(12) INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT)
`
`(19) World Intellectual Property Organization
`International Bureau
`
`1111111111111111 IIIIII 111111111111111 IIIII IIIII lllll lllll 11111111111111111111111
`
`(43) International Publication Date
`2 May 2002 (02.05.2002)
`
`PCT
`
`(10) International Publication Number
`WO 02/35036 Al
`
`(51) International Patent Classification 7:
`
`E05B 49/00
`
`(21) International Application Number:
`
`PCT/SE0l/02321
`
`(22) International Filing Date: 23 October 2001 (23.10.2001)
`
`(25) Filing Language:
`
`(26) Publication Language:
`
`Swedish
`
`English
`
`(30) Priority Data:
`0003833-1
`
`23 October 2000 (23.10.2000)
`
`SE
`
`(71) Applicant (for all designated States except US): VOLVO
`TEKNISK UTVECKLING AB [SE/SE]; S-405 08 Gote(cid:173)
`horg (SE).
`
`(72) Inventor; and
`(75) Inventor/Applicant (for US only): LUNDKVIST, Ola
`[SE/SE]; Nilssonsberg 10, S-411 43 Goteborg (SE).
`
`(74) Agent: FROHLING, Werner; Volvo Teknisk Utveekling
`AB, Corporate Patents, Dep. 06820, CTP, S-412 88 Gote-
`borg (SE).
`
`(81) Designated States (national): AE, AG, AL, AM, AT, AU,
`AZ, BA, BB, BG, BR, BY, BZ, CA, CH, CN, CO, CR, CU,
`CZ, DE, DK, DM, DZ, EC, EE, ES, Fl, GB, GD, GE, GH,
`GM, HR, HU, ID, IL, IN, IS, JP, KE, KG, KP, KR, KZ, LC,
`LK, LR, LS, LT, LU, LV, MA, MD, MG, MK, MN, MW,
`MX, MZ, NO, NZ, PH, PL, PT, RO, RU, SD, SE, SG, Sl,
`SK, SL, TJ, TM, TR, TT, TZ, UA, UG, US, UZ, VN, YU,
`ZA, ZW.
`
`(84) Designated States (regional): ARIPO patent (GH, GM,
`KE, LS, MW, MZ, SD, SL, SZ, TZ, UG, ZW), Eurasian
`patent (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), European
`patent (AT, BE, CH, CY, DE, DK, ES, Fl, FR, GB, GR, IE,
`IT, LU, MC, NL, PT, SE, TR), OAPI patent (BF, BJ, CF,
`CG, Cl, CM, GA, GN, GQ, GW, ML, MR, NE, SN, TD,
`TG).
`
`[Continued on next page}
`
`(54) Title: A METHOD FOR CONTROLLING AUTHORIZATION TO AN OBJECT AND A COMPUTER PROGRAM PROD(cid:173)
`UCT FOR THE AUTHORIZATION CONTROL
`
`(57) Abstract: The invention relates to a method for controlling authoriza(cid:173)
`tion for access to an object, in which a signal communication via electro(cid:173)
`magnetic waves is established between the object and a wireless portable
`unit when a tripping device on the object is actuated. The signal commu(cid:173)
`nication comprises at least one first signal (Xl...Xn) that is sent from the
`object to the portable unit, and at least one second signal (Y3, Zl ... Zn)
`that is sent from the portable unit to the object in response to said first sig(cid:173)
`nal(s). Said second signal(s) comprise sufficient information for verifying
`that the portable unit has an approved identity. The verification information
`is checked, a distance is measured between the object and the portable unit
`and the authorization is confirmed if both the checked verification infor(cid:173)
`mation is approved and the measured distance is less than a predetermined
`value. For the distance measurement, a time (T3) is measured for the trans(cid:173)
`mission of at least one of said first signals and at least one of said second
`signals with verification information.
`
`Tripping device
`la actuated
`
`M .... oexls
`~
`d•termined •nd
`,__ __ ~
`l
`x, .. .,.nt
`
`Xl Is received
`
`X1
`
`l{ ==1:!..hiand
`Z1
`~ Zllooont
`s !!J•;;:::::::i
`L - - - - - - '~ X:Z ls received b
`
`)(2
`
`i . . - -~ -~
`
`~ andX:Z lsunt
`
`-,
`"f"""
`
`22 Jo received - - - __.._ ___ _.
