TWM575147U - Radio frequency identification system with multiple induction coils - Google Patents

Abstract

A multi-induction coil radio frequency identification system includes a plurality of radio frequency reading modules and a main controller. A plurality of radio frequency reading modules are adapted to operate in a transmitting resonant mode and an idle mode. The radio frequency reading module comprises: an induction coil for transmitting a detection signal when transmitting the resonance mode, and generating a resonance signal according to the response signal, generating an induction signal according to the response signal in the idle mode; the resonance circuit electrically connecting the induction coil The method is used for responding to the induction coil; and the switch circuit is electrically connected to the resonant circuit. When the conduction is performed, the RF reading module is controlled to operate in the resonant mode, and the RF reading module is controlled to operate in the idle mode when the circuit is disconnected. The main controller is electrically connected to the induction coil and the switch circuit for controlling the switch circuit to be turned on or off, and controlling the induction coil to emit the detection signal.

Description

Multi-induction coil radio frequency identification system

The present invention relates to a radio frequency identification system for a multi-induction coil.

Radio Frequency Identification (RFID) system is a wireless communication data transmission technology that can identify specific targets and read and write related data through radio signals without establishing mechanical or optical contact between the RFID system and specific targets. The system is mainly composed of a tag, a reader and a processor. The tag includes an integrated circuit and an antenna, which can store various identification information, and transmit the data to the reader through a radio signal through the antenna, and are classified into a passive, semi-passive and active tag according to whether the tag itself has a battery source. The reader includes a Transmitter, a Receiver, and an antenna. The Transmitter transmits the processor's signal through the antenna and provides ambient AC power to the tag. The receiver is responsible for receiving the signal transmitted by the tag and handing over the signal to the processor.

In daily life, the RFID system has been widely used to track people, things, and objects, including identity documents, electronic tickets, logistics management, baggage classification, and access control systems. However, today's single RFID system cannot identify different tags at the same time in a single area, and cannot be completed by a single system in different areas. It still needs a regional setting of a set of RFID systems, that is, a reader needs to be combined with a control. Therefore, it is costly and practically limited.

In view of the above, the present invention proposes a multi-induction coil radio frequency identification system, comprising a plurality of radio frequency reading modules and a main controller. A plurality of radio frequency reading modules are adapted to operate in a transmit resonant mode and an idle mode. Each RF reading module includes an induction coil, a resonant circuit, and a switching circuit. The resonant circuit is electrically connected to the induction coil, the switch circuit is electrically connected to the resonant circuit, and the main controller is electrically connected to the plurality of induction coils and the plurality of switch circuits. The induction coil is configured to emit a detection signal when transmitting the resonance mode, and generate a resonance signal according to a response signal. In the idle mode, the induction coil generates an inductive signal according to the response signal. A resonant circuit is used to respond to the induction coil. When the switching circuit is turned on, the radio frequency reading module is controlled to operate in the transmitting resonance mode. When the switch circuit is open circuit, the radio frequency reading module is controlled to operate in the idle mode. The main controller is used to control multiple switching circuits to be turned on or off, and control multiple sensing coils to emit multiple detecting signals.

In an embodiment, each of the radio frequency reading modules further includes a demodulation circuit. The demodulation circuit is electrically connected to the resonance circuit. In the transmit resonant mode, the demodulation circuit demodulates the resonant signal and outputs a first data signal. In the idle mode, the demodulation circuit demodulates the variable sensing signal and outputs a second data signal.

In an embodiment, the multi-induction coil radio frequency identification system further includes an amplifying circuit. The amplifying circuit is electrically connected between the demodulation circuit and the main controller. The amplifying circuit is configured to calculate and amplify the first data signals and the second data signals of the demodulation circuits, and combine and output an amplified signal.

In an embodiment, the main controller includes an arithmetic processing circuit. The main controller is electrically connected to the amplifying circuit for generating an operation signal in response to the amplified signal of the amplifying circuit.

In an embodiment, the main controller further includes a control circuit. The main controller is electrically connected to the arithmetic processing circuit. The main controller selectively outputs a plurality of control signals according to the operation signals of the operation processing circuit to control the switch circuits.

In an embodiment, the multi-induction coil radio frequency identification system further includes a driving circuit. The driving circuit is electrically connected between the main controller and the plurality of induction coils. The driving circuit controls one of the plurality of induction coils to emit a plurality of detection signals according to one of the output signals of the main controller.

