FR2807238A1 - Remote control, for motor vehicle starter function, has multiple antennae which emit control signals received by transponder which allows operation of starting function - Google Patents

Abstract

Remote control has multiple antennae (48A-F) each emitting control signal and interrogation signal across associated area of vehicle. Control circuit (34) controls antennae to sequentially emit control signals. Transponder (44) emits response signal when in required area and control circuit determines which antenna is operational to allow operation of vehicle function when transponder responds to interrogation signal.

Description

The present invention relates to passive remote control systems, and specifically relates to systems that include a multiplicity of interrogation antennas.

knows passive remote control systems for vehicles. An example of a passive remote control system is a passive motor starter system for a vehicle. An authorized person (eg a vehicle owner) carries a portable transmitter or transponder. When the authorized person is inside the associated vehicle, a transceiver or transponder based in the vehicle interrogates the portable transponder. In response to the interrogation, the portable transponder transmits a signal that transmits a security code identification.

 transponder based in the vehicle determines whether the provided identification is authentic. If the correct identification is provided, an ignition component for the vehicle engine is activated without the person manually turning a key in an ignition switch, manually entering a code on a vehicle keypad, or the like. Therefore, the authorized person simply operates a push button or a start contact to start the engine.

Another type exemplifying a passive remote control system for a vehicle is a passive system for entry into a vehicle. Such a system allows automatic unlocking of a door of a vehicle, or the like, for an authorized person wishing to enter a vehicle. Specifically, the authorized person does not need to manually turn a key in a vehicle lock, manually operate a handheld transmitter, or manually enter a code on a vehicle keypad.

Similar to the passive motor starter system, the passive input system includes a transceiver or identification transponder carried on the authorized person, and a transceiver or basic transponder placed in the vehicle. The vehicle-based transponder interrogates the portable transponder and, in response to the interrogation, the portable transponder transmits a signal that transmits a security code identification. In response to the reception signal transmitting the authentic security code the transceiver based in the vehicle unlocks the vehicle door. The authorized person can therefore simply operate a door handle and open the door.

Some known passive vehicle remote control systems are commonly referred to as contactless identification and authentication systems. Some known passive vehicle remote control systems have used radio frequency (RF) communication between a portable transponder and a vehicle-based transponder. Such systems are often called RF identification systems.

In a vehicle passive remote control system, it is typically desirable that the authorized person be in close proximity to the appearance of the vehicle is remotely controlled. For example, for a passive entry system for a vehicle, the authorized person must be relatively close to the associated vehicle before a vehicle door is unlocked. The fact that the authorized person is in the immediate vicinity of the vehicle when the vehicle door is unlocked will help reduce the possibility that an authorized person may not be aware that a door of the vehicle has been passively unlocked.

For a passive vehicle remote control system that uses RF communication, precise range control is difficult to achieve because of the potential for signal reflection and multipath propagation. In addition, RF communication field strengths decrease as a function of the inverse of the square of the distance from the emission source.

Communication between a basic transceiver and a portable transceiver must comply with the regulations regarding the maximum frequency and maximum transmitted signal level. In the United States the Federal Communications Commission ("FCC") imposes such regulations. In the United States, remote control communication for passive and similar input systems typically takes place in the RF spectrum portion that is allocated by the for non-license transmitting devices. Typically, the exchange of communications takes place in the ultra-high frequency portion of the RF spectrum.

Those skilled in the art will appreciate that noise may be present in the RF spectrum. Interference (eg RF interference) caused by noise can have a detrimental effect on some communication systems. The scrambling level can be up to the level of interruption of communication. It is possible that some types of passive remote control systems may be adversely affected by interference. The result would be that the authorized person would not have the convenience of the passive remote control of the vehicle function. For example, in a passive entry system, the authorized person would not have the convenience of passive entry (for example, the authorized person should turn a key in a lock, manually enter a code on a keyboard, or other ).

In a known system, the use of multiple antennas provides coverage for multiple areas. Specifically, the multiple antennas provide increased interrogation coverage for signals from a vehicle-based transponder structure, and increased reception coverage for a signal transmitted by a portable transponder. This leads to a concept that coverage must be established for areas within which a portable transponder may be at a time when an authorized operator is waiting for a remotely operated vehicle function to be performed.

In an example of a passive motor starter system, it is possible for a portable transponder to be at any one of several locations inside a vehicle when the operator wishes to start the vehicle engine. For example, the portable transponder may be placed inside a coat or purse of the authorized person, and the coat or purse may be placed in the rear seat of the vehicle. An antenna of a vehicle-based transponder structure that has zone interrogation / reception limited to a region around a driver's seat may be unable to communicate with a portable transponder placed in the rear seat area. If multiple antennas of a vehicle-based transponder structure are used to provide coverage for multiple areas, it is possible for interrogation / reception coverage areas to overlap. If coverage areas overlap, it is possible that coincidence interrogation signals from two or more antennas on a vehicle collide. Therefore, it is advantageous to limit each interrogation attempt to only one antenna at a time.

It is possible to sequentially enable each of a plurality of antennas of a vehicle-based transponder structure to attempt to interrogate a portable transponder. It will be appreciated, however, that the time required to allow multiple antennas to sequentially attempt an interrogation is related to the number of antennas in the vehicle-based transponder structure.

In one aspect, the present invention provides a system for remotely controlling a function of a vehicle. The system comprises a multiplicity of interrogation means. Each interrogation means may be actuated to transmit an interrogation signal through a region of the vehicle associated with a respective one of the interrogation means. The system includes portable identification means for receiving the interrogation signals. The portable identification means transmits a response signal transmitting an identification, in response to receiving one of the interrogation signals. A means receives the response signal and performs the function of the vehicle in response to receiving the response signal A means determines in which region of the vehicle is the portable means and actuates the associated interrogation means to transmit the interrogation signal .

In another aspect, the present invention provides a system for remotely controlling a function of a vehicle. The system comprises a multiplicity of interrogation means. Each interrogation means may be actuated to transmit an interrogation signal in a region of the vehicle associated with a respective one of the interrogation means. The system includes portable identification means for receiving one of the interrogation signals. The portable identification means transmits a response signal that transmits an identification, in response to the reception of the interrogation signal. A means receives the response signal and performs the function of the vehicle in response to receiving the response signal. Before transmitting any of the interrogation signals, means determines which interrogation means must operate to transmit its interrogation signal, so that the interrogated interrogation signal is received by means of portable identification. . In another aspect, the present invention provides a system for remotely controlling a function of a vehicle. The system comprises a multiplicity of interrogation means. Each interrogation means may be actuated to transmit an interrogation signal. Each interrogation signal may be received within a region of the vehicle associated with a respective one of the interrogation means. The system includes portable identification means for receiving one of the interrogation signals when the identification means is placed within the respective associated region, and the respective interrogating means transmits the interrogation signal. The portable identification means transmits a response signal that transmits an identification in response to the reception of the interrogation signal. A means receives the response signal and performs the function of the response vehicle upon receipt of the response signal. A means determines which of the plurality of interrogation means is to be operated to provide the interrogation signal for reception by the identification means, and operates the interrogation means under consideration to transmit the interrogation signal.