`andXJlsnn.t ~
`
`T3
`
`l
`1
`~ )
`Zn-.....___.,
`Zn II reciatvedand ---1--......---
`
`)(n
`
`Xn •• nKllliffd
`~ and Zn Is Hnt
`
`/\ •llldecrvpted
`
`J
`
`X la decrypted
`
`--iiiiiiiiiiii
`
`iiiiiiiiiiii
`iiiiiiiiiiii
`
`iiiiiiiiiiii -
`
`iiiiiiiiiiii
`
`iiiiiiiiiiii ----
`
`TCL Exhibit 1006
`
`

`

`WO 02/35036 Al
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`1111111111111111 IIIIII 111111111111111 IIIII IIIII lllll lllll 11111111111111111111111
`
`Published:
`-
`with international search report
`
`For two-letter codes and other abbreviations, refer to the "Guid(cid:173)
`ance Notes on Codes and Abbreviations" appearing at the begin(cid:173)
`ning of each regular issue of the PCT Gazette.
`
`TCL Exhibit 1006
`
`

`

`WO 02/35036
`
`PCT/SE0l/02321
`
`A method for controlling authorization to an object and a computer program
`product for the authorization control
`
`FIELD OF THE INVENTION
`
`5 The present invention relates to a method for controlling authorization for access to
`an object, in which a signal communication via electromagnetic waves is established
`
`between the object and a wireless portable unit when a tripping device on the object
`
`is actuated, the signal communication comprising at least one first signal that is sent
`
`from the object to the portable unit and at least one second signal that is sent from
`
`10
`
`the portable unit to the object in response to said first signal(s), in which said second
`
`signal(s) comprise sufficient information for verifying that the portable unit has an
`
`approved identity, in which the verification information is checked, in which a
`
`distance is measured between the object and the portable unit and in which the
`
`authorization is confirmed if both the checked verification information is approved
`
`15
`
`and the measured distance is less than a predetermined value. The predetermined
`
`value corresponds to a maximal permitted distance between the portable unit and
`
`the object.
`
`In addition, the invention concerns a method for controlling authorization for access
`
`20
`
`to an object according to the preamble to claims 8 and 11. The invention also
`
`concerns computer program products for such authorization control.
`
`The invention will be described below for authorization control for a vehicle, such as
`
`a car or truck. This is a preferred, but in no way limiting, application of the invention.
`
`25
`
`In such a case, the tripping device normally consists of a door handle on the vehicle.
`
`More specifically, the field of the invention is aimed at a so-called passive access
`
`control, which means that the person who is authorized to access the object does
`
`not need actively to use any key or remote control in order to unlock the object's
`
`30
`
`door. Instead, the authorization is checked automatically via the abovementioned
`
`signal communication using electromagnetic waves between the vehicle and the
`
`TCL Exhibit 1006
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`

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`WO 02/35036
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`PCT/SE0l/02321
`
`2
`
`wireless unit carried by the person, when the vehicle's door handle is actuated. The
`door is unlocked automatically in the event of approved authorization.
`
`PRIOR ART
`5 Patent US 5,723,911 relates to a device for controlling access to a motor vehicle.
`This control is designed to be carried out without the user needing to actuate any
`key. A distance detection device on a transceiver carried by the user is designed to
`detect the distance between the transceiver and the vehicle with the aim of reducing
`the risk of unauthorized access to the vehicle. The authorization control is carried
`out by a transmitter in the vehicle sending a call signal to a receiver in the
`transceiver when the vehicle's door handle is actuated. The transmitted signal has a
`short range. The transceiver's receiver receives the signal and sends a coded
`response signal back to the vehicle only if the vehicle is in the immediate vicinity of
`the transceiver. In other words, no response signal is sent back to the vehicle if this
`is not located in the vicinity of the transceiver. A receiving unit in the vehicle receives
`the response signal, checks it and sends an unlocking signal to the lock if the
`response signal is correct. The distance detection is carried out, for example, via
`transmission of a distance detection signal from the transceiver and reflection of this
`by the vehicle.
