Abstract:
An encryption/decryption system and method are provided for a mobile phone configured to make a voice packet encryption/decryption during mobile communication. The mobile phone has a connecting interface for an external plug-in device. The encryption/decryption system inside the external plug-in device at least has a control unit, and a security chip. When a security communication mode is activated, the communication between users can be prevented from being disclosed. The present invention is to provide the encryption/decryption system and method for activating a security communication mode between two mobile users communicating in mobile communication, and for preventing communication packets from being disclosed.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation-in-part of U.S. patent application Ser. No. 13/035,739, filed on Feb. 25, 2011, which is incorporated herewith by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to an encryption/decryption system and method for a mobile phone, and more particularly to an encryption/decryption system and method for a mobile phone that is configured to make a voice packet encryption/decryption during mobile communication. 
         [0004]    2. The Prior Arts 
         [0005]    By the development of information industry, personal communication becomes more and more unsafe. According to recent articles, a Germany engineer announced that he has already cracked the encryption algorithm of mobile communication. The encryption technology is adapted for more than 21 years, and, among global 4.3 billion GSM mobile phones, eighty percent, i.e. 3.5 billion, GSM mobile phones use the security mechanism. 
         [0006]    When GSM is adapted as a standard in 1988, a 64-bit encryption technology is adapted too, which is a simple technology referring to today&#39;s technology level. Although the GSM association upgrades the encryption technology to 128-bit system in 2007, most telecommunication proprietors do not upgrade immediate due to insufficient funds. Meanwhile, due to continuous society development, how to define preventing a secret from being disclosed today becomes a comprehensive issue, such as business secret protection, and also, the contents of secret becomes diversified. 
       SUMMARY OF THE INVENTION 
       [0007]    Accordingly, it is an object of the present invention to provide an encryption/decryption system and method for activating a security communication mode between two mobile users communicating in mobile communication, and for preventing communication packets from being disclosed. 
         [0008]    Another objective of the present invention is to provide an encryption/decryption system and method applied in mobile communication without upgrading telecommunication equipment, and achieve secure mobile communication between two mobile users. 
         [0009]    The above and other objects of the present invention are achieved by an encryption/decryption system and method inside an external plug-in device, wherein the external plug-in device is connected with a mobile phone through a connecting interface of the mobile phone. The encryption/decryption system at least comprises a control unit electrically connected with the mobile phone through the connecting interface; a security chip which is controlled by the control unit, and is configured to convert a digital code into a digital encrypted package, wherein the digital code is transmitted from the mobile phone through the connecting interface to the control unit and then from the control unit to the security chip, and the security chip then transmits the digital encrypted package to the mobile phone through the connecting interface via the control unit, and/or, the security chip is configured to decrypt a digital encrypted package into a digital code, wherein the digital encrypted package is transmitted from the mobile phone through the connecting interface to the control unit and then from the control unit to the security chip, and the security chip then transmits the digital code to the mobile phone through the connecting interface via the control unit. 
         [0010]    Therefore, by realizing the aforementioned devices, the external plug-in device is connected to the mobile phone via the connecting interface. When the security communication mode is activated, the security chip of the encryption/decryption system inside the external plug-in device generates key and processes key exchanging. Then the encryption/decryption system of the external plug-in device is configured to encrypt/decrypt voice data for transmitting data to the calling party/called party. 
         [0011]    Further, the security chip comprises a key system being configured to generate key and process key exchange. The external plug-in device can also comprise a flash memory inside for a user to store data. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    The drawings disclose an illustrative embodiment of the present invention which serves to exemplify the various advantages and objects hereof, and are as follows: 
           [0013]      FIG. 1  is a block diagram illustrating an encryption/decryption system according to the present invention; 
           [0014]      FIG. 2  is a flowchart illustrating processes of an encryption/decryption method according to the encryption/decryption system of the present invention; 
           [0015]      FIG. 3  schematically illustrates a preferred embodiment of encryption/decryption system according to the present invention; 
           [0016]      FIG. 4  is a flowchart illustrating processes of an encryption/decryption method according to the embodiment in  FIG. 3  of the encryption/decryption system of the present invention; 
           [0017]      FIG. 5  is a block diagram illustrating system structure of a mobile phone; 
           [0018]      FIG. 6  shows an encryption flow of the encryption/decryption system and the mobile phone; 
           [0019]      FIG. 7  shows a decryption flow of the encryption/decryption system and the mobile phone; and 
           [0020]      FIG. 8  shows another embodiment of the encryption/decryption system for a mobile phone. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0021]      FIG. 1  is a block diagram illustrating an encryption/decryption system according to the present invention. As shown in  FIG. 1 , the encryption/decryption system  20  is inside an external plug-in device  12 , and a mobile phone  10  has a connecting interface  11  for the external plug-in device  12  being connected to the mobile phone  10 . The encryption/decryption system  20  at least comprises a control unit  21  electrically connected with the mobile phone  10  through the connecting interface  11 ;and, a security chip  22  which is controlled by the control unit  21 , and is configured to encrypt a digital code into a digital encrypted package, wherein the digital code is transmitted from the mobile phone  10  through the connecting interface  11  to the control unit  21  and then from the control unit  21  to the security chip  22 , and the security chip  22  then transmits the digital encrypted package to the mobile phone  10  through the connecting interface  11  via the control unit  21 , and/or, the security chip  22  is configured to decrypt a digital encrypted package into a digital code, wherein the digital encrypted package is transmitted from the mobile phone  10  through the connecting interface  11  to the control unit  21  and then from the control unit  21  to the security chip  22 , and the security chip  22  then transmits the digital code to the mobile phone  10  through the connecting interface  11  via the control unit  21 . 