In another aspect, the present invention provides a system for remote control of a vehicle function. The system includes a multiplicity of antennas. Each antenna can be operated to transmit a request signal and an interrogation signal through an associated region of the vehicle. The system includes a transponder for receiving the request signals and for transmitting a first response signal that transmits presence indication, in response to receiving one of the request signals. The transponder receives the interrogation signals and transmits a second response signal transmitting an identification in response to receiving one of the interrogation signals. A control unit causes the request signals to be transmitted in one sequence. The control unit determines which antenna is associated with a situation in which the transponder transmits first response signal. The control unit causes the determined antenna to transmit its interrogation signal and performs the function of the vehicle in response to the transmission by the transponder of the second response signal, under the effect of the reception of the signal of the signal. interrogation issued.

In yet another aspect, the present invention provides a transponder for a system that remote controls a function of a vehicle. The transponder includes means for receiving any of a plurality of request signals that are transmitted in respective regions of the vehicle. Means emit a first response signal transmitting an indication of presence for a respective region, in response to receiving one of the request signals. Means receive any of a plurality of interrogation signals which are transmitted in respective regions of the interior of a vehicle.

Means transmit a second response signal transmitting an identification in response to the reception of the interrogation signal associated with the respective region.

In yet another aspect, the present invention provides a method for remotely controlling a vehicle function. There is a multiplicity of interrogation means. Each interrogation means may be actuated to transmit a signal through a region of a vehicle associated with a respective one of the interrogation means. It is determined in which region of the vehicle a portable identification means is placed. The associated interrogation means is actuated to transmit an interrogation signal. The interrogation signal is received by means of portable identification. The portable identification means transmits a response signal that transmits an identification in response to the reception of the interrogation signal. The response signal is received. The function of the vehicle is accomplished in response to receiving the response signal.

In yet another additional aspect, the present invention provides a method for remotely controlling a function of a vehicle. A plurality of request signals are transmitted in one sequence to associated regions in the vehicle. A request signal is received at a transponder placed in one of the associated regions. transponder transmits a first response signal which transmits an indication of presence in response to the reception signal request. The region in which the transponder is located is determined using the first response signal. An interrogation signal which is associated with the region in which the transponder is located is transmitted. The interrogation signal is received at the transponder. The transponder transmits a second response signal that transmits an identification in response to the reception of the interrogation signal. The function of the vehicle is accomplished in response to the transmission of the second transponder response signal.

Other features and advantages of the invention will be better understood on reading the following description of embodiments, given by way of non-limiting examples. The following description refers to the accompanying drawings, in which Figure 1 is a schematic illustration of a first embodiment of a system according to the present invention and shown with a vehicle associated Figure 2 is a functional block diagram of a control unit shown in Figure 1; Fig. 3 is a flowchart for a process performed in the control unit shown in Fig. 2; Fig. 4 is a functional block diagram of an identification transponder; Fig. 5 is a process flow chart in the identification transponder shown in Fig. 4; Fig. 6 is a schematic illustration of a second embodiment of a system according to the present invention and shown with an associated vehicle; Fig. 7 is a schematic illustration of a third embodiment of a system according to the present invention and shown with an associated part of a vehicle; and Fig. 8 is a schematic illustration showing a functional aspect of a system according to the present invention.

A system 10 for remote control of a function of a vehicle according to the present invention and associated vehicle 12 are shown in FIG. 1. The vehicle 12 comprises a motor 14 (for example an internal combustion engine). The vehicle 12 also includes a vehicle interior (eg a passenger compartment) in which a user (not shown) is located when the user is operating the vehicle. In the example shown in Figure 1, the interior 16 of the vehicle has a front seating area 18 in which there is a driver seat 20 and a front passenger seat 22. The interior 16 also includes rear seat area 24 In which is a rear seat In the example shown in Figure 1, the function that is remotely controlled by means of the system 10 is a function of ignition authorization or simply a start function of the engine. The system 10 includes a start control component 28 which provides an authorization signal 30 to a suitable component (e.g., ignition of the engine) of the engine 14 of the vehicle that allows the engine to start. In addition, the authorization function for starting the engine 14 of the vehicle is passive for the operator who is an authorized person. Specifically, the authorization of the engine start-up 14 vehicle is accomplished without the need for the authorized person to perform an activity indicates' authority of the person.

The authorized person does not need to introduce turning a key into a key lock or enter a security code on a code entry device. At most, the authorized person must only request the start of the engine 14. Such a start request function is performed in the illustrated example a start request entry device 32. An example of a request entry device of start 32 a push-button or switch device that is manually operated when the authorized person is on the driver's seat 20 and the person is ready for starting the engine 14 of the vehicle.

A control unit 34 of the system 10 is operably connected at 36 to the start control component 28 and is operably connected at 38 to the start request input device 32. When the authorized person enters a start request into the device start request entry, the control unit 34 determines whether it is indicated that authorized person is present or not. If the determination is affirmative (ie if it is indicated that authorized person is present), then ignition is allowed and engine start 14 takes place.

The control unit 34 is part of a vehicle-based transponder structure 42 which communicates with an identification transponder 44 which is associated with an authorized person to determine the presence and authenticity of the identification transponder. The presence of the identification transponder 44 and the provision of an appropriate identity to the vehicle-based transponder structure, 42, indicate that the authorized person is present. The identification transponder 44 may take the form of a badge, button, tag or charm that an authorized person wears in a pocket of a garment in his wallet, or attached to his door. or another personal item. The identification transponder 44 is therefore a portable transceiver which is worn by the authorized person. In what follows, the identification transponder 44 is simply called the transponder ID 44. passing to the transponder structure based in the vehicle, 42, we note that this structure comprises a multiplicity of magnetic antennas (eg 48A 48F). Each magnetic antenna (for example 48A) is placed at a predefined position (for example door) of the vehicle 12 and emits magnetic signals (for example 50A) which propagate in a certain associated region (for example a part of the seating area before 18) of the interior 16 of the vehicle. Preferably, each magnetic antenna (eg 48A) is a short cylindrical coil that can be electrically energized to produce a field pattern of the associated output signals (eg 50A). In one example, the field configuration has a toroidal field configuration. Magnetic signals are preferably emitted at a low frequency ("BF") are hereinafter called BF signals.

