of high cost and high power consumption. Furthermore on the condition that a sensor senses a fact that a person or an article does not move, the sensor automatically enters a dormancy state, thereby effectively prolonging duration time and standby time and greatly improving actual popularization value.

The invention provides a train combined positioning method under a condition of a limited satellite signal. The method can revise bias of an inertial navigation system by using position information provided by a satellite navigation system under the condition of effective satellite positioning, combines train gesture information with output parameter of a wheel sensor, calculates to obtain three-dimensional speed under a navigation coordinate system and reserves information of satellite unlocking. Under the condition of satellite positioning failure, a wheel sensor / inertial navigation systemis applied to combine and position; a wheel sensor is applied to revise the bias of the inertial navigation system, thus the train combination navigation system can provide positioning information with a certain precision. A high-precision digital track map is used for revising the bias of the train on the track vertical direction, thus the positioning precision of the train is guaranteed. The method can solve the positioning problem of the failure zone of the satellite signal, and carry out system independent switching under different satellite positioning conditions, thus the continuous, exact and reliable train position information can be acquired.

The invention discloses a Beidou / GPS combination based safe train locating method and system. A Beidou satellite navigation system is combined with a GPS satellite navigation system, a ground differential station system, a train-mounted speedometer and a ground responder system are combined in use, and safe location of a train is realized. The system of the invention can coexist and be compatiblewith existing train locating systems, and satellite navigation is safer in the aspect of train locatin.

The combined navigation system for aviation consists of inertia navigation system, satellite navigation system, VOR-DME and altimeter. After fault diagnosis to judge the normality and the availability of the separate navigation systems, the normal navigation systems are combined to form one multistage multi-layer structure. By means of information fusion, high precision navigation information is obtained from the combined navigation system. In case of some navigation system with fault, the failed navigation system is isolated and the system is reconstructed for further navigation. The present invention can raise the reliability and availability of the combined navigation system for aviation.