         [0022]    The security chip  22  comprises a key system for generating keys and keys exchange. The present invention can further comprise a flash memory  23  inside the encryption/decryption system  20  of the external plug-in device  12  for a user to store data according to demands; therefore the control unit  21  can store digital data in the flash memory  23  according to user operation. 
         [0023]    When the security communication mode is activated, the security chip  22  of the encryption/decryption system  20  inside the external plug-in device  12  generates key and processes key exchanging. Then the encryption/decryption system  10  of the external plug-in device  12  is configured to encrypt/decrypt voice data for transmitting data to the calling party/called party. 
         [0024]      FIG. 2  is a flowchart illustrating processes of an encryption/decryption method according to the encryption/decryption system of the present invention. As shown in  FIG. 2 , at step  301 , the security chip  22  executes encryption/decryption process. The security chip  22  encrypts a digital code into a digital encrypted package, wherein the digital code is transmitted from the mobile phone  10  through the connecting interface  11  to the control unit  21  and then from the control unit  21  to the security chip  22 , and the security chip  22  then transmits the digital encrypted package to the control unit  21 , and/or, the security chip  22  decrypts a digital encrypted package into a digital code, wherein the digital encrypted package is transmitted from the mobile phone  10  through the connecting interface  11  to the control unit  21  and then from the control unit  21  to the security chip  22 , and the security chip  22  then transmits the digital code to the control unit  21 . 
         [0025]    In the second step  302 , the control unit transmits the digital encrypted package/the digital code. The control unit  21  transmits the digital encrypted package to the mobile phone  10  through the connecting interface  11 , and/or, the control unit  21  transmits the digital code to the mobile phone  10  through the connecting interface  11 . 
         [0026]    In step  303 , proceeding security communication. In the mobile security communication between two mobile phone  10 , the two mobile phone  10  generate random number, exchanges random number by PKI, and the security chip  22  of the encryption/decryption system  20  inside the plug-in the external plug-in device  12  proceeds encryption/decryption processes. 
         [0027]      FIG. 3  schematically illustrates a preferred embodiment of encryption/decryption system according to the present invention. As shown in  FIG. 4 , when a user in calling party/called party side  3  and a user in called party/calling party side  4  use the encryption/decryption system  20  of the present invention, the external plug-in device  12  is connected to the mobile phone  10  via the connecting interface  11 . By activating a security communication mode, the security chip  22  of the encryption/decryption system  20  inside the external plug-in device  12  is configured to generate keys and proceed keys exchange, and then the security chip  22  of the encryption/decryption system  20  inside the external plug-in device  12  is configured to encrypt/decrypt voice data for transmitting the data to the calling party/called party side  3  and the called party/calling party side  4 . 
         [0028]      FIG. 4  is a flowchart illustrating processes of an encryption/decryption method according to the embodiment in  FIG. 3  of the encryption/decryption system of the present invention. As shown in  FIG. 4 , at step  401 , in calling party/called party side  3  and in called party/calling party side  4 , the security chip  22  executes encryption/decryption process. In calling party/called party side  3  and/or in called party/calling party side  4 , the security chip  22  encrypts a digital code into a digital encrypted package, wherein the digital code is transmitted from the mobile phone  10  through the connecting interface  11  to the control unit  21  and then from the control unit  21  to the security chip  22 , and the security chip  22  then transmits the digital encrypted package to the control unit  21 , and, the security chip  22  decrypts a digital encrypted package into a digital code, wherein the digital encrypted package is transmitted from the mobile phone  10  in the called party/calling party side  4  and/or in the calling party/called party side  3 . In called party/calling party side  4  and/or in the calling party/called party side  3 , the security chip  22  encrypts a digital code into a digital encrypted package, wherein the digital code is transmitted from the mobile phone  10  through the connecting interface  11  to the control unit  21  and then from the control unit  21  to the security chip  22 , and the security chip  22  then transmits the digital encrypted package to the control unit  21 , and, the security chip  22  decrypts a digital encrypted package into a digital code, wherein the digital encrypted package is transmitted from the mobile phone  10  in the calling party/called party side  3  and/or in the called party/calling party side  4 . 
