EP0816599B1 - Device for remote control of a garage door - Google Patents

Description

The invention relates to a device for remote control of a garage door according to the preamble of claim 1.

It is known from the motor vehicle using a handheld transmitter Open garage door remotely. The delivered by the broadcaster Signals are picked up by the receiver on the garage door, which controls the garage door drive accordingly so that the garage door is closed or opened. The between transmitter and Signals transmitted to receivers can be intercepted and deciphered be so that there is a risk that the garage door by unauthorized persons is opened, for example while the house is empty.

To avoid this, a device is known (EP-A-0 492 692), where the signals between the transmitter and the receiver be encrypted using the RSA method.

In another known remote control (US-A-5 471 668) that for video recorders, televisions, microwave ovens, refrigerators and The same is provided for encryption and decryption a rolling code is used.

It is known in a unidirectional door opener system (EP-A-0 697 491), a rolling code for the encryption of signals use.

It is also known (US-A-5 515 036) for a keyless entry Opening system for vehicles the signals between a transmitter and encrypt a recipient.

The invention is based, the generic device the task to train so that with simple and reliable training remote opening of the garage door by unauthorized persons not possible.

This object is achieved according to the invention in the generic device with the characterizing features of claim 1 solved.

In the device according to the invention, the transmitter signals encrypted using a rolling code using the RSA method. This ensures that the remote control signals do not have to be deciphered, even if the calculation algorithm used is known. This prevents unauthorized parties from leaving intercepted remote control signals the opening code for the garage door can decipher. The antenna signal of the transmitter or Receiver is mixed with the oscillator frequency. The antenna of the transmitter or the receiver as well as the oscillator are connected to the Mixing element connected. In it the antenna reception frequency mixed with the frequency of the oscillator. The output signal of the mixing element is fed to the filter, which is the difference frequency sieves from reception and oscillator frequency. The output signal of the filter is evaluated in the microprocessor and used for Control of the switch of the receiver used. He can can be connected to existing garage door controls. The receiver thus forms an adapter with the existing one Garage door drives subsequently with the invention Device can be equipped. Further advantageous features of the invention result from the others Claims, the description and the drawings.

Fig. 1

in schematischer Darstellung ein Fahrzeug vor einem Garagentor, das mittels einer erfindungsgemäßen Vorrichtung geöffnet bzw. geschlossen werden kann,

Fig. 2

in einer Prinzipdarstellung die Wirkungsweise eines kraftfahrzeugseitigen Senders der erfindungsgemäßen Vorrichtung,

Fig. 3

in einer Prinzipdarstellung die Wirkungsweise eines garagentorseitigen Empfängers der erfindungsgemäßen Vorrichtung,

Fig. 4

in einer Darstellung entsprechend Fig. 1 eine zweite Ausführungsform einer erfindungsgemäßen Vorrichtung,

Fig. 5

Sende- und Empfangsdaten der Vorrichtung gemäß Fig. 4,

Fig. 6

ein Blockschaltbild des kraftfahrzeugseitigen Senders der erfindungsgemäßen Vorrichtung,

Fig. 7

ein Blockschaltbild des garagentorseitigen Empfängers der erfindungsgemäßen Vorrichtung,

Fig. 8

die von verschiedenen Sendern abgegebenen Signale.

The invention is explained in more detail with reference to exemplary embodiments shown in the drawings. Show it:

Fig. 1

a schematic representation of a vehicle in front of a garage door that can be opened or closed by means of a device according to the invention,

Fig. 2

the principle of the operation of a motor vehicle transmitter of the device according to the invention,

Fig. 3

a schematic representation of the mode of operation of a receiver on the garage door side of the device according to the invention,

Fig. 4

1 shows a second embodiment of a device according to the invention,

Fig. 5

Transmit and receive data of the device according to FIG. 4,

Fig. 6

2 shows a block diagram of the motor vehicle transmitter of the device according to the invention,

Fig. 7

2 shows a block diagram of the receiver on the garage door side of the device according to the invention,

Fig. 8

the signals emitted by different transmitters.

The device is used to remove a garage door 1 from a Motor vehicle 2 to open or close remotely conclude. The device is designed so that it connected to existing garage door controls can be. This makes it possible to do it later to assemble the device.