`
`1 O
`
`1 5
`
`20
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`25
`
`30
`
`The distance detection is carried out as mentioned above with the aim of reducing
`the risk of unauthorized access to the vehicle. Such unauthorized access to the
`vehicle has previously been possible by the use of a pair of receiver-transmitters in
`the following way: a first person with a first transmitter-receiver is in the vicinity of the
`vehicle while a second person with a second transmitter-receiver stands in the
`vicinity of the authorized user of the vehicle. The first person actuates the door
`handle of the vehicle, which initiates the signal communication. The signal (with a
`short range) from the vehicle's transmitter is received by the first person's receiver
`and forwarded with a long range to the transmitter-receiver of the second person
`and thereafter to the rightful user of the vehicle. In the same way, the coded signal is
`thereafter sent back from the portable unit to the vehicle via the two pairs of
`transmitters-receivers and authorization is confirmed.
`
`TCL Exhibit 1006
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`

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`WO 02/35036
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`
`3
`
`Using the distance detection device according to US 5,723,911, the time it takes for
`the electromagnetic waves or ultrasound waves to go from the portable unit to the
`object and back again is measured. If the rightful user is located at a great distance
`from the vehicle, the transmission of the ultrasound waves takes a long time. This is
`detected and a signal is not sent back to the vehicle from the portable unit.
`
`A problem with said distance detection device is that it is not possible to know for
`certain that it is the correct (authorized) portable unit that is in the vicinity of the right
`vehicle. In addition, known methods for distance detection, such as ultrasound
`echoes and metal detection, are relatively easy to deceive and thereby not secure.
`
`5
`
`10
`
`SUMMARY OF THE INVENTION
`A first aim of the invention is to achieve a method for controlling authorization to an
`object with increased security in relation to previous technology.
`
`1 5
`
`20
`
`This aim is achieved by measuring for the distance measurement a time for the
`transmission of at least one of said first signals and at least one of said second
`signals with verification information. In other words, the distance is determined
`between the object and the portable unit by measuring the time for at least part of
`the signal communication for the identity verification and it is ascertained that it really
`is the time between the correct portable unit and the object that has been measured.
`The signals for the identity control are thus used to determine whether the portable
`unit and the object are located sufficiently close to each other. This results in
`
`25
`
`increased security.
`
`Because the time is measured for the signals that are used for the identity control,
`the distance detection method that is separate to the identity control method
`according to previous technology is eliminated. In other words, according to the
`invention, the distance detection method is integrated in the identity control method.
`
`30
`
`TCL Exhibit 1006
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`4
`
`An encryption system is suitably utilized for said signals. A strong encryption
`algorithm is preferably utilized. There are a plurality of known such encryption
`algorithms, and for example so-called asymmetric key pairs are used, with the object
`holding one key and the portable unit the other key. Simpler types of encryption or
`coding can also be used, which will of course not provide such high security.
`
`According to a preferred embodiment, during the part of the signal communication
`that is used for the time measurement, a plurality of said signals are sent in series in
`such a way that alternate signals consist of one of said first signals and of one of
`said second signals. Because the time (and thereby any time deviation) for the
`consecutive signals, each of which has a very short transmission time, is totalled, it
`is thereby possible to determine with increased certainty whether the portable unit is
`located within the predetermined maximal permitted distance from the vehicle.
`
`5
`
`1 0
`
`1 5 According to a second embodiment, at least one of said first signals comprises first
`information that is intended to be utilized for verifying the identity of the portable unit,
`in which the first information is processed by the unit and in which at least one of
`said second signal(s) with verification information comprises a first part with the first
`the
`in
`information part
`first verification
`form. Said
`in processed
`information
`lastmentioned second signal consists suitably of a function of the first information.
`By this means, increased security is obtained with regard to whether it is the correct
`portable unit that has received the first signal.
`
`20
`
`25
`
`According to a further development of the previous embodiment, the lastmentioned
`second signal is sent after the conclusion of the time measurement As the
`processing of the first information in the portable unit takes a certain, not always
`time
`for a
`the conditions are hereby created
`time,
`foreseeable,
`precisely
`
`measurement with high accuracy.
