CN103888256B - The authentication method and system of a kind of cipher key - Google Patents

Abstract

The invention belongs to the reliability transmission design field of voice data, there is provided the authentication method and system of a kind of cipher key.In this method and system, mobile terminal at least sends sonic detection signal twice to cipher key, and the sonic detection signal returned to cipher key last time matches, if the match is successful, transmits transaction data.The mode being authenticated relative to the existing voice data sent only for mobile terminal, the transmission voice data that this method and system can be more safe and reliable, the safety of guarantee subsequent transaction data.

Description

A cryptographic key authentication method and system

technical field

The invention belongs to the field of reliable transmission design of audio data, and in particular relates to an authentication method and system of a cryptographic key.

Background technique

With the rapid development of the mobile Internet and the widespread popularity of mobile terminals such as smartphones, banks have launched mobile banking services one after another. Users can log in to mobile banking through the client installed on the mobile terminal to realize functions such as online payment.

The digital certificate used in traditional online banking is usually a USB Key that can be connected to a personal computer. The USB Key is connected to the personal computer through a USB interface. Compared with the personal computer, the USB Key is equivalent to a slave device, while the existing The USB interface on the mobile terminal is also a slave device, and the USB technology requires that the two USB devices connected to each other must be a master device and a slave device, so the traditional USBKey cannot be directly connected to the USB interface of the mobile terminal.

For this reason, the prior art proposes a cryptographic key based on audio data transmission. The cryptographic key is connected to the mobile terminal in a wired or wireless manner, and signs the transaction data output by the mobile terminal in audio form. In order to ensure the security of data transmission, before the mobile terminal transmits transaction data with the wired password key, it needs to perform security authentication on the wired password key. The typical method of this authentication process is: after the mobile terminal modulates the PIN code entered by the user into audio data , and send it to the wired password key. After the wired password key demodulates the audio data, extracts the PIN code and authenticates the PIN code. If the authentication is passed, the transaction data will be transmitted; if the authentication is not passed, an error will be reported. However, under this authentication method, the wired encryption key only authenticates the audio data sent by the mobile terminal once, so the security is still poor, and the security, reliability and correctness of transaction data transmission cannot be guaranteed, which limits the application range of the encryption key.

Contents of the invention

The purpose of the embodiments of the present invention is to provide an authentication method for a cryptographic key, which aims to solve the problem that in the prior art, the wired cryptographic key only authenticates one audio data sent by the mobile terminal, which cannot guarantee the security, reliability and correctness of transaction data transmission. sex issue.

The embodiment of the present invention is achieved in this way, a cryptographic key authentication method, said method comprising:

Step S1: Before transmitting the transaction data, control the sound wave detection signal to be sent and received at least twice between the mobile terminal and the encryption key, and when the mobile terminal sends the sound wave detection signal to the encryption key this time, When receiving the sound wave detection signal returned by the encryption key, control the mobile terminal to send the next sound wave detection signal to the encryption key;

Step S2: When controlling the mobile terminal to receive the acoustic wave detection signal for the last time, control the mobile terminal to match the last received acoustic wave detection signal, and if the matching is successful, control the mobile terminal to A cryptographic key transmits said transaction data.

Another object of the embodiments of the invention is to provide an encryption key, which includes:

The first receiving module is used to receive the acoustic wave detection signal sent by the mobile terminal;

A modulation module, configured to modulate the received sound wave detection signal to a selected sound frequency point by adopting a preset modulation method;

A second sending module, configured to send the acoustic wave detection signal modulated by the modulating module to the mobile terminal;

The sound control module is configured to perform dual-band sound control on the matched sound wave detection signal received by the first receiving module and sent by the mobile terminal, and pass the sound control sound wave detection signal through the second The sending module sends to the mobile terminal.

