摘要:
A wireless repeater that includes a universal server base unit and modular donor antenna options. The universal server base unit includes a base unit bidirectional amplifier, a server antenna, and a housing that accepts an internal donor antenna board or an internal adapter module connected to a cable port for receiving a coaxial cable connected to an external donor antenna. This allows the same universal server base unit to work with a variety of internal and external donor antenna options. In particular, the external donor antennas include outdoor swivel-mounted options including a helical circular polarization antenna, a dual polarization panel antenna, and a vertical polarization panel antenna. The donor antenna may include an optional donor bidirectional antenna located in or near the donor antenna and powered via the cable from the server base unit.
摘要:
A wireless repeater with features that improve the server-donor antenna isolation including multi-purpose server and donor mounting plates that each carry an antenna feed circuit board and associated antenna elements mounted in a back-to-back arrangement with the duplex repeater electronics board sandwiched between the server and donor mounting plates. To improve the server-donor antenna isolation, one or both mounting plates may include corner, side tabs, which may be asymmetric, and raised walls around one or both mounting plates. In addition, the radomes covering the donor antenna and/or the server antennas may carry one or more parasitic conductors, such as a two parasitic strips arranged in parallel lines or for parasitic strips arranged in a square configuration.
摘要:
A wireless repeater that can be remotely controlled and reconfigured, either locally or from a remote control center, after it has been installed in a customer's premises. The reconfigurable parameters and controllable settings include the frequency channel profile for the unit and the associated display profile, frequency channel selection, power level and on-off status, feedback circuit parameters, and system firmware. The communication ports for accessing the functionality of the unit include a wireless transmitter/receiver, such as an on-board wireless telephone chip, and a USB port. Once the unit has been connected to a personal computer through the USB port, the unit can be assigned an Internet IP address and addressed as network node on the Internet.
摘要:
A method for automatically controlling the downhill speed of a machine. The method includes establishing a target machine speed based on a current machine speed and determining whether at least one trigger condition including a grade greater than a predetermined threshold has been satisfied. If satisfied, the method activates a control system to control at least one of a powertrain retarder and a change in a transmission gear to prevent exceeding the target machine speed.
摘要:
Methods and systems for mass spectrometry and more particularly to an interface providing charged particles to a mass spectrometer are described herein.
摘要:
A bearing includes an inner race having a rotational axis and an outer race sharing the rotational axis of the inner race. Rolling bearing members are constrained between the inner race and the outer race. A retention lip is provided which is adapted to maintain a peripheral opening of a constant gauge distance between and prevent relative axial movement of the inner race and the outer race. The gauge distance of the peripheral opening is adapted to allow free passage of the rolling bearing members, upon wear on the rolling bearing members reaches a predetermined level. The bearing provides a pass or fail indication, by falling apart when the rolling bearing members have exceeded the predetermined level of wear.
摘要:
A signature element is attached to a downhole cable or other protected equipment and the signal from a signature position detector is used, at least in part, to control the orientation of a directed perforating device or other directional device. Signal emitting sources can include a radioactive material added to an encapsulating composition of a downhole cable.
摘要:
A lubrication system for a vehicle (100) is provided with a blade element (1) movable between a first position (2) and a second position (3); the lubrication system comprises a pump (4) connected to a reservoir of lubricant and an actuation element or striker (6) acting on the pump (4), the actuation element (6) being activated in response to the blade element (1) when displaced between the first (2) and the second (3) position.
摘要:
A variable load circuit (2) is provided for use with a dimmer (1). A low wattage load such as a LED (3) is provided in series with the dimmer and the variable load circuit is provided in parallel with the LED. The variable load circuit has two different load characteristics: when the applied voltage from the dimmer is below a threshold, the variable load circuit presents a fixed load (24), and when the applied voltage is above a threshold the variable load circuit presents a variable load so as to act as a constant current sink. The variable load is provided by a secondary load portion (25) which may or may not act in combination with the fixed load (24), and the secondary load portion (25) is switched in or out of the variable load circuit by a trigger circuit portion (26).