`
`30 According to another embodiment, which is a further development of the previous
`embodiment, at least one of said second signals other than the lastmentioned signal
`comprises second verification information. To sum up, said first signal(s) thereby
`
`TCL Exhibit 1006
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`WO 02/35036
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`
`5
`
`comprise first verification information and said second signal(s), in addition to a
`suitably last of these in time, comprise second verification information. By utilizing
`these first and second signals for said time measurement, the conditions are created
`for achieving a time measurement with high accuracy. The contents in the first and
`the second verification information are suitably independent of each other.
`
`According to a further development of the previous embodiment, the lastmentioned
`second signal comprises, in addition to the first verification information part, also a
`second part that comprises the second verification information in processed form.
`This results in increased security with regard to it being the correct portable unit that
`
`receives said first signals and sends said second signals.
`
`5
`
`1 0
`
`A second aim of the invention is to achieve a specific method for the object for
`controlling authorization to the object with increased security in relation to previous
`
`15
`
`technology.
`
`This aim is achieved by a signal communication via electromagnetic waves being
`established between the object and a wireless portable unit when a tripping device
`arranged on the object is actuated, in which the signal communication comprises at
`least one first signal, that is sent from the object to the portable unit, and at least one
`second signal that is sent from the portable unit in response to said first signal(s)
`after the reception of the first signal and that is received by the object, in which said
`second signal(s) comprise sufficient information for verifying that the portable unit
`has approved identity, and in which the verification information is checked. In order
`to determine the distance between the object and the unit, a time is measured by the
`object from the transmission of one of said first signals until the reception of one of
`said second signals with verification information, the authorization is confirmed if
`both the checked verification information is approved and the measured time is less
`
`than a predetermined value.
`
`20
`
`25
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`30
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`TCL Exhibit 1006
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`WO 02/35036
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`6
`
`A third aim of the invention is to achieve a specific method for a wireless portable
`unit for controlling authorization to an object with increased security in relation to
`
`previous technology.
`
`This aim is achieved by a method intended to be used for controlling authorization
`for access to an object, in which at least one first signal, that was originally sent from
`the object via electromagnetic waves, is received by the portable unit, and in which a
`distance between the object and the portable unit is measured by the unit. At least
`one second signal is sent via electromagnetic waves from the portable unit to the
`object, in which said second signal(s) comprise sufficient information for verifying
`that the portable unit has approved identity, for the distance measurement, a time is
`measured from the transmission of one of said second signals with verification
`information until the reception of one of said first signals, which was sent after the
`reception of said second signal, and a result of the time measurement is sent to the
`object for confirmation of the authorization.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`The invention will be described in greater detail in the following, with reference to the
`embodiments shown in the attached drawings.
`
`Figure 1 shows schematically the object and the portable unit.
`
`Figures 2-5 show in the form of block diagrams the signal communication between
`the object and the portable unit according to four embodiments of the invention.
`
`DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION
`Figure 1 shows schematically an authorization control device 15 comprising an
`object 1 and a wireless portable unit 2. The invention is described below in the case
`in which the object 1 consists of a vehicle. The wireless portable unit 2 is preferably
`sufficiently small to be carried in the user's pocket and is suitably the shape of a card
`
`or a flat object.
`
`5
`
`10
`
`1 5
`
`20
`
`25
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`30
`
`TCL Exhibit 1006
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`

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`WO 02/35036
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`
`7
`
`The vehicle 1 comprises a tripping device 3 in the form of a door handle. Both the
`
`vehicle 1 and the portable unit 2 comprise a transmitter 5, 50 and a receiver 6, 60 for
`
`signal communication via electromagnetic waves. Similarly, both the vehicle 1 and
`
`the portable unit 2 comprise a control unit 7, 70
`
`for controlling the signal
`
`5
`
`communication.