Another object of the embodiments of the invention is to provide a mobile terminal, which includes:

The first sending module is used to send the sound wave detection signal to the encryption key;

The second receiving module is used to receive the modulated sound wave detection signal sent by the encryption key;

A demodulation module, configured to demodulate the sound wave detection signal received by the second receiving module, and if the demodulated sound wave detection signal is the same as the sound wave detection signal sent by the mobile terminal, the first sending module sends The demodulated sound wave detection signal is sent to the encryption key;

an echo matching module, configured to judge the echo from the demodulated sound wave detection signal of the modulating module after the second receiving module receives the echo of the demodulated sound wave detection signal returned by the second sending module Whether it matches, if it matches, the first sending module sends the matched acoustic wave detection signal to the encryption key;

The first extraction module is configured to extract the acoustic features and/or language features in the sound wave detection signal received by the second receiving module and controlled by the sound;

A second extraction module, configured to extract the acoustic features and/or language features in the echo of the demodulated acoustic wave detection signal received by the second receiving module;

A pattern matching module, configured to perform pattern matching on the acoustic features and/or language features extracted by the first extraction module or the second extraction module, and transmit transaction data if the matching is successful.

Another object of the embodiments of the invention is to provide an authentication system for a cryptographic key, the system comprising the above-mentioned cryptographic key and the above-mentioned mobile terminal.

In the encryption key authentication method and system of the present invention, the mobile terminal sends sound wave detection signals to the encryption key at least twice, and matches the sound wave detection signal returned by the encryption key for the last time, and transmits transaction data if the matching is successful. Compared with the existing method of authenticating only one audio data sent by a mobile terminal, the method and system can transmit audio data more safely and reliably, and ensure the security of subsequent transaction data.

Description of drawings

Fig. 1 is the flowchart of the authentication method of the cryptographic key provided by the present invention;

Fig. 2 is a flow chart of interaction between the mobile terminal and the encryption key in the present invention;

Fig. 3 is another interactive flowchart between the mobile terminal and the encryption key in the present invention;

Fig. 4 is another interactive flowchart between the mobile terminal and the encryption key in the present invention;

Fig. 5 is the structural diagram of the authentication system of the cryptographic key provided by the present invention;

Fig. 6 is a structural diagram of the authentication unit in Fig. 5;

Fig. 7 is another structural diagram of the authentication unit in Fig. 5;

FIG. 8 is another structural diagram of the authentication unit in FIG. 5 .

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

Aiming at the problems existing in the prior art, in the present invention, the mobile terminal sends the sound wave detection signal to the password key at least twice, and matches the sound wave detection signal returned by the password key for the last time, and if the matching is successful, the transaction data (such as: account number , head of household, amount, etc.). The encryption key in the present invention includes a wired encryption key and a wireless encryption key.

Fig. 1 shows the flow process of the authentication method of the encryption key provided by the present invention, comprises the following steps:

Step S1: Before transmitting the transaction data, control the sound wave detection signal to transmit and receive at least two times between the mobile terminal and the encryption key, and when the mobile terminal sends the sound wave detection signal to the encryption key this time, it receives the return signal from the encryption key When the sound wave detection signal is used, the mobile terminal is controlled to send the next sound wave detection signal to the password key.

Step S2: When the control mobile terminal receives the sound wave detection signal for the last time, control the mobile terminal to match the sound wave detection signal received last time, and if the matching is successful, control the mobile terminal to transmit transaction data to the encryption key.

The above-mentioned method is described in detail in three embodiments below:

In the authentication method of the encryption key provided in the first embodiment of the present invention, the mobile terminal sends the acoustic wave detection signal to the encryption key three times, as shown in FIG. 2 , at this time, step S1 further includes:

Step S101: the mobile terminal sends a sound wave detection signal to the password key;

Step S102: The cipher key receives the sound wave detection signal sent by the mobile terminal, and uses a preset modulation method to modulate the received sound wave detection signal to the selected sound frequency point. The modulation method can be the existing Frequency Shift Keying (Frequency -shift Keying (FSK) method, amplitude shift keying (Amplitude ShiftKeying, ASK) method, phase-shift keying (Phase-shift Keying, PSK) method, phase quadrature amplitude modulation (Quadrature Amplitude Modulation, QAM) method, quadrature frequency Any of Orthogonal Frequency Division Multiplexing (OFDM), etc.;

