JP2013014926A - Keyless entry system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a keyless entry system having enhanced reliability of security without complicated structure.SOLUTION: A keyless entry system 1 comprises: a portable electronic key 3 having an operation switch and a transmitting element which emits a signal wave S composed of visible rays including superimposed command data in response to the operation of the operation switch; and a vehicle 2 which has a receiving element for receiving the signal wave S from the emitting element and allows a door to be locked or unlocked when the receiving element receives the signal wave S including the superimposed command data.

Description

  The present invention relates to a keyless entry system for a vehicle.

  2. Description of the Related Art Today, a keyless entry system in which a command for locking and unlocking a vehicle door is performed using a wireless signal of a portable electronic key is widely used. This keyless entry system can be locked and unlocked with only a few operations of the operation switch of the portable electronic key, so it is very convenient when you have a lot of luggage and your hands are blocked. Is. The keyless entry system generally uses radio waves and infrared rays as radio signals, and convenient functions and security using them have been developed so far.

  A radio wave type keyless entry system that uses radio waves for radio signals is not easily affected by obstacles because the radio wave directivity is weak. Therefore, the door key can be easily locked and unlocked without worrying about the position of the vehicle. In addition, it is possible to easily find one's own vehicle from a distance by an answer back using a hazard lamp or the like. This radio wave type keyless entry system communicates with each other by radio waves between the vehicle and the portable electronic key, so that even the operation switch of the portable electronic key does not need to be operated. Some have become more sophisticated (smart) so that they can be unlocked just by approaching. In this way, the radio wave type keyless entry system can be highly convenient.

  However, on the other hand, since the directivity of radio waves is weak, there are various problems to be solved regarding security. For example, one is that radio waves are received behind the scenes and information is easily copied. Moreover, it is difficult to lock and unlock each door. Further, it is possible that the door is locked and the portable electronic key is locked in the vehicle due to an unexpected press of the operation switch of the portable electronic key. Further, when the portable electronic key is transferred to a malicious third party due to loss or the like, the third party can easily find a vehicle that can use the portable electronic key by answer back.

  Many proposals have been made for these solutions. For example, Japanese Patent Application Laid-Open No. H10-228867 describes that fingerprint data or the like is used to authenticate whether the user of the portable electronic key is valid. In this way, some of the above problems are considered to be solved, but the system such as a structure for properly identifying fingerprint data or the like becomes complicated.

  On the other hand, an infrared keyless entry system using infrared rays as a radio signal is more susceptible to obstacles than the radio wave type because the directivity of infrared rays is stronger than that of radio waves. Proposals have been made to take advantage of this to solve some of the above security problems.

  For example, Patent Document 2 describes a vehicle in which a radiation angle of infrared light projection is a narrow angle, and a vehicle is provided with a plurality of unit sections mounted with a receiving element and a transmitting element via a partition wall. In this way, it is possible to lock and unlock only the desired door.

JP 2003-178032 A JP 2008-248567 A

  However, even if the directivity of infrared rays is stronger than that of radio waves, in Patent Document 2, it is considered that the structure of the partition walls and the like is complicated in order to ensure that only a desired unit section can be irradiated with infrared rays. The complexity of the structure is the same as in Patent Document 1, but it tends to cause instability of the system operation and high price.

  The present invention has been made in view of the above reasons, and an object of the present invention is to provide a keyless entry system in which the reliability of security can be improved without complicating the structure.

  In order to achieve the above object, a keyless entry system according to claim 1 includes: an operation switch; and a transmitting element that emits a visible light signal wave on which command data is superimposed in accordance with an operation of the operation switch. A vehicle having a portable electronic key and a receiving element capable of receiving the signal wave from the transmitting element, and locking or unlocking a door when the receiving element receives the signal wave superimposed with the command data It is characterized by comprising.

  A keyless entry system according to a second aspect is the keyless entry system according to the first aspect, wherein the transmitting element is operated when the operation switch for locking is operated and the command data for locking is superimposed. When the operation switch for locking is operated and the command data for unlocking is superimposed, the signal wave of visible light of a different color is emitted.

  The keyless entry system according to claim 3 is the keyless entry system according to claim 1 or 2, wherein the portable electronic key has a mechanical key portion extending from one end thereof, and the signal A wave is radiated in the extending direction of the mechanical key.

