Abstract:
A calibration system for induction keys includes a signal source and a computing device. The signal source is configured to generate a low frequency (LF) signal and a magnetic field signal at intervals. The computing device is configured to receive the magnetic field signal transmitted by an induction key when the induction key senses the LF signal. The computing device is configured to obtain a magnetic field strength from the magnetic field signal, and then comparing the magnetic field strength with a pre-stored standard strength of the magnetic field to achieve an offset. The computing device sends the offset value to the induction key and enables the induction key to get a calibrated strength value of the magnetic field according to the offset value. This disclosure further provided an induction key and a calibration method.

Description:
FIELD 
       [0001]    The subject matter herein generally relates to a calibration system and a calibration method for induction keys. 
       BACKGROUND 
       [0002]    The use of passive keyless entry (PKE) systems in automobiles has increased significantly recently. The PKE systems have increased the convenience of entering an automobile, especially when the vehicle operator&#39;s hands are full. They also are more secure than prior key-based security systems. A PKE system enables a driver to lock/unlock an automobile using an induction key. The induction key can sense and identify a low frequency (LF) signal transmitted by the automobile, and use an ultra high frequency (UHF) signal emitter to lock/unlock the automobile. The accuracy and stability of sensing the LF signal by the induction key is important. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0003]    Implementations of the present technology will now be described, by way of example only, with reference to the attached figures. 
           [0004]      FIG. 1  is a block diagram of one embodiment of a calibration system for induction keys. 
           [0005]      FIGS. 2 and 3  illustrate a flow chart of processing the calibration system in  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION 
       [0006]    It will be appreciated that for simplicity and clarity of illustration, where appropriate, reference numerals have been repeated among the different figures to indicate corresponding or analogous elements. In addition, numerous specific details are set forth in order to provide a thorough understanding of the embodiments described herein. However, it will be understood by those of ordinary skill in the art that the embodiments described herein can be practiced without these specific details. In other instances, methods, procedures and components have not been described in detail so as not to obscure the related relevant feature being described. Also, the description is not to be considered as limiting the scope of the embodiments described herein. The drawings are not necessarily to scale and the proportions of certain parts may be exaggerated to better illustrate details and features of the present disclosure. 
         [0007]    A definition that applies throughout this disclosure will now be presented. 
         [0008]    The term “comprising” when utilized, means “including, but not necessarily limited to”; it specifically indicates open-ended inclusion or membership in the so-described combination, group, series and the like. 
         [0009]    The present disclosure relates to a calibration system, a calibration method using the calibration system, and an automobile. 
         [0010]      FIG. 1  illustrates a calibration system  100  used to calibrate an induction key  300 . The calibration system  100  can include a signal source  10  and a computing device  20 . The signal source  10  can be adapted for generating and transmitting low frequency (LF) signal and magnetic field to the induction key  300 . The computing device  20  can wirelessly communicate with the induction key  300 . 
         [0011]    In at least one embodiment, the induction key  300  can include a sensing module  304 , a first communication module  306 , a processing module  308 , and a storage unit  309  electrically connected in turn. The sensing module  304  can be adapted for sensing the LF signal and the magnetic field signal, and starting the induction key  300 . The first communication module  306  can wirelessly communicate with the computing device  20 , such that the magnetic field signal sensed by the induction key  300  can be sent to the computing device  20 . In at least one embodiment, the first communication module  306  can be an ultra high frequency (UHF) signal emitter/receiver. The processing module  308  can provide an operational function, for example, the processing module  308  can calculate a magnetic field strength. The storage unit  309  can provide a storage function, for example, the storage unit  309  can used to store an offset value. 
         [0012]    The induction key  300  can further include a first codec module  305  electrically connected to the first communication module  306 . The first codec module  305  can set up an identification program to validate an identification code received by the first communication module  306 . If the identification code is adapted to the identification program, the induction key  300  can match with the device which emit the identification code for receiving signal from the device. If not, the induction key  300  would not match with the device. 
         [0013]    In at least one embodiment, the signal source  10  can include a signal generator  13 , and helmholtz coils  15  connected to the signal generator  13 . The signal generator  13  can be used to generate a LF signal and output corresponding voltage to the helmholtz coils  15 . The helmholtz coils  15  can generate an uniform, standard magnetic field. In at least one embodiment, the induction key  300  can be positioned near a center of a shaft of the helmholtz coils  15 . The LF signal and the magnetic field can be sensed by the induction key  300  to start the induction key  300 . 
         [0014]    The computing device  20  can be a computer, a mobile phone or other electronic devices. The computing device  20  can include a second communicating module  202 , a computing module  204 , and a storage module  206  electrically connected in turn. In at least one embodiment, the storage module  206  can store a standard magnetic field strength generated by the signal source  10 . The second communicating module  202  can wirelessly communicate with the first communicating module  304  of the induction key  300 , and configured to receive the magnetic field signal sent by the induction key  30 . In at least one embodiment, the second communication module  202  can be an UHF signal emitter/receiver. The computing module  204  can be adapted to obtain the magnetic field strength, and compare the magnetic field strength with the standard magnetic field strength, thus an offset value can be obtained. If the offset is not equal to zero, the offset value signal can be sent to the induction key  300  by the second communication module  202 , and the offset value can be stored in the induction key  300 . When the signal source  10  transmits the LF signal and the magnetic field again, the processing module  308  can obtain a magnetic field strength after calibration based on the magnetic field strength plus the stored offset value. The magnetic field strength signal can be sent to the computing device  20 , and the computing device  20  can compare the magnetic field strength to the standard magnetic field strength. The signal generator  10  can generate the magnetic field repeatedly until the magnetic field strength after calibration is consistent with the standard magnetic field strength. 