Step S103: the encrypted key sends the modulated sound wave detection signal to the mobile terminal;

Step S104: The mobile terminal receives the modulated sound wave detection signal sent by the encryption key, and demodulates the received sound wave detection signal;

Step S105: If the sound wave detection signal demodulated by the mobile terminal is the same as the sound wave detection signal sent by the mobile terminal, then the mobile terminal sends the demodulated sound wave detection signal to the encryption key;

Step S106: The cipher key demodulates the received modulated sound wave detection signal, and then returns the echo of the demodulated sound wave detection signal to the mobile terminal. The echo can be the demodulated sound wave detection signal itself, or the demodulated sound wave The encoded signal of the detection signal, and the encoding method of the demodulated acoustic detection signal can be CLC check, HASH encoding, BCH encoding, etc.;

Step S107: The mobile terminal receives the echo, and judges whether the echo matches the previously sent and demodulated sound wave detection signal, that is, judges whether the echo is consistent with the previously sent and demodulated sound wave detection signal;

Step S108: If the mobile terminal judges that the echo matches the previously sent and demodulated sound wave detection signal, then send the matched sound wave detection signal to the encryption key;

Step S109: the cipher key receives the matched sound wave detection signal sent by the mobile terminal, and performs dual-band sound control on the matched sound wave detection signal;

Step S110: the password key sends the sound wave detection signal after sound control to the mobile terminal.

Wherein, in step S109, if the sound wave detection signal is a dual-frequency signal, the following three methods can be used to realize the sound control of the dual-frequency band: 1. The two-way sound wave detection signal is superimposed into one road sound wave detection signal, which can increase The throughput of information can increase the communication speed; 2. The audio data carried by the sound wave detection signal is modulated onto one signal, and the check code is modulated onto another signal. The check code represents the signal carrying audio data 3. Modulate the audio data carried by the sound wave detection signal on one signal, and modulate the synchronization information on the other signal. The synchronization information represents the frequency band of the signal carrying the audio data. The latter two methods can ensure the security of audio data transmission.

In the cryptographic key authentication method provided in the first embodiment of the present invention, step S2 further includes:

Step S201: the mobile terminal extracts the acoustic features and/or language features in the received sound wave detection signal after sound control;

Step S202: Perform pattern matching on the extracted acoustic features and/or language features, and transmit transaction data if the matching is successful. The pattern matching algorithm can be a probability statistics algorithm, a dynamic time warping algorithm, a vector quantization algorithm, a hidden Markov model algorithm, an artificial neural network algorithm, etc., which are well known in the field of voiceprint recognition and will not be listed here.

In the encryption key authentication method provided in the second embodiment of the present invention, the mobile terminal sends the acoustic wave detection signal to the encryption key twice, as shown in FIG. 3 , at this time, step S1 further includes:

Step S111: the mobile terminal sends a sound wave detection signal to the password key;

Step S112: The cipher key receives the sound wave detection signal sent by the mobile terminal, and uses a preset modulation method to modulate the received sound wave detection signal to a selected sound frequency point. The modulation method is as described above and will not be repeated here;

Step S113: the encrypted key sends the modulated sound wave detection signal to the mobile terminal;

Step S114: The mobile terminal demodulates the received acoustic wave detection signal;

Step S115: If the sound wave detection signal demodulated by the mobile terminal is the same as the sound wave detection signal sent by the mobile terminal, then the mobile terminal sends the demodulated sound wave detection signal to the encryption key;

Step S116: After receiving the demodulated sound wave detection signal, the cipher key returns the echo of the demodulated sound wave detection signal to the mobile terminal. The echo can be the demodulated sound wave detection signal itself or the demodulated sound wave detection signal. The encoded acoustic wave detection signal, and the encoding method of the demodulated acoustic wave detection signal may be CLC check, HASH encoding, BCH encoding, etc.