In an embodiment, each of the RF reading modules further includes an isolation circuit. The isolation circuit is electrically connected between the demodulation circuit and the amplification circuit. The isolation circuit is used to reduce noise between the demodulation circuit and the amplification circuit.

In an embodiment, the multi-induction coil radio frequency identification system further includes at least one audio playback circuit. The at least one audio playback circuit is electrically connected to the control circuit. The control circuit outputs an indication signal in response to the operation signal, and the at least one audio playback circuit outputs a corresponding audio in response to the indication signal.

In an embodiment, the radio frequency identification system of the induction coil further includes an input and output device. The input and output devices are electrically connected to the control circuit. The control circuit responds to the operation signal output indication signal, and the input/output device outputs a corresponding input/output signal in response to the indication signal.

In one embodiment, the radio frequency reading modules are arranged in an array, and the magnetic poles of the two adjacent sensing coils are in reverse phase.

In an embodiment, the multi-induction coil radio frequency identification system further includes at least one radio frequency tag. The RF tag is used to receive the detection signal and transmit the response signal according to the detection signal.

Please refer to FIG. 1, which illustrates a schematic diagram of a multi-inductance coil radio frequency identification system 10. In some embodiments, the multi-inductive coil radio frequency identification system 10 includes a plurality of radio frequency reading modules 20 and a main controller 30, and can read at least one radio frequency tag 60. The main controller 30 is electrically connected to each of the radio frequency reading modules 20 to simultaneously control the radio frequency reading modules 20, and the radio frequency reading modules 20 and the radio frequency tags 60 are connected by transmitting and receiving radio frequency signals. Each of the RF reading modules 20 can transmit a detection signal S _out and receive a response signal S _in . In contrast, the RF tag 60 is configured to receive the detection signal S _{out of the} RF reading module 20 and according to the detection. The signal S _out transmits a corresponding response signal S _in .

Please refer to FIG. 2A , which illustrates a schematic diagram of the radio frequency reading module 20 . In some embodiments, the RF reading module 20 includes an induction coil 202, a resonant circuit 204, and a switching circuit 206. The induction coil 202 has an input end 202A and an output end 202B. The resonant circuit 204 has a sensing end 204A and a switching end 204B. The switching circuit 206 has a control end 206A. The input end 202A and the output end 202B of the induction coil 202 are electrically connected to the main controller 30, and the sensing end 204A of the resonant circuit 204 is electrically connected between the output end 202B of the induction coil 202 and the main controller 30. The switch circuit 206 is electrically connected between the switch terminal 204B of the resonant circuit 204 and a reference potential terminal 206B, and the control terminal 206A of the switch circuit 206 is electrically connected to the main controller 30. The potential of the reference potential terminal 206B is sufficient for the resonant circuit 204 and the induction coil 202 to respond to form a loop, such as a ground potential or a high potential.

Please refer to FIG. 2B, FIG. 2C and FIG. 2D. FIG. 2B is a schematic diagram showing the emission of the radio frequency reading module 20 operating in the resonant mode, and FIG. 2C is a radio frequency reading mode operating in the transmitting resonant mode. A schematic diagram of the resonance of group 20, and FIG. 2D depicts a schematic diagram of radio frequency reading module 20 operating in an idle mode. The implementation of each RF reading module 20 is substantially the same. The operation of an RF reading module 20 is as follows: The RF reading module 20 is operable in a transmit resonant mode and an idle mode. In the resonant mode, the inductive coil 202 is used to transmit the detection signal S _out and the inductive coil 202 is also used to generate a resonant signal S6 _in response to a response signal S _in . The induction coil 202 reaches the function of transmitting the detection signal S _out and responding to the response signal S _in a time sharing manner. In the idle mode, the induction coil 202 is responsive to the response signal S _in to generate an inductive signal S4.

In some embodiments, the induction coil 202 functions to continuously generate an induced magnetic field (not shown) to achieve the time-division detection signal S _out and the response signal S _in .

In some embodiments, the induction coil 202 responds to the response signal S _in after transmitting the detection signal S _out .

Specifically, the radio frequency reading module 20 operates in a transmitting resonant mode or an idle mode according to the control of the main controller 30. When the induction coil 202 emits the detection signal _Sout , the induction coil 202 can be used to detect a to-be-detected object (for example, the radio frequency tag 60) within the sensing range. On the other hand, when the response signal S _{in the} object to be detected (for example, the radio frequency tag 60) is sent, the induction coil 202 generates a resonance signal S6, and in the idle mode, the induction coil 202 generates an inductive signal S4. .

