Abstract: A system for detecting the presence of a plant on the ground includes a light module configured to emit a light beam having a shape with a length longer than a width. The system may include one or more lenses each having one or more photodetectors. The photodetectors may be arranged in a side-by-side configuration and are configured to receive reflected portions of the light beam. The lenses may be configured to direct the reflected portions of the light beam onto the photodetectors.

Abstract: A plant detection system includes a radiation module and a photodetector system. The photodetector system includes a photodetector housing, one or more photodetectors, a detector lens, and an aperture plate. The aperture plate is disposed within the photodetector housing between the detector lens and the one or more photodetectors and has an aperture extending therethrough. The detector lens and the aperture plate are configured so that stray radiation received by the detector lens is directed through the aperture in the aperture plate or onto a surface of the aperture plate without being directed onto sidewalls of the photodetector housing.

Abstract: A Light Emitting Diode (LED) is added to a weed control system for calibrating the weed control system. A detector generates an electrical signal based on receiving light emitted by the LED. An electronically-tunable capacitor of a bandpass filter is adjusted based the signal received from the detector to adjust a center frequency of the bandpass filter so that light from an optical source, different from the LED, can more efficiently be detected by the weed control system.

Abstract: A plant detection system includes a radiation module and a photodetector system. The photodetector system includes a photodetector housing, one or more photodetectors, a detector lens, and an aperture plate. The aperture plate is disposed within the photodetector housing between the detector lens and the one or more photodetectors and has an aperture extending therethrough. The detector lens and the aperture plate are configured so that stray radiation received by the detector lens is directed through the aperture in the aperture plate or onto a surface of the aperture plate without being directed onto sidewalls of the photodetector housing.

Abstract: A Light Emitting Diode (LED) is added to a weed control system for calibrating the weed control system. A detector generates an electrical signal based on receiving light emitted by the LED. An electronically-tunable capacitor of a bandpass filter is adjusted based the signal received from the detector to adjust a center frequency of the bandpass filter so that light from an optical source, different from the LED, can more efficiently be detected by the weed control system.

Abstract: Methods for controlling a plant detection system include determining a target phase delay based on a first phase delay of reflected portions of a first light beam and a second phase delay of reflected portions of a second light beam. A composite light beam comprising the first light beam and the second light beam is emitter towards bare soil, and reflected portions of the composite light beam are detected. An intensity of at least one of the first light beam or the second light beam is adjusted so that a phase delay of the composite light beam is approximately equal to the target phase delay.

Abstract: Methods for controlling a plant detection system include determining a target phase delay based on a first phase delay of reflected portions of a first light beam and a second phase delay of reflected portions of a second light beam. A composite light beam comprising the first light beam and the second light beam is emitter towards bare soil, and reflected portions of the composite light beam are detected. An intensity of at least one of the first light beam or the second light beam is adjusted so that a phase delay of the composite light beam is approximately equal to the target phase delay.

Abstract: A system for detecting the presence of a plant on the ground includes a light module configured to emit a light beam having a shape with a length longer than a width. The system may include one or more lenses each having one or more photodetectors. The photodetectors may be arranged in a side-by-side configuration and are configured to receive reflected portions of the light beam. The lenses may be configured to direct the reflected portions of the light beam onto the photodetectors.

Abstract: A projected capacitive touch sensor system includes a substrate that defines a plurality of non-overlapping areas. Each non-overlapping area includes a plurality of detection electrodes arranged in non-overlapping columns. The columns include a horizontal detection electrode that extends along substantially an entire height of a first column, and at least a second column of at least two vertical detection electrodes that are electrically isolated from one another. The system further includes a measuring circuit configured to measure a mutual capacitance between the horizontal detection electrode and each of the at least two vertical detection electrodes in a given area. A processing logic circuit of the system is configured to determine horizontal detection electrode and vertical detection electrode combinations that have a changed mutual capacitance.

Abstract: Sugar cane yield mapping improves the efficiency of sugar cane farming with benefits to both sugar producers and consumers.

Abstract: Sugar cane yield mapping improves the efficiency of sugar cane farming with benefits to both sugar producers and consumers.

Abstract: A projected capacitive touch sensor system includes a substrate that defines a plurality of non-overlapping areas. Each non-overlapping area includes a plurality of detection electrodes arranged in non-overlapping columns. The columns include a horizontal detection electrode that extends along substantially an entire height of a first column, and at least a second column of at least two vertical detection electrodes that are electrically isolated from one another. The system further includes a measuring circuit configured to measure a mutual capacitance between the horizontal detection electrode and each of the at least two vertical detection electrodes in a given area. A processing logic circuit of the system is configured to determine horizontal detection electrode and vertical detection electrode combinations that have a changed mutual capacitance.

Abstract: A radio frequency identification exciter (200) includes a plurality of antenna elements (122a-i) that are spaced to define active areas (130a-e). A matrix switch (202) flexibly connects the plurality of antenna elements to an exciter circuit (203). Independent switches (204a-i) are selectively switched such that an electric field is generated between at least two antenna elements whereby radio frequency identification tags (132) in the vicinity of the two antenna elements are capacitively powered to exchange data with the exciter. Antenna elements other than the at least two antenna elements may be selectively coupled to a signal from the exciter circuit that inhibits activation of radio frequency identification tags in the vicinity of those antenna elements. The matrix switch preferably comprises polymer-based circuits.

Abstract: A radio frequency identification (RFID) device (12) having displacement current control. The RFID device (12) comprises a voltage source (30), and exciter electrode, electronic circuitry, a displacement current control surface (74) and a dielectric. The voltage source has a current return node. The exciter electrode is coupled to the voltage source. The displacement current control surface (74) is placed between the exciter electrode and the electronic circuitry. The dielectric is positioned between the displacement current control surface and the electronic circuitry, wherein the displacement current control surface is electrically terminated to the current return node of the voltage source.