摘要:
Embodiments of the present invention pertain to methods and systems for communicating information to a roving positioning device. In one embodiment, a cellular communication device, a non-cellular wireless communication device, and a computer networking device for forwarding data packets are coupled with a bus. A request originating from a roving positioning device for a location-specific position correction is received via the non-cellular wireless communication device. A controller coupled with the bus causes the request to be forwarded via the cellular communication device.
摘要:
A method for standard positioning service (SPS) and precise positioning service (PPS) cooperative operation is disclosed. In one embodiment, a positioning signal is received. A PPS data portion of the positioning signal is acquired with PPS receiver. An SPS data portion of the positioning signal is acquired with an SPS receiver. The PPS receiver and the SPS receiver are then communicatively coupled. The PPS data portion from the PPS receiver is then cross-validated with the SPS data portion from the receiver, wherein the cross validation of the PPS data portion and the SPS data portion provides information about the validity of the posiotioning signal.
摘要:
A vehicle fleet management information system (10) for identification of location and direction of movement of each vehicle in the fleet in real-time and automatic communication directly with management offices to report its location and heading, and status of predetermined events in which the vehicle may be engaged. Each fleet vehicle is assigned a unique time slot to transmit its reporting information over a communications network (10) without substantially interfering with transmissions from other vehicles in their own respective time slots.
摘要:
A system for standard positioning service (SPS) and precise positioning service (PPS) cooperative operation is disclosed. In one embodiment, a PPS receiver is utilized to process a PPS data portion of a positioning signal. In addition, an SPS receiver is utilized to process an SPS data portion of the positioning signal. Furthermore, the PPS receiver and the SPS receiver are communicatively coupled such that the PPS data portion from the PPS receiver is cross-validated with the SPS data portion from the SPS receiver thereby corroborating the accuracy of the positioning signal.
摘要:
Methods and apparatus are provided for factorized processing of a set of GNSS signal data derived from signals having at least three carriers. A geometry filter is applied to the set of GNSS signal data using a geometry carrier-phase combination to obtain an array of ambiguity estimates for the geometry carrier-phase combination and associated statistical information. A bank of ionosphere filters is applied to the set of GNSS signal data using a geometry-free ionosphere carrier-phase combination to obtain an array of ambiguity estimates for the ionosphere carrier-phase combination and associated statistical information. At least one bank of Quintessence filters is applied to the set of GNSS signal data using a geometry-free and ionosphere-free carrier-phase combination to obtain an array of ambiguity estimates for the geometry-free and ionosphere-free carrier-phase combination and associated statistical information. At least one code filter is applied to the set of GNSS signal data using a plurality of geometry-free and ionosphere-free code-carrier combinations to obtain an array of ambiguity estimates for the code-carrier combinations and associated statistical information. The resulting arrays are combined to obtain a combined array of ambiguity estimates for all carrier phase observations and associated statistical information.
摘要:
An apparatus and method for efficiently generating a visible line of light (30) on a surface such as a wall or a floor for the purpose of facilitating the layout process used in construction. The apparatus comprises a light beam generator projecting a beam of visible light (26) on a surface. Reference marking elements (34, 36) on the instrument correspond to the light beam's position. One or more level vials may also be included for indicating vertical and horizontal, as well as a magnet for mounting and a reference bracket for a stud-finder instrument.
摘要:
A GPS receiver and method using alternating 'A' and 'B' integration time segments. The polarities of certain GPS data bits are known beforehand and their expected reception times are known. The GPS signal in 10 millisecond 'A' time segments and 'B' time segments is depolarized according to the known polarities. The depolarized GPS signal during an 'A' time period made up of all the 'A' time segments is integrated for providing an 'A' time period magnitude for each code phase. Likewise, the depolarized GPS signal during a 'B' time period made up of all the 'B' time segments is integrated for providing a 'B' time period magnitude for each potential GPS code phase. The strongest of the time period magnitudes is compared to a correlation threshold for selecting a code phase for signal acquisition.
摘要:
Apparatus for measuring surveying parameters, such as distances and angular displacements between survey stations (11, 31), with improved accuracy. The invention combines a differential satellite positioning system (SATPS), available with positioning systems such as GPS and GLONASS, with electromagnetic measurements of distances and optically encoded angles by a conventional electro-optical survey instrument to provide survey measurements that can be accurate to within a few millimeters in favorable situations. The differential satellite positioning system relies upon carrier phse measurements, after removal of certain phase integer ambiguities associated with carrier phase SATPS signals. The SATPS may be retrofitted within the housing of the conventional electro-optical instrument.