In the example shown in FIG. 1, six magnetic antennas 48A-48F are placed in the vehicle 12. A first magnetic antenna 48A is placed inside a passenger-side front door 52, and sends BF signals 50A. which propagates in a region of the vehicle which includes the front passenger seat 22. A second magnetic antenna 48B is placed inside a passenger-side rear door 54 and transmits BF signals 50B propagating in a region of the vehicle which includes a first lateral portion of the rear seat area 24. A third magnetic antenna is placed in or near a rear deck area 56 of the vehicle 12 and transmits 50C signals propagating in a region of the vehicle which comprises a central part of the rear seat area A fourth magnetic antenna 48D is placed inside a rear door on the driver's side 58 and emits BF 50D signals propagating in a region of the vehicle which includes a second side portion of the rear seat area 24. A fifth magnetic antenna 48E is placed inside a front door on the driver's side 60 and transmits BF signals 50E propagating in a region of the vehicle which includes the driver's seat, 20. A sixth magnetic antenna 48F is placed inside a rearview mirror 62 of the vehicle 12 and transmits BF signals 50F propagating in a central portion of the vehicle. front seating area 18.

The signals BF 50A-50F emitted by the first to sixth magnetic antennas 48A-48F are intended to be received by the ID transponder 44. A signal BF (for example 50A) is received by the ID transponder 44 when the transponder ID is within the associated region in which the BF signal is propagated. BF signals are thus a first aspect of communication between the vehicle-based transponder structure and ID transponder 44. Each of the first to sixth magnetic antennas 48A-48F is operatively connected at 66A-66F to the unit. 34, and the control unit controls the magnetic antennas to transmit the BF signals 50A - 50F. Therefore, magnetic antennas 48A-48F are energized to transmit their respective RF signals 50A-50F in response to electrical excitation signals provided by the control unit 34. As a second aspect of the communication between the transponder structure based on in the vehicle,, and ID transponder 44, the ID transponder transmits signals 68 and the vehicle-based transponder system includes an antenna 70 for receiving signals from the ID transponder. The antenna 70 is operatively connected at 72 to the control unit 34. In the preferred embodiment, the signals 68 from the ID transponder 44 and directed to the vehicle-based transponder structure, 42, are radio frequency ("RF") signals. The signals 68 are therefore called the RF signals. The RF signals 68 are received at the antenna 70 regardless of the location of the ID transponder 44 in the interior 16 of the vehicle.

By passing to the signals BF 50A - 50F which are emitted by magnetic antennas 48A - 48F, it is noted that a type of signal BF emitted by each magnetic antenna is a interrogation signal which is intended to be received by the ID transponder. 44. Under the effect of the reception of an interrogation signal, the transponder of ID 44 emits a type of RF signal 68 which is a request for authorization to ignite the engine. The authorization request signal transmits an appropriate security code, which identifies the ID transponder 44 and therefore identifies the ID transponder carrier as the person who is authorized to start the engine 14 of the vehicle 12.

In response to receiving the RF authorization request signal, the control unit 34 of the vehicle based transponder structure, 42, verifies the provided security code identification. If the verification of the identification is positive, the control unit 34 causes the start-up control component 28 to enable the ignition of the motor 14. Therefore, the authorized person must only operate the input device of start request 32 (eg actuate a push button) to start the engine 14 of the vehicle 12. Therefore, again, it must be realized that the authorized person does not need to manually turn a key in a ignition lock, manually operate a hand-held transmitter, or manually enter a code on a keypad in the vehicle, or others. In general terms, the vehicle-based transponder structure, 42, and the ID transponder 44 are in a communication configuration for performing an automatic ignition interrogation and authorization sequence for the authorized person.

It will be appreciated that the continuous transmission of some or all of the BF signals 50A-50F from the magnetic antennas 48A-48F would simply consume excessive amounts of electrical energy (e.g., consumption on the vehicle battery). Specifically, it is only when the engine 14 of the vehicle is about to be started that it is necessary for communication to take place between the vehicle-based transponder structure, 42, and the transponder. ID 44. Therefore, an appropriate triggering means can be used to begin the communication. For example, manual operation of the start request input device 32 could be used to trigger the communication. Other possibilities for triggering include detecting the opening of a vehicle door (eg 60).

In addition, it will be appreciated that the ID transponder 44 will transmit the RF authorization request signal only if the ID transponder is within the associated region through which a BF interrogation signal is propagating. The transmission of an RF interrogation signal and the waiting for a possible RF authorization request signal as a response require a certain amount of time. Specifically, a complete RF interrogation signal must be received by the ID transponder 44, and then a complete RF authorization request signal must be issued by the ID transponder. The control unit 34 must wait a certain time for a possible RF authorization request signal response.

It will be appreciated, therefore, that the sequential activation of the magnetic antennas 48A-48F to sequentially produce respective RF interrogation signals, and the expectation of an RF authorization request response possible (for example, it is not known initially whether the ID transponder 44 is placed within the associated region in which the interrogation signal extends) would take a long time. Although as will be appreciated, such sequential operation would ultimately "find" the ID transponder 44 located in the interior of the vehicle, the delay that could be associated with such a sequence of complete interrogation signals could lead to Bene for authorized person. Typically, it is desirable for a vehicle engine to start almost immediately when ignition of the engine is requested.

It will be appreciated that the regions through which the BF 50A-50F signals from the respective magnetic antennas 48A-48F extend may overlap.

for example, FIG. 1 illustrates a notable overlap of signal regions for the first and sixth magnetic antennas 48A and 48F, the second and third magnetic antennas 48B and 48C, the third and fourth magnetic antennas 48C and 48D, and the fifth and sixth antennas magnetic 48E and 48F. Further, it will be appreciated that there is a possibility that some form of interference may occur if the BF-50F signals are emitted simultaneously from magnetic antennas that overlap signal regions.

When the ID transponder 44 is in the interior of the vehicle, the ID transponder will be placed within the signal region associated with one or more of the plurality of magnetic antennas (eg, 48A). Note, however, that initially the vehicle-based transponder structure, 42, does not "know" the signal region (s) in which the ID 44 transponder is located. In addition, because of the possibility of interference between BF signals 50A - 50F which have overlapping regions, it would be imprudent to operate simultaneously all the magnetic antennas 48A -. 48F to transmit their associated RF interrogation signals.

Therefore, in accordance with the present invention, the control unit 34 of the vehicle-based transponder structure, 42, causes magnetic antennas 48A-48F to transmit relatively short duration RF request signals, as than other forms of BF signals 50A - 50F. The request signals BF appear before an interrogation signal BF. Receiving an RF request signal from the ID transponder 44 causes the ID transponder to provide an RF request response signal which simply indicates the presence of the ID transponder in an associated region in the ID transponder. inside 16 of the vehicle. For example, the demand signal BF is a short duration CW pulse and the RF demand response signal from the ID transponder 44 is a short duration RF pulse. The RF request response signal is another form of the RF signals 68, and is a first RF signal that is transmitted by the ID transponder 44.

