Abstract: Method of demodulation of M-CPFSK signal, includes receiving the M-CPFSK radio signal; moving it to zero frequency; sampling at no less than double a frequency of symbols; storing the samples with their amplitude and phase for at least L4 symbols; demodulating the sampled signal in three stages, wherein each stage includes iterating over symbol values within a block of symbols, of length is L1, L2 and then L3; in the first stage, N1 symbol sequences out of all possible symbol sequences are iterated over, at the second stage, N2 symbol sequences out of all possible symbol sequences are iterated over, and at the third stage, N3 symbol sequences out of all possible symbol sequences are iterated over, to obtain final symbol values; symbol values obtained at previous stage is used in a next stage to reduce a number of symbol sequences; and determining encoded bits based on final symbol values.

Abstract: A method of receiving two chip-by-chip multiplexed CSK signals (e.g., GNSS signals) and searching for a non-CSK signal with optimal performance at a given digit capacity of a sampling memory resided in parallel correlators. For CSK signals Prompt, Early and Late results for each of possible code shift are calculated as different sums of four punctured convolutions. Depending on configuration, the method allows to receive both multiplexed CSK signals with lesser quality or one of the CSK signals with better quality. The method can be implemented as an apparatus with four punctured correlators, a set of multipliers by 1 or 2N, another set of multipliers by 1 or 0, summers of four input to one result, a RAM, searchers of maximum, and conditional commutators.

Abstract: A method and apparatus for fast searching GNSS signals performed on a GNSS receiver includes the steps of receiving a signal having a known pseudo random noise code. State information of a code generator is stored when a pseudo random noise code is generated. Several NCO, including a Doppler NCO are used to search GNSS signal for several supposed Doppler’s simultaneously. A search window associated with the received signal is reviewed a first time to identify a source of the received signal. After it is determined if a source of the received signal can be identified, the state information is loaded into the code generator prior to reviewing the search window a second time etc. Search windows is shifting by all length PRN Code. The loading of state information allows sequential review of the search window without readjustment of a fast search module which speeds the process of analyzing the received signals.

Abstract: An antenna comprising a ground plane, a composite radiation patch, and an excitation circuit is described herein. The composite radiation patch is disposed on a printed circuit board and comprises a conducting plate and a plurality of conductive strips. The composite radiation patch comprises an outer region and an inner region separated by a circle of a given radius. The conducting plate comprises 1) a first set of arcuate slots disposed on the circle and 2) a second set of slots each contacting an external perimeter of the conducting plate at one end and a corresponding slot of the first set of arcuate slots at another end. The plurality of conductive strips is disposed within the outer region of the composite radiation patch, with one or more of the plurality of conductive strips galvanically contacting the conducting plate. The excitation circuit is disposed on the printed circuit board for exciting a right hand circularly polarized wave.

Abstract: An apparatus for forming wideband pseudo random noise signals includes a set of channels each comprising an NCO having a controlled frequency and phase and a PRN code generator, the NCO generating a strobe that is output to the PRN code generator. The PRN code generator forms a new sequence element of +1 or ?1 in response to the strobe. The apparatus also comprises a first modulator having a plurality of weight coefficients, a plurality of multipliers each multiplying one of the weight coefficients, an adder outputting a sum of the plurality of multipliers output signals, and a mixer with a quadrature output signal multiplying the adder's output by sine and cosine of a low intermediate frequency. The apparatus also includes a processor controlling the set of channels, a transceiver module to receive and/or transmit quadrature signals, and an interface connecting the output of the mixer and the transceiver module.

Abstract: A method and apparatus for determining the precise location of a target on a surface by utilizing a plurality of objects that are fixed in their position proximate to the location, thereby constituting a plurality of fixed reference points, upon which the target(s) resides or is otherwise located. The plurality of fixed references points are used either in conjunction with images of the target or certain distance measurements between the target and the fixed reference points to determine the precise location of the target(s) on the surface.

