WO2020191585A1 - 信号传输方法、系统、主动笔、触控屏和可读存储介质 - Google Patents

信号传输方法、系统、主动笔、触控屏和可读存储介质 Download PDF

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Publication number
WO2020191585A1
WO2020191585A1 PCT/CN2019/079550 CN2019079550W WO2020191585A1 WO 2020191585 A1 WO2020191585 A1 WO 2020191585A1 CN 2019079550 W CN2019079550 W CN 2019079550W WO 2020191585 A1 WO2020191585 A1 WO 2020191585A1
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Prior art keywords
signal
dsss
circuit
resistor
touch screen
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PCT/CN2019/079550
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English (en)
French (fr)
Inventor
张冠军
唐玲裕
Original Assignee
深圳市汇顶科技股份有限公司
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Application filed by 深圳市汇顶科技股份有限公司 filed Critical 深圳市汇顶科技股份有限公司
Priority to EP19920633.5A priority Critical patent/EP3764203B1/en
Priority to PCT/CN2019/079550 priority patent/WO2020191585A1/zh
Priority to CN201980000474.7A priority patent/CN112074803A/zh
Priority to US17/037,531 priority patent/US11106318B2/en
Publication of WO2020191585A1 publication Critical patent/WO2020191585A1/zh

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    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
    • G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
    • G06F3/033—Pointing devices displaced or positioned by the user, e.g. mice, trackballs, pens or joysticks; Accessories therefor
    • G06F3/0354—Pointing devices displaced or positioned by the user, e.g. mice, trackballs, pens or joysticks; Accessories therefor with detection of 2D relative movements between the device, or an operating part thereof, and a plane or surface, e.g. 2D mice, trackballs, pens or pucks
    • G06F3/03545—Pens or stylus
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
    • G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
    • G06F3/033—Pointing devices displaced or positioned by the user, e.g. mice, trackballs, pens or joysticks; Accessories therefor
    • G06F3/0354—Pointing devices displaced or positioned by the user, e.g. mice, trackballs, pens or joysticks; Accessories therefor with detection of 2D relative movements between the device, or an operating part thereof, and a plane or surface, e.g. 2D mice, trackballs, pens or pucks
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
    • G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
    • G06F3/033—Pointing devices displaced or positioned by the user, e.g. mice, trackballs, pens or joysticks; Accessories therefor
    • G06F3/038—Control and interface arrangements therefor, e.g. drivers or device-embedded control circuitry
    • G06F3/0383—Signal control means within the pointing device
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
    • G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
    • G06F3/041—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
    • G06F3/0416—Control or interface arrangements specially adapted for digitisers
    • G06F3/04162—Control or interface arrangements specially adapted for digitisers for exchanging data with external devices, e.g. smart pens, via the digitiser sensing hardware
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
    • G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
    • G06F3/041—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
    • G06F3/044—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means by capacitive means
    • G06F3/0441—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means by capacitive means using active external devices, e.g. active pens, for receiving changes in electrical potential transmitted by the digitiser, e.g. tablet driving signals