It should be noted that the resonant circuit 204 of the present embodiment is configured to respond to the inductive coil 202 to form a resonant loop between the resonant circuit 204 and the inductive coil 202. When the RF reading module 20 operates in the transmitting resonant mode, the resonant circuit 204 transmits the detection signal S _{out in} response to the induction coil 202, and the resonant circuit 204 can also respond to the induction coil 202 to generate the resonant signal S6 according to the response signal S _in . When the RF reading module 20 is operated in the idle mode, the resonant circuit 204 and the induction coil 202 cannot form a resonant circuit. Therefore, the sensing coil 202 can only generate the sensing signal S4 according to the response signal S _in .

The mode of operation of the RF reading module 20 is determined by the switching circuit 206, or more specifically, whether the resonant circuit 204 is responsive to the induction coil 202 is controlled by the switching circuit 206. When the main controller 30 controls the switch circuit 206 to be turned on, the radio frequency reading module 20 will operate in the resonant mode, and the resonant circuit 204 can respond to the inductive coil 202. When the main controller 30 controls the switch circuit 206 to be open, the radio frequency reading module 20 will operate in the idle mode, and the resonant circuit 204 will not respond to the inductive coil 202. Specifically, when the switch circuit 206 is turned on, since the resonant circuit 204 and the reference potential terminal 206B are turned on, a resonant loop can be formed between the resonant circuit 204 and the induction coil 202. The detection signal S _out generated by the resonant circuit 204 and the induction coil 202 is generated by the induction coil 202. The resonant circuit 204 and the resonant coil S6 generated by the resonant coil 202 according to the response signal S _in are sent to the main controller 30. When the switch circuit 206 is open circuit, since only the sensing terminal 204A of the resonant circuit 204 is electrically connected to the output terminal 202B of the induction coil 202, that is, only one end of the resonant circuit 204 is electrically connected to the output terminal 202B of the induction coil 202 and the main controller. Between 30. Therefore, the resonant circuit 204 cannot respond to the induction coil 202 at this time, and the sensing signal S4 outputted at the output end 202B of the induction coil 202 is directly transmitted to the main controller 30.

In some embodiments, the embodiment of the present invention that causes the switching circuit 206 to be open is not limited to the case where no current flows between the resonant circuit 204 and the reference potential terminal 206B, and includes other causes that the resonant circuit 204 cannot respond to the induction coil. 202 case. For example, the resonant circuit 204 and the reference potential terminal 206B are coupled to at least one passive component having a corresponding impedance value (the passive component may be a resistor, a capacitor or an RC circuit) to break the resonant circuit between the resonant circuit 204 and the induction coil 202. .

Referring to FIG. 2C and FIG. 2D simultaneously, in some embodiments, each radio frequency reading module 20 further includes a demodulation circuit 208. The demodulation circuit 208 is electrically connected between the output terminal 202B of the induction coil 202 and the main controller 30, that is, one end of the demodulation circuit 208 is electrically connected to the sensing terminal 204A of the resonance circuit 204, and the demodulation circuit 208 The other end is electrically connected to the main controller 30. In the transmit resonant mode, the demodulation circuit 208 demodulates the variable resonant signal S6 and outputs a first data signal S8. In the idle mode, the demodulation circuit 208 demodulates the variable sensing signal S4 and outputs a second data signal S10. Specifically, the demodulation circuit 208 is configured to demodulate the original signal synthesized with the carrier into an original signal to facilitate the analysis process by the main controller 30. Therefore, the demodulation circuit 208 performs corresponding demodulation processing according to the received signal, and outputs the demodulated signal to the main controller 30. In some embodiments, since the sensing signal S4 does not pass the resonant response of the resonant circuit 204, the signal level of the sensing signal S4 is less than the signal level of the resonant signal S6, and thus the signal of the second data signal S10 corresponding to the sensing signal S4. The magnitude is also smaller than the first data signal S8 corresponding to the aforementioned resonant signal S6.