  The keyless entry system according to claim 4 is the keyless entry system according to any one of claims 1 to 3, wherein the portable electronic key has a radiation range of the signal wave from the portable electronic key to the outside. It can be controlled to change.

  The keyless entry system according to claim 5 is the keyless entry system according to any one of claims 1 to 4, wherein the receiving element is provided such that a receiving surface appears on an outer surface of the door of the vehicle. Alternatively, the receiving surface is provided so as to face the window glass inside the window glass.

  The keyless entry system according to claim 6 is the keyless entry system according to any one of claims 1 to 5, wherein the vehicle has a second transmitting element that transmits a second signal wave. And the portable electronic key has a second receiving element capable of receiving the second signal wave, and the portable electronic key radiates the signal wave of a request for challenge data from the transmitting element. When the receiving element receives the signal wave of the challenge data request, the vehicle emits the second signal wave on which the challenge data is superimposed from the second transmitting element, and the portable electronic key is When the second receiving element receives the second signal wave on which the challenge data is superimposed, the signal wave on which the command data with response data corresponding to the challenge data is superimposed Characterized in that emanating from the serial transmitting device.

  The keyless entry system according to claim 7 is the keyless entry system according to claim 6, wherein the signal wave of the challenge data request is a signal wave of only a carrier wave.

  According to the present invention, a visible light signal wave is used as a radio signal transmitted from the transmitting element of the portable electronic key to lock or unlock the door of the vehicle. It is possible to provide a keyless entry system in which the reliability of the device is improved.

It is a mimetic diagram for explaining keyless entry system 1 concerning an embodiment of the present invention. It is a block diagram of the portable electronic key 3 of the keyless entry system 1 same as the above. It is a circuit block diagram of the portable electronic key 3 of the keyless entry system 1 same as the above. It is a wave form diagram which shows the signal wave of each part of the portable electronic key 3 of the keyless entry system 1 same as the above. It is a flowchart which shows the operation | movement flow of the keyless entry system 1 same as the above. It is a block diagram of the thing of a different structure of the portable electronic key 3 of the keyless entry system 1 same as the above. It is a block diagram of the thing of another different structure of the portable electronic key 3 of the keyless entry system 1 same as the above. It is a circuit block diagram of the receiving circuit 20 of the vehicle 2 of the keyless entry system 1 same as the above. It is a partial schematic diagram for demonstrating the keyless entry system 1 'same as the above. It is a circuit block diagram of the portable electronic key 3 'of the keyless entry system 1' described above. It is a flowchart which shows the operation | movement flow of keyless entry system 1 'same as the above. It is a circuit block diagram of the receiving circuit 20 'of the vehicle 2 of the keyless entry system 1'.

  Hereinafter, preferred embodiments for carrying out the present invention will be described with reference to the drawings. As shown in FIG. 1, the keyless entry system 1 according to the embodiment of the present invention performs a command for locking and unlocking the door of the vehicle 2 by a signal wave S that is a radio signal from the portable electronic key 3. . It should be noted that this signal wave S is visible light.

  As shown in FIG. 2, the portable electronic key 3 is used for locking or unlocking operation switches (in this embodiment, two button switches) 31, 31 and for pressing the operation switches 31, 31. Correspondingly, it has a transmitting element 32 that emits a visible light signal wave S on which command data is superimposed. The signal wave S is radiated from the one end 3a of the portable electronic key 3 at a predetermined radiation angle. This radiation angle can also be adjusted by using a lens. In this embodiment, the number of operation switches is two for locking and unlocking, and the signal wave S on which the command data for locking or the command data for unlocking is superimposed is emitted. The number of operation switches 31 can be easily reduced to one. In this case, the portable electronic key 3 emits a signal wave S on which one kind of command data is superimposed, and the receiving circuit 20 of the vehicle 2 is locked or unlocked according to the current door state of the vehicle 2. Will be judged. The appearance of the portable electronic key 3 can be changed as appropriate.

  The portable electronic key 3 has an electronic circuit therein, and as shown in FIG. 3, the portable electronic key 3 generates locking or unlocking command data in accordance with the pressing operation of the operation switches 31 and 31. The data generation circuit 33, the carrier generation circuit 34 that generates a train (carrier wave) of a pulse p having a predetermined frequency (for example, 10 to 100 kHz), and the instruction data from the data generation circuit 33 are superimposed on the carrier wave of the carrier generation circuit 34. And a signal wave generation circuit 35 that generates the signal wave. The signal wave generated by the signal wave generation circuit 35 is input to the transmitting element 32 and converted into a visible light signal wave S.