Abstract: Method of reducing multipath effects on phase measurements, including receiving radio signals with different pseudo-random codes transmitted by at least four base stations, each at particular frequency received by one channel; measuring delay difference and phase difference from different pairs of base stations; calculating a current position of the receiver based on the measured phase differences and delay differences, wherein the base stations differ in pseudo-random codes at same frequencies or differ in carrier frequency or polarization type if using the same pseudo-random codes, and wherein a number of channels in the receiver exceeds a number of channels needed for the calculating of the current position; detecting anomalous jumps in phase of one or more channels, based on first or second derivative of the phase, as being indicative of multipath signal reception; removing those channels from calculation of current position; and calculating current position based on remaining channels.

Abstract: A laser measuring system comprising a laser transmitter and a laser receiver is provided. The laser transmitter includes one or more laser sources for projecting an initial laser pulse and a reflective surface. The laser receiver includes a first reflective surface for reflecting the initial laser pulse to provide a first reflected laser pulse, and a second reflective surface for reflecting the initial laser pulse to provide a second reflected laser pulse. The laser receiver further includes a photo detection unit for receiving 1) a first double reflected laser pulse produced by the first reflected laser pulse reflecting off the reflective surface of the laser transmitter, and 2) a second double reflected laser pulse produced by the second reflected laser pulse reflecting off the reflective surface of the laser transmitter. The laser receiver determines an orientation angle associated with the laser receiver based on the first and second double reflected laser pulse.

Abstract: Systems and methods for stabilizing a header of a combine harvester are provided. A vertical disturbance signal indicative of a vertical disturbance on the header and a lateral tilt disturbance signal indicative of a lateral tilt disturbance on the header are received from one or more sensors disposed on the header. A compensated vertical displacement value is determined based on the vertical disturbance signal and a compensated lateral tilt displacement value is determined based on the lateral tilt disturbance signal. One or more control signals are transmitted to one or more actuators to vertically displace the header based on the compensated vertical displacement value to compensate for the vertical disturbance and to rotationally displace the header about a pivot joint based on the compensated lateral tilt disturbance signal to compensate for the lateral tilt disturbance.

Abstract: A method for path planning for a machine to traverse an area includes calculating a spline trajectory based on a plurality of control points of a first path. A subset of the plurality of control points having an equal step is selected. A direction of the normal to the spline trajectory for each of the selected points is determined. Control points within the subset that are a solution to a second order cone programming class optimization problem along each normal to the spline trajectory are searched for and the spline trajectory is extended to a border of the area to create a second path adjacent to the first path based on the control points. The optimization problem can minimize the weighted sum of the average curvature at junction points of elementary sections of the spline trajectory and/or the average width overlap of adjacent paths.

Abstract: Determining vehicle orientation based on GNSS signals received by three antennas that are logically combined into two pairs, with one antenna common for both pairs. GNSS receiver measures first carrier phase difference within each pair of antennas, represented as sum of an integer number of periods of the carrier frequency and a fractional part of the period. The fractional parts are used to compute orientation of the vector connecting the antennas phase centers within each pair, excluding integer ambiguity resolution. Vehicle attitude is calculated from the orientation of two non-collinear vectors with a common origin, measured by two pairs of antennas. Each antenna has an RF front end. All RF front ends, heterodynes, digital navigation processors of this receiver are clocked from one common clock oscillator. All carrier phase measurements of the three antennas are performed on a common time scale.

Abstract: Systems and methods for calculating a plant spread and a plant density of vegetation are provided. An ultrasonic signal is transmitted towards vegetation by one or more transducers. A plurality of echo signals is received as reflections of the ultrasonic signal by the one or more transducers. A plant spread of the vegetation is calculated based on a first echo signal of the plurality of echo signals and a last echo signal of the plurality of echo signals. A plant density of the vegetation is calculated based on the plurality of echo signals. The plant spread and the plant density of the vegetation are output.

