JP3314465B2 - Keyless entry system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a keyless entry system mainly used for automobiles.

[0002]

2. Description of the Related Art A conventional technique will be described with reference to FIGS. Conventionally, a keyless entry system of this type is transmitted from the transmitter 2 by operating a switch 2b of the transmitter 2 having an oscillation circuit 5 for generating an airborne signal independent of an automobile and a power supply 6, and a switch 2b of the transmitter 2. The light-receiving unit 15 mounted on the automobile 1 for receiving the coded signal a transmitted from the transmitter 2 , the power supply device 7, and the only coded signal b the storage unit 8 housed, is composed of a receiver 3 and a comparator 9 for comparing the received encoded signal a at the light receiving portion 15, both of the coded signal a and b coincide If you do
A door lock / unlock signal is output to the controller 4.

An example of the configuration of the coded signal a or b will be described with reference to FIGS. 7A to 7C.
It is composed of 4 bits, and one pulse width t is 0.6
[Msec] at a frequency of about 40 [KHz]. The interval between each pulse is "0" when the interval is 2t, "1" when the interval is 4t, and is coded as a coded signal with binary numbers "0" and "1" and transmitted as a coded signal a.

[0004]

However, since the conventional keyless entry system has a simple coded signal a, it has a copy function like a commercially available learning remote controller.
The coded signal is easily copied by the copying apparatus having the above, and there is a problem in security.

An object of the present invention is to solve such a conventional problem, and an object of the present invention is to provide an excellent keyless entry system capable of maintaining security by preventing a coded signal from being copied. It is.

[0006]

Means for Solving the Problems The present invention, in order to solve the above problems, the coded signal from the transmitter to at least two continuous transmission or a coded signal of the two successive sending first and
A dummy code which is a dummy signal different from the coded signal is set at any time during the continuous transmission of the coded signal so that the code is incremented and made different in the second time , and further, the coded signal storage capacity of the learning remote controller overflows. It is intended to be inserted.

[0007]

Therefore, according to the present invention, the coded signal from the transmitter is transmitted at least twice, and the coded signal of the double transmission is changed before and after, and further different from the coded signal. by inserting a dummy signal before, during continuous feeding of the coded signal, the other to be copied
Overflow of the storage capacity of the copy device, and
It is intended to improve the security of the keyless entry system by confusing the identification of the code.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. The same parts as in the prior art will be described with the same reference numerals. According to FIG. 1, reference numeral 1 denotes an automobile, 2a denotes a transmitter, 3a denotes a receiver, 4 denotes a controller, and the transmitter 2a includes a switch 2b, an oscillation circuit 5a, a power supply 6, and the like, and the receiver 3a receives light. It comprises a unit 15, a power supply unit 7, a storage unit 8a, and a comparator 9a. FIG. 3 shows the entire transmission signal of the present invention, and the coded signal 10
And a dummy code 11 serving as a dummy signal, and a coded signal 12 obtained by incrementing the coded signal 10.

Next, the details of the configuration of the above embodiment will be described together with the operation. When the operation switch 2b of the transmitter 2a is pressed,
The oscillation circuit 5a operates, the transistor 13 is driven by the oscillation output, and a transmission signal is output from the infrared light emitting diode (hereinafter, referred to as LED) 14. Receiving a transmission signal from LED14 receiving section 15 of the receiver 3a, by changing the optical signal into an electric signal, by comparing the signals stored in advance in the storage unit 8a the comparator 9a, the signal is identical If so, a door lock or unlock signal is output.
If the compared signals are different, the lock and unlock signals are not output.

[0010] Next to the calling Fukairo 5a is describing an example of a coded signal transmitted, first as shown in FIGS. 4 (a)
The coded signal 10 is divided into “0” and “1” according to time t by dividing a 24-bit signal by 25 pulses,
4B. The second coded signal 12 which has been transmitted in the form of 000000000000000000001 and which has been continuously transmitted is 1000000000000 which is obtained by incrementing the first coded signal 10 by one as shown in FIG.
000000000010 and transmitted.

The dummy code 11 which is a dummy signal inserted between the first coded signal 10 and the second coded signal 12 has a pulse width t and a pulse interval that are different from those of the normal coded signal. In consideration of the response speed (delay time) of the receiver 3a with a different width, it is set to 0.1 [msec],
Assuming that the number of pulses is 200 bits, the total number of bits is 248 bits as shown in FIG.

