Abstract: An outdoor satellite receiving unit (ODU) receives several independent satellite signals, selects two signals with a switch matrix, downconverts the two signals to a bandstacked signal with a high and a low band signal, and outputs the bandstacked signal on the same cable to receiver units. Several satellite signals can be selected in groups of two or more and output to independent receiver units. Signal selecting is performed at the received radio frequency (RF) and bandstacking is performed with a single downconversion step to an intermediate frequency (IF). Channel stacking on the same cable of more than two channels from several satellites can be achieved by using frequency agile downconverters and bandpass filters prior to combining at the IF output. A slow transitioning switch minimizes signal disturbances when switching and maintains input impedance at a constant value.

Abstract: A test and measurement instrument for extracting waveforms from a differential transmission line without disrupting the differential transmission line. The test and measurement instrument includes a first input configured to receive a voltage waveform from a voltage probe electrically coupled to the first and second lines of the differential transmission line that electrically connect a first device and a second device, a second input configured to receive a current waveform from a current probe coupled to the differential transmission line, and one or more processors configured to receive the voltage waveform and the current waveform and determine a voltage of the first device and a voltage of the second device based on the voltage waveform and the current waveform.

Abstract: Disclosed is a method for estimating tension of a chain of a scraper conveyor, belonging to a method for estimating chain tension. The method comprises the following steps: embedding strain sensors in a plurality of scrapers of a scraper conveyor to measure the tension of weak coupling points between the scrapers and chains, converting acquired sensor signals into data signals through an A/D conversion unit, transmitting the data signals to a data control center using a wireless transmission module, further processing the tension data information of the weak coupling points through the data control center, establishing a chain tension distribution model, and determining an the estimated tension of the chain of the scraper conveyor. The method provided by the present invention is simple, efficient and practical, and the estimation of tension of the whole continuous moving chain is completed by the tension measurement at limited positions of the chain.

Abstract: A method includes measuring tensions on a measuring wire coupled to a displacer of a servo gauge. The servo gauge is configured to raise and lower the displacer using a drum around which the measuring wire is wound. Different measured tensions are associated with different segments of the measuring wire. The method also includes calculating or adjusting a measurement associated with material in a tank using the measured tensions to account for a change in a length of the measuring wire. Calculating or adjusting the measurement could include calculating one or more first length adjustments for one or more segments of the measuring wire that are wound around the drum, calculating one or more second length adjustments for one or more other segments of the measuring wire that are unwound from the drum, and combining the first and second length adjustments to identify a final length adjustment.

Abstract: A system for driving a multi-stage LED with low distortion and with current proportional to rectified input voltage is disclosed. In an exemplary embodiment, an apparatus includes LED groups connected in series to form an LED string having a first node, a last node, and intermediate nodes. The apparatus also includes current cells having inputs coupled to the nodes and outputs coupled to an output resistor. Each current cell selectively regulates current to flow between its respective input and the output resistor. The apparatus also includes a feedback circuit that generates a plurality of feedback voltages from a voltage level at the output resistor. When a selected current cell is enabled by a selected feedback voltage to regulate a selected current level from its respective input to the output resistor, upstream current cells are disabled by their respective feedback voltages.

Abstract: A power supply extracts electrical power from the electro-magnetic field surrounding a high voltage power conductor and conditions the derived input power to provide a stable power source for instrumentation and communications equipment. The communications controller is a local network router that routes serial data traffic to selected communication devices such as an instrumentation processor, a power supply processor, or a maintenance port controller. The router forwards the data to other communications equipment and forwards data from the communicating equipment to an external network providing substantially simultaneous communications between the external network and the instrumentation processor, power supply processor and maintenance port controller.

Abstract: One embodiment of the present invention provides a system that dynamically adjusts data resolution during proactive-fault-monitoring in a computer system. During operation, the system temporarily stores high-resolution data for a telemetry signal from the computer system in a buffer. The system then generates low-resolution data for the telemetry signal from the high-resolution data. Next, the system monitors the low-resolution data, and while doing so, determines if an anomaly exists in the low-resolution data. If an anomaly exists in the low-resolution data, the system records the high-resolution data from the buffer on a storage device.

Abstract: This invention relates to data communication equipment (DCE), more specifically, high speed transmission of electronic data between data terminal equipment (DTE). The invention sets forth a method and a device for transmitting a voltage signal waveform as a series of current pulses onto, for instance, a communication line. The method requires converting an input voltage signal waveform to a current signal waveform and transmitting the resulting current pulses onto a communication line wherein a predetermined bias voltage is maintained.

Abstract: An automobile radio telephone apparatus capable of detecting a drop of power source voltage to prevent a telephone channel from being occupied wastefully and to thereby enhance efficient use of channels with regard to the operation of an automobile radio telephone system. When the power source voltage is lower than a predetermined voltage, the apparatus informs the user of such an occurrence. On the lapse of a predetermined period of time and if a conversation is under way, the apparatus warns the user that it will execute a forcible conversation ending procedure and then executes it.