Abstract: A method of receiving two chip-by-chip multiplexed CSK signals (e.g., GNSS signals) and searching for a non-CSK signal with optimal performance at a given digit capacity of a sampling memory resided in parallel correlators. For CSK signals Prompt, Early and Late results for each of possible code shift are calculated as different sums of four punctured convolutions. Depending on configuration, the method allows to receive both multiplexed CSK signals with lesser quality or one of the CSK signals with better quality. The method can be implemented as an apparatus with four punctured correlators, a set of multipliers by 1 or 2N, another set of multipliers by 1 or 0, summers of four input to one result, a RAM, searchers of maximum, and conditional commutators.

Abstract: A laser measuring system including first and second laser base stations and a laser receiver is provided. The laser receiver detects a first laser signal from the first laser base station. Location information associated with the first laser base station is extracted from the detected first laser signal. The laser receiver detects a second laser signal from the second laser base station. Location information associated with the second laser base station is extracted from the detected second laser signal. A position of the laser receiver is determined based on the extracted location information associated with the first laser base station and the extracted location information associated with the second laser base station.

Abstract: Systems and methods for determining a swing angle of a swing boom of a vehicle are provided. Sensor data is received from sensors disposed on a swing boom and a body of a vehicle. It is determined whether the swing boom is static or moving relative to the body based on the sensor data. In response to determining that the swing boom is static, the received sensor data is corrected based on an observed swing angle and an estimated swing angle is calculated based on the corrected sensor data. In response to determining that the swing boom is moving, the estimated swing angle is calculated based on the received sensor data. The estimated swing angle is output.

Abstract: A self-leveling laser transmitter is provided. The laser transmitter comprises a rotation head and an accelerometer mounted on the rotation head. An acceleration signal is received from the accelerometer and one or more tilt adjustment signals for adjusting a tilt of the rotation head to a leveled orientation are generated based on the acceleration signal. One or more actuators adjust the tilt of the rotation head based on the one or more tilt adjustment signals.

Abstract: An antenna comprising a ground plane, a composite radiation patch, and an excitation circuit is described herein. The composite radiation patch is disposed on a printed circuit board and comprises a conducting plate and a plurality of conductive strips. The composite radiation patch comprises an outer region and an inner region separated by a circle of a given radius. The conducting plate comprises 1) a first set of arcuate slots disposed on the circle and 2) a second set of slots each contacting an external perimeter of the conducting plate at one end and a corresponding slot of the first set of arcuate slots at another end. The plurality of conductive strips is disposed within the outer region of the composite radiation patch, with one or more of the plurality of conductive strips galvanically contacting the conducting plate. The excitation circuit is disposed on the printed circuit board for exciting a right hand circularly polarized wave.

Abstract: A combined cellular/GNSS (global navigation satellite systems) antenna is provided. The combined cellular/GNSS antenna comprises an external area and an internal area delineated by a circumference of a circle. The combined cellular GNSS antenna further comprises a cellular antenna and a GNSS antenna. The cellular antenna comprises a set of cellular radiators disposed in the external area and connected to a cellular feeding network for excitation of the set of cellular radiators. The GNSS antenna comprises radiation elements disposed in the internal area and has a center located substantially at a center of the circle.

Abstract: An earthmoving machine and method for automatically controlling cyclical operations of the earthmoving machine are disclosed. The earthmoving machine includes a plurality of machine elements each controlled by one or more respective actuators. the method comprises: determining a current machine state; calculating control signals for at least one actuator when the current machine state corresponds to a cyclical operation; and transmitting the control signals to the at least one actuator to automatically control the cyclical operation.

Abstract: A vehicular positioning system utilizing multiple optical cameras having contiguous fields of view for reading coded markers having pre-determined positions for determining the position of vehicle inside a structure with a high degree of accuracy. The vehicle positioning system provides for the direct installation and use of a positioning apparatus on a vehicle with a limited number of coded markers to determine the vehicle's position to within millimeter level accuracy.