`
`The control unit 7 of the vehicle 1 comprises a memory, which in turn comprises a
`
`program segment, or software components, for controlling at least part of the signal
`
`communication. The control unit 7 is arranged to check information transmitted by
`
`10
`
`the portable unit 2 during the signal communication, to measure the signal time and
`
`to compare the measured signal time with a predetermined value for the purpose of
`
`determining whether the vehicle 1 and the user card 2 are located sufficiently near to
`
`each other during the signal communication. Similarly, the control unit 7 of the
`
`vehicle 1 is arranged to determine at least a part of the information in the signals
`
`1 5
`
`that are to be sent from the vehicle for the identity information control.
`
`The vehicle comprises a lock 11 connected to the control unit 7, which lock is
`
`suitably arranged for locking/unlocking the door of the vehicle to which the door
`
`handle 3 belongs.
`
`20
`
`The control unit 70 of the portable unit is arranged to determine at least a part of the
`
`information in the signals that are to be sent from the unit for the identity control, and
`
`to control identity information sent by the object 1.
`
`25
`
`The information in all signals with identity information that are sent between the
`
`vehicle 1 and the portable unit 2 is encrypted in such a way that the information in a
`
`message transmitted by the object can only be decrypted in its entirety by the
`
`portable unit 2 and vice versa. Such an encryption method is normally called strong
`
`encryption. A so-called asymmetric key pair is used for the decryption function, the
`
`30
`
`control unit of the portable unit holding one of the keys and the control unit of the
`
`object holding the other key. The key of the portable unit 2 comprises identity
`
`information for the portable unit and the key of the vehicle 1 comprises identity
`
`TCL Exhibit 1006
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`WO 02/35036
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`
`8
`
`information for the vehicle. Alternatively, symmetric encryption can be used, which
`means that the vehicle and the portable unit have the same key.
`
`The signal communication between the vehicle 1 and the portable unit 2 according
`to four preferred embodiments of the invention is described below with reference to
`
`5
`
`Figures 2-5.
`
`10
`
`1 5
`
`20
`
`25
`
`Figure 2 illustrates a first embodiment of the signalling method between the vehicle 1
`
`and the portable unit 2.
`
`Signal communication via electromagnetic waves is established between the vehicle
`1 and the portable unit 2 when the door handle 3 is actuated. The control unit 7 of
`the object 1 then creates a message that comprises first information x that is
`intended to be utilized for verifying the identity of the portable unit. The first
`information x consists of identity information O_1D unique to the object and a random
`number O_RND generated by the control unit 7. The message is encrypted and sent
`
`to the portable unit 2 in a first signal X.
`
`The portable unit 2 receives the first signal X and decrypts the message. The
`portable unit 2 processes the first information x and sends a second encrypted
`signal Y1 to the object 1. The second signal Y1 comprises the first information x in
`In
`processed form, more specifically a function f(x) of the first information x.
`particular, f(x) comprises the message part E_SVAR ;:::; f(O_RND). The signal Y1 is
`received by the object 1 and the message is decrypted. A time T1 is measured by
`the control unit 7 of the object 1 from the transmission of the first signal X until the
`reception of the second signal Y1. E_SVAR and T1 are checked by the object 1.
`after which the lock 11 is unlocked if E_SVAR;:::; f(O_RND) and the measured time is
`
`less than a predetermined value.
`
`30
`
`Figure 3 illustrates a second embodiment of the signalling method between the
`vehicle 1 and the portable unit 2, which is a further development of the first
`
`embodiment.
`
`TCL Exhibit 1006
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`WO 02/35036
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`9
`
`According to this second embodiment, two second signals Z, Y2, are sent from the
`portable unit 2 to the object 1 in response to the signal X. A first Z of these second
`encrypted signals comprises second verification information z. The control unit 70
`creates namely a message that consists of identity information E_ID that is unique to
`the unit 2 and a random number E_RND. The second signal Y2 that is last in time
`comprises a first part f(x), as described above, and a second part f(z). In particular,
`f(z) comprises the message part E_ VER = f(E_RND). A time T2 is measured by the
`control unit 7 of the object 1 from the transmission of the first signal X until the
`reception of the first in time Z of said second signals. When Y2 has been received
`and decrypted, f(x) (=E_SVAR), f(z) (=E_ VER) and T2 are checked, after which the
`lock 11 is unlocked if E_SVAR = f(O_RND), E_ VER = f(E_RND) and the measured
`time is less than a predetermined value.