In the cryptographic key authentication method provided in the second embodiment of the present invention, step S2 further includes:

Step S203: the mobile terminal extracts the acoustic features and/or language features in the echoes of the received and demodulated acoustic wave detection signals;

Step S204: Perform pattern matching on the extracted acoustic features and/or language features, and transmit transaction data if the matching is successful. The pattern matching algorithm is as described above and will not be repeated here.

In the authentication method of the encryption key provided in the third embodiment of the present invention, the mobile terminal also sends the sound wave detection signal to the encryption key twice, as shown in FIG. 4 , at this time, step S1 further includes:

Step S117: the mobile terminal sends a sound wave detection signal to the password key;

Step S118: The encryption key receives the sound wave detection signal sent by the mobile terminal, and uses a preset modulation method to modulate the received sound wave detection signal to a selected sound frequency point. The modulation method is as described above and will not be described here;

Step S119: the encrypted key sends the modulated sound wave detection signal to the mobile terminal;

Step S120: the mobile terminal receives the modulated sound wave detection signal sent by the encryption key, and demodulates the modulated sound wave detection signal;

Step S121: If the sound wave detection signal demodulated by the mobile terminal is the same as the sound wave detection signal sent by the mobile terminal, then the mobile terminal sends the demodulated sound wave detection signal to the encryption key;

Step S122: the encrypted key performs dual-band sound control on the demodulated sound wave detection signal sent by the mobile terminal;

Step S123: the password key sends the sound wave detection signal after sound control to the mobile terminal.

In the cryptographic key authentication method provided in the third embodiment of the present invention, the specific steps of step S2 are the same as the cryptographic key authentication method provided in the first embodiment of the present invention, and will not be repeated here.

The present invention also provides an authentication system for a cryptographic key. FIG. 5 shows the structure of the authentication system. For ease of description, only the parts related to the present invention are shown.

Specifically, the cryptographic key authentication system provided by the present invention includes: an authentication unit 1, used to control the sound wave detection signal to perform at least two sending and receiving transmissions between the mobile terminal and the cryptographic key before transmitting transaction data, and when the mobile terminal is in After sending the sound wave detection signal to the password key this time, when receiving the sound wave detection signal returned by the password key, control the mobile terminal to send the next sound wave detection signal to the password key; When the sound wave detection signal is received once, the mobile terminal is controlled to match the sound wave detection signal received last time, and if the matching is successful, the mobile terminal is controlled to transmit transaction data to the encrypted key.

The above-mentioned system is described in detail in three embodiments below:

In the authentication system of the encryption key provided in the first embodiment of the present invention, the mobile terminal sends the sound wave detection signal to the encryption key three times, as shown in FIG. 6 , at this time, the authentication unit 1 includes: Module 101 is used to send the sound wave detection signal to the code key; the first receiving module 102 placed on the code key is used to receive the sound wave detection signal sent by the first sending module 101; the modulation module 103 placed on the code key is used to adopt Preset modulation mode, modulate the received sound wave detection signal to the selected audio frequency point, the modulation mode is as described above, and will not be described in detail here; the second sending module 104 placed in the password key is used to transfer the modulation module 103 The modulated sound wave detection signal is sent to the mobile terminal; the second receiving module 105 placed in the mobile terminal is used to receive the modulated sound wave detection signal sent by the encryption key; the demodulation module 106 placed in the mobile terminal is used for The sound wave detection signal received by the second receiving module 105 is demodulated, if the sound wave detection signal after demodulation is the same as the sound wave detection signal sent by the mobile terminal, then the first sending module 101 sends the demodulated sound wave detection signal to The first receiving module 102; the echo matching module 108 placed in the mobile terminal, used to judge the echo and the modulation module after the second receiving module 105 receives the echo of the demodulated sound wave detection signal returned by the second sending module 104 103 Whether the demodulated sound wave detection signal matches, if it matches, the first sending module 101 sends the matched sound wave detection signal to the first receiving module 102; The matched sound wave detection signal received by a receiving module 102 performs dual-band sound control, and sends the sound wave detection signal after the sound control to the second receiving module 105 through the second sending module 104. The specific process is as described above, I won't go into details here.

