Abstract: A method and system for leveraging available navigation frequencies for determining position by creating a flexible navigation signal architecture is disclosed. Such an architecture is designed for customizing a navigation system by combining, adding, replacing or removing one or more removable RF section modules. At least one of the RF section modules has a mutually complementary frequency set with respect to a frequency set of one or more of the other RF section modules in the system.

Abstract: A satellite navigation system using multiple antennas for providing the position of multiple fiduciary points on an object even when fewer than four satellites are visible to some or all the antennas. Satellite signals from the multiple antennas are fed into at least one receiver. The receiver or receivers utilize constraint information, which is independent of the satellite signals. These external constraints are used to augment the signals received from the satellites, to obtain the position solution for each antenna. In a preferred embodiment, a common reference clock is used to provide an external constraint. Examples of other external constraints that can be used in the current invention are distance between the antennas, inertial measurement of attitude, rotational or linear position sensors, etc.

Abstract: A set of receiver antennas, of which at least one of the receiver antennas has the capability of receiving frequencies that another receiver antenna from the set is incapable of receiving, is used for determining position and orientation in a navigation system.

Abstract: Troposphere corrections are provided in a land based transmitter-positioning system. Troposphere delays correct ranges based on X- or ISM-band carrier ranging signals with a modulation rate of the code of at least about 30 MHz. Ground based transmitters transmit non-GPS type ranging signals, and the receivers correct for troposphere delays. Troposphere delay corrections are applied to range estimates on each iteration of an iterative position-fix algorithm. Different models of troposphere corrections in a ground based ranging system may be used.

Abstract: Wide area corrections are used substantially continuously. Local area corrections are used once or sparsely. For example, an initial position is determined with local area corrections. Wide area corrections are subsequently used. The initial position information is used in the wide area position determination to limit or avoid delay for convergence. Other sparse uses of local area corrections include verifying or updating positions based on substantially continuous use of wide area corrections.

Abstract: The present invention generally relates to control mechanisms and more specifically to a control mechanism which is adaptable to a steering wheel of a vehicle. Most control mechanisms of auto-piloting systems which must be installed on existing vehicles usually require more specific parts and more expensive installations. The control mechanism according to embodiments of the present invention includes components readily installable into the cabin of an existing vehicle and involves elements sandwiching the steering wheel of the vehicle which are operatively mounted to a motoring assembly actuatable by the user of the vehicle.

Abstract: A differential carrier phase global navigation satellite system (GNSS) receiver with multiple antennas uses multiple GNSS carriers to determine position, which can improve the speed of integer searches, for example. In the system, an estimate of delays associated with the transmission paths between the antennas and receiver for at least one of the GNSS frequencies is stored. Typically, these are measures of the phase delay in the transmission paths for two or more of the GNSS frequencies such as in fractional cycles of the GNSS frequencies. Having this information solves problems associated with using multiple carrier frequencies. While cable delays typically have a fixed time delay, the signal paths for the different frequencies are not completely common—even if they were perfectly matched in time, the number of fractional cycles would still be different. Thus, the number of cycles a radio frequency (RF) signal is delayed is different for different frequencies.

Abstract: A Low Earth Orbiting (LEO) satellite is used for broadcasting differential navigation corrections. Using LEO satellites, the “footprint” of the beam is much smaller than for geosynchronous satellites. Datalink bandwidth requirements are reduced to sufficiently cover an entire footprint area. With a LEO satellite transmitting in multiple beams, these footprints become even smaller. Corrections targeted to such a small area provide local area corrections broadcast from the LEO satellites. Payment, discounts, subsidies or charges are arranged to encourage different entities to own or host base stations, resulting in wide distribution of the network of base stations for use with satellite communications.

Abstract: A global navigation satellite system receiver manufacturer provides functional extensibility to a global navigation satellite system receiver. An application programming interface to the receiver is provided. The interface is public, such as using pubically available software or pubically distributed instructions, for loading on applications or other extensions to the core functionality of the GPS receiver. Other programmers than the manufacturer may add applications to the GPS receiver, avoiding separate devices in a vehicle.

Abstract: To reduce the number of processors and/or displays in mobile equipment, an operating system is emulated in one example. A primary operating system runs on a processor or uses a particular display. The emulated operating system shares the same processor and/or same display. The emulation allows use of applications drafted or written for different operating systems in a common or shared environment. As another example, a virtual terminal function is emulated on a particular device. The particular device interacts with additional sources of information for displaying images on a same display. Using emulated operating systems or virtual terminals, a navigation program is used in a vehicle. An additional program is run on the same processor or shares the same display in the same vehicle at substantially the same time.

Abstract: A Low Earth Orbiting (LEO) satellite is used for broadcasting differential navigation corrections. Using LEO satellites, the “footprint” of the beam is much smaller than for geosynchronous satellites, and therefore data link bandwidth requirements are reduced to sufficiently cover an entire area. With a LEO satellite transmitting in multiple beams, these footprints become even smaller. Corrections targeted to such a small area could have the form of local area corrections (for example, raw measurements taken from a navigation reference station) using the LEO satellites.

