Patent ID: 6388656
Filing Date: 2002-05-14
Classification: G06F

Abstract:
A remote position designation system for designating an optional position on a plane at a place remote from the plane comprising:a transmitter unit including transmitters adapted to transmit, as a position signal, signals of the same frequency, but having different phases, in a simultaneous fashion, respectively, said transmitter unit comprising: a switch input unit for outputting an input signal in accordance with a switching operation thereof; a transmitting-end control unit for generating a control signal, based on an output signal from the switch input unit; a clock frequency divider for generating a clock of a predetermined frequency under a control of the transmitting-end control unit; a square wave generating unit for generating square waves respectively having a sine waveform and a cosine waveform in response to the clock generated from the clock frequency divider; a selection unit for receiving the sine and cosine square waves from the square wave generating unit, and outputting a selected one of the received square waves under a control of the transmitting-end control unit; a distribution unit for receiving one of the square waves from the square wave generating unit along with the selected square wave from the selection unit, and outputting the received signals in the form of distributed signals under a control of the transmitting-end control unit; a current amplifying unit for amplifying the distributed signals from the distribution unit; and the transmitters for transmitting frequency signals respectively based on the amplified signals from the current amplifying unit, the transmitters being arranged at upper, lower, left and right positions, respectively; a receiver unit for receiving the signals transmitted from the transmitters of the transmitter unit in the form of a composite signal, amplifying the received composite signal to a saturation level, and conducting a signal processing for the amplified signal to obtain position information associated with a phase shift of the amplified signal from a reference phase; and a control unit for generating a control signal adapted to display a position designated by the position signal from the transmitter unit on a screen, based on the position information from the receiver unit.