This device consists of two devices. The first The device is a vehicle-side transmitter 3 (FIG. 2), preferably in the inside mirror of the motor vehicle 2 is housed. The transmitter 3 can also in the exterior rearview mirror of the motor vehicle or within the Vehicle should be provided at a suitable location. It is of course also possible to use the transmitter 3 Training handheld device. The second device is a receiver 4 (Fig. 1 and 3), in the garage 5 at more suitable Place is arranged. The receiver 4 is with a drive 6 (Fig. 1) of the garage door 1 connected.

Remote control signals are transmitted with the transmitter 3, which are received and evaluated by the receiver 4.

Then the drive 6 of the garage door control actuated by the receiver 4 to open the garage door 1 or close. The signals between transmitter 3 and Receiver 4 are encrypted so that unauthorized People cannot open the garage door. The encrypted Signals cannot be heard by listening to the Transmission channel and replica of the transmitted Message will be decrypted. For this the RSA procedure uses a high security against decryption offers. This RSA process that with great Prime numbers as a key is known per se so that it will not be explained in detail. at knowledge of the didn't use the algorithm to crack the code; rather, all keys used must also be known his. Manchester coding is advantageous as the type of coding used, which is also known and is therefore not explained in more detail. With the Manchester coding a high level of interference immunity is guaranteed, because both a level and an edge evaluation the signals is possible.

1, it is assumed that that the corresponding remote control signals in encrypted Form sent from the transmitter 3 to the receiver 4 be that feedback from the receiver to the sender however does not take place. The device thus works unidirectional.

In Fig. 2 the operation of the transmitter 3 is schematic shown. The transmitter 3 calculates before everyone Transmission the message to be transmitted from a unique Number of the sender (device identifier), a pressed one Key and a consecutive number of the Transmission as well as the coding key RSA. From these the encrypted message is divided into four parts formed, which is sent to the receiver 4.

As can be seen from the schematic representation of the mode of action of the receiver 4 with reference to FIG. 3 results receive the encrypted message 7. The recipient 4 evaluates the consecutive number of the transmission (meter reading) and checks them for a valid value. there the current counter reading must always be greater than the last encryption key used. The overflow the counter is intercepted.

Because of the unidirectional transmission, it is not necessary, one in transmitter 3 and / or in motor vehicle 2 To provide receivers to the receiver 4 to receive transmitted signals. This will make it difficult to be expected when received in the motor vehicle are avoided. Such difficulties arise for example, from the directivity of one Receivers used ferrite antennas.

Due to the rolling code used in the RSA process is an excellent encryption, secure against eavesdropping of the signals to be transmitted guaranteed.

Fig. 4 shows schematically a bidirectional connection between the vehicle-side transmitter 3 and the garage-side Receiver 4. In this case, a mutual exchange of messages between senders 3 and receiver 4. For this reason the transmitter is 3 also provided with a receiving device. First is encrypted from the vehicle-side transmitter 3 Message 7 to the receiver 4 on the garage side sent. This message is, for example, like Fig. 5a shows a 32-bit signal that i.a. the device identifier, identifying the key identifier and the rolling code Contains bits. This 32 bit signal is received by the receiver 4 recorded and evaluated. He then sends one too encrypted signal 8 back to transmitter 3. It is for example a 32 bit signal (Fig. 5b) that the Device identifier of the receiver 4 (14 bit), two control bits as well as a rolling code of the receiver 4 (16 bit). This signal 8 is in turn evaluated by the transmitter 3. The transmitter 3 then sends a corresponding encrypted confirmation signal 9 to the receiver 4 back. This confirmation signal 9 can in turn be a 32nd Be bit signal (Fig. 5c), the bits for the device identifier of the transmitter 3, for the key identifier and a contains specified bit sequence. This specified bit sequence could be a rolling code, for example, to which an additional value is added.

This encrypted confirmation signal 9 is sent by the receiver 4 evaluated, which is then a corresponding encrypted Sends confirmation signal 10 to the transmitter 3. This confirmation signal can in turn be a 32 bit signal, the bits for the device identification of the Receiver 4, control bits and a fixed one Can contain bit sequence. This confirmation signal 10 is evaluated by transmitter 3. It then sends a final report 11 back to the receiver 4. It contains how Fig. 5d shows an example of bits for the device identifier of transmitter 3, for the key identifier and for the device identifier of the recipient 4. Only when this final protocol 11 received and evaluated by the receiver 4 is, it gives the appropriate signals to the controller the garage door operator 6.