  The signal wave generation circuit 35 superimposes the command data on the carrier wave by modulating the command data with the carrier wave. The modulation method may be a pulse position modulation (PPM), an inverted pulse position modulation (IPPM), or a pulse width modulation (PWM). That is, the signal wave of the signal wave generation circuit 35 represents one of the binary values of the command data bits depending on the position and width of the period T in which the carrier wave exists (carrier wave existence period) T. FIG. 4 shows, as an example, bit changes in the case of pulse position modulation, where (a) is before modulation, (b) is after modulation, and (c) is after conversion to a signal wave S of visible light. Shows things.

  The portable electronic key 3 can operate according to the flow on the left side of the flowchart shown in FIG. That is, when one of the two operation switches 31 and 31 is pushed down, it is detected that the operation has been performed (S301), and whether or not the operation switch 31 for locking is operated. Is determined (S302). If the operation switch 31 for locking is operated, the lock generation command data (S303) is generated by the data generation circuit 33. Otherwise, the lock generation command data (S304) is generated. Then, a signal wave S on which the command data is superimposed is emitted from the transmitting element 32 (S305).

  Thus, the portable electronic key 3 radiates the signal wave S on which the command data is superimposed from the transmitting element 32 in accordance with the operation of the operation switches 31 and 31. When the number of operation switches 31 is one as described above, steps S302 to S304 in FIG. 5 are replaced with one type of command data generation.

  The transmitting element 32 is preferably an LED that emits light in a predetermined color from the viewpoint of price and performance. Although there is no limitation on the color of the light emission, if a single color such as red, orange, or yellow is used, a difference from natural light is likely to occur. Therefore, in the receiving circuit 20 described later of the vehicle 2, the receiving surface of the receiving element 21 is received. By providing a color filter or the like on the outer side of 21a, mixing of noise is reduced.

  There may be one transmitting element 32 as long as an appropriate luminous intensity can be obtained, but two or more transmitting elements 32 may be provided. In this case, for example, the locking operation switch 31 is operated in such a manner that another transmitting element 32 that emits a signal wave S of visible light of a different color is provided in parallel to one transmitting element 32. When the unlocking command data is superimposed and when the unlocking operation switch 31 is operated and the unlocking command data is superimposed, the visible light signal wave S of a different color is emitted. It is also possible to do so. In this way, the portable electronic key 3 can be operated while confirming whether locking or unlocking is instructed.

  Various structures of the portable electronic key 3 are possible. For example, as shown in FIG. 6, the portable electronic key 3 has a mechanical key 3 </ b> A extending from one end 3 a, and the signal wave S from the transmitting element 32 is a mechanical key. It is radiated in the extending direction of 3A. If it does in this way, it will become possible to illuminate mechanical key part 3A, when inserting mechanical key part 3A in an engine key hole, and starting an engine. In addition, it is also possible to change the position of the transmitting element 32 or increase the number of the transmitting elements 32 as appropriate so that the shadow of the mechanical key unit 3A is not easily formed in the illumination. Further, even in the case of the portable electronic key 3 that does not have the mechanical key portion shown in FIG. 2, the visible light signal wave S from the transmitting element 32 can be used for illumination.

  Furthermore, it is also possible to control so that the radiation range of the signal wave S from the portable electronic key 3 to the outside changes. For example, as shown in FIG. 7, two transmitting elements 32 having the same performance are provided, and one transmitting element 32 is combined with a condensing lens 3B, and the other transmitting element 32 is combined with a diffusing lens 3C. As a result, a signal wave S1 having a relatively narrow radiation angle from one transmitting element 32 is emitted through the condenser lens 3B, and a signal wave S1 from the other transmitting element 32 is transmitted through the diffusion lens 3C to a relatively wide radiation angle. The signal wave S2 thus made can be radiated. For example, the radiation range of the signal wave S can be controlled by transmitting one of the two transmitting elements 32 and 32 according to the state of the switch 3D. Depending on the required radiation angle, either the condenser lens 3B or the diffusing lens 3C can be omitted. In addition, various methods for controlling the radiation range of the signal wave S can be applied. The irradiation range of the vehicle 2 is changed by controlling the radiation range of the signal wave S. For example, when a plurality of receiving elements 21 of the receiving circuit 20 described later are provided, the signal wave S is irradiated only at one place or at two places. Irradiation can be performed as described above.