In one embodiment, the control unit 34 sequentially energizes the magnetic antennas 48A-48F so that each magnetic antenna sequentially emits the associated BF request signal to propagate through the associated region of the interior 16 of the antenna. vehicle. As shown in the example of Fig. 1, only the request signal BF from the first magnetic antenna 48A is transmitted at the present time, and the other request signals BF (which are drawn in dotted lines) are transmitted in time intervals. different. When the ID transponder 44 responds to a request signal BF with a request response signal BF, the control unit 34 identifies the magnetic antenna (eg 48A) which transmits the request signal BF which caused the request. RF request response signal.

It will be appreciated that in another embodiment, a data exchange takes place during the "request signal / request response signal" sequence. For example, the demand signal BF from each magnetic antenna (eg 48A) transmits data as a stimulus, instead of simply relying on the existence of the demand signal BF in the form of a sustained wave, as a stimulus. The data may include a vehicle identification, which is used to avoid an unnecessary request response signal from an ID transponder of a different system.

In accordance with the present invention, the identified magnetic antenna (e.g., 48A) is used to transmit a complete BF interrogation signal. Since the response to the request signal BF indicates that the ID transponder 44 will receive BF signals from the identified magnetic antenna (eg 48A), the interrogation signal BF is received by the ID transponder. In turn, the ID transponder 44 provides the RF antenna 70 / control unit 34 with the authorization request signal (e.g., security code identification) as a second signal. After verifying the identification transmitted by means of the authorization request signal, the control unit 34 authorizes the ignition of the engine, as envisaged above.

FIG. 2 illustrates portions of the control unit 34 which sequentially transmit the one or more demand signals BF from the antenna or the magnetic antennas (BF) 48A - 48F, and the transmission of a BF interrogation signal from the selected magnetic antenna. A signal from the start request input device 32 is applied to the RF receive circuit 74 as a wake command to allow the RF receive circuit to receive RF signals (i.e. a request response and a request for authorization) from the ID transponder 44. The start request input signal from the input device 32 is also applied to a magnetic antenna sequencer (ie ie BF) 76.

Antenna sequencer 76 is operatively connected at 78 to a BF 80 antenna driving control section 80. The excitation control section 80 includes a BF transmit circuit for driving magnetic antennas 48A-48F. In response to certain control signals from the antenna sequencer 76, the excitation control section 80 sequentially outputs to the magnetic antennas 48A-48F electrical stimulus signals under which the magnetic antennas sequentially transmit the signal signals. respective BF application.

The antenna sequencer 76 and the excitation control section 80 progress among the antennas (for example from the first antenna to the antenna N, ie the sixth antenna in the example described), until a The request response signal is received from the ID transponder 44. To terminate the sequential progression, the control unit 34 includes an antenna selection section 82 which is operatively connected at 84 to the antenna sequencer 76. and is operably connected at 86 to the RF receiving circuit. The antenna sequencer 76 indicates to the antenna selection section 82 which magnetic antenna (e.g., 48A) is currently energized to transmit a request signal BF, and the RF receiving circuit 74 provides a indication to the antenna selection section when an RF request response signal is received. When an RF request response signal received, the antenna selection section 82 determines that the magnetic antenna present (e.g., 48A) is energized to transmit the request signal BF is the antenna to be used for the sequence complete interrogation (that is, the present antenna is selected). Therefore, the antenna selection section 82 controls the antenna sequencer 76 to stop sequentially exciting antennas to transmit request signals. In addition, the antenna selection section 82 indicates the selected magnetic antenna (eg 48A) to a full interrogation communication section 88 which is operably connected at 90 to the antenna selection section.

The complete polling communication section 88 is operatively connected at 92 to the excitation control section 80. On receiving the selected antenna information, the complete polling communication section 88 provides the polling section 80 with the information. excitation control 80 a signal which transmits an interrogation command, together with the information indicating the selected antenna. In turn, the excitation control section 80 controls the interrogation signal transmission only by the selected magnetic antenna (eg 48A).

In response to the interrogation signal, the ID transponder 44 (FIG. 1) provides a complete interrogation response (i.e. identification) that is received at the RF antenna 70 and is transmitted to the RFID circuit. RF reception 74 (Figure 2). In turn, the information transmitted by means of the interrogation response signal is provided to a full response processing section 94 which is operatively connected at 96 to the RF receive circuit 74. In the full response processing section 94 , the content of the authorization request signal is decoded and the supplied identification security code verified by comparison with a security code from a memory 98 of the control unit 34. If the verification of the identification is positive, full response processing section 94 provides a suitable signal to the boot control component 28.

Fig. 3 shows a flowchart for a process 100 which is performed in the control unit 34 in Fig. 2. The process 100 (Fig. 3) is started in step 102 and proceeds to step 104. At step 104, it is determined whether a start request or ignition from the start request input device 32 has been received. If the determination at step 104 negative (i.e., a start request has not yet been received), the process 100 loops to repeat the interrogation of step 104. If the determination step 104 is affirmative (i.e., a start request has been received), process 100 proceeds to step At step 106, a variable N is set equal to 1. N an identifier of an antenna that must be excited present moment. At step 108, the magnetic antenna N is energized in a short CW pulse to produce the request signal. In step 110, it is determined whether an RF request response signal is received. If the determination at step 110 is affirmative (i.e. a request response is received, indicating that the transponder of 44 is within the associated region for the excited antenna) the process 100 proceeds to step 112. In step 112, a complete interrogation signal is transmitted by the N antenna (i.e., N is the selected antenna). In step 114, the processed authorization request signal and the ignition authorization is controlled (if ID 44 transponder identification has been successfully verified). Upon completion of step 114, the process loops back to step 104. If the determination in step 110 is negative (i.e. a request response is not received, then which indicates that the ID transponder 44 is not in a region associated with the excited antenna), the process 100 proceeds to step 116. In step 116, it is determined whether all the 48A-48F antennas have were excited sequentially to produce their associated BF request signal. If the determination at step 116 is negative (i.e. all antennas have not yet been sequentially excited), process 100 proceeds to step 118. At step 118, variable N is increased by one. Therefore, increasing the variable causes the next sequential antenna to be selected. Upon completion of step 118, the process 100 proceeds to step 108 at which the newly selected N-antenna is energized to transmit the interrogation signal.

If the determination at step 116 is affirmative (ie, all the antennas 48A-48F have been sequentially energized to transmit their respective RF request signals), then the control unit 34 deduces that the transponder ID 44 is not in the interior 16 of the vehicle 12, or at least not in a region associated with one of the magnetic antennas 48A 48F. In the case of the affirmative determination in step 116 (i.e., all antennas 48A-48F have been tried without response to any request signal), process 100 goes from step 116 to step 104. Therefore, the authorized person must bring the ID transponder 44 into one of the signal regions for the magnetic antennas 48A-48F, and operate the start request input device 32.