This directional connection between transmitter 3 and receiver 4 ensures a high level of security against unauthorized persons Opening the garage door.

As shown in FIG. 6, the transmitter 3 has an antenna 12, preferably a ferrite antenna with which the corresponding Signals are sent to the receiver 4. At a The antenna 12 can also be bidirectional receive the signals coming from the receiver 4. The antenna signal is fed to a mixer 13, which also Signals from an oscillator 14, preferably a voltage-controlled one Oscillator (VCO) receives. The receiving frequency the antenna 12 and the oscillator frequency mixed in the mixer 13 and the difference frequency in one downstream baseband filter 15 sieved. The Signal of the baseband filter 15 is in a subsequent one Baseband amplifier 16, which is preferably regulated is amplified to a defined value. The output signal the baseband amplifier 16 becomes a microprocessor 17 fed to the oscillator 14 step by step votes on the receiving bands. The oscillator 14 is Part of a phase locked loop PLL in which the instantaneous phase of the voltage controlled oscillator 14 the current phase of the coming from the microprocessor 17 Input signals is tracked. To the microprocessor 17, an EEPROM 18 to be controlled in series is connected. The measured values are stored in it and also retrieved from the microprocessor 17 if necessary.

The transmitter 3 is also provided with a voltage regulator 19 provided to the voltage source of the motor vehicle 2 is connected. If the transmitter 3 is a handheld transmitter, it becomes independent of the current / voltage source of the Motor vehicle operated with batteries or rechargeable batteries. The Mixer 13, the baseband filter 15 and the baseband amplifier 16 are advantageously a component.

The receiver 4 (Fig. 7) has a similar structure as the transmitter 3. The receiver 4 has an antenna 20 provided, which is advantageously a wire antenna. she catches the signals emitted by transmitter 3. Moreover are over it with bidirectional connection between Transmitter and receiver corresponding signals from the Receiver 4 emitted. The antenna 20 is with a Mixer 21 provided in which the antenna reception frequency is mixed with the frequency of an oscillator 22 which advantageously a voltage controlled oscillator (VCO) is. The difference frequency from reception and oscillator frequency is in a downstream baseband filter 23 screened.

The baseband filter 23 is preferably a controllable one Baseband amplifier 24 downstream of the signal amplified to a defined peak before it a microprocessor 25 is supplied. Like the transmitter 3, the signals supplied to the microprocessor 25 evaluated and the measurement results stored in an EEPROM 26, from which the microprocessor the appropriate Can also retrieve values. Using the microprocessor 25, the oscillator 22 is in turn via the reception bands Voted. The oscillator 22 is part of one Phase locked loop PLL, in which the instantaneous phase of the oscillator 22 on the current phase of the microprocessor 35 incoming input signals is tracked. How at transmitter 3, the oscillator 22 and the phase locked loop are used PLL for frequency generation. The EEPROM 26 is advantageously controllable in series. The mixer 21, the baseband filter 23 and the baseband amplifier 24 advantageously a component.

A voltage regulator is used to supply the voltage to the receiver 4 27 provided.

A control relay 28 is connected to the microprocessor 25, that of the microprocessor 25 via a transistor T is controlled. With the control relay 28 be advantageously controlled three outputs of the receiver 4. Using these three outputs, different functions controlled. The outputs are NC contacts or capper provided. One of the exits should Can switch 220 V at 10 A. If necessary, too Overload protection can be provided to prevent overload of the receiver 4 and possibly the control of the garage door operator 6 to avoid.

The outputs of the receiver 4 can additional one have programmable time function. This time function could, for example, be designed so that the recipient 4 can only be activated at certain times of the day, received no signals during the rest of the time can, or that with opening the garage door 1 lamps be switched on.

The 40 MHz band is advantageously used as the carrier frequency. The intended phase locked loop PLL of the transmitter 3 and the receiver 4 leaves frequencies between 20 MHz and 60 MHz too. The type of modulation is advantageous Amplitude modulation used. To a high noise immunity to ensure is preferably a Negative modulation used.