Referring to FIG. 1 , FIG. 2C and FIG. 2D , in some embodiments, the multi-inductance coil radio frequency identification system 10 further includes an amplifying circuit 40 and a driving circuit 50 . The amplifying circuit 40 is electrically connected between each demodulation circuit 208 and the main controller 30 for calculating and amplifying each of the first data signals S8 and the second data signals S10 of the respective demodulation circuits 208, and combining outputs. An amplification signal S12. In other words, the signal output by each demodulation circuit 208 may be the first data signal S8 or the second data signal S10, and the amplification circuit 40 performs amplification processing on the signals output by the respective demodulation circuits 208. Each of the signals after the demodulation processing is integrated by the amplifying circuit 40 into an amplified signal S12, and the amplifying circuit 40 outputs the amplified signal S12.

The driving circuit 50 is electrically connected between the main controller 30 and the respective induction coils 202. The driving circuit 50 outputs one of the RF signals S0 according to the main controller 30 to control the respective sensing coils 202 to emit respective detection signals _Sout . Specifically, the drive circuit 50 is electrically coupled between the main controller 30 and the input 202A of each of the induction coils 202. The driving circuit 50 outputs a driving signal S2 corresponding to each of the induction coils 202 according to the RF signal S0 outputted by the main controller 30, and each of the induction coils 202 transmits the detection signal S _out according to the driving signal S2. Specifically, the driving circuit 50 can control the induction coil 202 to emit the detection signal S _out when the radio frequency reading module 20 in which the induction coil 202 is located is operated in the transmission resonance mode. On the contrary, when the RF reading module 20 in which the induction coil 202 is located is operated in the idle mode, the induction coil 202 cannot transmit the detection signal S _out .

Referring to FIG. 1 , FIG. 2C and FIG. 2D , in some embodiments, the main controller 30 includes an arithmetic processing circuit 302 and a control circuit 304 . The arithmetic processing circuit 302 is electrically connected to the amplifying circuit 40 for generating an arithmetic signal S14 in response to the amplified signal S12 of the amplifying circuit 40. Specifically, the operation processing circuit 302 is configured to receive and calculate the processed amplification signal S12. The operation processing circuit 302 generates a corresponding operation signal S14 by identifying how many first data signals S8 are present in the amplification signal S12. Therefore, the main controller 30 can recognize how many response signals S _{in the} plurality of radio frequency reading modules 20 receive at the same time via the foregoing operation signal S14.

The control circuit 304 is electrically connected to the operation processing circuit 302, and selectively outputs a plurality of control signals according to the operation signal S14 of the operation processing circuit 302 to control the respective switch circuits 206. In other words, the main controller 30 can dynamically control the respective switch circuits 206 according to the receiving conditions of the plurality of radio frequency reading modules 20, and the main controller 30 can also take the initiative according to the receiving conditions of the plurality of radio frequency reading modules 20. Each switch circuit 206 is controlled locally. In some embodiments, the main controller 30 can dynamically control each of the switch circuits 206, and the main controller 30 can further confirm the respective RF read modules 20 _in which the response signals S _in are sequentially located, so that the main controller 30 can know Respond to the location of the signal S _in .

In some embodiments, the main controller 30 can actively control the operation of each radio frequency reading module 20 in order to control the functions of the respective radio frequency reading modules 20 in a time-sharing manner. For example, the main controller 30 sequentially controls each radio frequency reading module 20 to operate in a transmitting resonant mode, and controls the radio frequency reading module 20 to first transmit the detecting signal S _out , and then causes the radio frequency reading module 20 to respond to the corresponding response. Signal S _in .

Referring to FIG. 2A, in some embodiments, each radio frequency reading module 20 includes an isolation circuit 210. The isolation circuit 210 is electrically connected between the demodulation circuit 208 and the amplifying circuit 40. The isolation circuit 210 is configured to reduce noise between the demodulation circuit 208 and the amplifying circuit 40. Specifically, since the amplifying circuit 40 needs to be electrically connected to each demodulation circuit 208, the isolation circuit 210 prevents the respective demodulation circuits 208 from being interfered by the signals of the other demodulation circuits 208, and is protected from the amplifying circuit 40. Noise interference. In contrast, the isolation circuit 210 can also avoid the noise in the single demodulation circuit 208 from affecting the amplification circuit 40 and other demodulation circuits 208.