It is envisaged that some form of notification could be provided to the occupant of the vehicle, to indicate that the vehicle-based transponder system attempted to locate the ID 44 transponder, but was unable to do so. The indication will require placing the ID transponder 44 at a location at which the ID transponder can be "found" at the time of subsequent sequential excitation of the antennas 48A-48F.

Turning to Figure 4, we see the structure of the ID transponder 44 which allows the ID transponder to first provide a request response and then a complete interrogation response. An (magnetic) BF antenna 124 is operatively connected at 126 to a BF receive circuit 128. In turn, the BF receive circuitry 128 is operatively connected at 130 to a request processing section 132, and is operably connected at a plurality of times. to an interrogation processing section 136. The request processing section 132 is functionally connected at 138 to an RF transmitting circuit 140. In addition, the interrogation processing section 136 is functionally connected at 142 to the circuit. RF emission 140.

When the BF antenna 124 / BF receive circuit 128 receives the CW pulse that indicates a request signal, the BF receive circuit 128 applies an excitation signal to the request processing portion 132. In response, the request processing section 132 transmits a short response excitation signal to the RF transmitting circuit 140. In turn, the RF transmission circuit 140 excites an RF antenna 144 which is operatively connected to the RF transmitter circuit 140. to the RF transmission circuit, and causes the RF antenna to transmit the request response signal.

In the exemplary embodiment, a timer 148 is operatively connected to the request processing section 132 and is also operatively connected at 152 to the interrogation processing section 136. The timer 148 is triggered when the request processing section 132 is working on a received request signal BF, for measuring a time interval during which the interrogation processing section 136 must wait for the interrogation signal. It will be appreciated that timer 148 and its function may be omitted.

When the BF antenna 124 / BF receive circuit 128 receives the interrogation signal, the information contained therein is supplied to the interrogation processing section 136. The interrogation processing section 136 accesses an identification security code in a memory 154 and provides the identification in an encrypted message to the RF transmission circuit 140. In turn, the RF antenna 144 is energized to transmit the authorization request signal which transmits the identification. .

Turning to FIG. 5, there is shown a process 160 that is performed in the ID transponder 44 of FIG. 4. The process 160 (FIG. 5) is started at step 162 and proceeds to step 164. A step 164, it is determined whether a request signal BF (i.e., the short pulse in the form of a sustained wave) is received. If the determination in step 164 is negative (i.e. ID transponder 44 is still waiting for a request signal), process 160 loops to repeat step 164. If step 164 is affirmative (i.e., a request signal is received), the process 160 proceeds to the step. In step 166, the RF request short response signal is transmitted by the ID 144 transponder.

In step 168, it is determined whether an interrogation signal BF is received. If the determination in step 168 is affirmative (i.e. the interrogation signal is received), the process 160 proceeds to step 170 at which the authorization request signal (that is, the interrogation signal is received). - ie the identification) is issued. Upon completion of step 170, the process 160 loops to step 164 to wait for another request signal.

If the determination at step 168 is negative (i.e. ID transponder 44 is still waiting for the interrogation signal after receiving the request signal), the process 160 passes. from step 168 to step 172. In step 172, it is determined whether a predetermined time interval during which the ID transponder 44 waits for the interrogation signal has flowed. If the determination in step 172 is negative (i.e. the time interval has not yet elapsed), the process 160 goes from step 172 to step 168 to ask again if the interrogation signal BF is received. However, if the determination in step 172 is affirmative (i.e., the time interval has elapsed), the ID 44 transponder assumes that it is no longer appropriate to wait. an interrogation signal and goes from step 172 to step 164. Therefore, the ID transponder waits for another request signal.

Although it is possible that the regions inside a vehicle through which the RF signals propagate may overlap and thus cause a possibility of interference, it is envisaged that the signals coming from certain antennas are unlikely. to overlap / scramble. Consequently, the embodiment of the system 210 shown in FIG. 6 is a variant of the embodiment of FIG. 1 but performs simultaneous emission of RF signals from a multiplicity of magnetic antennas. The system 210 shown in FIG. 6 has many components that are identical to the corresponding components shown in FIG. 1. Identical reference numbers are used to identify identical components. The system 210 of FIG. 6 differs from the system 10 of FIG. 1 in that the vehicle-based transponder structure 242 shown in FIG. 6 does not sequentially produce BF request signals transmitted by the magnetic antennas 48A. Specifically, the control unit 234 controls the antennas 48A-48F so that a plurality of request signals BF are transmitted simultaneously.

In one example, two magnetic antennas are energized simultaneously to transmit their respective request signals. Figure 6 shows the first and fourth magnetic antennas 48A and 48D (identified in the figure as "ACTIVE") excited simultaneously to transmit their respective RF request signals. Other pairs of antennas (e.g. the second fifth magnetic antennas 48A and 48E, and the third and sixth magnetic antennas 48C and 48F) are sequentially excited simultaneously.

simultaneous excitation of a multiplicity of magnetic antennas allows a faster progression in the transmission of demand signals by the antennas, thus a faster location of the ID transponder by the transponder structure based in the vehicle 242. In addition, it is contemplated that the request signals from the magnetic antennas can transmit an antenna identification, and that the ID transponder can provide the interrogation response signal with an indication of which of the multiple excited response antennas. For example, the BF request signal transmitted by each antenna may be specific in a certain respect, and the specific aspect may be repeated or imitated in return for the vehicle-based transponder structure, 242, from transponder of ID 44.

Moreover, it is envisaged that a specific identification among active magnetic antennas at the present time may not be necessary. it is considered possible to excite the same group of antennas (for example first and fourth magnetic antennas and 48D) so as to emit their respective interrogation signals BF if the ID transponder 44 is placed inside one of them. or one of the associated regions of the vehicle. By way of FIG. 7, an embodiment is shown which provides the passive remote control of another function of a vehicle (that is to say a function other than ignition of the vehicle). Specifically, a system 310 of the embodiment shown in FIG. 7 allows passive entry into a vehicle 312. A door 318 closes an interior 316 of the vehicle 312. The door 318 is therefore an entry barrier for an entrance passage in the interior 316 of the vehicle. A door lock mechanism (not shown) locks the door 318 in a closed position and a door handle 320 can be manually operated to operate the lock mechanism and open the door.

A door lock 322 prevents actuation of the locking mechanism. Therefore, the door lock 322 is an access control component that controls access to the interior 316 of the vehicle. The system 310 controls the door lock 322. Thus, an authorized person (not shown) does not need to insert and turn a key in a lock or enter a security code on a code entry device, or similar. At most, the authorized person must simply advance towards the door handle 320 and actuate it.

