Abstract: An antenna device for a wireless device has a transmitter and an antenna. The first connecting end of the transmiter is connected to the first end of the antenna, and the second connecting end of the transmitter is connected to the second end of the antenna. As a result, the antenna device can be formed as a loop and generates a magnetic field for remotely coupling the wireless device to other devices which can receive the signal emitted from the wireless device. The antenna device also includes a resonating and matching circuit coupled to the transmitter or the receiver.

Abstract: An apparatus is provided for the wireless capture of coordinate-shift information. The apparatus includes a pulse generator that generates a pulse signal and simultaneously distributes the pulse signal into a first signal along the first path and a second signal along the second path. The apparatus further includes a working area defined by a plurality of crossing X-axis signal lines and Y-axis signal lines, and at least one coil surrounding the working area for generating a magnetic field. The apparatus also includes a scanning circuit coupled to the working area, and a synchronic determination circuit coupled to the pulse generator and the scanning circuit for receiving the first and second signals, and for determining the time delay between the receipt of the first and second signals. The apparatus further includes a signal processing circuit coupled to the scanning circuit and the synchronic determination circuit.

Abstract: An antenna device for a wireless device has a transmitter and an antenna. The first connecting end of the transmiter is connected to the first end of the antenna, and the second connecting end of the transmitter is connected to the second end of the antenna. As a result, the antenna device can be formed as a loop and generates a magnetic field for remotely coupling the wireless device to other devices which can receive the signal emitted from the wireless device.

Abstract: A wireless cursor control system is provided that includes a pointing device and a receiver. The pointing device has a controller for receiving user input and for providing a control signal, and a transmitter that includes an antenna and a high frequency modulator coupled to the controller for receiving the control signal and for generating an output signal for transmission via the antenna. The high frequency modulator includes a variable frequency modulator circuit for selectively changing the frequency deviation of the control signal, and a high frequency circuit for increasing the frequency deviation of the control signal to produce the output signal. The receiver has an antenna that receives the output signal, and a demodulation circuit for demodulating the received output signal.

Abstract: A four-stage phase demodulation low frequency wireless mouse device is disclosed, improving a shortcoming of a conventional low frequency wireless mouse device which can not effectively overcome the signal interference and prevent the misoperations by only using I and Q axes or a quadrature demodulation method and the present invention installs a phase demodulation circuit on a receiving end for generating four sets of phase signals each having a phase of 0.degree., 90.degree., 180.degree. and 270.degree. respectively. Then, each of the quadrature signals is sent into a microprocessor for processing to become a computer interfacing signal after passing through a low pass filter, a detecting circuit and a voltage comparator respectively so that the signal interference is effectively eliminated, the misoperation is obviated and the reaction speed of the signal is enhanced due to a low error rate.