If the receiver 4 in the manner described three Has outputs, then the transmitter 3 is advantageous with appropriate equipped with three function keys that the three outputs of the receiver 4 can be assigned. This Assignment is advantageously freely selectable, so that this Function buttons of transmitter 3 the corresponding outputs of the garage-side receiver 4 can be controlled can. The transmitter 3 advantageously has a basic setting, which is only required by the user of the transmitter 3 is changed.

The transmitter 3 is advantageously designed so that it, for example with regard to its identifier with a from User freely selectable number can be labeled. This also makes it possible, for example, to use this identification number change if necessary. This is an advantage if the transmitter 3 is designed as a hand transmitter and has been lost. In this case, with a new hand-held transmitter, the device ID number is reset become.

The receiver 4 can be advantageous with a learning mode be equipped. With a button or the like the microprocessor 25 is put into a learning mode, in which, for example, the identifier of a new handheld transmitter stores.

The microprocessor 25 can also operate in a lock mode become. The microprocessor then deletes the corresponding one Transmitter 3 that is operated. It can also the total memory can be deleted. Then if this or another transmitter started up again to be switched, the receiver 4 in the learning mode to save the identifier of the transmitter.

So with the simultaneous use of two or more Transmitters do not experience any malfunctions Transmitters have different repetition rates. Fig. 8 shows this using the example of three hand transmitters HS1 to HS3. Become for example, two hand transmitters operated at the same time, the receiver 4 reacts due to the different Repetition rates are not. Then becomes just a handheld transmitter actuated, the receiver 4 reacts at the next Signal. The transmission process is preferably shorter than 1 ms.

But it is also possible to use the transmitter 3 with several frequencies equip. The processor 25 searches in the given Frequency ranges according to the transmitter signals and it works almost in parallel.

The receiver 4 can be connected to existing garage door controls be connected. In this case it is the control relay 28 to the existing garage door drive 6 connected as an external switch. Such connectivity are available with every garage door operator, since the garage door 1 either via a button or a key switch is operated. The receiver 4 can be made very compact. Since the frequencies in Megahertz range, the device works on long distances, for example up to 60 m, perfectly.

Claims (9)

1. Device for remote control of a garage door (1), having at least one transmitter (3) which emits signals which are encrypted by applying a RSA method, and having at least one receiver (4) at the garage door end, which receiver (4) controls a drive (6) of the garage door (1), receives remote control signals from the transmitter (3) and is provided with a switch (28) which is connected to the garage door drive (6), characterized in that the signals which are output by the transmitter (3) are encrypted by applying the RSA method with a rolling code, in that the antenna signal of the transmitter (3) or of the receiver (4) is mixed with an oscillator frequency, in that an antenna (12, 20) of the transmitter (3) or of the receiver (4) and an oscillator (14, 22) are connected to a mixing element (13, 21) whose output signal is fed to a filter (15, 23) which filters out the differential frequency from the antenna signal and oscillator frequency, and in that the output signal of the filter (15, 23) is fed via an amplifier (16, 24) to a microprocessor (17, 25) to which the switch (28) is connected.
2. Device according to Claim 1, characterized in that the connection between the transmitter (3) and receiver (4) is unidirectional.
3. Device according to Claim 1, characterized in that the connection between the transmitter (3) and receiver (4) is bidirectional.
4. Device according to one of Claims 1 to 3, characterized in that the oscillator (14, 22) is voltage-regulated.
5. Device according to one of Claims 1 to 4, characterized in that the oscillator (14, 22) is part of a phase-locked loop (PLL).
6. Device according to Claim 5, characterized in that the output signal of the microprocessor (17, 25) is fed to the phase-locked loop (PLL).
7. Device according to one of Claims 1 to 6, characterized in that a memory (18, 26), preferably an EEPROM, is connected to the microprocessor (17, 25).
8. Device according to one of Claims 1 to 7, characterized in that the switch (28) is a relay.
9. Device according to one of Claims 5 to 8, characterized in that the phase-locked loop (PLL) comprises a frequency range between approximately 20 MHz and approximately 60 MHz.

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