         [0015]    The computing device  20  can further include a second codec module  208  electrically connected to the first communicating module  304 . The second codec module  208  can be similar to the first codec module  305 . After the second communication module  202  received a first identification code transmitted by the first communication module  304 , the second codec module  208  can identify the first identification code. If the second codec module  208  can identify the first identification code, the computing device  20  can match with the induction key  300  to receive the magnetic filed signal transmitted by the induction key  300 , and the computing device  20  can send a second identification code to the induction key  300 . 
         [0016]    Referring to  FIG. 2  and  FIG. 3 , a flowchart is presented in accordance with an example embodiment of processing the calibration system in  FIG. 1 . The example method is provided by way of example, as there are a variety of ways to carry out the method. Each block shown in  FIG. 2  and  FIG. 3  represent one or more processes, methods or subroutines, carried out in the example method. Additionally, the illustrated order of blocks is by example only and the order of the blocks can change according to the present disclosure. The example method can begin from the block  101 . 
         [0017]    At block  101 , the signal generator  13  can emit the LF signal, and the helmholtz coils  15  connected to the signal generator  13  can emit the magnetic field. 
         [0018]    At block  102 , the sensing module  304  of the induction key  300  can sense the LF signal and start the induction key  300 , and the first communication module  306  can send out the magnetic field signal and the first identification code. 
         [0019]    At block  103 , the second communication module  202  of the computing device  20  can receive the first identification code, and the second codec module  208  can identify the first identification code. If the first identification code is correct, the computing device  20  can match with the induction key  300 . If the first identification code is incorrect, the process can be finished. 
         [0020]    After the computing device  20  is paired with the induction key  300 , the computing device  20  can receive the magnetic signal sent by the first communication module  306 . The computing device  204  can process the magnetic signal to obtain the magnetic field strength, and compare the magnetic field strength with the standard magnetic field strength obtained from the storage module  206 . 
         [0021]    At block  105 , if the magnetic field strength is consistent with the standard magnetic field strength, the process can be finished. If not, the computing module  204  can calculate an offset value Y 1  between the magnetic field strength and the standard magnetic field strength. The second communication module  202  can send out the offset value and the second identification code. 
         [0022]    At block  106 , the first communication module  304  can receive the second identification code sent by the second communication module  202 , and the first codec module  305  can identify the second identification code. 
         [0023]    At block  107 , if the induction key  300  can recognize the second identification code, the first communication module  304  of the induction key  300  can receive the offset value Y 1  sent by the computing device  20 , and store the offset value Y 1  to the storage unit  309 . If not, the process can be finished. 
         [0024]    At block  108 , the signal generator  13  can transmit the LF signal again, and the helmholtz coils  15  connected to the signal generator  13  can emit the magnetic field at the same time. 
         [0025]    At block  109 , the sensing module  304  of the induction key  300  can sense and send the LF signal and the magnetic field to the processing module  308 . The processing module  308  can obtain the magnetic field strength, and obtain a magnetic field strength X 1  after calibration based on the magnetic field strength value plus the offset value Y 1 . The first communication module  306  can send out the magnetic field signal and the first identification code. 
         [0026]    After that, the process at block  103  to block  109  can be repeated. The computing device  20  can identify the first identification code sent by the induction key  300  and receive the magnetic field signal after calibration. The computing module  204  can obtain the magnetic field strength X 1 , and compare the magnetic field strength X 1  with the standard magnetic field strength. If the magnetic field strength value X 1  is consistent with the standard magnetic field strength, the process can be finished. If not, the computing module  204  can calculate an offset value Y 2  between the magnetic field strength X 1  and the standard magnetic field strength. The second communication module  202  can send out the offset value Y 2  and the second identification code. The induction key  300  can identify the second identification code, and the first communication module  306  can receive and store the offset value Y 2  to the storage unit. At this time, the offset value Y 2  can replace the offset value Y 1 , and the signal generator  10  can generate the LF signal and magnetic field repeatedly, until the magnetic field Xn can be consistent with the standard magnetic field, and the process can be finished. 
         [0027]    In the calibration system and the calibration method of this disclosure, the signal generator  10  can generate the magnetic field, and the induction key  300  can sense and send the magnetic filed signal to the computing device  20 , such that the computing device  20  can compare the magnetic filed strength to the standard magnetic filed strength, and obtain an offset value. When the signal generator  10  generates the magnetic field again, the calibration system can enable the induction key  300  to obtain a calibrated magnetic filed strength based on the offset value. Therefore, the accuracy and stability of sensing the signal by the induction key  300  can be improved. 
         [0028]    In other embodiments, the first codec module  305  and the second codec module  208  can be omitted, and the induction key  300  can exchange information with the computing device through the first communication module  306  and the second communication module  202   
         [0029]    The calibration system  100  can calibrate two or more induction keys  300  at the same time. 
         [0030]    The embodiments shown and described above are only examples. Many details are often found in the art such as the other features of an induction key, a calibration system, and a calibration method. Therefore, many such details are neither shown nor described. Even though numerous characteristics and advantages of the present technology have been set forth in the foregoing description, together with details of the structure and function of the present disclosure, the disclosure is illustrative only, and changes may be made in the detail, especially in matters of shape, size and arrangement of the parts within the principles of the present disclosure up to, and including, the full extent established by the broad general meaning of the terms used in the claims. It will therefore be appreciated that the embodiments described above may be modified within the scope of the claims.