Definitions

  • This application relates to the field of touch technology, and in particular to a signal transmission method, system, active pen, touch screen and readable storage medium.
  • the touch screen can transmit DSSS signals to communicate with the pen end, so as to realize the synchronization between the screen end and the pen end and send commands and other operations. How to correctly receive the DSSS signal sent by the screen has become the key.
  • DSSS signal transmission is usually applied in a radio frequency environment, that is, DSSS signals are sent and received through a high-frequency antenna.
  • the inventor found that due to the impedance and other conditions of the screen sensor itself, the DSSS signal spectrum extension is limited. Therefore, the method of transmitting and receiving DSSS signals through a high-frequency antenna is not suitable for applications where the structure, size, and power consumption are strict. Active pen touch system required.
  • the purpose of some embodiments of this application is to provide a signal transmission method, system, active pen, touch screen and readable storage medium.
  • the touch screen and the active pen transmit DSSS signals through capacitive coupling, which can be well adapted to In active pen touch systems that have strict requirements on structure, size, and power consumption.
  • the embodiment of the application provides a signal transmission method applied to an active pen, including: receiving a DSSS signal sent by the touch screen through a coupling capacitor formed between the active pen and the touch screen; wherein, the DSSS The signal is a signal to be transmitted that has undergone spread spectrum coding; the received DSSS signal is analyzed to obtain the signal to be transmitted.
  • the embodiment of the application provides a signal transmission method applied to a touch screen, including: performing spread spectrum coding on a signal to be transmitted to generate a DSSS signal; and connecting the DSSS signal through a coupling capacitor formed between an active pen and the touch screen The signal is sent to the active pen for the active pen to analyze the received DSSS signal to obtain the signal to be transmitted.
  • An embodiment of the present application also provides an active pen, including: at least one processor; and, a memory communicatively connected to the at least one processor; wherein the memory stores the memory that can be executed by the at least one processor The instruction is executed by the at least one processor, so that the at least one processor can execute the signal transmission method applied to the active pen as described above.
  • An embodiment of the present application also provides a touch screen, including: at least one processor; and, a memory communicatively connected to the at least one processor; wherein the memory stores the memory that can be executed by the at least one processor The instructions are executed by the at least one processor, so that the at least one processor can execute the signal transmission method applied to the touch screen as described above.
  • the embodiment of the application also provides a signal transmission system, including: a touch screen and an active pen; the touch screen is used for spread-spectrum encoding the signal to be transmitted to generate a DSSS signal; the touch screen is also used for The DSSS signal is sent to the active pen through a coupling capacitor formed with the active pen; the active pen is used to analyze the received DSSS signal to obtain the signal to be transmitted.
  • a signal transmission system including: a touch screen and an active pen; the touch screen is used for spread-spectrum encoding the signal to be transmitted to generate a DSSS signal; the touch screen is also used for The DSSS signal is sent to the active pen through a coupling capacitor formed with the active pen; the active pen is used to analyze the received DSSS signal to obtain the signal to be transmitted.
  • the embodiment of the present application also provides a computer-readable storage medium that stores a computer program, and the computer program is executed by a processor to implement the above-mentioned signal transmission method.
  • An embodiment of the present application also provides a chip, including: a pre-amplification circuit, configured to pre-amplify the DSSS signal sent by the touch screen received through the coupling capacitor formed between the active pen and the touch screen, The pre-amplified DSSS signal is output to a hysteresis comparison circuit; the hysteresis comparison circuit is used to restore the pre-amplified DSSS signal, and output the restored DSSS signal to a digital demodulation Circuit; The digital demodulation circuit is used to demodulate the restored DSSS signal.
  • the embodiment of the present application also provides an active pen, including the above-mentioned chip.
  • the embodiment of the application receives the DSSS signal sent by the touch screen through the coupling capacitor formed between the active pen and the touch screen.
  • the DSSS signal is a signal to be transmitted after spread spectrum encoding; the active pen pair receives
  • the DSSS signal is analyzed to obtain the signal to be transmitted.
  • the DSSS signal is transmitted through the coupling capacitor formed between the active pen and the touch screen, which can be well adapted to the touch system.
  • the DSSS spectrum is only up to 1MHz, which does not reach the radio frequency level and the active pen has strict requirements on structure, size, and power consumption. That is, the active pen has a small size in practical applications.
  • the radio frequency antenna transmits DSSS signals, which will limit the size of the radio frequency antenna in the active pen, and thus cannot reach the radio frequency level. Therefore, the use of traditional radio frequency methods to transmit DSSS signals is not suitable for touch control systems.
  • the DSSS signal is transmitted through the coupling capacitor formed between the active pen and the touch screen, which can be well adapted to the transmission of DSSS signals in the touch system, and can also satisfy the structure, size and function of the active pen pair. Strict requirements for energy consumption.
  • parsing the received DSSS signal to obtain the signal to be transmitted specifically includes: pre-amplifying the received DSSS signal through a pre-amplification circuit; and inputting the pre-amplified DSSS signal to a hysteresis comparison circuit , Restoring the pre-amplified DSSS signal through the hysteresis comparison circuit; inputting the restored DSSS signal to a digital demodulation circuit, and restoring the restored DSSS signal through the digital demodulation circuit
  • the DSSS signal is demodulated, the signal to be transmitted is output, and the processing of the pre-amplification circuit, the hysteresis comparison circuit and the digital demodulation circuit in turn is beneficial to accurately demodulate the received DSSS signal, so as to output the signal to be transmitted to achieve Accurate signal transmission between the touch screen and the active pen.
  • first-level pre-amplification circuit only a first-level hysteresis comparison circuit, and a first-level digital demodulation circuit are needed to analyze the received DSSS signal.
  • the circuit structure is simple, the required hardware resources are less, and the Low power consumption, very suitable for use in the interactive system of active pen and touch screen which has strict requirements on circuit size and power consumption.
  • the demodulating the restored DSSS signal by the digital demodulation circuit specifically includes: sampling the restored DSSS signal by the digital demodulation circuit to obtain the original signal. Code signal; bitwise exclusive OR of the original coded signal and the preset autocorrelation demodulation signal; accumulate the result of the bitwise exclusive OR to obtain the accumulated result; according to the accumulated result, restore the The latter DSSS signal is demodulated.
  • the bitwise exclusive OR of the original coded signal and the preset autocorrelation demodulation signal specifically includes: after each B-bit original coded signal is collected, the autocorrelation demodulation signal is shifted backward by 1 bit as a whole
  • said B is the number of bits of the autocorrelation demodulation signal
  • the B-bit original coding signal and the B-bit autocorrelation demodulation signal are XOR bitwise
  • the bitwise XOR The result of OR is accumulated to obtain the accumulation result, specifically: accumulating the result of the bitwise exclusive OR of the B-bit original coding signal and the B-bit autocorrelation demodulation signal to obtain the accumulation result
  • Demodulating the restored DSSS signal is specifically: demodulating the restored DSSS signal according to the comparison result of the accumulation result and a preset threshold, providing a specific
  • the demodulation method is conducive to effective demodulation of the received DSSS signal.
  • the original coded signal includes a first type signal, a second type signal, and a third type signal.
  • the first type signal is the spread spectrum code corresponding to the "0" in the signal to be transmitted
  • the second type signal is the spread spectrum code corresponding to the "1" in the signal to be transmitted
  • the third class signal is a useless signal; if the autocorrelation demodulation signal is the first class signal, the The result of comparing the accumulation result with a preset threshold, demodulating the restored DSSS signal, specifically includes: if it is detected that the accumulation result is less than or equal to the first preset threshold, identifying the original B-bit signal
  • the code signal is a first type signal; if it is detected that the accumulation result is greater than or equal to a second preset threshold, it is identified that the B-bit original coding signal is a second type signal; wherein, the second preset threshold Greater than the first preset threshold; if it is detected that the accumulation result is greater than the first preset threshold and less than the second preset
  • the method further includes: taking the start time of the B-bit original coding signal as the recognized start time of the first type signal; If the detected accumulation result is greater than or equal to the second preset threshold, the method further includes: taking the start time of the collected B-bit original coding signal as the recognized start time of the second type signal, and It is helpful to get the starting time of the parsed signal and realize the timing synchronization between the screen end and the pen end.
  • the first preset threshold is greater than or equal to 0 and less than or equal to B*N/2; the second preset threshold is greater than or equal to B*N/2 and less than or equal to B*N; wherein, The B is the number of bits of the autocorrelation demodulation signal; the N is the sampling frequency at which the digital demodulation circuit samples the restored DSSS signal.
  • a method for setting the first preset threshold and the second preset threshold is provided, so that by comparing the accumulation result of each segment of DSSS signal with the first preset threshold and the second preset threshold set by the above method, Analyze each segment of the DSSS signal more accurately, and then realize the analysis of the completed DSSS signal.
  • the pre-amplification circuit is specifically: a non-inverting amplifying circuit or an inverting amplifying circuit, and two implementation manners of the pre-amplification circuit are provided, making the implementation manners of this embodiment flexible and diverse.
  • the hysteresis comparison circuit is specifically: a same direction hysteresis comparison circuit or a reverse hysteresis comparison circuit, and two implementation modes of the hysteresis comparison circuit are provided, which makes the implementation modes of this embodiment flexible and diverse.
  • the active pen includes a main electrode and a secondary electrode
  • the coupling capacitance formed between the active pen and the touch screen is specifically: the coupling capacitance formed between the main electrode and the touch screen, or the The coupling capacitance formed between the secondary electrode and the touch screen allows the active pen and the touch screen to form a coupling capacitance through multiple implementations.
  • Fig. 1 is a schematic diagram of an application scenario of a signal transmission method according to the first embodiment of the present application
  • Fig. 2 is a flowchart of a signal transmission method according to the first embodiment of the present application
  • FIG. 3 is a schematic diagram of a coupling capacitor formed between the active pen and the touch screen in the first embodiment of the present application;
  • FIG. 4 is a waveform diagram of DSSS spread spectrum coding of "0" and "1" in the first embodiment of the present application;
  • step 202 of the signal transmission method in the first embodiment of the present application is a block diagram of the implementation of step 202 of the signal transmission method in the first embodiment of the present application
  • Fig. 6 is a schematic diagram of a low-resistance reverse amplifier circuit according to the first embodiment of the present application.
  • FIG. 7 is a diagram of input and output waveforms of the low-impedance reverse amplifier circuit in the first embodiment of the present application.
  • Fig. 8 is a schematic diagram of a high-impedance non-inverting amplifier circuit according to the first embodiment of the present application.
  • FIG. 9 is a diagram of input and output waveforms of the high-impedance non-inverting amplifier circuit in the first embodiment of the present application.
  • FIG. 10 is a schematic diagram of the same direction hysteresis comparison circuit in the first embodiment of the present application.
  • Fig. 11 is a diagram of input and output waveforms of the same-directional hysteresis comparison circuit in the first embodiment of the present application;
  • Fig. 12 is a schematic diagram of a reverse hysteresis comparison circuit in the first embodiment of the present application.
  • FIG. 13 is a diagram of input and output waveforms of the reverse hysteresis comparator circuit in the first embodiment of the present application.
  • FIG. 14 is a schematic diagram of a combination of a low resistance inverting amplifier circuit and a reverse hysteresis comparison circuit in the first embodiment of the present application;
  • 15 is a circuit diagram of the input and output waveforms of the combination of the low-resistance inverting amplifier circuit and the inverted hysteresis comparator circuit in the first embodiment of the present application;
  • 16 is a schematic diagram of a combination of a low-resistance inverting amplifier circuit and a same direction hysteresis comparison circuit in the first embodiment of the present application;
  • FIG. 17 is a circuit diagram of input and output waveforms of a combination of a low-resistance inverting amplifier circuit and a same-directional hysteresis comparator circuit in the first embodiment of the present application;
  • FIG. 18 is a flowchart of the implementation process of step 202 in the first embodiment of the present application.
  • step 603 is a flowchart of the implementation process of step 603 in the second embodiment of the present application.
  • FIG. 20 is a schematic diagram showing the bitwise exclusive-OR accumulation of the original coding signal signal1 and the autocorrelation demodulation signal signal2 in the second embodiment of the present application to identify effective signal codes;
  • FIG. 21 is a flowchart of a signal transmission method according to the third embodiment of the present application.
  • 22 is a schematic diagram of the structure of the active pen in the fourth embodiment of the present application.