Wherein, when the echo is the demodulated sound wave detection signal itself, the second sending module 104 directly sends the demodulated sound wave detection signal received by the first receiving module 102 to the second receiving module 105; When the final sound wave detection signal is an encoded signal, the authentication unit 1 may also include: an encoding module 107 placed in the encryption key, for encoding the demodulated sound wave detection signal received by the first receiving module 102, The second sending module 104 sends the demodulated sound wave detection signal encoded by the encoding module 107 to the second receiving module 105 . Wherein, the encoding mode of the encoding module 107 for the demodulated sound wave detection signal may be CLC check, HASH encoding, BCH encoding and the like.

In the cryptographic key authentication system provided in the first embodiment of the present invention, the transaction control unit 2 further includes: a first extraction module, used to extract the acoustic wave detection signal received by the second receiving module 105 and controlled by the sound; Features and/or language features; a pattern matching module, configured to perform pattern matching on the acoustic features and/or language features extracted by the first extraction module, and transmit transaction data if the matching is successful. The pattern matching algorithm is as described above and will not be repeated here.

Further, in the cryptographic key authentication system provided in the first embodiment of the present invention, the mobile terminal may include: a first low-noise amplifier connected to the second receiving module 105 and with an automatic gain control function for detecting the second receiving module 105 The strength of the acoustic detection signal received by the module 105, and adjust the gain size of the second receiving module 105 according to the detection result, for example, if the detected strength is greater than or equal to a preset strength value, then reduce the gain of the second receiving module 105 Gain; and a first noise filter connected to the first low-noise amplifier, for filtering the acoustic detection signal output by the first low-noise amplifier, to filter out unnecessary frequency signals therein. Similarly, the encryption key may include: a second low noise amplifier connected to the first receiving module 102 and with an automatic gain control function, used to detect the strength of the acoustic detection signal received by the first receiving module 102, and adjust the signal according to the detection result. The gain of the first receiving module 102, for example, if the detected intensity is greater than or equal to a preset intensity value, then reduce the gain of the first receiving module 102; and the second noise filter connected to the second low noise amplifier, It is used for performing filtering processing on the sound wave detection signal output by the second low noise amplifier, so as to filter out unnecessary frequency signals therein.

In the cryptographic key authentication system provided by the second embodiment of the present invention, the mobile terminal sends the acoustic wave detection signal to the cryptographic key twice, as shown in FIG. 7 , which is different from that shown in FIG. The sound control module 109 and the echo matching module 108 placed in the password key, other structures and functions are as described above, and will not be repeated here.

In the cryptographic key authentication system provided in the second embodiment of the present invention, the transaction control unit 2 further includes: a second extraction module, used to extract the echo of the demodulated sound wave detection signal received by the second receiving module 105 The acoustic features and/or language features of the second extraction module; the pattern matching module is used to perform pattern matching on the acoustic features and/or language features extracted by the second extraction module, and if the matching is successful, the transaction data is transmitted.

Similarly, in the cryptographic key authentication system provided in the second embodiment of the present invention, the mobile terminal may include the above-mentioned first low-noise amplifier and the first noise filter, and the cryptographic key may include the above-mentioned second low-noise amplifier. noise amplifier and second noise filter.

In the cryptographic key authentication system provided by the third embodiment of the present invention, the mobile terminal sends the acoustic detection signal to the cryptographic key twice, as shown in FIG. 8 , which is different from that shown in FIG. The other structures of the echo matching module 108 placed in the mobile terminal and the encoding module 107 placed in the cipher key are the same as those shown in FIG. 6 . Among them, the first sending module 101 is used to send the sound wave detection signal to the encryption key; the first receiving module 102 is used to receive the sound wave detection signal sent by the first sending module 101; The sound wave detection signal is modulated to the selected sound frequency point, the modulation method is as described above, and will not be described in detail here; the second sending module 104 is used to send the sound wave detection signal modulated by the modulation module 103 to the mobile terminal; the second The receiving module 105 is used to receive the modulated sound wave detection signal sent by the cipher key; the demodulation module 106 is used to demodulate the modulated sound wave detection signal received by the second receiving module 105, if the demodulated sound wave detection signal The signal is the same as the sound wave detection signal sent by the mobile terminal, then the first sending module 101 sends the demodulated sound wave detection signal to the first receiving module 102; the sound control module 109 is used to demodulate the first receiving module 102 received The final sound wave detection signal is subjected to dual-band sound control, and the sound wave detection signal after sound control is sent to the second receiving module 105 through the second sending module 104. The specific process is as described above and will not be repeated here.