Please refer to FIG. 3, which illustrates a schematic diagram of a radio frequency identification system 10 having multiple inductive coils for audio playback. In some embodiments, the multi-inductance coil radio frequency identification system 10 further includes at least one audio playback circuit 70, and the audio playback circuit 70 is electrically connected to the main controller 30. The control circuit 304 outputs an indication signal S16 in response to the operation signal S14, and the audio playback circuit 70 outputs a corresponding audio in response to the indication signal S16. For example, the audio may include sound effects, music, dialogue, and the like. Specifically, the control circuit 304 in the main controller 30 outputs the indication signal S16 to the audio playback circuit 70 by recognizing which radio frequency reading module 20 receives the response signal S _in , and the audio playback circuit 70 according to the indication signal S16 The corresponding audio is output, so that the RFID system 10 that achieves multiple induction coils can interact according to the response signals S _in different positions.

According to some embodiments, the radio frequency identification system 10 of the induction coil further includes an input and output device (not shown). The input and output devices are electrically connected to the control circuit 304. The control circuit 304 outputs an indication signal S16 in response to the operation signal S14, and the input/output device outputs a corresponding input/output signal (I/O signal) in response to the indication signal S16. The input and output device is, for example but not limited to, an action device, a display device, or a multimedia device.

Please refer to FIG. 4 , which illustrates a schematic diagram of the RF read module 20 arranged in an array manner. In some embodiments, the RF reading modules 20 are arranged in an array, and the magnetic poles of the two adjacent sensing coils 202 are opposite in phase. Specifically, the detection signal S _out emitted by each of the induction coils 202 is considered to form a closed magnetic line loop in the space, and the magnetic lines of force pass through the adjacent induction coils 202. Therefore, by the inversion of the magnetic poles of the two adjacent induction coils 202, the detection signals _Sout emitted by the induction coil 202 do not cancel each other _out . In the size of the induction coil 202, since the small-area induction coil 202 has relatively easy to adjust operating parameters, and has a better electromagnetic wave energy distribution in the respective detection regions of the induction coil 202. By simultaneously activating the small-area induction coils 202 uniformly arranged in the array, the array has a uniform electromagnetic wave energy distribution to achieve the advantage of large-area sensing. When the RF tag 60 is placed in any position in the array, the RF tag 60 can obtain an energy-sensing sensing signal S4 to prevent the RF tag 60 from being driven to respond to the corresponding response signal S _in because the sensing signal S4 is too small.

Referring to FIG. 2A, in some embodiments, each radio frequency reading module 20 includes a diode D1 electrically connected between the resonant circuit 204 and the demodulation circuit 208 to limit the resonant circuit 204 and the solution. The direction of the current of the signal between the modulation circuits 208, so that the direction of the current of the signal can only flow from the resonant circuit 204 to the demodulation circuit 208.

Referring to FIG. 2A, in some embodiments, each demodulation circuit 208 includes a resistor R1 and a capacitor C1, and one end of the resistor R1 and one end of the capacitor C1 are electrically connected to a ground GND, thus solving The modulation circuit 208 can form a loop for the function of demodulation.

Referring to FIG. 2A, in an embodiment, each resonant circuit 204 can include a capacitor C2, and each isolation circuit 210 can include a capacitor C3.

Referring to FIG. 2A, in an embodiment, each of the induction coils 202 is an inductor, and in another embodiment, each of the induction coils 202 is an antenna.

In summary, according to the multi-induction coil radio frequency identification system 10 of the present invention, the main controller 30 controls each switch circuit 206 to switch the functions of each radio frequency reading module 20, and each radio frequency reading module is enabled. 20 each operates in a transmit resonant mode and an idle mode. In some embodiments, the multi-inductive coil radio frequency identification system 10 can generate corresponding interactions according to different positions of the response signal S _in . In other embodiments, the multi-induction coil radio frequency identification system 10 is arranged in an array to achieve the advantage of large-area sensing.