[0012] According to the above embodiment, first the entire transmission signal, and transmitting at least two continuous transmissions over a second coded signal 10, 12, and, it the dummy signal
The first and second coded signals 10 and 12 are incremented by the first and second times to obtain different signals, so that the coded signals are copied. Is also a dummy code 1 that becomes a dummy signal.
Storage capacity of the other copying machines by 1 (not shown) ends up overflow (generally the capacity of the copy equipment having a copy function is about 150Bit), and,
Even when transmission output if copying within the memory capacity, since the first and different encoding signal increments the second coded signal 10 and 12, the receiver 3
The a side cannot determine that the signal is a coded signal.
There is no possibility of the door being unlocked, and security is improved.

In the above embodiment, (the coded signal 10 + the dummy code 11 + the coded signal 12) is stored in the transmitter 2a in advance, and the same coded signal is stored in the storage 8a of the receiver 3a. I explained it as a thing to keep,
A coded signal memory means and a calculation means are provided in the oscillation circuit 5a of the transmitter 2a, and the coded signal from the coded signal memory means is incorporated into the calculation means for calculating a prescribed number of times, and the coded signal is coded each time the calculation is performed. signal incremented is <br/> Re and, so as to be transmitted as coded signals, further provided with a dummy code generating means, and transmits the inserted dummy code from the dummy code means between appropriately the coded signal By doing so, the transmitter 2a can transmit a large capacity transmission signal without having a large memory capacity.

Also, in the receiver 3a, by providing a dummy code removing means in the stage before the received coded signal before the comparator 9a, only the coded signal needs to be compared, so that the receiver 3a The memory capacity of the storage unit 8a can be reduced.

[0015]

According to the present invention as is clear from the above embodiments, sends a coded signal 2 successive sending more, different coded signals once <br/> first and second coded signals Let
Furthermore, those with improved security automotive keyless entry system by adding a dummy code to code signal as larger than the memory capacity of the commercially available copying machines.

[Brief description of the drawings]

FIG. 1A is a block diagram of a transmitter as a main part of the keyless entry system of the present invention. FIG. 1B is a block diagram of a receiver as the main part.

FIG. 2 is an explanatory diagram illustrating an outline of the system.

FIG. 3A is an overall view of the transmission signal. FIG. 3B is a coded signal diagram as a main part of the transmission signal. FIG. 3C is a dummy code diagram as a main part of the transmission signal.

[4] (a) a pulse waveform diagram of increment the coded signal a coded signal of a pulse waveform diagram of the coded signal (b) (a)

FIG. 5 is an explanatory diagram illustrating an outline of a conventional keyless entry system.

FIG. 6A is a block diagram of the transmitter. FIG. 6B is a block diagram of the receiver.

7A is an overall view of the transmission signal, FIG. 7B is a coded signal diagram as a main part of the transmission signal, and FIG. 7C is a pulse waveform diagram showing the state of 0, 1 determination.

[Explanation of symbols]

 2a transmitter 3a receiver 4 controller 5a oscillation circuit 6 power supply 8a storage 9a comparator 10 coded signal 11 dummy code

──────────────────────────────────────────────────の Continuation of the front page (51) Int.Cl. ⁷ identification code FI H04Q 9/00 311 H04Q 9/00 311N (58) Field surveyed (Int.Cl. ⁷ , DB name) E05B 1/00-75 / 00 H03J 9/00-9/06 H04Q 9/00-9/16

Claims (1)

(57) [Claims] 1. A a transmitter having a transmission means to transmit the coded signal, reception hand stage for receiving the coded signal from the transmitter, the same code as the coded signal of the transmitter
Storage unit which has previously stored a de signal, pre-serial coded signal and the storage device received by the receiving means
By comparing the憶code signal, in the keyless entry system comprising a receiver equipped with both are to issue a signal when a match comparator, a code signal from the transmitter at least Two consecutive transmissions , and the second coded signal of the two consecutively coded signals is the first
Varied increments over de signal, still another co
The first time to overflow the storage capacity of the
Keyless entry system, characterized in that placed in one of the front and rear in-the feed Duplicate different dummy signal the encoded signal and the second coded signal.