×

Transmitter and transmitting method thereof

  • US 9,952,722 B2
  • Filed: 11/10/2014
  • Issued: 04/24/2018
  • Est. Priority Date: 11/08/2013
  • Status: Active Grant
First Claim
Patent Images

1. A transmitter for transmitting an electrical signal to a capacitive touch sensitive device according to a transmitter status in response to a trigger event detected, allowing the capacitive touch sensitive device to analyze the electrical signal in order to obtain the transmitter status and a relative position between the transmitter and the capacitive touch sensitive device, wherein the electrical signal is mixed by signals having a plurality of frequencies, wherein the transmitter comprises a processing module and a sensor module, the sensor module further including an electrical signal detecting module, wherein the trigger event is triggered when the electrical signal detecting module detects an activation electrical signal corresponding to an activation frequency, wherein the processing module is used for generating the transmitter status according to a status within the sensor module, wherein when the trigger event is detected the transmitter begins transmitting the electrical signal, and when a period of time has elapsed since the trigger event is detected, the transmitter stops transmitting the electrical signal, wherein the electrical signal detecting module further includes at least one of a first demodulator, a second demodulator and a third demodulator for detecting the activation electrical signal, wherein the first demodulator includes:

  • a signal generator for generating an in-phase signal and an orthogonal signal, wherein the frequency of the in-phase signal and the orthogonal signal is the activation frequency;

    at least a mixer for mixing the in-phase signal with a received signal to generate an in-phase analog signal, and mixing the orthogonal signal with the received signal to generate an orthogonal analog signal;

    at least an integrator for performing integration on the in-phase analog signal to generate an in-phase integration signal, and performing integration on the orthogonal analog signal to generate an orthogonal integration signal;

    at least a squarer for calculating the square of the in-phase integration signal and the square of the orthogonal integration signal; and

    at least one “

    Root Mean Square (RMS) of Sum”

    element for calculating the root mean square of the sum of the square of the in-phase integration signal and the square of the orthogonal integration signal to obtain a signal strength corresponding to the activation frequency, and wherein the second demodulator includes;

    an analog-to-digital converter (ADC) for performing analog-to-digital conversion on a received signal to produce a digital received signal;

    a signal generator for generating an in-phase signal and an orthogonal signal, wherein the frequency of the in-phase signal and the orthogonal signal is the activation frequency;

    at least a mixer for mixing the in-phase signal with a received signal to generate an in-phase analog signal, and mixing the orthogonal signal with the received signal to generate an orthogonal analog signal;

    at least an addition integrator for performing addition integration on the in-phase analog signal to generate an in-phase integration signal, and performing addition integration on the orthogonal analog signal to generate an orthogonal integration signal;

    at least a squarer for calculating the square of the in-phase integration signal and the square of the orthogonal integration signal; and

    a “

    Root Mean Square (RMS) of Sum”

    element for calculating the root mean square of the sum of the square of the in-phase integration signal and the square of the orthogonal integration signal to obtain a signal strength corresponding to the activation frequency, wherein the third demodulator includes;

    an analog-to-digital converter (ADC) for performing analog-to-digital conversion on a received signal to produce a digital received signal; and

    a Fourier transformer for performing Fourier transform on the digital received signal to generate a signal strength corresponding to the activation frequency.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×