  • FIG. 23 is a schematic structural diagram of a touch screen according to a fifth embodiment of the present application.
  • 24 is a schematic diagram of a signal transmission system in a sixth embodiment according to the present application.
  • Fig. 25 is a schematic diagram of a chip in a seventh embodiment according to the present application.
  • the first embodiment of the present application relates to a signal transmission method, which can be used for mobile phones, tablets, computers and other applications with active pen and touch functions.
  • Figure 1 shows the application scenario of the signal transmission method in this embodiment.
  • the touch screen 104 can form a coupling capacitor 103 with the electrode 102 of the active pen 101, and the touch screen 104 can send DSSS with TX ⁇ RX sensor Signal, the active pen 101 uses the coupling capacitor 103 to receive the DSSS signal sent by the touch screen 104, and then analyzes the DSSS signal to realize the information interaction between the active pen 101 and the touch screen 104.
  • the flow chart of the signal transmission method of this embodiment may be as shown in FIG. 2 and includes:
  • Step 201 Receive the DSSS signal sent by the touch screen through the coupling capacitor formed between the active pen and the touch screen.
  • the touch screen can perform spread-spectrum encoding on the signal to be transmitted to generate a DSSS signal.
  • the touch screen can use TX ⁇ RX sensor to send the DSSS signal, and the active pen uses the coupling capacitor to receive the DSSS signal sent by the touch screen.
  • the coupling capacitor formed between the active pen and the touch screen in this embodiment may be the coupling capacitor 103 shown in FIG. 1.
  • the active pen 101 includes a main electrode 302 and a secondary electrode 303, and the coupling formed between the active pen and the touch screen
  • the capacitance can be a coupling capacitor 305 formed between the main electrode 302 and the touch screen 104, or a coupling capacitor 306 formed between the secondary electrode 303 and the touch screen 104.
  • the active pen 101 can receive the DSSS signal through the coupling capacitor 305 and can also receive the DSSS signal through the coupling capacitor 306.
  • the spread-spectrum coding of the signal to be transmitted in this embodiment can adopt the DSSS spread-spectrum coding form of "0" and "1" in the universal serial interface USI protocol, as shown in Figure 4, "0” is represented by 31bit coding 0x58F9A42B , "1” is represented by 31bit code 0x27065BD4, and the duration of each bit is 1us.
  • the DSSS signal encoding in the USI protocol is only taken as an example, but it is not limited to this spread spectrum encoding in practical applications.
  • Step 202 Analyze the received DSSS signal to obtain the signal to be transmitted.
  • Fig. 5 the DSSS signal received by the active pen through the coupling capacitor 501 is input to the CCDM (Comparator Counter DSSS Mixer) analysis system 502 in the active pen, and the CCDM analysis system 502 performs processing on the received DSSS signal Analyze, get the signal to be transmitted.
  • CCDM Compparator Counter DSSS Mixer
  • the CCDM analysis system 502 includes: a pre-amplification circuit 503, a hysteresis comparison circuit 504, and a digital demodulation circuit 505.
  • the pre-amplification circuit 503 pre-amplifies the received DSSS signal
  • the pre-amplified DSSS signal is input to the hysteresis comparison circuit 504
  • the pre-amplified DSSS signal is restored through the hysteresis comparison circuit 504
  • the restored DSSS signal is input to the digital solution
  • the modulation circuit 505 demodulates the restored DSSS signal through the digital demodulation circuit 505, and analyzes the specific coding information of the DSSS signal, which is the signal to be transmitted.
  • the pre-amplification circuit 503 may be an AFE (Analog front end) circuit, and the AFE circuit may be an inverting amplifying circuit, such as a low-impedance inverting amplifying circuit as shown in FIG. 6.
  • the DSSS signal is used as the input signal of the inverting input end of the operational amplifier OPA in the low resistance inverting amplifier circuit.
  • the input and output waveforms of the low-impedance inverting amplifier circuit can be shown in Figure 7.
  • the input is the DSSS encoded signal in the USI protocol. Taking code 0 as an example, the output is the reverse amplified signal V1, and VP is the positive output of the amplified signal. Amplitude, VN is the negative output amplitude of the amplified signal, VCMI (Voltage Common Mode Input) is the common mode input voltage, and the output amplitude can be controlled by the parameters of the resistor and capacitor in the configuration diagram.
  • the AFE circuit can be a non-inverting amplifying circuit, for example, as shown in FIG. 8 for a high-impedance non-inverting amplifying circuit, the DSSS signal is used as the input signal of the non-inverting input terminal of the operational amplifier OPA in the high-impedance non-inverting amplifying circuit.
  • the input and output waveforms of the high-impedance non-inverting amplifying circuit can be shown in Figure 9.
  • the input is the DSSS coded signal in the USI protocol. Taking code 1 as an example, the output is the same-directional amplifying signal V1, through the resistor and capacitor in the configuration diagram.
  • the parameter of can control its output amplitude.
  • the hysteresis comparison circuit 504 may be a same direction hysteresis comparison circuit or a reverse hysteresis comparison circuit. The following two examples are used to specifically describe the hysteresis comparison circuit 504:
  • the hysteresis comparison circuit 504 can be the same direction hysteresis comparison circuit in FIG. 10, and the same direction hysteresis comparison circuit can restore the pre-amplified waveform to the original DSSS signal.
  • V1 is the output of the AFE circuit
  • V1 is the input of the same direction as the comparator
  • V2 is the output of the hysteresis comparator circuit.
  • the hysteresis comparison circuit 504 can be the reverse hysteresis comparison circuit in FIG. 12, and the reverse hysteresis comparison circuit can restore the pre-amplified waveform to the reverse signal of the original DSSS signal.
  • V1 is the output of the AFE circuit
  • V1 is the inverting input of the comparator.
  • the pre-amplification circuit 503 and the hysteresis comparison circuit 504 can be combined in a variety of ways.
  • the combination can be: a high-impedance non-inverting amplifying circuit and a non-inverting hysteresis comparison circuit, a high-impedance non-inverting amplifying circuit and a reverse hysteresis comparison circuit Combination, the low resistance inverting amplifier circuit is combined with the same direction hysteresis comparison circuit, and the low resistance inverting amplifier circuit is combined with the reverse hysteresis comparison circuit. Either combination method can restore the original DSSS signal to the same direction signal or reverse signal.
  • the digital demodulation circuit 505 analyzes that when the restored signal is an inverted signal, the digital demodulation circuit 505 adds an inverted function to know the original signal.
  • the combination of the pre-amplification circuit 503 and the hysteresis comparison circuit 504 is: a combination of a low-impedance inverting amplifying circuit 5031 and a reverse hysteresis comparison circuit 5041, as shown in FIG. 14, where the active pen and the touch screen coupling capacitance formed low-resistance input received DSSS signal inverting amplifying circuit 5031 inverting input terminal of the operational amplifier OPA, the output signal of the operational amplifier OPA AFE _ OUT inverted input terminal of the hysteresis comparator inverting input circuit 5041.
  • the waveform diagram of the reverse input signal DSSS signal, output signal V1, and output signal V2 of the reverse hysteresis comparison circuit 5041 of the low-resistance inverting amplifier circuit 5031 is shown in FIG. 15, where the DSSS signal is based on the DSSS of the USI protocol. Coding is taken as an example.
  • the DSSS coding in FIG. 15 takes the 31-bit code 0x58F9A42B of the original coded signal "0" as an example, but it is not limited to this in practical applications. It can be seen from FIG. 15 that the combination of the low resistance inverting amplifier circuit 5031 and the reverse hysteresis comparison circuit 5041 can restore the original DSSS signal to the same direction signal after pre-amplification.
  • the combination of the pre-amplification circuit 503 and the hysteresis comparison circuit 504 is: the low-impedance inverting amplifier circuit 5032 is combined with the non-inverting hysteresis comparison circuit 5042.
  • the DSSS signal is input with low-impedance inverting
  • the inverting input terminal of the operational amplifier OPA in the amplifying circuit 5032, and the output signal V1 of the operational amplifier OPA is input to the same direction input terminal of the same direction hysteresis comparison circuit 5042.
  • the inverted input signal DSSS signal, the output signal V1, and the output signal V2 of the same direction hysteresis comparison circuit 5042 of the low-resistance inverting amplifier circuit 5032 are shown in FIG. 17, where the DSSS signal adopts the DSSS of the USI protocol. Coding is taken as an example.
  • the DSSS coding in Figure 17 takes the 31b it code 0x58F9A42B of the original coded signal "0" as an example, but it is not limited to this in practical applications. It can be seen from FIG. 17 that the combination of the low resistance inverting amplifier circuit 5032 and the same direction hysteresis comparison circuit 5042 can restore the original DSSS signal to an inverted signal after pre-amplification.
  • the signal V2 output by the hysteresis comparison circuit 504 is input to the digital demodulation circuit 505, and the digital demodulation circuit 505 demodulates the signal to be transmitted, so as to realize the information interaction between the touch screen and the active pen.
  • step 202 can refer to FIG. 18, which specifically includes:
  • Step 601 Pre-amplify the received DSSS signal through the pre-amplification circuit.
  • Step 602 Input the pre-amplified DSSS signal into the hysteresis comparison circuit, and restore the pre-amplified DSSS signal through the hysteresis comparison circuit.
  • Step 603 Input the restored DSSS signal into the digital demodulation circuit, demodulate the restored DSSS signal through the digital demodulation circuit, and output the signal to be transmitted.
  • this embodiment receives the DSSS signal sent by the touch screen through the coupling capacitor formed between the active pen and the touch screen.
  • the DSSS signal is a signal to be transmitted after spread spectrum encoding;
  • the DSSS signal is analyzed to obtain the signal to be transmitted.
  • the DSSS signal is received through capacitive coupling, which can be well adapted to the transmission of DSSS signals in the touch control system.
  • only a first-level pre-amplification circuit, a first-level hysteresis comparison circuit, and a first-level digital demodulation circuit are needed to analyze the received DSSS signal.
  • the circuit structure is simple, the required hardware resources are less, and the Low power consumption, very suitable for use in the interactive system of active pen and touch screen which has strict requirements on circuit size and power consumption.
  • the second embodiment of the present application relates to a signal transmission method.
  • This embodiment mainly describes the implementation process of step 603 in the first embodiment in detail, that is, how to deal with the restored DSSS signal through the digital demodulation circuit.
  • the demodulation is described in detail.
  • the digital demodulation circuit can use the corresponding algorithm to realize its corresponding function.
  • the flowchart of the specific algorithm can be referred to as shown in Figure 19, including:
  • Step 701 Sample the restored DSSS signal through a digital demodulation circuit to obtain an original coded signal.
  • the USI active pen touch protocol is taken as an example.
  • the restored DSSS signal output by the hysteresis comparison circuit can be sampled at a sampling frequency of N Mhz to obtain the original coding signal signal1
  • the original coding signal signal1 includes the first type of signal, the second type of signal and the third type of signal.
  • the first type of signal is the spread code 0x58F9A428 corresponding to the "0" in the signal to be transmitted
  • the second type of signal is the "0" in the signal to be transmitted. 1" corresponds to the spread spectrum code 0x27065BD4, and the third type of signal is useless.
  • Step 702 Perform a bitwise exclusive OR between the original coding signal and the preset autocorrelation demodulation signal.
  • the autocorrelation demodulation signal can be shifted back by 1 bit as a whole; where B is the number of bits of the autocorrelation demodulation signal, that is, the autocorrelation demodulation signal signal2 is Move as a whole on the time axis, so that the collected original coded signal can be XORed with the corresponding autocorrelation demodulated signal.
  • the autocorrelation demodulation signal can be the first type signal or the second type signal. In this embodiment, the autocorrelation demodulation signal takes the first type signal as an example. As shown in FIG. 20, the waveform diagram of the autocorrelation demodulation signal signal2 is Waveform of "Code 0".
  • the autocorrelation demodulation signal signal2 It is a 31*N wavetable storage. As each sampling point is taken in, the autocorrelation demodulation signal signal2 is shifted bitwise, and the above-mentioned exclusive OR of the original coded signal signal1 and the autocorrelation demodulation signal signal2 is repeated.
  • Step 703 Accumulate the result of the bitwise XOR to obtain the accumulation result.
  • the B-bit original coding signal and the B-bit auto-correlation demodulated signal can be accumulated by bit-wise XOR to obtain the accumulated result.
  • the result is close to 31*N; when a segment of coded "0" signal in signal1 and autocorrelation signal
  • the demodulation signal signal2 is synchronously XORed and accumulated, the result obtained is close to 0; when the unnecessary signal in the original coding signal signal1 is XORed and accumulated with the autocorrelation demodulation signal signal2, the result obtained is close to 31*N/2.
  • Step 704 Demodulate the restored DSSS signal according to the accumulation result.
  • the restored DSSS signal can be demodulated according to the comparison result of the accumulated result and the preset threshold respectively.
  • the preset threshold may include a first preset threshold and a second preset threshold, and the second preset threshold is greater than the first preset threshold.
  • the first preset threshold Threshold_L may be a natural number greater than or equal to 0 and less than or equal to B*N/2, that is, 0 ⁇ Threshold_L ⁇ B*N/2.
  • the second preset threshold Threshold_H can be a natural number greater than B*N/2 and less than or equal to B*N, that is, B*N/2 ⁇ Threshold_H ⁇ B*N, where B is the number of bits of the autocorrelation demodulation signal Since the autocorrelation demodulation signal in this embodiment takes 31-bit data encoding as an example, B in this embodiment is 31; N is the sampling frequency at which the digital demodulation circuit samples the restored DSSS signal. In other words, in this embodiment, 0 ⁇ Threshold_L ⁇ 31*N/2, and 31*N/2 ⁇ Threshold_H ⁇ 31*N.
  • the detected accumulation result is less than or equal to Threshold_L, it is identified that the B-bit original coding signal is the first type of signal; if the detected accumulation result is greater than or equal to Threshold_H, it is identified that the B-bit original coding signal is The second type of signal; if the detected accumulation result is greater than Threshold_L and less than Threshold_H, it is identified that the B-bit original coding signal is a useless signal.
