摘要:
Systems and methods allow for the accurate determination of the terrestrial position of an autonomous vehicle in real time. A first position estimate of the vehicle 102 is derived from satellites of a global positioning system and/or a pseudolite(s). The pseudolite(s) may be used exclusively when the satellites are not in the view of the vehicle. A second position estimate is derived from an inertial reference unit and/or a vehicle odometer. The first and second position estimates are combined and filtered using novel techniques to derive a more accurate third position estimate of the vehicle's position. Accordingly, accurate autonomous navigation of the vehicle can be effectuated using the third position estimate.
摘要:
Systems and methods allow for the accurate determination of the terrestrial position of an autonomous vehicle in real time. A first position estimate of the vehicle 102 is derived from satellites of a global positioning system and/or a pseudolite(s). The pseudolite(s) may be used exclusively when the satellites are not in the view of the vehicle. A second position estimate is derived from an inertial reference unit and/or a vehicle odometer. The first and second position estimates are combined and filtered using novel techniques to derive a more accurate third position estimate of the vehicle's position. Accordingly, accurate autonomous navigation of the vehicle can be effectuated using the third position estimate.
摘要:
Systems and methods allow for the accurate determination of the terrestrial position of an autonomous vehicle in real time. A first position estimate of the vehicle 102 is derived from satellites of a global positioning system and/or a pseudolite(s). The pseudolite(s) may be used exclusively when the satellites are not in the view of the vehicle. A second position estimate is derived from an inertial reference unit and/or a vehicle odometer. The first and second position estimates are combined and filtered using novel techniques to derive a more accurate third position estimate of the vehicle's position. Accordingly, accurate autonomous navigation of the vehicle can be effectuated using the third position estimate.
摘要:
A system (400) for positioning and navigating an autonomous vehicle (310) allows the vehicle (310) to travel between locations. Position information (432) is derived from global positioning system satellites (200, 202, 204, and 206) or other sources (624) when the satellites (200, 202, 204, and 206) are not in the view of the vehicle (310). Navigation of the vehicle (310) is obtained using the position information (432), route information (414), obstacle detection and avoidance data (416), and on board vehicle data (908 and 910).
摘要:
A system (400) for positioning and navigating an autonomous vehicle (310) allows the vehicle (310) to travel between locations. Position information (432) is derived from global positioning system satellites (200, 202, 204, and 206) or other sources (624) when the satellites (200, 202, 204, and 206) are not in the view of the vehicle (310). Navigation of the vehicle (310) is obtained using the position information (432), route information (414), obstacle detection and avoidance data (416), and on board vehicle data (908 and 910).
摘要:
A system (400) for positioning and navigating an autonomous vehicle (310) allows the vehicle (310) to travel between locations. Position information (432) is derived from global positioning system satellites (200, 202, 204, and 206) or other sources (624) when the satellites (200, 202, 204, and 206) are not in the view of the vehicle (310). Navigation of the vehicle (310) is obtained using the position information (432), route information (414), obstacle detection and avoidance data (416), and on board vehicle data (908 and 910).
摘要:
The navigation receiver with coupled-tracking channels is intended for use in radio navigation systems based on trilateration wherein the times of arrival of radio signals transmitted by a plurality of ground- or space-based terminals are measured by a user terminal and utilized by the user terminal in calculating its position and orientation. The coupled-tracking navigation receiver periodically measures carrier phase, carrier frequency, modulation phase, and carrier amplitude for all of the signals arriving at the receiving ports of the receiver and periodically estimates the present values of carrier phase, carrier frequency, and modulation phase for all of the received signals, the estimating process utilizing for each parameter estimate the parameter measurements for a plurality of the received signals properly combined in a statistically appropriate manner by taking into account the relative geometry of the line-of-sight paths, receiver clock time dynamics, and dynamics and motion constraints of the receiver platform, thereby obtaining better performance under poor signal reception conditions and more accurate estimates of carrier phase, carrier frequency, and modulation phase for each of the received signals than independent measurements alone could provide. It follows that these more accurate estimates of the basic signal parameters lead to more accurate estimates of platform position and attitude and the rates of change of these quantities.
摘要:
In a global positioning system (GPS), such as the NAVSTAR/GPS system, wherein the position coordinates of user terminals (14) are obtained by processing multiple signals transmitted by a constellation of orbiting satellites (16), an acquisition-aiding signal generated by an earth-based control station (12) is relayed to user terminals via a geostationary satellite (10) to simplify user equipment. The aiding signal is FSK modulated on a reference channel slightly offset from the standard GPS channel. The aiding signal identifies satellites in view having best geometry and includes Doppler prediction data as well as GPS satellite coordinates and identification data associated with user terminals within an area being served by the control station (12) and relay satellite (10). The aiding signal significantly reduces user equipment by simplifying spread spectrum signal demodulation and reducing data processing functions previously carried out at the user terminals (14).