A sensor 324 of the system 310 is placed adjacent to the door handle 320 to detect when a hand (not shown) is advancing toward the handle. A control unit 328 of the system 310 is operatively connected at 330 to the sensor 324. When the sensor 324 detects the hand advancing toward the handle 320, the control unit 328 operates to determine whether it should allow entry into the interior of the vehicle. If the determination is affirmative (that is, the person advancing toward the door handle is an authorized person), then the door 318 is unlocked. Specifically, a signal is applied to a lock control member 332 which is operatively connected to the control unit 328. In turn, the lock control member 332 is operatively connected at 336 to the lock 322. to control the lock.

The control unit 328 is part of a vehicle-based transponder structure, 342, which can communicate with a portable ID 344 transponder. The presence of the ID 344 transponder in a certain region of the vehicle (e.g., an area adjacent to the vehicle) and the provision of a proper identity to the vehicle based transponder structure indicate that the authorized person is present.

Turning to the vehicle-based transponder structure 342, it is noted that the structure comprises a multiplicity of magnetic antennas 348A and 348B. Each magnetic antenna (e.g. 348A) is placed at a predefined location of the vehicle and transmits magnetic signals (e.g., 350A) that propagate in a certain associated region of the vehicle. Each magnetic antenna 348A and 348B is preferably a short cylindrical coil that can be electrically energized by the control unit 328 to produce a field pattern. In one example, the field configuration is a toroidal field configuration.

In the example shown in FIG. 7, two magnetic antennas 348A and 348B are installed in the vehicle 312. A first magnetic antenna 348A is placed inside an outside rearview mirror 352 and produces magnetic signals (BF) 350A which propagate in a region of the vehicle that is adjacent to the mirror. A second magnetic antenna 348B is placed inside the door 318 near the door handle 320 and produces magnetic signals (BF) 350B which propagate in a region of the vehicle which is close to the door handle. The first and second magnetic antennas 348A and 348B are operatively connected at 354A and 354B to the control unit 328. The magnetic antennas 348A and 348B are thereby energized to transmit their respective RF signals 350A and 350B in response to electrical excitation signals. which are produced by the control unit 328.

The BF signals 350A and 350B emitted by the magnetic antennas 348A and 348B are intended to be received by the ID 344 transponder. In response to the BF signals 350A and 350B, the ID 344 transponder transmits signals which are received by an antenna. 356 of the vehicle-based transponder structure, 342. The antenna 356 is operatively connected at 360 to the controller 328. In the preferred embodiment, the signals from the ID 344 transponder are directed to Vehicle-based transponder structure, 342, are RF signals and antenna 356 is an RF antenna.

Each magnetic antenna 348A and 348B is capable of transmitting an interrogation signal BF. In response to receiving an interrogation signal BF, the transponder of ID 344 transmits an RF access request signal, as a request to unlock the door 318. The access request signal transmits a code An appropriate security system identifies the ID 344 transponder and therefore identifies the ID transponder carrier as a person who is authorized to enter the vehicle 312.

In response to receiving the RF access request signal, the control unit 328 of the vehicle based transponder structure, 342, verifies the security code identification that is provided. If the verification of the identification is positive, the control unit 328 actuates the lock to pass it into the unlocked condition. In general terms, the vehicle based transponder structure, 342, and the ID 344 transponder are a communication structure for performing the automatic polling and unlocking sequence for the authorized person. In accordance with the present invention, the vehicle-based transponder structure 342 causes magnetic antennas 348A and 348B to transmit RF request signals in response to which the ID 344 transponder provides a request response indicating simply the presence of the ID transponder within the associated region of the vehicle. For example, the request signal is a short duration pulse consisting of a CW, and the request response signal from the ID 344 transponder is a short duration RF pulse. As an alternative to a CW pulse, each request signal transmits data.

In one embodiment, the magnetic antennas 348A and 348B are alternately energized by the control unit 328 to alternately produce the request signals. As shown in the example of the figure, only the request signal produced by the second magnetic antenna 348B is transmitted at the present time, and the other request signal (which is drawn in dotted lines) is transmitted at a different time. When the ID 344 transponder responds to a request signal, the control unit 328 identifies the magnetic antenna (eg, 348B) that has transmitted the request signal having caused the request response.

The identified magnetic antenna (e.g., 348B) is read to issue a complete interrogation signal. Since the response to the request signal indicates that the ID transponder 344 will receive signals from the identified magnetic antenna, the interrogation signal is received by the ID transponder. In turn, the ID 344 transponder provides the security code identification by means of the access request signal. After verification of the identification transmitted by means of the access request signal, the control unit 328 controls the unlocking of the door 318, as envisaged above. Figure 8 illustrates that it is possible for two identification transponders (IDs) 444 and 444 'to be in a region of the vehicle associated with one of a multiplicity of magnetic antennas (eg 448A). Such occurrence is possible when two authorized persons place their ID 444 and 444 transponders within the region. It is envisaged that the system 410 will not be prevented from determining the presence of an ID transponder. An example of a solution consists in causing the multiple transponders of ID 444 and 444 'to simultaneously respond to a request signal BF, and then to produce an interrogation signal BF which is addressed to only one of the transponders. ID (for example 444). Other known techniques can be used to avoid signal collisions.

According to the description of the invention made above, those skilled in the art will perceive improvements, changes and modifications. For example, the magnetic antennas can be at any location and can be in any number. In addition, the invention can be applied to vehicle functions other than those described herein. It is to be understood that the appended claims cover such improvements, changes and modifications within the scope of those skilled in the art.

Claims (34)