  • Threshold_L it is identified that the B-bit original coding signal is the first type of signal
  • Threshold_H it is identified that the B-bit original coding signal is The second type of signal
  • the detected accumulation result is greater than Threshold_L and less than Threshold_H, it is identified that the B-bit original coding signal is a useless signal.
  • Threshold_H If the accumulation result is greater than Threshold_H, code 1 can be identified, if it is less than Threshold_L, code 0 can be identified, and if it is less than Threshold_H and greater than Threshold_L, it can be identified as a useless signal. It can be seen from Fig. 20 that the samples obtained at T0, T1, T2, Tm, and Tn are all useless signals. The code is sampled at Tm+1, and code 0 is sampled at Tn+1.
  • the start time of the collected B-bit original coding signal can also be used as the start time of the identified first type of signal; If the accumulated result is greater than or equal to the second preset threshold, the start time of the collected B-bit original coding signal can also be used as the identified start time of the second type of signal.
  • the start time of the collected B-bit original coding signal can also be used as the identified start time of the second type of signal.
  • code 1 can be identified, and it can be learned that the starting time of this code "1" is the starting time of collecting the original coding signal, that is, in the figure Identified "starting time Tm+1 of effective signal code 1"; if it is less than Threshold_L, code 0 can be identified, and it can be learned that the starting time of this code "0" is the beginning of the collection of the original coding signal Time, that is, the starting time Tn+1 of the "effective signal code 0" identified in the figure.
  • the digital demodulation circuit can analyze the DSSS signal restored by the hysteresis comparison circuit, and can synchronize the DSSS signal to detect its start time, and realize the connection between the touch screen and the active pen. Timing synchronization to better carry out the information interaction between the touch screen and the active pen.
  • the third embodiment of the present application relates to a signal transmission method, which is applied to a touch screen.
  • the specific flowchart is shown in FIG. 21 and includes:
  • Step 801 Perform spread spectrum coding on the signal to be transmitted to generate a DSSS signal.
  • step 802 the DSSS signal is sent to the active pen through the coupling capacitor formed between the active pen and the touch screen, so that the active pen can analyze the received DSSS signal to obtain the signal to be transmitted.
  • the signal transmission methods of this embodiment are applied to a touch screen
  • the signal transmission methods of the first and second embodiments are applied to an active pen, and this embodiment can be implemented in cooperation with the first and second embodiments.
  • the related technical details mentioned in the first and second embodiments are still valid in this embodiment, and in order to reduce repetition, they will not be repeated here.
  • the related technical details mentioned in this embodiment can also be applied to the first and second embodiments.
  • the DSSS signal is transmitted through the coupling capacitor formed between the active pen and the touch screen, which can be well adapted to the transmission of the DSSS signal in the touch system.
  • only a first-level pre-amplification circuit, a first-level hysteresis comparison circuit, and a first-level digital demodulation circuit are needed to analyze the received DSSS signal.
  • the circuit structure is simple, the required hardware resources are less, and the Low power consumption, very suitable for use in the interactive system of active pen and touch screen which has strict requirements on circuit size and power consumption.
  • the fourth embodiment of the present application relates to an active pen. As shown in FIG. 22, it includes: at least one processor 901; and a memory 902 communicatively connected with the at least one processor 901; wherein the memory 902 stores at least one The instructions executed by the processor 901 are executed by the at least one processor 901, so that the at least one processor 901 can execute the foregoing signal transmission method applied to the active pen.
  • the memory 902 and the processor 902 are connected in a bus manner.
  • the bus may include any number of interconnected buses and bridges, and the bus connects one or more processors and various circuits of the memory 902 together.
  • the bus can also connect various other circuits such as peripheral devices, voltage regulators, power management circuits, etc., which are all well-known in the art, and therefore, no further description will be given herein.
  • the bus interface provides an interface between the bus and the transceiver.
  • the transceiver may be one element or multiple elements, such as multiple receivers and transmitters, providing a unit for communicating with various other devices on the transmission medium.
  • the data processed by the processor 902 is transmitted on the wireless medium through the antenna, and further, the antenna also receives the data and transmits the data to the processor 902.
  • the processor 902 is responsible for managing the bus and general processing, and can also provide various functions, including timing, peripheral interfaces, voltage regulation, power management, and other control functions.
  • the memory 902 may be used to store data used by the processor 902 when performing operations.
  • the fifth embodiment of the present application relates to a touch screen, as shown in FIG. 23, including: at least one processor 1001; and a memory 1002 communicatively connected with at least one processor 1001; wherein, the memory 1002 stores at least An instruction executed by one processor 1001 is executed by at least one processor 1001, so that the at least one processor 1001 can execute the above-mentioned signal transmission method applied to a touch screen.
  • the memory 1002 and the processor 1002 are connected in a bus manner.
  • the bus may include any number of interconnected buses and bridges.
  • the bus connects one or more processors and various circuits of the memory 1002 together.
  • the bus can also connect various other circuits such as peripheral devices, voltage regulators, power management circuits, etc., which are all well-known in the art, and therefore, no further description will be given herein.
  • the bus interface provides an interface between the bus and the transceiver.
  • the transceiver may be one element or multiple elements, such as multiple receivers and transmitters, providing a unit for communicating with various other devices on the transmission medium.
  • the data processed by the processor 1002 is transmitted on the wireless medium through the antenna, and further, the antenna also receives the data and transmits the data to the processor 1002.
  • the processor 1002 is responsible for managing the bus and general processing, and can also provide various functions, including timing, peripheral interfaces, voltage regulation, power management, and other control functions.
  • the memory 1002 may be used to store data used by the processor 1002 when performing operations.
  • the sixth embodiment of the present application relates to a signal transmission system, as shown in FIG. 24, including: a touch screen 1101 and an active pen 1102.
  • the touch screen 1101 is used to perform spread spectrum coding on the signal to be transmitted to generate a DSSS signal; the touch screen 1101 is also used to send the DSSS signal to the active pen 1102 through the coupling capacitor 1103 formed with the active pen 1102; the active pen 1102, Used to analyze the received DSSS signal to obtain the signal to be transmitted.
  • this embodiment is a system example corresponding to the first, second and third embodiments, and this embodiment can be implemented in cooperation with the first, second and third embodiments.
  • the related technical details mentioned in the first, second, and third embodiments are still valid in this embodiment, and in order to reduce repetition, they will not be repeated here.
  • the related technical details mentioned in this embodiment can also be applied to the first, second and third embodiments.
  • the DSSS signal is transmitted through the coupling capacitor formed between the active pen and the touch screen, which can be well adapted to the transmission of the DSSS signal in the touch system.
  • the active pen only needs a first-level pre-amplification circuit, a first-level hysteresis comparison circuit, and a first-level digital demodulation circuit to analyze the received DSSS signal.
  • the circuit structure is simple and requires less hardware resources. , Low power consumption, very suitable for use in the interactive system of active pen and touch screen that has strict requirements on circuit size and power consumption.
  • the seventh embodiment of the present application relates to a chip, as shown in FIG. 25, including: a pre-amplification circuit 1201, configured to send to the touch screen received through the coupling capacitor formed between the active pen and the touch screen
  • the DSSS signal is pre-amplified, and the pre-amplified DSSS signal is output to the hysteresis comparison circuit 1202; the hysteresis comparison circuit 1202 is used to restore the pre-amplified DSSS signal to restore the restored DSSS signal.
  • the DSSS signal is output to the digital demodulation circuit 1203; the digital demodulation circuit 1203 is used to demodulate the restored DSSS signal.
  • the pre-amplification circuit 1201 can be an inverting amplifying circuit or a non-inverting amplifying circuit
  • the hysteresis comparison circuit can be: a non-inverting hysteresis comparison circuit or a reverse hysteresis comparison circuit.
  • the inverting amplifier circuit may be a low resistance inverting amplifier circuit as shown in FIG. 6.
  • the low-resistance reverse amplifier circuit includes: a first operational amplifier, a first feedback resistor RF1 and a first feedback capacitor CF1; wherein the non-inverting input terminal of the first operational amplifier is connected to the input voltage VCMI, and the reverse input terminal is connected to the DSSS signal.
  • the first feedback resistor RF1 is connected across the inverting input terminal and the output terminal of the first operational amplifier, and the first feedback capacitor CF1 is connected in parallel with the first feedback resistor RF1.
  • the first terminal of the first feedback resistor RF1 is connected to the inverting input terminal of the first operational amplifier, and the second terminal is connected to the output terminal of the first operational amplifier.
  • the first end of the first feedback capacitor CF1 is connected to the first end of the first feedback resistor RF1, and the second end is connected to the second end of the first feedback resistor RF1.
  • the non-inverting amplifying circuit may be a high-impedance co-directional amplifying circuit as shown in FIG. 8.
  • the high-impedance non-directional amplifier circuit includes: a second operational amplifier, a second feedback resistor RF2, a second feedback capacitor CF2, a first resistor R1, and a second resistor R2; wherein the non-inverting input terminal of the second operational amplifier is connected to the DSSS signal, and The reverse input terminal is connected to the second terminal of the second resistor R2, and the first terminal of the second resistor R2 is connected to the first input voltage VCMI1.
  • the second feedback resistor RF2 is connected across the inverting input terminal and the output terminal of the second operational amplifier, and the second feedback capacitor CF2 is connected in parallel with the second feedback resistor RF2. That is, the first terminal of the second feedback resistor RF2 is connected to the inverting input terminal of the second operational amplifier, and the second terminal is connected to the output terminal of the second operational amplifier.
  • the first end of the second feedback capacitor CF2 is connected to the first end of the second feedback resistor RF2, and the second end is connected to the second end of the second feedback resistor RF2.
  • the first end of the first resistor R1 is connected to the non-inverting input end of the second operational amplifier, and the second end is connected to the second input voltage VCMI2, where VCMI1 and VCMI2 can be the same.
  • the circuit diagram of the same direction hysteresis comparison circuit may be as shown in FIG. 10, including: a first comparator, a third resistor R3, a fourth resistor R4, and a fifth resistor R5; the first end of the third resistor R3 and The output terminal V1 of the pre-amplification circuit is connected, and the second terminal is connected to the non-inverting input terminal of the first comparator.
  • the fourth resistor R4 is connected across the non-inverting input terminal and the output terminal of the first comparator. That is, the first terminal of the fourth resistor R4 is connected to the second terminal of the third resistor R3, and the second terminal is connected to the output terminal V2 of the first comparator.
  • the first terminal of the fifth resistor R5 is connected to the input voltage VCMI, and the second terminal is connected to the inverting input terminal of the first comparator.
  • the circuit diagram of the reverse hysteresis comparison circuit may be as shown in FIG. 11, including: a second comparator, a sixth resistor R6, a seventh resistor R7, and an eighth resistor R8; where the first resistor of the sixth resistor R6 The terminal is connected with the input voltage VCMI, and the second terminal is connected with the positive input terminal of the second comparator.
  • the seventh resistor R7 is connected across the same direction input terminal and the output terminal of the second comparator. That is, the first terminal of the seventh resistor R7 is connected to the second terminal of the sixth resistor R6, and the second terminal is connected to the output terminal V2 of the second comparator.
  • the first terminal of the eighth resistor R8 is connected to the output terminal V1 of the preamplifier circuit, and the second terminal is connected to the inverting input terminal of the second comparator.
  • the embodiment of the present application transmits the DSSS signal through the coupling capacitor formed between the active pen and the touch screen, which is well suited for the transmission of the DSSS signal in the touch system.
  • a first-level pre-amplification circuit a first-level hysteresis comparison circuit, and a first-level digital demodulation circuit are needed to analyze the received DSSS signal.
  • the circuit structure is simple, the required hardware resources are less, and the Low power consumption, very suitable for use in the interactive system of active pen and touch screen which has strict requirements on circuit size and power consumption.
  • the eighth embodiment of the present application relates to an active pen, including the chip in the seventh embodiment.
  • the ninth embodiment of the present application relates to a computer-readable storage medium storing a computer program.
  • the computer program is executed by the processor, the foregoing signal transmission method embodiment is realized.
  • the program is stored in a storage medium and includes several instructions to enable a device ( It may be a single-chip microcomputer, a chip, etc.) or a processor (processor) to execute all or part of the steps of the methods in the embodiments of the present application.
  • the aforementioned storage media include: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), magnetic disk or optical disk and other media that can store program code .