  As shown in FIG. 1, the vehicle 2 has receiving circuits 20, 20,... That can receive a signal wave S from the transmitting element 32 of the portable electronic key 3. One or a plurality of receiving circuits 20 are provided according to the specifications of the vehicle 2.

  As shown in FIG. 8, the receiving circuit 20 includes a receiving element 21 that converts an input signal wave S into an electric signal. In addition, the receiving circuit 20 is a succeeding circuit of the receiving element 21, an amplifying circuit 22 that amplifies the electrical signal from the receiving element 21, and a bandpass that filters the output signal and extracts a frequency component near the carrier wave of the signal wave S The filter 23, the comparator 24 that compares the output signal with a predetermined threshold value and converts it into a binary value, and the lock command data and the unlock command data superimposed on the signal wave S are discriminated from the output signal to determine the door And a lock control circuit 25 that controls locking or unlocking. The detailed configuration of these receiving elements 21 and subsequent circuits can be realized by applying each known technique.

  The receiving circuit 20 can operate according to the flow shown on the right side of the flowchart shown in FIG. That is, when the signal wave S is received from the portable electronic key 3, the data superimposed thereon is returned to the state before modulation (S201), and the lock control circuit 25 determines whether the data is the lock command data or the unlock command data. (S202). If the command data is locking, the door is locked (S203). If the command data is unlocking, the door is unlocked (S204).

  Thus, the receiving circuit 20 of the vehicle 2 locks or unlocks the door when the receiving circuit 20 receives the signal wave S on which the command data is superimposed. When the number of operation switches 31 of the portable electronic key 3 is set to one and the signal wave S on which one type of command data is superimposed is transmitted as described above, the lock control is performed in step S202 in FIG. The circuit 25 will determine the current door state of the vehicle 2.

  The receiving circuit 20 can be provided in various places. In particular, the receiving circuit 20 is provided so that the receiving surface 21a of the receiving element 21 appears on the outer side surface of the door of the vehicle 2, or the receiving surface 21a of the receiving element 21 inside the window glass (side glass, windshield, rear glass, etc.). Is preferably provided so as to face the window glass (see FIG. 1). In this way, since only the signal wave S from the outside of the vehicle 2 is input, the door is locked and the portable electronic key 3 is prevented from being confined in the vehicle by the unexpected pressing of the operation switch 31 from the vehicle. be able to.

  In the keyless entry system 1 including the vehicle 2 and the portable electronic key 3, since the visible light signal wave S has a strong directivity and is visible, a signal in which command data is superimposed from the portable electronic key 3. It can be visually recognized that the wave S is properly radiated to the receiving element 21 of the vehicle 2. By doing so, command data (particularly command data for unlocking) is not received and copied behind the scenes. A light emitting element indicating that the receiving element 21 is appropriately receiving may be provided in the vicinity of the receiving element 21.

  Further, since the directivity of the signal wave S of visible light is strong, the outer surface of each door (for example, every door such as a driver's seat door, a passenger seat door, a back door, etc.) The receiving surface 21a of the receiving element 21 appears so as to appear (see FIG. 1), or the receiving surface 21a of the receiving element 21 faces the window glass inside the door window glass. It becomes easy to make specifications that can be individually locked and unlocked for some (or all) doors. In addition, the receiving circuit 20 that can lock and unlock all doors can be provided at any location (for example, near the top of the windshield or near the top of the rear glass) (see FIG. 1). Further, since the signal wave S is visible, it is possible to selectively irradiate the receiving elements 21 and 21 of the two receiving circuits 20 and 20 simultaneously or individually irradiate them. .

  In addition, when the portable electronic key 3 is transferred to a malicious third party due to loss or the like, the third party will try a number of other vehicles to find the vehicle 2, but the operation is It appears clearly suspicious to the side.

  As described above, the keyless entry system 1 can improve security reliability without complicating the structure. In addition, as a trade-off with security reliability, the additional function that is possible with the radio wave type such as finding the vehicle 2 from a distance is not easy as it is, but there are various functions such as separately providing a card having the function. It is possible to deal with it.