<B> <U> CLAIMS </ U> </ B> System (10, 310) for remote control of a function of a vehicle (12, 312), characterized in that it comprises. a plurality of interrogation means (48A-48F; 348A, 348B) each operable to transmit an interrogation signal (50A-50F; 350A, 350B) through a region (18, 24) of the vehicle associated with one respective interrogation means (48A-48F; 348A, 348B); portable identification means (44, 344) for receiving the interrogation signals (50A - 50F; 350A, 350B) and for transmitting a response signal (68, 358) transmitting an identification, in response to the reception of the one of the interrogation signals (50A-50F; 350A, 350B); means (34, 328) for receiving the response signal (68, 358) and performing the function of the vehicle (12, 312) in response to receiving the response signal (68, 358); and means (34, 328) for determining which region (18, 24) of the vehicle is the portable identification means (44, 344) and for operating the interrogating means (48A-48F; 348A, 348B) associated to transmit said interrogation signal (50A - 50F; 350A, 350B). 2. System according to claim 1, characterized in that the function of the vehicle (12) is the actuation of a component (28) of ignition authorization of the engine (14) of the vehicle, and the means (34) for receiving the response signal (68) and for performing the function of the vehicle comprises means for actuating the ignition enable component (28) of the engine (14) to enable ignition of the engine. 3. System according to claim 1, characterized in that the function of the vehicle (312) is the actuation of an access control component (322) of an input (318) of the vehicle (312), and the means (328) for receiving the response signal and accomplishing the function of the vehicle includes means for actuating the access control component (322) to allow access to the interior of the vehicle (312). 4. System according to claim 1, characterized in that the vehicle regions comprise a region (18, 24) extending into an interior (16) of the vehicle (12), and one of the interrogation means (48A - 48F) comprises means for transmitting the associated interrogation signal (50A, 50F) through the region extending into the interior (16) of the vehicle (12). The system of claim 1, characterized in that the vehicle regions comprise a region extending outside the vehicle (312), and one of the interrogation means comprises means (348A, 348B) for transmitting the associated interrogation signal (350A, 350B) through the region extending outside the vehicle (312). System according to claim 1, characterized in that the determining means comprises a multiplicity of request means (48A-48F; 348A, 348B), each of which can be actuated to transmit a request signal (50A - 50F). 350A, OB) through the vehicle region (12, 312) associated with a respective one of the interrogation means (48A-48F; 348A, 348E) and a respective one of the requesting means (48A - 48F). 348A, 348B), the portable identification means (44, 344) comprising means (132) for receiving the request signals (50A - 50F; 350A, 350B) and for transmitting a request response signal in response to receiving a request signal, the determining means (34, 328) further comprising means for determining which request means (48A-48F; 348A, 348B) has caused the request response signal to be transmitted by the means (132) for transmitting a request response signal. The system of claim 6, characterized by comprising means (76) for controlling the multiplicity of request means (48A-48F; 348A, 348B) for sequentially transmitting request signals (50A-50F; 350A, 350B). 8. System according to claim 6, characterized in that it comprises means (234) for controlling the multiplicity of request means (48A-48F) for simultaneously transmitting request signal groups (50A, 50D, 50B, 50E). ). 9. System according to claim 6, characterized in that the plurality of request means (48A-48F; 348A, 348B) comprises means for transmitting the request signals (50A - 50F; 350A, <B> 350E) </ B> in the form of CW signals. The system of claim 6, characterized in that the plurality of requesting means (48A-48F; 348A, 348B) comprises means for transmitting the request signals (50A-50F; 350A, 350B) to include data. 11. System according to claim 1, characterized in that the multiplicity of interrogation means (48A 48F; 348A, 348B) comprises means for transmitting the interrogation signals (50A - 50F; 350A, 350B) in the form of low frequency magnetic signals. System according to Claim 1, characterized in that the portable identification means (44, 344) comprises means (140, 144) for transmitting the response signal (68, 358) in the form of a radiofrequency signal. . 13. System (10, 310) for remote control function of a vehicle (12, 312), this system being characterized what it comprises. a plurality of interrogation means (48A-48F; 348A, 348B) each operable to transmit an interrogation signal (50A-50F; 350A, 350B) through a region (18, 24) of the vehicle associated with one respective interrogation means (48A-48F; 348A, 348B); portable identification means (44, 344) for receiving one of the interrogation signals (50A - 50F; 350A, 350B) and for transmitting a response signal (68, 358) transmitting an identifier in response to the reception said interrogation signal; means (34, 328) for receiving the response signal (68, 358) and performing the function of the vehicle in response to receiving the response signal (68, 358); and means (34, 328) for determining, prior to transmission of any of the interrogation signals (50A-50F; 350A, 350B), which interrogating means (48A-48F; 348A, 348B); must be actuated to transmit its interrogation signal (50A-50F; 350A, 350B) so that the transmitted interrogation signal is received by portable identification means (44, 344). 14. System according to claim 13, characterized in that the function of the vehicle (12) is the actuation of a component (28) of ignition authorization of the engine (14) of the vehicle, and the means (34) for receiving the response signal (68) and for performing the function of the vehicle comprises means for actuating the ignition enable component (28) of the engine (14) to enable ignition of the engine. System according to claim 13, characterized in that the function of the vehicle is the actuation of an access control component (322) of an input (318) of the vehicle (312), and the means (328) ) to receive the response signal (358) and to perform the function of the vehicle comprises means (332) for operating the access control component (322) to allow access to the interior of the vehicle (312). System according to claim 13, characterized in that the vehicle regions comprise a region (18, 24) extending into an interior (16) of the vehicle (12), and one of the interrogation means (48A). - 48F) comprises means for transmitting the associated interrogation signal (50A-50F) through the region extending into the interior (16) of the vehicle (12). The system of claim 13, characterized in that the vehicle regions comprise a region extending outside the vehicle (312), and one of the interrogation means comprises means (348A, 348B) for transmitting the associated interrogation signal (350A, 350B) through the region extending outside the vehicle (312). 18. System according to claim 13, characterized in that the determining means comprises a plurality of request means (48A-48F; 348A, 348B), each of which can be actuated to transmit a request signal (50A - 50F). 350A, 350B) through the vehicle region (12, 312) associated with respective one of the interrogating means (48A-48F; 348A, 348B) and respective one of the requesting means (48A-48F). 348A, 348B), the portable identification means (44, 344) including means (132) for receiving the request signals (50A 50F; 350A, 350B) and for transmitting a request response signal in response to the receiving a request signal, the determining means (34, 328) further comprising means for determining which request means (48A-48F; 348A, 348B) has caused the request response signal to be transmitted by the means (132) for transmitting a request response signal. 19. System according to claim 18, characterized in that it comprises means (76) for controlling the multiplicity of request means (48A-48F; 348A, 348B) for sequentially transmitting request signals (50A 50F; 350A, 350B). 20. System according to claim 18, characterized in that it comprises means (234) for controlling the multiplicity of demand means (48A-48F) for simultaneously transmitting request signal groups (50A, 50D, 50B, 50E ). 21. System according to claim 13, characterized in that the multiplicity of interrogation means (48A 48F; 348A, 348B) comprises means for transmitting the interrogation signals (50A-50F; 350A, 350B) in the form of low frequency magnetic signals. 