Similarly, in the cryptographic key authentication system provided in the third embodiment of the present invention, the mobile terminal may include the first low noise amplifier and the first noise filter as described above, and the cryptographic key may include the second low noise amplifier as described above. noise amplifier and second noise filter.

The embodiment of the invention also provides a cryptographic key. In one embodiment of the present invention, the mobile terminal sends the sound wave detection signal to the encryption key three times, and the key key specifically includes the first receiving module 102, modulation module 103, second sending module 104, and sound control module 109 as described above.

Wherein, when the echo is the demodulated sound wave detection signal itself, the second sending module 104 directly sends the demodulated sound wave detection signal received by the first receiving module 102 to the mobile terminal; When the detected signal is an encoded signal, the encryption key may further include the encoding module 107 as described above.

In an embodiment of the present invention, the encryption key may further include the above-mentioned second low noise amplifier and second noise filter.

Corresponding to the key provided by one embodiment of the present invention, the embodiment of the present invention also provides a mobile terminal. The mobile terminal specifically includes: a first sending module 101, a second receiving module 105, a demodulation module 106, an echo matching module 108, a first extraction module, and a pattern matching module.

Further, the mobile terminal may further include the first low noise amplifier and the first noise filter as described above.

In another embodiment of the present invention, the mobile terminal sends the acoustic wave detection signal to the encryption key twice, and the encryption key specifically includes the first receiving module 102, the modulating module 103, and the second sending module 104 as described above.

Wherein, when the echo is the demodulated sound wave detection signal itself, the second sending module 104 directly sends the demodulated sound wave detection signal received by the first receiving module 102 to the mobile terminal; When the detected signal is an encoded signal, the encryption key may further include the encoding module 107 as described above.

In another embodiment of the present invention, the encryption key may further include the second low noise amplifier and the second noise filter as described above.

Corresponding to the key provided in another embodiment of the present invention, the embodiment of the present invention also provides a mobile terminal. The mobile terminal specifically includes: a first sending module 101, a second receiving module 105, a demodulation module 106, a second extraction module, and a pattern matching module.

Further, the mobile terminal may further include the first low noise amplifier and the first noise filter as described above.

In yet another embodiment of the present invention, the mobile terminal sends the sound wave detection signal to the encryption key twice, and the key key specifically includes the first receiving module 102, the modulation module 103, the second sending module 104, and the sound control module as described above. 109.

In yet another embodiment of the present invention, the encryption key may further include the second low noise amplifier and the second noise filter as described above.

Corresponding to the key provided in another embodiment of the present invention, the embodiment of the present invention also provides a mobile terminal. The mobile terminal specifically includes: a first sending module 101, a second receiving module 105, a demodulation module 106, a first extraction module, and a pattern matching module.

Further, the mobile terminal may further include the first low noise amplifier and the first noise filter as described above.

In the encryption key authentication method and system of the present invention, the mobile terminal sends sound wave detection signals to the encryption key at least twice, and matches the sound wave detection signal returned by the encryption key for the last time, and transmits transaction data if the matching is successful. Compared with the existing method of authenticating only one audio data sent by a mobile terminal, the method and system can transmit audio data more safely and reliably, and ensure the security of subsequent transaction data. Furthermore, in an embodiment, the mobile terminal can adopt an echo matching method to judge the consistency between the emitted sound wave detection signal and its echo, so as to further ensure the safety of audio data transmission. In addition, the method and system can use voiceprint recognition to perform voiceprint recognition on the last sound wave detection signal received by the mobile terminal, so as to ensure the authenticity of the identity of the encryption key and further ensure the security of audio data transmission. Furthermore, in the mobile terminal and/or the cipher key, a low-noise amplifier with an automatic gain control function and a noise filter can be set, which can reduce the interference of distance factors or surrounding environmental factors on the transmitted audio data, and stabilize the audio data. transmission.