  The keyless entry system 1 using the signal wave S of visible light described above can be mixed with a radio wave type or infrared type system. That is, for the radio wave type mix, the portable electronic key 3 and the receiving circuit 20 of the vehicle 2 further have antennas, and either the locking or unlocking command data is superimposed on the visible light signal wave S. It is also possible to superimpose others on radio wave signal waves. For example, when the unlocking command data is superimposed on the signal wave S and the locking command data is superimposed on the radio wave signal wave, the unlocking command data is not received and copied behind the scenes, but for each door. Unlocking can be easily performed, and theft when the portable electronic key 3 is transferred to a malicious third party can also be suppressed. Further, by operating the operation switch 31 for locking, the vehicle 2 can be locked or found from a distance. On the other hand, when the door is locked by the unexpected pressing of the operation switch 31 and the portable electronic key 3 is confined in the vehicle, it cannot be locked from the vehicle or a spare unlocking method is provided. Become.

  For example, when the command data for locking is superimposed on the signal wave S of visible light and the command data for unlocking is superimposed on the signal wave of radio waves, the door is locked by the unexpected operation switch 31 and the portable electronic It is possible to prevent the key 3 from being trapped in the vehicle, but on the other hand, the unlocking command data is received and copied in the shade, the door-to-door unlocking and the mobile electronic key 3 are malicious third parties. Other measures are necessary for theft in case of crossing.

  Similarly, for the mix with the infrared type, the portable electronic key 3 has an infrared transmitting element, and the receiving circuit 20 of the vehicle 2 has an infrared receiving element, so that either the locking or unlocking command data is received. It is also possible to superimpose on the visible light signal wave S and superimpose others on the infrared signal wave. The effect of using two visible rays and infrared rays is almost the same as the above case using two visible rays and radio waves.

  Next, a keyless entry system 1 ′ in which the security of the keyless entry system 1 is further improved will be described with reference to FIGS. The keyless entry system 1 described above sends a command unilaterally from the portable electronic key 3 to the vehicle 2. This keyless entry system 1 ′ includes the portable electronic key 3 ′ and the vehicle 2 as shown in FIG. 9. Two-way communication is performed with the receiving circuit 20 ′, and safety is confirmed by challenge-response type authentication. Then, a command is sent from the portable electronic key 3 ′ to the vehicle 2.

  The signal wave S from the portable electronic key 3 ′ to the receiving circuit 20 ′ is visible light as described above. However, for transmission from the receiving circuit 20 ′ to the portable electronic key 3 ′, visible light, infrared light, radio waves, etc. It is possible to use the second signal wave T generated by any one of electromagnetic waves including, or sound waves or ultrasonic waves. In particular, when infrared light is used for the second signal wave T, it can be transmitted from a transmitting surface 29a of a second transmitting element 29 described later in the receiving circuit 20 'to a portable electronic key 3' within a required angle range, It is easy to prevent the surroundings from being affected and the transmission range from being too wide.

  As shown in FIG. 10, the electronic circuit of the portable electronic key 3 ′ is a second circuit that converts the second signal wave T from the receiving circuit 20 into an electric signal in addition to the circuit described with reference to FIG. 3. Receiving element 36, an amplification circuit 37 that amplifies the electric signal from the second receiving element 36, and a bandpass that filters the output signal to extract only the frequency component of the second signal wave T near the carrier wave described later. The filter 38, the comparator 39 that compares the output signal with a predetermined threshold value and converts it into a binary value, and the challenge data superimposed on the second signal wave T is extracted from the output signal, and the data generation circuit 33 described above is extracted. And the challenge data extraction circuit 40 that outputs the data. Detailed configurations of the second receiving element 36 and its subsequent circuits can be realized by applying respective known techniques.

  The portable electronic key 3 'can operate according to the flow shown on the left side of the flowchart shown in FIG. That is, when one of the two operation switches 31, 31 is pressed, it is detected that the operation has been performed (S301), and a signal wave S for requesting challenge data to the reception circuit 20 ′ is transmitted. The light is emitted from the element 32 (S310). Thereafter, the second signal wave T superimposed with the challenge data transmitted from the receiving circuit 20 'is received, and the challenge data extracting circuit 40 extracts the challenge data (S311). In response to the challenge data, the data generation circuit 33 operates the locking operation switch 31 if the operation is performed, the lock command data with the response data (S303 ′), and the unlocking operation switch 31. Then, unlock command data (S304 ′) with response data is generated. And the signal wave S with which those data were superimposed is radiated | emitted from the transmission element 32 (S305). In general, the challenge data is a random number, and the response data is data determined in advance according to the random number.