`
`The processing of said first and second information (x and z respectively) is here
`carried out after the time measurement has been completed. Using a suitable
`signalling algorithm, the requisite time from the reception of the first signal X until the
`transmission of the second signal Z can be predicted with high accuracy. For this, a
`signalling algorithm that is highly time-deterministic is required.
`
`Figure 4 illustrates a third embodiment of the signalling method between the vehicle
`1 and the portable unit 2, which is a further development of the second embodiment.
`
`A plurality of first signals Xi are sent from the object 1 to the portable unit 2 and a
`plurality of second signals Zi, Y3 are sent from the portable unit 2 to the object 1.
`The first information x described above is encrypted and the result is divided up into
`a plurality of parts, which are sent in said first signals Xi. The second information z
`described above is encrypted and the result is divided up in the same way into a
`plurality of parts, which are sent in said second signals Zi. The signals X2 .. Xn and
`Z1 .. Zn are sent in series and in such a way that every second signal consists of one
`of said first signals and every second signal consists of one of said second signals.
`A time T3 is measured by the control unit 7 of the object 1 from the transmission of
`
`5
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`1 O
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`1 5
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`TCL Exhibit 1006
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`10
`
`the second in time X2 of said first signals until the reception of the last second signal
`Zn with the second verification information. When all the signals X2-Xn and Z1-Zn
`have been received, the information x and z respectively can be obtained.
`
`5
`
`The last in time second signal Y3 is thereafter produced in the same way as the
`above described Y2.
`
`As an alternative to the first information x being first encrypted and the result
`thereafter being divided up, the information can first be divided up into said plurality
`of parts, after which each of the parts is encrypted. In the same way, the second
`information can, of course, first be divided up into said plurality of parts, after which
`each of the parts is encrypted.
`
`The components of the portable unit 2 used for the signal communication are, for
`example, arranged in a passive state until the tripping device 3 is actuated. When
`the receiver of the portable unit receives the signal X1 from the object following said
`actuation of the tripping device, said components change to an active state. The
`content z in the second signals from the portable unit 2 used for the time
`measurement is now determined. Thereafter the second signal Z1 is sent back to
`the object. Because the time is measured from the transmission of the second in
`time X2 of said first signals, the changeover from passive state to active state is not
`included in the time measurement. This means that the time measurement is carried
`out during a part of the signal communication, the time from the reception of a signal
`until the transmission of a subsequent signal in both the object and the portable unit
`being able to be predicted with high accuracy.
`
`The total time for the part of the signal transmission that is utilized for the time
`measurement can thereby also largely be predicted. By this means, good conditions
`are created for eliminating the risk that the attempted unauthorized access to the
`vehicle described above will succeed.
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`10
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`1 5
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`20
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`TCL Exhibit 1006
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`WO 02/35036
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`11
`
`As the signals are sent in series, any time deviation that occurs for the signal time
`forward and backward between the vehicle and the portable unit is totalled. Such a
`time deviation corresponds to the portable unit, and hence the user, being located at
`a distance greater than a maximal permitted distance from the vehicle. Because of
`said totalling, it is possible to determine more reliably whether the owner of the
`portable unit is located in the vicinity of the vehicle. The more signals that are used
`for the time measurement, the more secure the method. The number of signals from
`the unit that are included in the time measurement is at least one, preferably at least
`two, suitably at least 10 and in particular at least 100. The number of signals that is
`used depends on how high security is desired/required for the authorization control.
`
`The whole message, and hence the content in each of the signals Xi, from the
`vehicle is determined when the tripping device is actuated. In a corresponding way,
`the whole message, and hence the content in each of the signals Zi, from the unit is
`determined when the unit receives the first signal X from the vehicle. By this means,
`the
`the signalling method during the subsequent time measurement, that is
`reception of a signal and transmission of the next signal from both the vehicle and
`the unit, will only consist of a number of well-defined operations. The time required
`for this method can thereby be predicted with high accuracy.