Those of ordinary skill in the art can understand that all or part of the steps in the methods of the above embodiments can be implemented by controlling related hardware through a program, and the program can be stored in a computer-readable storage medium, and the storage Media such as ROM/RAM, magnetic disk, optical disk, etc.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the protection of the present invention. within range.

Claims (7)

1. an authentication method of a cryptographic key, characterized in that the method comprises: Step S1: Before transmitting the transaction data, control the sound wave detection signal to be sent and received at least twice between the mobile terminal and the encryption key, and when the mobile terminal sends the sound wave detection signal to the encryption key this time, When receiving the sound wave detection signal returned by the encryption key, control the mobile terminal to send the next sound wave detection signal to the encryption key; Step S2: control the mobile terminal to receive the sound wave detection signal for the last time , controlling the mobile terminal to match the last received acoustic wave detection signal, and if the matching is successful, controlling the mobile terminal to transmit the transaction data to the cipher key; Step S1 includes: Step S101: the mobile terminal sends the sound wave detection signal to the encryption key; Step S102: the encryption key receives the sound wave detection signal sent by the mobile terminal, and uses a preset modulation method to modulate the sound wave detection signal to a selected sound frequency point; Step S103: the encrypted key sends the modulated sound wave detection signal to the mobile terminal; Step S104: the mobile terminal receives the modulated acoustic wave detection signal, and demodulates the modulated acoustic wave detection signal; Step S105: If the sound wave detection signal demodulated by the mobile terminal is the same as the sound wave detection signal sent by the mobile terminal, then the mobile terminal sends the demodulated sound wave detection signal to the encryption key; Step S106: The encryption key receives the demodulated sound wave detection signal, and then returns an echo of the demodulated sound wave detection signal to the mobile terminal; Step S107: the mobile terminal receives the echo, and judges whether the echo matches the previously sent and demodulated sound wave detection signal; Step S108: If the mobile terminal judges that the echo matches the previously sent and demodulated sound wave detection signal, then send the matched sound wave detection signal to the encryption key; Step S109: The cipher key receives the matched sound wave detection signal sent by the mobile terminal, and performs dual-band sound control on the matched sound wave detection signal; the dual-band sound control includes: converting the sound wave detection signal to The carried audio data is modulated onto one signal, and the check code is modulated onto another signal. The check code represents the start and end position of the signal carrying the audio data, or the audio data carried by the sound wave detection signal is modulated onto one signal on, modulate the synchronous information onto another signal, and the synchronous information represents the frequency band of the signal carrying the audio data; Step S110: the cipher key sends the sound wave detection signal after sound control to the mobile terminal; Alternatively, step S1 includes: Step S117: the mobile terminal sends a sound wave detection signal to the encryption key; Step S118: the cipher key receives the sound wave detection signal, and modulates the received sound wave detection signal to a selected sound frequency point by using a preset modulation method; Step S119: the encryption key sends the modulated sound wave detection signal to the mobile terminal; Step S120: the mobile terminal receives the modulated sound wave detection signal sent by the encryption key, and demodulates the modulated sound wave detection signal; Step S121: If the sound wave detection signal demodulated by the mobile terminal is the same as the sound wave detection signal sent by the mobile terminal, then the mobile terminal sends the demodulated sound wave detection signal to the encryption key; Step S122: the cipher key performs dual-band sound control on the demodulated sound wave detection signal sent by the mobile terminal; Step S123: the cipher key sends the sound wave detection signal after sound control to the mobile terminal; Alternatively, step S1 includes: Step S111: the mobile terminal sends a sound wave detection signal to the encryption key; Step S112: the cipher key receives the sound wave detection signal, and modulates the received sound wave detection signal to a selected sound frequency point by using a preset modulation method; Step S113: the encrypted key sends the modulated sound wave detection signal to the mobile terminal; Step S114: The mobile terminal demodulates the received acoustic wave detection signal; Step S115: If the sound wave detection signal demodulated by the mobile terminal is the same as the sound wave detection signal sent by the mobile terminal, then the mobile terminal sends the demodulated sound wave detection signal to the encryption key; Step S116: After receiving the demodulated sound wave detection signal, the encryption key returns an echo of the demodulated sound wave detection signal to the mobile terminal. 