10‧‧‧Multi-induction coil radio frequency identification system

20‧‧‧RF reading module

30‧‧‧Main controller

40‧‧‧Amplification circuit

50‧‧‧ drive circuit

60‧‧‧RF tags

70‧‧‧Audio playback circuit

202‧‧‧Induction coil

202A‧‧‧ input

202B‧‧‧output

204‧‧‧Resonance circuit

204A‧‧‧Sensor

204B‧‧‧Switch end

206‧‧‧Switch circuit

206A‧‧‧Control terminal

206B‧‧‧reference potential

208‧‧‧Demodulation circuit

210‧‧‧Isolation circuit

302‧‧‧Operation Processing Circuit

304‧‧‧Control circuit

C1-C3‧‧‧ capacitor

R1‧‧‧Resistors

D1‧‧‧ diode

GND‧‧‧ ground terminal

S _out ‧‧‧Detection signal

S _in ‧‧‧Response signal

S0‧‧‧RF signal

S2‧‧‧ drive signal

S4‧‧‧ induction signal

S6‧‧‧Resonance signal

S8‧‧‧First data signal

S10‧‧‧Second information signal

S12‧‧‧Amplified signal

S14‧‧‧Operation signal

S16‧‧‧ indication signal

FIG. 1 is a schematic diagram of a radio frequency identification system of a plurality of induction coils of the present invention. 2A is a schematic diagram of the radio frequency reading module of the present invention. 2B is a schematic diagram of the transmission of the radio frequency reading module operating in the resonant mode of the present invention. 2C is a schematic diagram of the resonance of the radio frequency reading module operating in the resonant mode of the present invention. 2D is a schematic diagram of the radio frequency reading module operating in the idle mode of the present invention. FIG. 3 is a schematic diagram of a radio frequency identification system of a multi-induction coil having an audio playback function according to the present invention. FIG. 4 is a schematic diagram of an RF reading module arranged in an array manner of the present invention.

Claims (10)

A radio frequency identification system for a multi-inductance coil includes: a plurality of radio frequency reading modules adapted to operate in a transmit resonant mode and an idle mode, each of the radio frequency reading modules comprising: an inductive coil at which the radiating resonance In the mode, the induction coil is configured to emit a detection signal and generate a resonance signal according to a response signal. In the idle mode, the induction coil generates an induction signal according to the response signal; a resonant circuit and an electrical connection The induction coil is configured to be responsive to the induction coil; and a switch circuit electrically connected to the resonant circuit, wherein when the switch circuit is turned on, the RF read module is controlled to operate in the transmit resonant mode, wherein the switch circuit is When the circuit is disconnected, the RF reading module is controlled to operate in the idle mode; and a main controller electrically connects the induction coils and the switching circuits for controlling the switching circuits to be turned on or off, and controlled The induction coils emit the detection signals. The radio frequency identification system of the multi-induction coil of claim 1, wherein each of the radio frequency reading modules further comprises a demodulation circuit electrically connected to the resonance circuit, and the demodulation is changed in the transmission resonance mode. The circuit demodulates the resonant signal and outputs a first data signal. In the idle mode, the demodulation circuit demodulates the sensing signal and outputs a second data signal. The radio frequency identification system of the multi-induction coil of claim 2, further comprising an amplifying circuit electrically connected between the demodulation circuit and the main controller for calculating and amplifying the demodulation and transformation The first data signal and the second data signal of the road are combined to output an amplified signal. The radio frequency identification system of the multi-induction coil of claim 3, wherein the main controller comprises an arithmetic processing circuit electrically connected to the amplifying circuit for generating an operational signal in response to the amplified signal of the amplifying circuit. The radio frequency identification system of the multi-inductance coil of claim 4, wherein the main controller further comprises a control circuit electrically connected to the operation processing circuit, and selectively outputting the plurality of operation signals according to the operation processing circuit Control signals to control the switching circuits. The radio frequency identification system of the multi-induction coil of claim 5, further comprising a driving circuit electrically connected between the main controller and the induction coils, wherein the driving circuit is based on the main control The device outputs an RF signal to control the induction coils to transmit the detection signals. The radio frequency identification system of the multi-inductance coil of claim 6, wherein each of the radio frequency reading modules further comprises an isolation circuit electrically connected between the demodulation circuit and the amplifying circuit, wherein the isolation circuit is The noise between the demodulation circuit and the amplifying circuit is reduced. The radio frequency identification system of the multi-induction coil of claim 7, further comprising at least one audio playback circuit electrically connected to the control circuit, the control circuit outputting an indication signal in response to the operation signal, the at least one audio playback circuit responding to the indication The signal outputs a corresponding audio. The radio frequency identification system of the multi-inductance coil of any one of claims 1-8, wherein the radio frequency reading modules are arranged in an array, and the magnetic poles of the two adjacent two induction coils are opposite in phase. The radio frequency identification system of the multi-inductor coil of any one of claims 1-8, further comprising at least one radio frequency tag for receiving the detection signal and transmitting the response signal according to the detection signal.