2473 results about "Positioning equipment" patented technology

A lithographic apparatus comprises a substrate table to hold a substrate, a reference structure and a measurement system to measure a position of the substrate table with respect to the reference structure. The measurement system comprises a first measurement system to measure a position of the substrate table with respect to an intermediate structure and a second measurement system to measure a position of the intermediate structure with respect to the reference structure. The intermediate structure may be connected or connectable to a drive mechanism to drive the substrate table. A distance between the substrate table and the intermediate structure, and a distance between the intermediate structure and the reference structure may be small which results in a highly accurate position measurement.

A system for facilitating handoff adapted for use with a telecommunications network. The system includes position equipment for determining the location of a mobile transceiver within a region containing a first cell and a second cell. A comparison circuit compares the location with a predetermined handoff area within the region and provides a control signal in response thereto. A handoff initiation circuit initiates handoff of the mobile transceiver between the first cell and the second cell in response to the control signal. In a specific embodiment, the handoff is a hard handoff. The position equipment includes Global Positioning System (GPS) equipment including a mobile unit GPS receiver and signal interface. The comparison circuit includes a positional database that stores latitudinal and longitudinal information corresponding to the predetermined handoff area. The comparison circuit also includes a Code Division Multiple Access selector. The selector begins tracking the position of the mobile transceiver when it is within a predetermined range of the predetermined handoff area. In a specific embodiment, the handoff initiation circuit includes a base station controller. The position equipment includes a base station positional detection system and a mobile unit positional detection system for determining the location of the mobile transceiver. The position database has map information depicting the coverage area of the first and second cells and the predetermined handoff area. The selector runs software for comparing the location to the map information and providing the control signal when the location is within the predetermined handoff area. The base station includes and implements instructions for completing hard handoff in response to the control signal.

An apparatus and method for automatically positioning a device. A sensor detects the position of a user. In response to signals from the sensor, a processor determines an ideal position for use of the device. Next, coordinates for movement of an arm supporting the device and for positioning of the device at an achievable position nearest to the ideal position are calculated, taking into account restraints, such as limitation on the sensors, actuators and motors that move the device, and nearby obstacles such as walls. The arm adjusts to move the device to the achievable position. The device is repositioned at intervals as the user moves. Once no user is detected, then the device is moved to a default position.

A wireless communication system useful in locating users of mobile communication units (MUs) in emergency situations. In one embodiment, the system includes a plurality of aircraft-deployable, wireless position determining equipment (PDE) to generate position information from an emergency call request received from an MU, and a wireless mobile positioning center (MPC) on board an aircraft adapted to determine the location of the MU from the position information received from the PDE. In another embodiment, the PDE are adapted to transmit a message to elicit a response from the MU to acquire position information. In another embodiment, the PDE are adapted to receive periodic messages from the MU to acquire position information. In another embodiment, a mobile switching center (MSC) assists a GPS-capable MU in determining its location by providing it the information on the GPS satellites visible within the area covered by its base station and sector.