Patent classifications
G01S19/115
Trilateration-based satellite location accuracy for improved satellite-based geolocation
The present disclosure relates generally to satellite communication systems, and, more particularly, to trilateration-based satellite location accuracy for improved satellite-based geolocation are provided. In one embodiment, a method comprises: determining, by a processing device, a location of each of a plurality of reference antennas with known locations; obtaining a plurality of distances between a communication satellite and the plurality of reference antennas, each distance of the plurality of distances corresponding to a respective reference antenna of the plurality of reference antennas, at least one distance of the plurality of distances based on an echo message communicated between a particular reference antenna of the plurality of reference antennas and the communication satellite; determining an accurate location of the communication satellite based on trilateration of the plurality of distances from the known locations of the plurality of reference antennas; and utilizing the accurate location of the communication satellite.
Precise point position and real-time kinematic (PPP-RTK) positioning method and device
A precise point position and real-time kinematic (PPP-RTK) positioning method, including: when direct emission signals broadcast by a multi-system navigation satellite and a low-earth-orbit constellation are detected, determining raw observation data (S11); receiving navigation satellite augmentation information broadcast by the low-earth-orbit constellation, and a low-earth-orbit satellite precise orbit and precise clock difference (S12); using the navigation satellite augmentation information, the low-earth-orbit satellite precise orbit and precise clock difference and the raw observation data for precise point positioning (S13); or when comprehensive ground-based augmentation error correction information is received, using the navigation satellite augmentation information, the low-earth-orbit satellite precise orbit and precise clock difference, the raw observation data and the comprehensive ground-based augmentation error correction information for precise point positioning of ground-based augmentation (S13′). The present application further relates to a precise point position and real-time kinematic (PPP-RTK) positioning device, a computer-readable storage medium and a processor.
RADIO FREQUENCY (RF) RANGING IN PROPAGATION LIMITED RF ENVIRONMENTS UTILIZING AERIAL VEHICLES
The embodiments described herein provide ranging and location determination capabilities in RF-opaque environments, such as a jungle, that preclude the use of Global Positioning System (GPS) and/or laser ranging systems, utilizing transponders and Global Positioning System (GPS) receivers located on aerial vehicles. The aerial vehicles operate above the RF-opaque environment, and communicate with a ranging device within the RF-opaque environment on frequencies that propagate in the RF-opaque environment. The ranging device transmits RF signals to the transponders, which are received by the transponders and re-broadcasted back to the ranging device on a different frequency. The aerial vehicles also provide their coordinates to the ranging device using their GPS receivers. The ranging device uses information about the transmitted and received RF signals and the GPS coordinates of the aerial vehicles to calculate a perpendicular distance to a property line from the ranging device, and/or to calculate a coordinate location of the ranging device.
INTERFEROMETRY-BASED SATELLITE LOCATION ACCURACY
According to one or more embodiments herein, interferometry-based satellite location accuracy is provided. In one embodiment, a method comprises: determining, generally at a substantially given time, a reference satellite having a known accurate location within angular proximity of a communication satellite having a known general location; determining an accurate angular position of the communication satellite with relation to the reference satellite from the perspective of at least one ground station antenna of a known accurate location; determining an additional location reference measurement of the communication satellite; determining an accurate location of the communication satellite at the substantially given time based at least in part on the accurate angular position of the communication satellite with relation to the reference satellite from the perspective of the at least one ground station antenna and the additional location reference measurement of the communication satellite; and utilizing the accurate location of the communication satellite.
Fast and precise positioning method and system
The present application provides a fast and precise positioning method and system. The method includes: acquiring observation data of navigation satellites and LEO augmentation satellites at a current epoch; respectively acquiring navigation telegrams of the navigation satellites and the LEO augmentation satellites, and obtaining precise orbit and clock bias; correcting errors received in the positioning process according to the acquired navigation telegrams; normalizing by taking a type of satellite navigation system as reference to obtain unified linear observation equations, and calculating observation values of positioning and velocity measurement parameters; calculating estimated values of positioning and velocity measurement parameters at the current epoch through a state equation according to the calculated observation values of positioning and velocity measurement parameters and estimated values of positioning and velocity measurement parameters at the previous epoch; generating and saving positioning and velocity measurement results at the current epoch according to the estimated values of positioning and velocity measurement parameters.
Satellite echoing for geolocation and mitigation of GNSS denial
Satellite echoing for geolocation and mitigation of Global Navigation Satellite System (GNSS) denial are provided herein, where an example method comprises: transmitting an initiated message to a communication satellite along a communication path that has a target device with an unknown distance to the communication satellite; receiving a returned message from the communication satellite over the communication path in response to the initiated message; determining a local time difference between the transmission time and the reception time; calculating a distance between the communication satellite and the target device, the distance calculated based on a portion of the determined time difference associated with only a single traversal of a portion of the communication path that is between the communication satellite and the target device; and performing one or more actions based on the distance between the communication satellite and the target device.
SPURIOUS SPACE VEHICLE DETECTION VIA EXPLOITING KNOWLEDGE OF KNOWN BITS
A system and a method are disclosed for detecting a spurious signal in a Global Navigation Satellite System (GNSS) receiver. A detector of the GNSS receiver determines a first sequence of known bits or known-bit transitions of a space vehicle (SV) signal of a target SV. A second sequence is determined based on a coherent sum of the SV signal being tracked by the GNSS receiver. A first reliability sequence may be associated with the first sequence, and a second reliability sequence that may be associated with the second sequence. A correlation statistic of the first sequence is determined based on the second sequence. Whether the first SV signal is a spurious signal is determined based on a comparison of the correlation statistic to a threshold value.
Positioning device and positioning method
A positioning device receives multiple positioning signals respectively transmitted from multiple positioning satellites, changes a condition of the positioning satellites to be used in a positioning calculation processing based on a determination of whether a surrounding environment is an environment in which a multipath is likely to occur, and performs the positioning calculation processing by using the positioning signals from the positioning satellites that satisfy the condition.
Location of a moving target with round trip time vectors using an airborne platform
A method and devices are disclosed that locate a target station moving at a constant velocity. A method and devices are disclosed for producing an RTT vector that is based upon the changes in position of the airborne measuring station position and the relative change in position of the target station. In one embodiment, the target station is an access point or station conforming to the IEEE 802.11 Standard and the airborne measuring station may also be a device that conforms to the IEEE 802.11 Standard.
RADIO FREQUENCY (RF) RANGING IN PROPAGATION LIMITED RF ENVIRONMENTS UTILIZING AERIAL VEHICLES
The embodiments described herein provide ranging capabilities in RF-opaque environments, such as a jungle, that preclude the use of Global Positioning System (GPS) and/or laser ranging systems, utilizing transponders and Global Positioning System (GPS) receivers located on aerial vehicles. The aerial vehicles operate above the RF-opaque environment, and communicate with a ranging device within the RF-opaque environment on frequencies that propagate in the RF-opaque environment. The ranging device transmits RF signals to the transponders, which are received by the transponders and sent back to the ranging device on a different frequency. The aerial vehicles also provide their coordinates to the ranging device using their GPS receivers. The ranging device uses information about the transmitted and received RF signals and the GPS coordinates of the aerial vehicles to calculate a distance to a property line from the ranging device, and/or to calculate a coordinate location of the ranging device.