2. the authentication method of cryptographic key as claimed in claim 1, is characterized in that, described step S2 further comprises: Step S201: the mobile terminal extracts the acoustic features and/or language features in the received sound wave detection signal after sound control; Step S202: Perform pattern matching on the extracted acoustic features and/or language features, and transmit transaction data if the matching is successful. 3. the authentication method of cryptographic key as claimed in claim 1, is characterized in that, described step S2 further comprises: Step S203: the mobile terminal extracts the acoustic features and/or language features in the echoes of the received and demodulated acoustic wave detection signals; Step S204: Perform pattern matching on the extracted acoustic features and/or language features, and transmit transaction data if the matching is successful. 4. A cryptographic key, characterized in that, the cryptographic key comprises: The first receiving module is used to receive the sound wave detection signal sent by the mobile terminal; it is also used to receive the demodulated sound wave detection signal; A modulation module, configured to modulate the received sound wave detection signal to a selected sound frequency point by adopting a preset modulation method; The second sending module is used to send the sound wave detection signal modulated by the modulation module to the mobile terminal; it is also used for the first receiving module to receive the demodulated sound wave detection signal, and then return it to the mobile terminal The echo of the demodulated acoustic detection signal; The sound control module is configured to perform dual-band sound control on the matched sound wave detection signal received by the first receiving module and sent by the mobile terminal, and pass the sound control sound wave detection signal through the second The sending module sends it to the mobile terminal. The dual-band sound control includes: modulating the audio data carried by the sound wave detection signal to one signal, and modulating a check code to another signal. The start and end positions of the signal with audio data, or the audio data carried by the sound wave detection signal is modulated on one signal, and the synchronization information is modulated on the other signal. The synchronization information represents the frequency band of the signal carrying audio data. 5. A mobile terminal, characterized in that the mobile terminal comprises: The first sending module is used to send the sound wave detection signal to the encryption key; The second receiving module is used to receive the modulated sound wave detection signal sent by the encryption key; it is also used to receive the sound wave detection signal after the dual-band sound control sent by the second sending module; A demodulation module, configured to demodulate the sound wave detection signal received by the second receiving module, and if the demodulated sound wave detection signal is the same as the sound wave detection signal sent by the mobile terminal, the first sending module sends The demodulated sound wave detection signal is sent to the encryption key; an echo matching module, configured to judge the echo from the demodulated sound wave detection signal of the modulating module after the second receiving module receives the echo of the demodulated sound wave detection signal returned by the second sending module Whether it matches, if it matches, the first sending module sends the matched sound wave detection signal to the encryption key; The first extraction module is configured to extract the acoustic features and/or language features in the sound wave detection signal received by the second receiving module and controlled by the sound; A second extraction module, configured to extract the acoustic features and/or language features in the echo of the demodulated acoustic wave detection signal received by the second receiving module; A pattern matching module, configured to perform pattern matching on the acoustic features and/or language features extracted by the first extraction module or the second extraction module, and transmit transaction data if the matching is successful. 6. The mobile terminal according to claim 5, further comprising: Connecting the second receiving module and the first low noise amplifier with an automatic gain control function, used to detect the strength of the acoustic wave detection signal received by the second receiving module, and adjust the second receiving module according to the detection result. The gain of the receiving module; The first noise filter connected to the first low noise amplifier is used for filtering the acoustic wave detection signal output by the first low noise amplifier. 7. An authentication system for a cryptographic key, characterized in that the system comprises the cryptographic key as claimed in claim 4 and the mobile terminal as claimed in claim 5.