Abstract: In a local positioning system, a receiver is adapted for receiving signals from a land-based transmitter. The receiver includes an analog decorrelator for decorrelating the transmitted spread spectrum signals. A down converter connected with an antenna may be spaced away from other portions of the receiver. The down converter down converts received ranging signals and provides them to the remotely spaced receiver portions. A signal line connecting the down converter to the receiver may be operable to transmit any two or more of a reference signal provided to the down converter, the down converted intermediate frequency signals provided to the receiver, and power provided to the down converter. The receiver may be positioned adjacent to or as part of a land-based transmitter. By determining positions of two or more antennas, the location of the associated transmitter is determined.

Abstract: A precise positioning method and system is disclosed wherein at least one ground transmitter is used for transmitting a ranging signal with code modulation. The at least one ground transmitter is configured to receive a signal from at least one satellite and a second ground transmitter. The at least one ground transmitter measures a code phase of the received signals. The measured code phase information is communicated to a rover that is associated with a user. The rover can determine the user's precise position based on the measured code and/or carrier phase information and a clock correction model.

Abstract: A system and method for compensating for changes in relative antenna attitude in a single-receiver position detection system, such as a differential carrier phase GPS system, utilizes sensor input to detect changes in the relative attitude of at least two antennas or an antenna positioner, such as an motorized actuator or operator, that orients or re-orients the antennas to a predetermined orientation. The changes in the detected relative carrier phase due to the right hand circular polarized nature of the carrier signals are thus corrected. In this way, the high positional accuracy associated with kinematic GPS systems, for example, can be achieved even when the system's antennas are not constrained by a common rigid body, for example.

Abstract: A number of solutions for deriving the line bias are disclosed. Some of these solutions utilize signal processing and judicious selection of the frequency plan used in the position detection systems to either enable the derivation of the line bias, or make the measurements insensitive to line bias. In other examples, the present invention utilizes measurement schemes for deriving the line bias and enabling a position detection system to process line bias information in order to find a position solution.

Abstract: A precise positioning method and system is disclosed for allowing an array of ground transmitters to self-survey their relative location at centimeter-level accuracy by transmitting, amongst the ground transmitters in the array, bi-directional ranging signals associated with a wideband code modulation with a chipping rate faster than 30 MHz.

Abstract: A system and method provide for precision guiding of agricultural vehicles along a series of adjacent paths to form rows for cultivating a field. In one aspect of the invention the vehicle is moved along a first path while receiving positioning information from a navigational system (e.g., RTK GPS). This positioning information is stored in a processor and is used by the processor to compute a second path adjacent to said first path by calculating piecewise perpendicular offsets from the first path at multiple locations along the first path. The process is repeated to compute a third and subsequent paths so as to cover the field. Because of the offset process, the field may be covered with paths that have varying curvature along their length, while providing substantially no gaps or overlaps in the coverage of the field.

Abstract: An implement steering system includes at least one sensor for providing an indication of tilt associated with an implement as it traverses along an implement path of travel and at least another sensor for providing an indication of the current position of the implement as it traverses along the implement path of travel. A processor provides an implement drift correction signal in response to the indication of tilt and the indication of current position in order of facilitate correcting the implement path of travel so it corresponds to a desired path of travel, while an implement steering arrangement which is responsive to the drift correction signal causes the implement path of travel to be corrected so it corresponds to the desired path of travel as the implement is pulled through an open field by an implement pulling vehicle.

Abstract: In a local positioning system, augmentation of the land-based system is provided by receiving signals from a GNSS. The signals from the land-based positioning system have a code phase accuracy better than one wavelength of a carrier of the signals from the GNSS. Different decorrelation may be used for signals from a satellite than from a land-based transmitter, such as using a digital decorrelator for signals from the satellite and an analog decorrelator for signals from a land-based transmitter. The receivers may include both a GNSS antenna and a local antenna. The phase centers of the two antennas are within one wavelength of the GNSS signals from each other. The local antenna is sized for operation in the X or ISM-bands of frequencies. The GNSS antenna is a patch antenna where the microwave antenna extends away from the patch antenna in at least one dimension.

Abstract: To provide sub-meter accuracy in a local positioning system, ranging signals with a high modulation rate of code, such as 30 MHz, or more are transmitted. Code phase measurements may be used to obtain the accuracy without requiring relative motion or real time kinematic processing. The ISM or X-band is used for the carrier of the code to provide sufficient bandwidth within available spectrums. The length of codes used is less than or about a longest length across the region of operation, such as less than 15 kilometers in an open pit mine. The spread spectrum codes from different land-based transmitters are transmitted in time slots pursuant to a time division multiple access scheme for an increase in dynamic range. To avoid overlapping of code from different transmitters, each time slot includes or is separated by a blanking period. The blanking period is selected to allow the transmitted signal to traverse a region of operation.