`
`When the control unit 70 of the portable unit 2 has sent the last signal with said
`identity information part to the vehicle, it decrypts the total message from the vehicle
`using its encryption key. The decrypted message x has two parts, namely 0_10 and
`O_RND. The portable unit 2 thereafter sends the last signal Y3 to the vehicle with
`information that it has received the whole message and succeeded in decrypting it,
`which is verified by the number O_RND being included in the signal. More
`specifically, the message part is created E_SVAR = f(O_RND). The last signal Y3
`from the portable unit also comprises the message part E_RND. More specifically,
`E_ VER= f(E_RND) is created for the lastmentioned message part.
`
`When the control unit 7 of the vehicle 1 has received for the time measurement the
`last Zn of said second signals with said identity information part from the portable
`
`5
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`1 O
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`1 5
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`20
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`25
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`30
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`12
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`unit 2, it decrypts the message using its encryption key. The decrypted message f(z)
`
`has two parts, namely E_ID and E_RND. Authorization is confirmed after the control
`
`unit 7 of the vehicle 1 has received the last signal Y3 from the portable unit 2,
`
`provided that:
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`5
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`0
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`•
`•
`•
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`E_ID is an approved key,
`
`E_SVAR = f(O_RND),
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`E_ VER= f(E_RND), and
`
`the measured time is less than or equal to a predetermined value that
`
`corresponds to a maximal permitted distance between the portable unit and
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`10
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`the object.
`
`Figure 5 illustrates a fourth embodiment of the signalling method between the
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`vehicle 1 and the portable unit 2, which is a variant of the third embodiment and
`
`differs from this in that a signal transmission time T 4 is measured by the control
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`1 5
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`unit 70 of the unit 2. A signal Y 4 also comprises a result of this time
`
`measurement, in addition to the information in said signal Y3.
`
`Both the control unit 7 of the object 1 and the control unit 70 of the portable unit
`
`2 comprise a memory, which in turn comprises a computer program product
`
`20 with program segments or a program code, for carrying out all
`
`the steps
`
`according to any one of the embodiments described above when the program is
`
`executed. The computer program product can be transmitted to the object or the
`
`portable unit
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`in various ways via a propagating signal,
`
`for example via
`
`downloading from another computer, via cable and/or wireless means, or by the
`
`25
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`installation of a memory circuit. In particular, the propagating signal can be
`
`transmitted via the Internet. The term computer unit used in the claims refers to
`
`said control unit.
`
`When the authorization is confirmed, an unlocking signal is sent from the
`
`30
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`vehicle's control unit to a lock on a door of the vehicle, which is thereby
`
`unlocked automatically.
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`TCL Exhibit 1006
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`13
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`The predetermined time value that corresponds to a maximal permitted distance
`between the portable unit and the object depends, of course, on the number of
`signals that are included in the time measurement.
`
`5 The embodiments described are only to be regarded as preferred examples and a
`number of further variants and modifications are possible within the scope of the
`following claims. For example, the portable unit can be programmed to determine
`the information in the message in its entirety before it receives the first signal from
`the object.
`
`10
`
`15
`
`The invention is in particular intended for electromagnetic waves in the form of radio
`waves or microwaves. The frequency range or frequency ranges of the waves are
`preferably selected within a range where they are not subject to inference from other
`strong signals.
`
`It is, of course, within the scope of the following claims to send signals without
`identity information between, before and/or after the signals with the identity
`information during the time measurement.
`
`20 The number of signals that are to be sent from the portable unit for the identity
`control and/or the time measurement can, of course, be determined by the control
`unit 70.
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`25
`
`It is, of course, also possible to vary the content in the signals used for the
`transmission of the identity information, while remaining within the scope of the
`claims.
`
`30
`
`The invention described above is, of course, not limited in any way to application to
`a vehicle, but could, for example, be used for controlling authorization for access to
`a stationary object, such as a building, a room or part of a building. The invention is
`similarly applicable to factory premises or an enclosed area, for example bounded
`by a fence, railings or the like. Nor is the invention restricted to the unlocking of a
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`14
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`previously locked lock, but could of course also be used for locking a previously
`unlocked lock.
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`In addition, instead of a door handle, the tripping device 3 can also consist of an
`optic