         [0029]    In the second step  402 , the control unit  21  transmits the digital encrypted package/the digital code. In the calling party/called party side  3  and/or in the called party/calling party side  4 , the control unit  21  transmits the digital encrypted package to the mobile phone  10  through the connecting interface  11 , and/or, the control unit  21  transmits the digital code to the mobile phone  10  through the connecting interface  11 . 
         [0030]    In step  403 , proceeding security communication. In the mobile security communication between two mobile phone  10  in the calling party/called party side  3  and/or in the called party/calling party side  4 , the two mobile phone  10  generate random number, exchanges random number by PKI, and the security chip  22  of the encryption/decryption system  20  inside the plug-in the external plug-in device  12  proceeds encryption/decryption processes. 
         [0031]      FIG. 5  is a block diagram illustrating system structure of a mobile phone. As shown in  FIG. 5 , the mobile phone  10  comprises an antenna  31 , a RF Called party/Transmitter module  32 , a baseband signal processing  33 , a voice processing unit  34 , a Multimedia speaker  35 , an accessory  36 , and a microphone  37 . When the mobile phone  10  receives data, an antenna  31  transmits the received signal to a RF Called party/Transmitter module  32 . The RF Called party/Transmitter module  32  proceeds the aforementioned signal by the baseband signal processing  33 , and then transmits the result to a voice processing unit  34  for decoding. Finally the voice is transmitted to the called party by a Multimedia speaker  35 . The mobile phone  10  has a connecting interface  11 , and the user can freely select an accessory  36  for installing the external plug-in device  12  on the mobile phone  10 . During transmission, the calling party transmits the voice via the microphone  37  to the voice processing unit  34  for being coded, and then the signal is transmitted to the baseband signal process  33 . Then the converted signal is transmitted to the RF Called party/Transmitter module  32  for being transmitted by the antenna  31 . 
         [0032]      FIG. 6  shows an encryption flow of the encryption/decryption system and the mobile phone. In calling party/called party side and/or in called party/calling party side, the calling party installs the external plug-in device  12  on the mobile phone  10  via the connecting interface  11  of the accessories  36 . When the calling party and the called party activate the security communication mode, the microphone  37  collects the calling party&#39;s voice and the voice processing unit  34  codes the voice data for being transmitted to the baseband signal processing  33 . Then the coded information is transmitted to the external plug-in device  12 , and the security chip  22  of the encryption/decryption system  20  inside the external plug-in device  12  then transmits the voice into a digital encrypted package. The digital encrypted package is then transmitted to the baseband signal processing  33  and transmitted to the RF Called party/Transmitter module  32  for being transmitted via the antenna  31 . 
         [0033]      FIG. 7  shows a decryption flow of the encryption/decryption system and the mobile phone. The called party installs the external plug-in device  12  on the mobile phone  10  via the connecting interface  11  of the accessories  36 . When the antenna  31  receives signal and transmits the signal to the RF transceiver  32 , the baseband signal processing  33  is configured to determine whether the phone call is a security encrypted phone call. Once the phone call is not a security encrypted phone call, the received signal is then decoded by the voice processing unit  34  and the Multimedia speaker  35  plays the voice to the called party. Once the phone call is ensured to be a security encrypted phone call, the baseband signal processing  33  then transmits the digital encrypted package to the external plug-in device  20  for decryption. Then the decrypted coding information is transmitted to the voice processing unit  34  for being decoded and the Multimedia speaker  35  plays the voice to the called party. By the aforementioned embodiment, the security communication between the calling party and the called party is ensured. 
         [0034]      FIG. 8  shows another embodiment of the encryption/decryption system for a mobile phone. To save space and well arranging wires, the control unit  21  and the security chip  22  can be integrated as a multi-function chip  24 . Therefore the aforementioned effects are also ensured as well as the space is saved and the manufacturing cost and malfunction rate are reduced. 
         [0035]    Comparing with the conventional technologies, the present invention has advantages as follows. 
         [0036]    1. The user can achieve security communication without waiting the Telecom operators to upgrade instruments. 
         [0037]    2. The present invention is easy to operate. The user only needs to install the external plug-in device on the mobile phone and follow simple operation steps without additional training. 
         [0038]    3. The present invention can be applied widely for the mobile phones with connecting device in the market. 
         [0039]    Although the present invention has been described with reference to the preferred embodiments thereof, it is apparent to those skilled in the art that a variety of modifications and changes may be made without departing from the scope of the present invention which is intended to be defined by the appended claims.