Abstract

一种信号传输方法、系统、主动笔、触控屏和可读存储介质。信号传输方法包括：通过主动笔与触控屏之间形成的耦合电容接收触控屏发送的DSSS信号(201)；其中，所述DSSS信号为经过扩频编码的待传输信号；对接收的DSSS信号进行解析，得到待传输信号(202)，所需硬件资源少，功耗低，能够很好的适用于主动笔触控系统中。

Description

信号传输方法、系统、主动笔、触控屏和可读存储介质 技术领域
本申请涉及触控技术领域，特别涉及一种信号传输方法、系统、主动笔、触控屏和可读存储介质。
背景技术
目前，在新型的主动笔触控系统中，触控屏可发射DSSS信号与笔端通信，从而实现屏端与笔端同步，并发送命令等操作。笔端如何实现正确的接收屏端发送的DSSS信号成为关键。
现有技术中DSSS信号传输通常应用在射频环境中，即通过高频天线收发DSSS信号。然而，发明人发现，由于屏端传感器自身存在阻抗等条件限制，使得DSSS信号频谱扩展受限，因此通过高频天线收发DSSS信号的方式并不适合应用在对结构、尺寸、功耗等有严格要求的主动笔触控系统中。
发明内容
本申请部分实施例的目的在于提供一种信号传输方法、系统、主动笔、触控屏和可读存储介质，触控屏与主动笔通过电容耦合的方式传递DSSS信号，能够很好的适用于对结构、尺寸、功耗等有严格要求的主动笔触控系统中。
本申请实施例提供了一种信号传输方法，应用于主动笔，包括：通过所 述主动笔与触控屏之间形成的耦合电容接收所述触控屏发送的DSSS信号；其中，所述DSSS信号为经过扩频编码的待传输信号；对接收的所述DSSS信号进行解析，得到所述待传输信号。
本申请实施例提供了一种信号传输方法，应用于触控屏，包括：对待传输信号进行扩频编码生成DSSS信号；通过主动笔与所述触控屏之间形成的耦合电容将所述DSSS信号发送至所述主动笔，以供所述主动笔对接收的所述DSSS信号进行解析，得到所述待传输信号。
本申请实施例还提供了一种主动笔，包括：至少一个处理器；以及，与所述至少一个处理器通信连接的存储器；其中，所述存储器存储有可被所述至少一个处理器执行的指令，所述指令被所述至少一个处理器执行，以使所述至少一个处理器能够执行如上所述的应用于主动笔的信号传输方法。
本申请实施例还提供了一种触控屏，包括：至少一个处理器；以及，与所述至少一个处理器通信连接的存储器；其中，所述存储器存储有可被所述至少一个处理器执行的指令，所述指令被所述至少一个处理器执行，以使所述至少一个处理器能够执行如上所述的应用于触控屏的信号传输方法。
本申请实施例还提供了一种信号传输系统，包括：触控屏和主动笔；所述触控屏，用于对待传输信号进行扩频编码生成DSSS信号；所述触控屏，还用于通过与所述主动笔之间形成的耦合电容将所述DSSS信号发送至所述主动笔；所述主动笔，用于对接收的所述DSSS信号进行解析，得到所述待传输信号。
本申请实施例还提供了一种计算机可读存储介质，存储有计算机程序，计算机程序被处理器执行时实现上述的信号传输方法。
本申请实施例还提供了一种芯片，包括：预放大电路，用于对通过所述 主动笔与触控屏之间形成的耦合电容接收的所述触控屏发送的DSSS信号进行预放大，将预放大后的所述DSSS信号输出至迟滞比较电路；所述迟滞比较电路，用于对所述预放大后的所述DSSS信号进行还原，将还原后的所述DSSS信号输出至数字解调电路；所述数字解调电路，用于对还原后的DSSS信号进行解调。
本申请实施例还提供了一种主动笔，包括上述的芯片。
本申请实施例相对于现有技术而言，通过主动笔与触控屏之间形成的耦合电容接收触控屏发送的DSSS信号，DSSS信号为经过扩频编码的待传输信号；主动笔对接收的所述DSSS信号进行解析，得到待传输信号。本申请实施例，通过主动笔与触控屏之间形成的耦合电容传输DSSS信号，能够很好的适用在触控系统中。发明人发现，在触控系统中，由于屏端传感器自身存在阻抗等条件限制，使其DSSS信号频谱扩展受限，即在触控系统中，因为受屏体寄生参数的影响，DSSS信号频率不能扩展太大。在通用主动笔协议USI中，DSSS频谱最高只到1MHz，达不到射频水平且主动笔对结构、尺寸与功耗等有较为严格的要求，即主动笔在实际应用中尺寸较小，若通过射频天线传输DSSS信号，会限制主动笔内射频天线的尺寸，从而更达不到射频水平。因此，利用传统的射频方式传输DSSS信号并不适用在触控系统中。本申请实施例中，通过主动笔与触控屏之间形成的耦合电容传输DSSS信号，可以很好的适用于触控系统中DSSS信号的传输，同时还可以满足主动笔对结构、尺寸与功耗的严格要求。
例如，对接收的所述DSSS信号进行解析，得到所述待传输信号，具体包括：通过预放大电路对接收的所述DSSS信号进行预放大；将预放大后的所述DSSS信号输入迟滞比较电路，通过所述迟滞比较电路对所述预放大后的所述DSSS信号进行还原；将还原后的所述DSSS信号输入数字解调电路，通过所述 数字解调电路对所述还原后的所述DSSS信号进行解调，输出所述待传输信号，依次通过预放大电路、迟滞比较电路和数字解调电路的处理有利于准确的对接收的DSSS信号进行解调，从而输出待传输信号，以实现触控屏与主动笔之间进行准确的信号传输。而且，本实施例中，只需要一级预放大电路、一级迟滞比较电路、一级数字解调电路就可以实现对接收的DSSS信号的解析，电路结构简洁，所需硬件资源较少，功耗较低，非常适合应用于对电路尺寸、功耗等有严格要求的主动笔与触控屏的交互系统中。
例如，所述通过所述数字解调电路对所述还原后的所述DSSS信号进行解调，具体包括：通过所述数字解调电路对所述还原后的所述DSSS信号进行采样得到原始打码信号；将所述原始打码信号与预设的自相关解调信号按位异或；将所述按位异或的结果进行累加，得到累加结果；根据所述累加结果，对所述还原后的所述DSSS信号进行解调。
例如，将所述原始打码信号与预设的自相关解调信号按位异或，具体包括：每采集到B位原始打码信号后，将所述自相关解调信号整体后移1位；其中，所述B为所述自相关解调信号的位数；将所述B位原始打码信号与B位所述自相关解调信号按位异或；所述将所述按位异或的结果进行累加，得到累加结果，具体为：将所述B位原始打码信号与B位所述自相关解调信号按位异或的结果进行累加，得到累加结果；根据所述累加结果，对所述还原后的所述DSSS信号进行解调，具体为：根据所述累加结果与预设门限的比较结果，对所述还原后的所述DSSS信号进行解调，提供了一种具体的解调方式，有利于有效的对接收的DSSS信号的解调。
例如，原始打码信号包括第一类信号、第二类信号和第三类信号，所述 第一类信号为所述待传输信号中的“0”所对应的扩频编码，所述第二类信号为所述待传输信号中的“1”所对应的扩频编码，所述第三类信号为无用信号；若所述自相关解调信号为第一类信号，则所述根据所述累加结果与预设门限的比较结果，对所述还原后的所述DSSS信号进行解调，具体包括：若检测到累加结果小于或等于第一预设阈值，则识别出所述B位原始打码信号为第一类信号；若检测到所述累加结果大于或等于第二预设阈值，则识别出所述B位原始打码信号为第二类信号；其中，所述第二预设阈值大于所述第一预设阈值；若检测到所述累加结果大于所述第一预设阈值且小于所述第二预设阈值，则识别出所述B位原始打码信号为无用信号。通过将每一段的累加结果与第一预设阈值和第二预设阈值进行比较，有利于准确的对原始打码信号进行解析，进而实现对完成的DSSS信号进行解解析。
例如，若检测到累加结果小于或等于第一预设阈值，则还包括：将采集到所述B位原始打码信号的起始时刻作为识别出的所述第一类信号的起始时刻；若检测到的累加结果大于或等于第二预设阈值，则还包括：将采集到所述B位原始打码信号的起始时刻作为识别出的所述第二类信号的起始时刻，有利于得到解析出的信号的起始时刻，实现屏端与笔端的时序同步。
例如，所述第一预设阈值大于或等于0，且小于或等于B*N/2；所述第二预设阈值大于所述B*N/2，且小于或等于B*N；其中，所述B为所述自相关解调信号的位数；所述N为所述数字解调电路对所述还原后的所述DSSS信号进行采样的采样频率。提供了一种第一预设阈值和第二预设阈值的设置方式，使得通过将每一段DSSS信号的累加结果与通过上述方式设置的第一预设阈值和第二预设阈值进行比较，能够更准确的对每一段DSSS信号进行解析，进而实现对完 成的DSSS信号进行解析。
例如，所述预放大电路具体为：同相放大电路或反相放大电路，提供了两种预放大电路的实现方式，使得本实施方式的实现方式灵活多样。
例如，所述迟滞比较电路具体为：同向迟滞比较电路或反向迟滞比较电路，提供了两种迟滞比较电路的实现方式，使得本实施方式的实现方式灵活多样。
例如，所述主动笔包括主电极和副电极，所述主动笔与触控屏之间形成的耦合电容具体为：所述主电极与所述触控屏之间形成的耦合电容，或者所述副电极与所述触控屏之间形成的耦合电容，使得主动笔与触控屏之间可以通过多种实现方式形成耦合电容。
附图说明
一个或多个实施例通过与之对应的附图中的图片进行示例性说明，这些示例性说明并不构成对实施例的限定，附图中具有相同参考数字标号的元件表示为类似的元件，除非有特别申明，附图中的图不构成比例限制。
图1是根据本申请第一实施例中的信号传输方法的应用场景的示意图；
图2是根据本申请第一实施例中的信号传输方法的流程图；
图3是根据本申请第一实施例中的主动笔与触控屏之间形成的耦合电容的示意图；
图4是根据本申请第一实施例中的“0”和“1”的DSSS扩频编码的波形图；
图5是根据本申请第一实施例中的信号传输方法的步骤202的实现框图；
图6是根据本申请第一实施例中的低阻反向放大电路的示意图；
图7是根据本申请第一实施例中的低阻反向放大电路的输入输出波形图；
图8是根据本申请第一实施例中的高阻同相放大电路的示意图；
图9是根据本申请第一实施例中的高阻同相放大电路的输入输出波形图；
图10是根据本申请第一实施例中的同向迟滞比较电路的示意图；
图11是根据本申请第一实施例中的同向迟滞比较电路的输入输出波形图；
图12是根据本申请第一实施例中的反向迟滞比较电路的示意图；
图13是根据本申请第一实施例中的反向迟滞比较电路的输入输出波形图；
图14是根据本申请第一实施例中的低阻反相放大电路与反向迟滞比较电路组合的示意图；
图15是根据本申请第一实施例中的低阻反相放大电路与反向迟滞比较电路组合的电路的输入输出波形图；
图16是根据本申请第一实施例中的低阻反相放大电路与同向迟滞比较电路组合的示意图；
图17是根据本申请第一实施例中的低阻反相放大电路与同向迟滞比较电路组合的电路的输入输出波形图；
图18是根据本申请第一实施例中的步骤202的实现过程的流程图；
图19是根据本申请第二实施例中的步骤603的实现过程的流程图；
图20是根据本申请第二实施例中的原始打码信号signal1与自相关解调信号signal2按位异或累加识别有效信号编码的示意图；
图21是根据本申请第三实施例中的信号传输方法的流程图；
图22是根据本申请第四实施例中的主动笔的结构示意图；
图23是根据本申请第五实施例中的触控屏的结构示意图；
图24是根据本申请第六实施例中的信号传输系统的示意图；
图25是根据本申请第七实施例中的芯片的示意图。
具体实施方式
为了使本申请的目的、技术方案及优点更加清楚明白，以下结合附图及实施例，对本申请部分实施例进行进一步详细说明。应当理解，此处所描述的具体实施例仅仅用以解释本申请，并不用于限定本申请。