22. System according to claim 13, characterized in that the portable identification means (44, 344) comprises means (140, 144) for transmitting the response signal (68, 358) in the form of a radiofrequency signal. . 23. System (10, 310) for remote control of a function of a vehicle (12, 312), characterized in that it comprises. a plurality of interrogation means (48A-48F; 348A, 348B), each of which can be actuated to transmit an interrogation signal (50A-50F; 350A, 350B), each interrogation signal being receivable to within a region (18, 24) of the respective associated vehicle of the interrogating means (48A-48F; 348A, 348B); portable identification means (44, 344) for receiving one of the interrogation signals (50A-50F; 350A, 350B) when said identifying means (44, 344) is located within the region respective partner (18, 24) and the respective interrogating means (48A-48F; 348A, 348B) outputs said interrogation signal, and for transmitting a response signal (68, 358) transmitting an identification, in response to the receiving said interrogation signal (50A 50F; 350A, 350B); means (34, 328) for receiving the response signal (68, 358) and performing the function of the vehicle (12, 312) in response to receiving the response signal (68, 358); and means (34, 328) for determining which of the plurality of interrogating means (48A 48F; 348A, 348B) is actuated to produce said interrogation signal (50A-50F; 350A, 350B) for reception by the identification means (44, 344), and for operating said interrogation means (48A-48F; 348A, 348B) to transmit said interrogation signal (50A 50F; 350A, 350B). 24. System according to claim 23, characterized in that the function of the vehicle (12) is the actuation of a component (28) for authorizing ignition of the engine (14) of the vehicle, and the means (34) for receiving the response signal (68) and performing the function of the vehicle comprises means for actuating the ignition enable component (28) of the engine (14) to enable ignition of the engine. 25. System according to claim 23, characterized in that the function of the vehicle is the actuation of an access control component (322) of an input (318) of the vehicle (312), and the means (328) ) to receive the response signal and to perform the function of the vehicle comprises means (332) for actuating the access control component (322) to allow access to the vehicle interior (312). 26. System according to claim 23, characterized in that the vehicle regions comprise a region (18, 24) extending into an interior () of the vehicle (12), and one of the interrogation means (48A- 48F) comprises means for transmitting the associated interrogation signal (50A, 50F) through the region extending into the interior (16) of the vehicle (12). The system of claim 23, characterized in that the vehicle regions comprise a region extending outside the vehicle (312), and one of the interrogation means comprises means (348A, 348B) for transmitting the associated interrogation signal (350A, 350B) through the region extending outside the vehicle (312). 28. System according to claim 23, characterized in that the determining means comprises a plurality of request means (48A-48F; 348A, 348B), each of which can be actuated to transmit a request signal (50A - 50F). 350A, 350B) through the vehicle region (12, 312) associated with respective one of the interrogating means (48A-48F; 348A, 348B) and respective one of the requesting means (48A-48F). 348A, 348B), the portable identification means (44, 344) including means (132) for receiving the request signals (50A - 50F; 350A, 350B) and for transmitting a request response signal in response thereto. receiving a request signal, the determining means (34, 328) further comprising means for determining which request means (48A-48F; 348A, 348B) has caused the request response signal to be transmitted by the means (132) for transmitting a request response signal. 29. System (10,310) for remote control of a function of a vehicle (12,312), which system is characterized by comprising. a plurality of antennas (48A-48F; 348A, 348B) each operable to output a request signal (50A-50F; 350A, 350B) and an interrogation signal (50A-50F; 350A; <B> 350E) </ B> through an associated region (18, 24) of the vehicle; a transponder (44, 344) for receiving the request signals (50A-50F; 350A, 350B) and for transmitting a first response signal (68, 358) transmitting an indication of presence in response to the reception of one of the request signals (50A - 50F; 350A, 350B), and for receiving the interrogation signals (50A - 50F; 350A, 350B) and for transmitting a second response signal (68, 358) transmitting an identification in response to the receiving one of the interrogation signals (50A - 50F; 350A, 350B); and a control unit (34, 328) for controlling the sequential transmission of the request signals (50A-50F; 350A, 350B) to determine which antenna (48A-48F; 348A, 348B) is associated with an occurrence of the transponder transmitting the first response signal (68, 358) to cause the determined antenna to transmit its interrogation signal (50A-50F; 3OA, 350B), and to perform the function of the vehicle ( 12, 312) in response to transmission by the transponder (44, 344) of the second response signal (68, 358) due to the reception of the transmitted interrogation signal. 30. System according to claim 29, characterized in that the function of the vehicle (12) is the actuation of an ignition authorization component (28) of the engine (14) of the vehicle. 31. System according to claim 29, characterized in that the function of the vehicle (312) is the actuation of an access control component (322) of an inlet passage (318) of the vehicle. A transponder for a system which remote-controls a function of a vehicle (12), said transponder (44) being characterized in that it comprises: means (124, 128) for receiving any of a plurality of request signals ( 50A - 50F) which can be transmitted through respective regions (18, 24) of the vehicle; means (132, 140, 144) for transmitting a first response signal (68) transmitting a presence indication for a respective region in response to receiving one of the request signals (50A-50F); means (124, 128) for receiving any one of a plurality of interrogation signals (50A - 50F) which can be transmitted through respective regions (18, 24) of the vehicle interior (16); and means (136,140,144) for transmitting a second answer signal (68,358) transmitting an identification in response to receiving the interrogation signal associated with the respective region (18,24). 33. A method for remotely controlling a function of a vehicle (12, 312), characterized in that it comprises establishing a plurality of interrogation means (48A-48F; 348A, 348B), each thereof being operable to transmit a signal (50A-50F; 350A, 350B) through a region (18, 24) of the vehicle associated with a respective one of the interrogating means (48A-48F; 348A, 348B) ; determining the region of the vehicle in which a portable identification means is located (44, 344); actuating the associated interrogation means (48A-48F; 348A, 348B) to transmit an interrogation signal (50A - 50F; 350A, 350B); receiving the interrogation signal by means of portable identification (44, 344); transmitting, by the portable identification means (44, 344), a response signal (68, 358) which transmits an identification, in response to the reception of the interrogation signal (50 - 50F; OA, 350B) ; means (34, 328) for receiving the response signal (68, 358); and accomplishing the function of the vehicle in response to receiving the response signal 358). 34. A method of remote controlling a vehicle function, said method being characterized by comprising transmitting a plurality of request signals 50A-50F; 350A, 350B), in one sequence, through associated regions (18, 24) of the vehicle (12, 312); receiving a request signal (50A-50F; 350A, 350B) in a transponder (44, 344) located within an associated region (18, 24); transmitting by the transponder (44, 344) a first response signal, which transmits a presence indication in response to receiving said request signal (50A-50F; 3, 350B); determining the region (18, 24) in which the transponder (44, 344) is located, using first response signal (68, 358); transmitting an interrogation signal (50A-50F; 350A, 350B) which is associated with the region (18, 24) in which the transponder (44, 344) is located; receiving the interrogation signal (50A - 50F; 350A, 350B) to the transponder (44, 344); transmitting by the transponder (44, 344) a second response signal (68, 358) that transmits an identification in response to receiving said interrogation signal (50A 50F; 350A, 350B); and accomplishing the function of the vehicle in response to the transmission of the second response signal (68, 358) by the transponder (44, 344).