  Here, when the portable electronic key 3 ′ requests challenge data from the reception circuit 20 ′, a signal wave S of only a carrier wave (a train of pulses p having a predetermined frequency described above) is transmitted to request challenge data. Also good. By doing so, the time required for challenge-response type authentication can be shortened.

  As shown in FIG. 12, in addition to the above-described circuit described with reference to FIG. 8, the reception circuit 20 ′ generates a challenge data generation circuit that generates challenge data when the lock control circuit 25 determines a challenge data request. 26, a carrier wave generation circuit 27 that generates a carrier wave of a predetermined frequency, a signal wave generation circuit 28 that generates a signal wave in which challenge data is superimposed on the carrier wave of the carrier wave generation circuit 27, and a second signal corresponding to the signal wave. And the second transmitting element 29 that transmits the signal wave T. The transmission surface 29 a of the second transmission element 29 is disposed in the vicinity of the reception surface 21 a of the reception element 21.

  The receiving circuit 20 'can operate according to the flow shown on the right side of the flow chart shown in FIG. That is, when a signal wave S for requesting challenge data is received from the portable electronic key 3 ′ (S211), the challenge data is generated by the challenge data generation circuit 26 (S212), and the second signal is superimposed on the carrier wave. A wave T is transmitted from the second transmitting element 29. After that, after receiving the visible light signal wave S on which the data is superimposed, the operation is performed in the same manner as the flow described above with reference to FIG.

  Although the keyless entry system according to the embodiment of the present invention has been described above, the present invention is not limited to the one described in the embodiment, and various design changes within the scope of the matters described in the claims. Is possible. For example, the operation switch is not limited to a button switch, and various types such as a rotation type, a pressure-sensitive type, and a capacitance type are possible.

DESCRIPTION OF SYMBOLS 1 Keyless entry system 2 Vehicle 20 Receiving circuit of vehicle 21 Receiving element 21a Receiving surface of receiving element 3 Portable electronic key 31 Operation switch 32 Transmitting element 3A Mechanical key S S Visible light signal wave

Claims (7)

A portable electronic key having an operation switch and a transmitting element that emits a signal wave of visible light on which command data is superimposed in accordance with an operation of the operation switch;
A vehicle that has a receiving element capable of receiving the signal wave from the transmitting element, and that locks or unlocks a door when the receiving element receives the signal wave on which the command data is superimposed;
A keyless entry system characterized by comprising: The keyless entry system according to claim 1,
The transmitting element is operated when the operation switch for locking is operated and the command data for locking is superimposed, and when the operation switch for unlocking is operated and the command data for unlocking is superimposed. Then, in the keyless entry system, the signal wave of visible light of different colors is emitted. The keyless entry system according to claim 1 or 2,
The portable electronic key has a mechanical key portion extending from one end thereof, and the signal wave is radiated in the extending direction of the mechanical key portion. The keyless entry system according to any one of claims 1 to 3,
The keyless entry system, wherein the portable electronic key is controllable so that a radiation range of the signal wave from the portable electronic key to the outside is changed. In the keyless entry system according to any one of claims 1 to 4,
The keyless entry system, wherein the receiving element is provided such that a receiving surface appears on an outer side surface of the door of the vehicle, or is provided inside the window glass so that the receiving surface faces the window glass. . In the keyless entry system according to any one of claims 1 to 5,
The vehicle has a second transmitting element that transmits a second signal wave,
The portable electronic key has a second receiving element capable of receiving the second signal wave,
The portable electronic key radiates the signal wave of a challenge data request from the transmitting element,
When the receiving element receives the signal wave of the challenge data request, the vehicle radiates the second signal wave on which challenge data is superimposed from the second transmitting element,
When the second receiving element receives the second signal wave on which the challenge data is superimposed, the portable electronic key transmits the signal wave on which the command data with response data corresponding to the challenge data is superimposed. A keyless entry system radiating from the transmitting element. The keyless entry system according to claim 6,
The keyless entry system, wherein the signal wave of the challenge data request is a signal wave of only a carrier wave.

Images