本申请第一实施例涉及一种信号传输方法，可以用于带主动笔与触控功能的手机、平板、电脑等应用产品。如图1所示为本实施例中的信号传输方法的应用场景，图1中，触控屏104可以与主动笔101的电极102形成耦合电容103，触控屏104可用TX\RX sensor发送DSSS信号，主动笔101利用耦合电容103接收触控屏104发送的DSSS信号，然后对DSSS信号进行解析，实现主动笔101与触控屏104之间的信息交互。
本实施例的信号传输方法的流程图可以如图2所示，包括：
步骤201，通过主动笔与触控屏之间形成的耦合电容接收触控屏发送的DSSS信号。
具体的说，可以由触控屏对待传输信号进行扩频编码生成DSSS信号，触控屏可用TX\RX sensor发送DSSS信号，主动笔利用耦合电容接收触控屏发送的DSSS信号。本实施例中主动笔与触控屏之间形成的耦合电容可以如图1中所 示的耦合电容103。在实际应用中，主动笔与触控屏之间形成的耦合电容的示意图还可以如图3所示：主动笔101包括主电极302和副电极303，主动笔与触控屏之间形成的耦合电容可以为：主电极302与触控屏104之间形成的耦合电容305，也可以为副电极303与触控屏104之间形成的耦合电容306。主动笔101可以通过耦合电容305接收DSSS信号，也可以通过耦合电容306接收DSSS信号。
另外，本实施例中对待传输信号进行扩频编码可以采用通用串行接口USI协议中“0”和“1”的DSSS扩频编码形式，如图4所示，“0”采用31bit编码0x58F9A42B表示，“1”采用31bit编码0x27065BD4表示，每个bit的时长为1us。本实施例中只是以USI协议中的DSSS信号编码为例，但在实际应用中并不局限于此种扩频编码。
步骤202，对接收的DSSS信号进行解析，得到待传输信号。
具体的说，可参考图5，图5中主动笔通过耦合电容501接收的DSSS信号输入至主动笔中的CCDM(Comparator Counter DSSS Mixer)解析系统502，CCDM解析系统502对接收到的DSSS信号进行解析，得到待传输信号。
其中，CCDM解析系统502中包括：预放大电路503、迟滞比较电路504和数字解调电路505。预放大电路503对接收的DSSS信号进行预放大，预放大后的DSSS信号输入至迟滞比较电路504，通过迟滞比较电路504对预放大后的DSSS信号进行还原，将还原后的DSSS信号输入数字解调电路505，通过数字解调电路505对还原后的DSSS信号进行解调，解析出DSSS信号的具体编码信息，即为待传输信号。
在一个例子中，预放大电路503可以为AFE(Analog front end，模拟 前端)电路，AFE电路可以为反相放大电路，比如说如图6所示的低阻反相放大电路。DSSS信号作为低阻反相放大电路中运算放大器OPA的反向输入端的输入信号。低阻反相放大电路的输入输出波形图可以如图7所示，输入为USI协议中的DSSS编码信号，以编码0为例，输出为反向放大信号V1，VP为被放大信号的正输出幅度，VN为被放大信号的负输出幅度，VCMI(Voltage Common Mode Input)为共模输入电压，通过配置图中的电阻电容等器件的参数可控制其输出幅度。
在另一个例子中，AFE电路可以为同相放大电路，比如说，如图8所示的高阻同相放大电路，DSSS信号作为高阻正相放大电路中运算放大器OPA的同向输入端的输入信号。高阻同相放大电路的输入输出波形图可以如图9所示，输入为USI协议中的DSSS编码信号，以编码1为例，输出为同向放大信号V1，通过配置图中的电阻电容等器件的参数可控制其输出幅度。
进一步的，迟滞比较电路504可以为同向迟滞比较电路或反向迟滞比较电路，下面以两个例子对迟滞比较电路504进行具体说明：
在一个例子中，迟滞比较电路504可以为图10中的同向迟滞比较电路，同向迟滞比较电路可将预放大之后的波形还原为原始DSSS信号。其中，V1为AFE电路的输出，V1作为比较器comparator的同向端输入，V2为迟滞比较电路的输出。同向迟滞比较电路的输入输出波形图可以如图11所示，其中，VTH与VTL为两个转换电平，具体的，VTL＝VCMI-(VDD-VCMI)*R3/R4，VTH＝VCMI(1+R3/R4)，调整R1和R2大小，可以调整VTH与VTL。
在另一个例子中，迟滞比较电路504可以为图12中的反向迟滞比较电路，反向迟滞比较电路可将预放大之后的波形还原为原始DSSS信号的反向信号。其 中，V1为AFE电路的输出，V1作为比较器comparator的反向端输入。反向迟滞比较电路的输入输出波形图可以如图13所示，其中VTL＝VCMI*R7/(R7+R6)，VTH＝VCMI+(VDD-VCMI)*R7/R6。
在实际应用中，预放大电路503和迟滞比较电路504可以由多种组合方式，组合方式可以为：高阻同相放大电路与同向迟滞比较电路组合，高阻同相放大电路与反向迟滞比较电路组合，低阻反相放大电路与同向迟滞比较电路组合，低阻反相放大电路与反向迟滞比较电路组合。任意一种组合方式均可以将原始DSSS信号还原为同向信号或是反向信号，如原始信号其中几位编码为“01101”，所谓同相信号，还原出的编码依然为“01101”，所谓反相信号，还原出的反相编码为“10010”。不管是还原出同相信号还是反相信号，数字解调电路505解析，对于还原出的信号为反相信号时，数字解调电路505加一个反相功能即可知原始信号。
在一个例子中，预放大电路503和迟滞比较电路504的组合方式为：低阻反相放大电路5031与反向迟滞比较电路5041组合，可参考图14，其中通过主动笔与触控屏之间形成的耦合电容接收的DSSS信号输入低阻反相放大电路5031中的运算放大器OPA的反向输入端，运算放大器OPA的输出信号AFE _OUT输入反向迟滞比较电路5041的反向输入端。进一步的，低阻反相放大电路5031的反向输入信号DSSS信号、输出信号V1、反向迟滞比较电路5041的输出信号V2的波形图如图15所示，其中，DSSS信号以USI协议的DSSS编码为例，图15中的DSSS编码以原始编码信号“0”的31bit编码0x58F9A42B为例，但在实际应用中并不以此为限。由图15可以看出，通过低阻反相放大电路5031与反向迟滞比较电路5041的组合可以将原始的DSSS信号经过预放大后还原为同 向信号。
在另一个例子中，预放大电路503和迟滞比较电路504的组合方式为：低阻反相放大电路5032与同向迟滞比较电路5042组合，可参考图16，其中，DSSS信号输入低阻反相放大电路5032中的运算放大器OPA的反向输入端，运算放大器OPA的输出信号V1输入同向迟滞比较电路5042的同向输入端。进一步的，低阻反相放大电路5032的反向输入信号DSSS信号、输出信号V1、同向迟滞比较电路5042的输出信号V2的波形图如图17所示，其中，DSSS信号以USI协议的DSSS编码为例，图17中的DSSS编码以原始编码信号“0”的31b it编码0x58F9A42B为例，但在实际应用中并不以此为限。由图17可以看出，通过低阻反相放大电路5032与同向迟滞比较电路5042的组合可以将原始的DSSS信号经过预放大后还原为反向信号。
最后，将迟滞比较电路504输出的信号V2输入到数字解调电路505，由数字解调电路505进行解调得到待传输信号，实现触控屏与主动笔之间的信息交互。
为进一步方便理解，步骤202的实现过程可以参考图18，具体包括：
步骤601：通过预放大电路对接收的DSSS信号进行预放大。
步骤602：将预放大后的DSSS信号输入迟滞比较电路，通过迟滞比较电路对预放大后的DSSS信号进行还原。
步骤603：将还原后的DSSS信号输入数字解调电路，通过数字解调电路对还原后的DSSS信号进行解调，输出待传输信号。
上述步骤601到步骤603在上文已进行过描述，在此不再赘述。
本实施例相对于现有技术而言，通过主动笔与触控屏之间形成的耦合电 容接收触控屏发送的DSSS信号，DSSS信号为经过扩频编码的待传输信号；主动笔对接收的DSSS信号进行解析，得到待传输信号。通过电容耦合的方式接收DSSS信号，可以很好地适用于触控系统中DSSS信号的传输。而且，本实施例中，只需要一级预放大电路、一级迟滞比较电路、一级数字解调电路就可以实现对接收的DSSS信号的解析，电路结构简洁，所需硬件资源较少，功耗较低，非常适合应用于对电路尺寸、功耗等有严格要求的主动笔与触控屏的交互系统中。
本申请第二实施例涉及一种信号传输方法，本实施方式主要对第一实施方式中步骤603的实现过程进行具体说明，也就是说，对具体如何通过数字解调电路对还原后的DSSS信号进行解调进行具体说明，数字解调电路可以采用相应的算法实现其相应的功能，具体算法的流程图，可参考图19所示，包括：
步骤701，通过数字解调电路对还原后的所述DSSS信号进行采样得到原始打码信号。
本实施例中以USI主动笔触控协议为例进行说明，具体的说，可以对迟滞比较电路输出的还原后的DSSS信号以N Mhz的采样频率进行采样得到原始打码信号signal1，原始打码信号signal1，包括第一类信号、第二类信号和第三类信号，第一类信号为待传输信号中的“0”所对应的扩频编码0x58F9A428，第二类信号为待传输信号中的“1”所对应的扩频编码0x27065BD4，第三类信号为无用信号。
步骤702，将原始打码信号与预设的自相关解调信号按位异或。
具体的说，可以在每采集到B位原始打码信号后，将自相关解调信号整体后移1位；其中，B为自相关解调信号的位数，即将自相关解调信号signal2 是作为一个整体在时间轴上移动，使采集到的原始打码信号都能与对应的自相关解调信号进行按位异或。自相关解调信号可以为第一类信号或第二类信号，本实施例中自相关解调信号以第一类信号为例，如图20所示，自相关解调信号signal2的波形图为“编码0”的波形图。由USI协议的DSSS信号特性，“0”或“1”都是以31bit的数据编码，且每个bit时长为1us，则每个bit采样得到的点数为N个，所以自相关解调信号signal2为31*N的波表存储。随着每个采样点被采入，按位平移自相关解调信号signal2，重复上述将原始打码信号signal1和自相关解调信号signal2按位异或。
步骤703，将按位异或的结果进行累加，得到累加结果。
具体地说，可以将B位原始打码信号与B位自相关解调信号按位异或的结果进行累加，得到累加结果。通常情况下，当signal1中的一段编码“1”信号与自相关信号signal2同步异或累加时，得到的结果接近31*N；当原始打码信号signal1中的一段编码“0”信号与自相关解调信号signal2同步异或累加时，得到的结果接近0；当原始打码信号signal1中的无用信号与自相关解调信号signal2异或累加时，得到的结果接近31*N/2。
步骤704，根据累加结果，对还原后的DSSS信号进行解调。
具体地说，可以根据累加结果分别与预设门限的比较结果，对还原后的DSSS信号进行解调。预设门限可以包括第一预设阈值和第二预设阈值，第二设阈值大于第一预设阈值。在实际应用中，第一预设阈值Threshold_L可以为大于或等于0，且小于或等于B*N/2的自然数，即0≤Threshold_L≤B*N/2。第二预设阈值Threshold_H可以为大于B*N/2，且小于或等于B*N的自然数，即B*N/2<Threshold_H≤B*N，其中，B为自相关解调信号的位数，由于本实施方 式中的自相关解调信号以31bit的数据编码为例，那么本实施方式中的B为31；N为数字解调电路对还原后的DSSS信号进行采样的采样频率。也就是说，在本实施例中0≤Threshold_L≤31*N/2，31*N/2<Threshold_H≤31*N。
进一步的，若检测到的累加结果小于或等于Threshold_L，则识别出B位原始打码信号为第一类信号；若检测到的累加结果大于或等于Threshold_H，则识别出B位原始打码信号为第二类信号；若检测到的累加结果大于Threshold_L且小于Threshold_H，则识别出B位原始打码信号为无用信号。为方便理解，可参考图20，若累加结果大于Threshold_H,可识别出编码1，若小于Threshold_L，可识别出编码0，若小于Threshold_H且大于Threshold_L可识别为无用信号。从图20中可以看出，T0、T1、T2、Tm、Tn时刻采样得到的都是无用信号，Tm+1时刻开始采样得到编码1、Tn+1时刻开始采样得到编码0。
在实际应用中，若检测的累加结果小于或等于第一预设阈值，则还可以将采集到B位原始打码信号的起始时刻作为识别出的第一类信号的起始时刻；若检测到的累加结果大于或等于第二预设阈值，则还可以将采集到B位原始打码信号的起始时刻作为识别出的第二类信号的起始时刻。为方便理解，可参考图22，若累加结果大于Threshold_H,可识别出编码1，并可以获悉此编码“1”的起始时刻为采集到该段原始打码信号的起始时刻，即图中标识的“有效信号编码1的起始时刻Tm+1”；若小于Threshold_L，可识别出编码0，并可以获悉此编码“0”的起始时刻为采集到该段原始打码信号的起始时刻，即图中标识的“有效信号编码0”的起始时刻Tn+1”。
本实施方式相对于现有技术而言，数字解调电路可将迟滞比较电路还原 出来的DSSS信号解析出来，并可同步此DSSS信号，检测到其起始时刻，实现触控屏与主动笔的时序同步，以更好的进行触控屏与主动笔之间的信息交互。
本申请第三实施例涉及一种信号传输方法，应用于触控屏，具体流程图如图21所示，包括：
步骤801，对待传输信号进行扩频编码生成DSSS信号。
步骤802，通过主动笔与触控屏之间形成的耦合电容将DSSS信号发送至主动笔，以供主动笔对接收的DSSS信号进行解析，得到待传输信号。
不难发现，本实施方式的信号传输方法应用于触控屏，第一和第二实施方式的信号传输方法应用于主动笔，本实施方式可与第一和第二实施方式互相配合实施。第一和第二实施方式中提到的相关技术细节在本实施方式中依然有效，为了减少重复，这里不再赘述。相应地，本实施方式中提到的相关技术细节也可应用在第一和第二实施方式中。
本实施方式相对于现有技术而言，通过主动笔与触控屏之间形成的耦合电容传输DSSS信号，可以很好地适用于触控系统中DSSS信号的传输。而且，本实施例中，只需要一级预放大电路、一级迟滞比较电路、一级数字解调电路就可以实现对接收的DSSS信号的解析，电路结构简洁，所需硬件资源较少，功耗较低，非常适合应用于对电路尺寸、功耗等有严格要求的主动笔与触控屏的交互系统中。
上面各种方法的步骤划分，只是为了描述清楚，实现时可以合并为一个步骤或者对某些步骤进行拆分，分解为多个步骤，只要包括相同的逻辑关系，都在本专利的保护范围内；对算法中或者流程中添加无关紧要的修改或者引入无关紧要的设计，但不改变其算法和流程的核心设计都在该专利的保护范围内。
本申请第四实施例涉及一种主动笔，如图22所示，包括：至少一个处理器901；以及，与至少一个处理器901通信连接的存储器902；其中，存储器902存储有可被至少一个处理器901执行的指令，指令被至少一个处理器901执行，以使至少一个处理器901能够执行上述应用于主动笔的信号传输方法。
其中，存储器902和处理器902采用总线方式连接，总线可以包括任意数量的互联的总线和桥，总线将一个或多个处理器和存储器902的各种电路连接在一起。总线还可以将诸如外围设备、稳压器和功率管理电路等之类的各种其他电路连接在一起，这些都是本领域所公知的，因此，本文不再对其进行进一步描述。总线接口在总线和收发机之间提供接口。收发机可以是一个元件，也可以是多个元件，比如多个接收器和发送器，提供用于在传输介质上与各种其他装置通信的单元。经处理器902处理的数据通过天线在无线介质上进行传输，进一步，天线还接收数据并将数据传送给处理器902。
处理器902负责管理总线和通常的处理，还可以提供各种功能，包括定时，外围接口，电压调节、电源管理以及其他控制功能。而存储器902可以被用于存储处理器902在执行操作时所使用的数据。
本申请第五实施例涉及一种触控屏，如图23所示，包括：至少一个处理器1001；以及，与至少一个处理器1001通信连接的存储器1002；其中，存储器1002存储有可被至少一个处理器1001执行的指令，指令被至少一个处理器1001执行，以使至少一个处理器1001能够执行上述应用于触控屏的信号传输方法。
其中，存储器1002和处理器1002采用总线方式连接，总线可以包括任意数量的互联的总线和桥，总线将一个或多个处理器和存储器1002的各种电路 连接在一起。总线还可以将诸如外围设备、稳压器和功率管理电路等之类的各种其他电路连接在一起，这些都是本领域所公知的，因此，本文不再对其进行进一步描述。总线接口在总线和收发机之间提供接口。收发机可以是一个元件，也可以是多个元件，比如多个接收器和发送器，提供用于在传输介质上与各种其他装置通信的单元。经处理器1002处理的数据通过天线在无线介质上进行传输，进一步，天线还接收数据并将数据传送给处理器1002。
处理器1002负责管理总线和通常的处理，还可以提供各种功能，包括定时，外围接口，电压调节、电源管理以及其他控制功能。而存储器1002可以被用于存储处理器1002在执行操作时所使用的数据。
本申请第六实施例涉及一种信号传输系统，如图24所示，包括：触控屏1101和主动笔1102。触控屏1101用于对待传输信号进行扩频编码生成DSSS信号；触控屏1101，还用于通过与主动笔1102之间形成的耦合电容1103将DSSS信号发送至主动笔1102；主动笔1102，用于对接收的DSSS信号进行解析，得到待传输信号。
不难发现，本实施方式为与第一、第二和第三实施方式相对应的系统实施例，本实施方式可与第一、第二和第三实施方式互相配合实施。第一、第二和第三实施方式中提到的相关技术细节在本实施方式中依然有效，为了减少重复，这里不再赘述。相应地，本实施方式中提到的相关技术细节也可应用在第一、第二和第三实施方式中。
本实施方式相对于现有技术而言，通过主动笔与触控屏之间形成的耦合电容传输DSSS信号，可以很好地适用于触控系统中DSSS信号的传输。而且，本实施例中，主动笔只需要一级预放大电路、一级迟滞比较电路、一级数字解 调电路就可以实现对接收的DSSS信号的解析，电路结构简洁，所需硬件资源较少，功耗较低，非常适合应用于对电路尺寸、功耗等有严格要求的主动笔与触控屏的交互系统中。
本申请第七实施例涉及一种芯片，如图25所示，包括：预放大电路1201，用于对通过所述主动笔与触控屏之间形成的耦合电容接收的所述触控屏发送的DSSS信号进行预放大，将预放大后的所述DSSS信号输出至迟滞比较电路1202；所述迟滞比较电路1202，用于对所述预放大后的所述DSSS信号进行还原，将还原后的所述DSSS信号输出至数字解调电路1203；所述数字解调电路1203，用于对还原后的DSSS信号进行解调。
在一个例子中，预放大电路1201可以为反相放大电路或同相放大电路，迟滞比较电路可以为：同向迟滞比较电路或反向迟滞比较电路。
在一个例子中，反相放大电路可以为如图6所示的低阻反向放大电路。低阻反向放大电路包括：第一运算放大器、第一反馈电阻RF1和第一反馈电容CF1；其中，第一运算放大器的同相输入端连接输入电压VCMI，且反向输入端连接DSSS信号。第一反馈电阻RF1跨接于第一运算放大器的反向输入端与输出端之间，第一反馈电容CF1与第一反馈电阻RF1并联。也就是说，第一反馈电阻RF1的第一端与第一运算放大器的反向输入端相连，且第二端与第一运算放大器的输出端相连。第一反馈电容CF1的第一端与第一反馈电阻RF1的第一端相连，且第二端与第一反馈电阻RF1的第二端相连。
在一个例子中，同相放大电路可以为如图8所示的高阻同向放大电路。高阻同向放大电路包括：第二运算放大器、第二反馈电阻RF2、第二反馈电容CF2、第一电阻R1和第二电阻R2；其中，第二运算放大器的同相输入端连接DSSS 信号，且反向输入端与第二电阻R2的第二端相连，第二电阻R2的第一端与第一输入电压VCMI1相连。第二反馈电阻RF2跨接于第二运算放大器的反相输入端与输出端之间，第二反馈电容CF2与第二反馈电阻RF2并联。也就是说，第二反馈电阻RF2的第一端与第二运算放大器的反向输入端相连，且第二端与第二运算放大器的输出端相连。第二反馈电容CF2的第一端与第二反馈电阻RF2的第一端相连，且第二端与第二反馈电阻RF2的第二端相连。第一电阻R1的第一端与第二运算放大器的同相输入端相连，且第二端与第二输入电压VCMI2连接，其中，VCMI1与VCMI2可以相同。
在一个例子中，同向迟滞比较电路的电路图可以如图10所示，包括：第一比较器、第三电阻R3、第四电阻R4和第五电阻R5；第三电阻R3的第一端与预放大电路的输出端V1相连，且第二端与第一比较器的同相输入端相连。第四电阻R4跨接于第一比较器的同相输入端与输出端之间。也就是说，第四电阻R4的第一端与第三电阻R3的第二端相连，且第二端与第一比较器的输出端V2相连。第五电阻R5的第一端与输入电压VCMI相连，且第二端与第一比较器的反向输入端连接。
在一个例子中，反向迟滞比较电路的电路图可以如图11所示，包括：第二比较器、第六电阻R6、第七电阻R7和第八电阻R8；其中，第六电阻R6的第一端与输入电压VCMI相连，且第二端与第二比较器的正向输入端连接。第七电阻R7跨接于第二比较器的同向输入端与输出端之间。也就是说，第七电阻R7的第一端与第六电阻R6的第二端相连，且第二端与第二比较器的输出端V2相连。第八电阻R8的第一端与预放大电路的输出端V1相连，且第二端与第二比较器的反向输入端相连。
本申请实施例相对于现有技术而言，通过主动笔与触控屏之间形成的耦合电容传输DSSS信号，可以很好地适用于触控系统中DSSS信号的传输。而且，本实施例中，只需要一级预放大电路、一级迟滞比较电路、一级数字解调电路就可以实现对接收的DSSS信号的解析，电路结构简洁，所需硬件资源较少，功耗较低，非常适合应用于对电路尺寸、功耗等有严格要求的主动笔与触控屏的交互系统中。
本申请第八实施例涉及一种主动笔，包括第七实施例中的芯片。
本申请第九实施方式涉及一种计算机可读存储介质，存储有计算机程序。计算机程序被处理器执行时实现上述信号传输方法实施例。
即，本领域技术人员可以理解，实现上述实施例方法中的全部或部分步骤是可以通过程序来指令相关的硬件来完成，该程序存储在一个存储介质中，包括若干指令用以使得一个设备(可以是单片机，芯片等)或处理器(processor)执行本申请各个实施例方法的全部或部分步骤。而前述的存储介质包括：U盘、移动硬盘、只读存储器(ROM，Read-Only Memory)、随机存取存储器(RAM，Random Access Memory)、磁碟或者光盘等各种可以存储程序代码的介质。
本领域的普通技术人员可以理解，上述各实施例是实现本申请的具体实施例，而在实际应用中，可以在形式上和细节上对其作各种改变，而不偏离本申请的精神和范围。

Claims (23)

  1. 一种信号传输方法，其特征在于，应用于主动笔，包括：
    通过所述主动笔与触控屏之间形成的耦合电容接收所述触控屏发送的DSSS信号；其中，所述DSSS信号为经过扩频编码的待传输信号；
    对接收的所述DSSS信号进行解析，得到所述待传输信号。
  2. 根据权利要求1所述的信号传输方法，其特征在于，所述对接收的所述DSSS信号进行解析，得到所述待传输信号，具体包括：
    通过预放大电路对接收的所述DSSS信号进行预放大；
    将预放大后的所述DSSS信号输入迟滞比较电路，通过所述迟滞比较电路对所述预放大后的所述DSSS信号进行还原；
    将还原后的所述DSSS信号输入数字解调电路，通过所述数字解调电路对所述还原后的所述DSSS信号进行解调，输出所述待传输信号。
  3. 根据权利要求2所述的信号传输方法，其特征在于，所述通过所述数字解调电路对所述还原后的所述DSSS信号进行解调，具体包括：
    通过所述数字解调电路对所述还原后的所述DSSS信号进行采样得到原始打码信号；
    将所述原始打码信号与预设的自相关解调信号按位异或；
    将所述按位异或的结果进行累加，得到累加结果；
    根据所述累加结果，对所述还原后的所述DSSS信号进行解调。
  4. 根据权利要求3所述的信号传输方法，其特征在于，所述将所述原始打码信号与预设的自相关解调信号按位异或，具体包括：
    每采集到B位原始打码信号后，将所述自相关解调信号整体后移1位；其中，所述B为所述自相关解调信号的位数；
    将所述B位原始打码信号与B位所述自相关解调信号按位异或；
    所述将所述按位异或的结果进行累加，得到累加结果，具体为：
    将所述B位原始打码信号与B位所述自相关解调信号按位异或的结果进行累加，得到累加结果；
    根据所述累加结果，对所述还原后的所述DSSS信号进行解调，具体为：
    根据所述累加结果与预设门限的比较结果，对所述还原后的所述DSSS信号进行解调。
  5. 根据权利要求4所述的信号传输方法，其特征在于，所述原始打码信号包括第一类信号、第二类信号和第三类信号，所述第一类信号为所述待传输信号中的“0”所对应的扩频编码，所述第二类信号为所述待传输信号中的“1”所对应的扩频编码，所述第三类信号为无用信号；
    若所述自相关解调信号为第一类信号，则所述根据所述累加结果与预设门限的比较结果，对所述还原后的所述DSSS信号进行解调，具体包括：
    若检测到所述累加结果小于或等于第一预设阈值，则识别出所述B位原始打码信号为第一类信号；
    若检测到所述累加结果大于或等于第二预设阈值，则识别出所述B位原始打码信号为第二类信号；其中，所述第二预设阈值大于所述第一预设阈值；
    若检测到所述累加结果大于所述第一预设阈值且小于所述第二预设阈值，则识别出所述B位原始打码信号为无用信号。
  6. 根据权利要求5所述的信号传输方法，其特征在于，若检测到所述累加 结果小于或等于第一预设阈值，则还包括：将采集到所述B位原始打码信号的起始时刻作为识别出的所述第一类信号的起始时刻；
    若检测到所述累加结果大于或等于第二预设阈值，则还包括：将采集到所述B位原始打码信号的起始时刻作为识别出的所述第二类信号的起始时刻。
  7. 根据权利要求5所述的信号传输方法，其特征在于，所述第一预设阈值大于或等于0，且小于或等于B*N/2；所述第二预设阈值大于所述B*N/2，且小于或等于B*N；其中，所述N为所述数字解调电路对所述还原后的所述DSSS信号进行采样的采样频率。
  8. 根据权利要求2所述的信号传输方法，其特征在于，所述预放大电路具体为：同相放大电路或反相放大电路。
  9. 根据权利要求2所述的信号传输方法，其特征在于，所述迟滞比较电路具体为：同向迟滞比较电路或反向迟滞比较电路。
  10. 根据权利要求1至9中任一项所述的信号传输方法，其特征在于，所述主动笔包括主电极和副电极，所述主动笔与触控屏之间形成的耦合电容具体为：
    所述主电极与所述触控屏之间形成的耦合电容，或者所述副电极与所述触控屏之间形成的耦合电容。
  11. 一种信号传输方法，其特征在于，应用于触控屏，包括：
    对待传输信号进行扩频编码生成DSSS信号；
    通过主动笔与所述触控屏之间形成的耦合电容将所述DSSS信号发送至所述主动笔，以供所述主动笔对接收的所述DSSS信号进行解析，得到所述待传输信号。
  12. 一种主动笔，其特征在于，包括：
    至少一个处理器；以及，
    与所述至少一个处理器通信连接的存储器；其中，
    所述存储器存储有可被所述至少一个处理器执行的指令，所述指令被所述至少一个处理器执行，以使所述至少一个处理器能够执行如权利要求1至10中任一所述的信号传输方法。
  13. 一种触控屏，其特征在于，包括：
    至少一个处理器；以及，
    与所述至少一个处理器通信连接的存储器；其中，
    所述存储器存储有可被所述至少一个处理器执行的指令，所述指令被所述至少一个处理器执行，以使所述至少一个处理器能够执行如权利要求11所述的信号传输方法。
  14. 一种信号传输系统，其特征在于，包括：触控屏和主动笔；
    所述触控屏，用于对待传输信号进行扩频编码生成DSSS信号；
    所述触控屏，还用于通过与所述主动笔之间形成的耦合电容将所述DSSS信号发送至所述主动笔；
    所述主动笔，用于对接收的所述DSSS信号进行解析，得到所述待传输信号。
  15. 一种计算机可读存储介质，存储有计算机程序，其特征在于，所述计算机程序被处理器执行时实现权利要求1至11中任一项所述的信号传输方法。
  16. 一种芯片，其特征在于，包括：
    预放大电路，用于对通过所述主动笔与触控屏之间形成的耦合电容接收的所述触控屏发送的DSSS信号进行预放大，将预放大后的所述DSSS信号输出至 迟滞比较电路；
    所述迟滞比较电路，用于对所述预放大后的所述DSSS信号进行还原，将还原后的所述DSSS信号输出至数字解调电路；
    所述数字解调电路，用于对还原后的DSSS信号进行解调。
  17. 根据权利要求16所述的芯片，其特征在于，所述预放大电路为：反相放大电路或同相放大电路。
  18. 根据权利要求17所述的芯片，其特征在于，所述反相放大电路包括：第一运算放大器、第一反馈电阻和第一反馈电容；
    所述第一运算放大器的同相输入端连接输入电压，且反向输入端连接所述DSSS信号；
    所述第一反馈电阻跨接于所述第一运算放大器的反向输入端与输出端之间；
    所述第一反馈电容与所述第一反馈电阻并联。
  19. 根据权利要求17所述的芯片，其特征在于，所述同相放大电路包括：第二运算放大器、第二反馈电阻、第二反馈电容、第一电阻和第二电阻；
    所述第二运算放大器的同相输入端连接所述DSSS信号，且反向输入端与所述第二电阻的第二端相连；其中，所述第二电阻的第一端与第一输入电压相连；
    所述第二反馈电阻跨接于所述第二运算放大器的反相输入端与输出端之间；
    所述第二反馈电容与所述第二反馈电阻并联；
    所述第一电阻的第一端与所述第二运算放大器的同相输入端相连，且第二端与第二输入电压连接。
  20. 根据权利要求16所述的芯片，其特征在于，所述迟滞比较电路为同向迟滞比较电路或反向迟滞比较电路。
  21. 根据权利要求20所述的芯片，其特征在于，所述同向迟滞比较电路包括：第一比较器、第三电阻、第四电阻和第五电阻；
    所述第三电阻的第一端与所述预放大电路的输出端相连，且第二端与所述第一比较器的同相输入端相连；
    所述第四电阻跨接于所述第一比较器的同相输入端与输出端之间；
    所述第五电阻的第一端与输入电压相连，且第二端与所述第一比较器的反向输入端连接。
  22. 根据权利要求20所述的芯片，其特征在于，所述反向迟滞比较电路包括：第二比较器、第六电阻、第七电阻和第八电阻；
    所述第六电阻的第一端与输入电压相连，且第二端与所述第二比较器的正向输入端连接；
    所述第七电阻跨接于所述第二比较器的同向输入端与输出端之间；
    所述第八电阻的第一端与所述预放大电路的输出端相连，且第二端与所述第二比较器的反向输入端相连。
  23. 一种主动笔，包括如权利要求16至22中任一项所述的芯片。
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116048289A (zh) * 2022-08-25 2023-05-02 荣耀终端有限公司 手写笔的出水控制方法及电子设备

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2022165839A1 (zh) * 2021-02-08 2022-08-11 深圳市汇顶科技股份有限公司 抗干扰的方法、触控芯片及主动笔芯片

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN203084673U (zh) * 2013-01-23 2013-07-24 成都有形科技有限公司 主动式电容笔
CN103941889A (zh) * 2014-03-17 2014-07-23 汉王科技股份有限公司 电容笔、电容触控面板和触控装置
CN105468170A (zh) * 2014-08-13 2016-04-06 比亚迪股份有限公司 电容笔与触摸屏之间的数据传输方法、系统和装置
CN107066122A (zh) * 2015-12-31 2017-08-18 乐金显示有限公司 有源触控笔、触摸感测系统及其驱动方法

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11392221B2 (en) * 2013-11-08 2022-07-19 Egalax_Empia Technology Inc. Touch sensitive processing apparatus, system and operating method thereof for receiving electrical signals carrying pressure information
JP6445883B2 (ja) * 2015-01-30 2018-12-26 東芝メモリ株式会社 受信回路及び通信システム
TWI563418B (en) * 2015-10-16 2016-12-21 Waltop Int Corp Signal decoding and modulation processing system for capacitive stylus
US10324547B2 (en) * 2015-12-31 2019-06-18 Lg Display Co., Ltd. Active stylus pen, touch sensing system and driving method thereof
CN107969152A (zh) * 2016-08-26 2018-04-27 深圳市汇顶科技股份有限公司 信号发射方法、信号解析方法、主动笔及触控屏
CN109521893B (zh) * 2018-10-17 2022-11-25 京东方科技集团股份有限公司 触控笔、触控面板、触控感测系统及其控制方法

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN203084673U (zh) * 2013-01-23 2013-07-24 成都有形科技有限公司 主动式电容笔
CN103941889A (zh) * 2014-03-17 2014-07-23 汉王科技股份有限公司 电容笔、电容触控面板和触控装置
CN105468170A (zh) * 2014-08-13 2016-04-06 比亚迪股份有限公司 电容笔与触摸屏之间的数据传输方法、系统和装置
CN107066122A (zh) * 2015-12-31 2017-08-18 乐金显示有限公司 有源触控笔、触摸感测系统及其驱动方法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP3764203A4 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116048289A (zh) * 2022-08-25 2023-05-02 荣耀终端有限公司 手写笔的出水控制方法及电子设备

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