Access arrangement for a vehicle

Abstract

Access order (ZA) for a vehicle (FZ), with the following features: a vehicle-side transmitting / receiving device (SEF) for the sequential transmission of query signals (AFX) in first predetermined time intervals (TI1); at least one mobile identification transmitter (IDT) with adjustable receive sensitivity (E), configured to perform automatic dynamic adjustment of the receive sensitivity (E) by continuously reducing or increasing the receive sensitivity (E) in order to obtain a receive sensitivity (E) value that approximately represents the distance of the mobile identification transmitter to the vehicle, comprising the following components: an identifier-side transmit / receive device (SEI) with adjustable receive sensitivity (E): for receiving the query signals (AFX) from the vehicle's transmit / receive device, a verification device (UEI, UEF) to issue a control command (STB1) to reduce the sensitivity (E) of the identifier-side transmitter / receiver (SEI) by a first predetermined amount (B1) when the identifier-side transmitter / receiver (SEI) has received a predetermined number of query signals (AFX) transmitted by the vehicle-side transmitter / receiver (SEF), and a timing device (TDM) for measuring predetermined time intervals, which, after the expiry of a second predetermined time interval (TI2), causes the verification device (UEI) to issue a third control command (STB3) to increase the receive sensitivity of the identifier-side transmit / receive device (SEI) by a third predetermined amount (B3) if the identifier-side transmit / receive device (SEI) has not received an interrogation signal (AFX) after the expiry of the second predetermined time interval (TI2), where the magnitude of a second predetermined time interval (TI2) is greater than the magnitude of a first predetermined time interval (TI1).

Description

[0001] The present invention relates to an access arrangement for a vehicle, in particular a motor vehicle, and to a method for operating such an access arrangement for a vehicle. The invention further comprises a vehicle with the aforementioned access arrangement.

[0002] To prevent unauthorized access to a vehicle, especially a motor vehicle, modern access control systems or access arrangements in vehicles use electronic security systems. These systems authenticate a user through data communication between a first communication device in the vehicle and a second communication device in a user's mobile identification device, such as a key or key fob. With an active access arrangement, the mobile identification device sends control signals and an identification code to the vehicle, for example, when the user presses a specific button. If the identification code is correct, the vehicle is then unlocked or locked.

[0003] In a so-called passive access arrangement, a primary communication device in the vehicle initially transmits request signals of a specific field strength at regular intervals to check whether a mobile identification device is within a proximity or detection range around the vehicle. If a mobile identification device approaches the vehicle and is able to receive its request signals, it will respond with a corresponding reply signal to initiate an authentication or pre-authentication process. During this process, data is exchanged in which the mobile identification device ultimately transmits its authentication code to the vehicle.Upon successful verification of the authentication code, a user located directly at the vehicle can then unlock the corresponding vehicle door or all vehicle doors by operating a door handle. Since no active operation of a mechanical or electrical identification device or key is required by the user, this type of access authorization is also referred to as passive access authorization verification, and the corresponding access authorization systems as passive electronic access authorization systems.

[0004] With such a passive access arrangement as just described, the following problematic situation can arise. A user or driver parks their vehicle in the garage and leaves it. They then hang their jacket, in which they have inadvertently left their key, on a hook near the vehicle and leave the garage. As mentioned above, the vehicle continues to send out request signals at regular intervals, which are received by the key in the jacket because it is within the vehicle's detection range. In other words, the key is activated by each request signal from the vehicle, generates a response signal, and sends it back to the vehicle.Although this does not imply any desire on the part of the driver to perform authentication in order to enter the vehicle, the key is unnecessarily consumed by the regular waking by a request signal and the transmission of a corresponding response signal, thus reducing the operating time of the key / identification transmitter. Furthermore, the vehicle itself also consumes unnecessary power by receiving and processing the corresponding response signals.

[0005] The publication DE 10 2006 053 615 B4 discloses an access arrangement for a vehicle in which, after receiving a specific query signal, the reception sensitivity of the identification transmitter / receiver is reduced.

[0006] The publication DE 10 2006 035 651 B4 discloses an access arrangement for a vehicle in which a power level of a demand signal power of a transmitter is variably adjustable.

[0007] Document DE 103 346 25 A1 discloses an access arrangement for a vehicle in which the vehicle sends query signals to an identification transmitter at predetermined time intervals.

[0008] The publication EP 1 638 063 A2 discloses a portable device with a receiver for receiving a request signal from a vehicle-internal device and a control unit for lowering or raising the signal reception sensitivity of the receiver by predetermined levels in order to adjust the signal reception sensitivity.

[0009] Therefore, the object of the present invention is to provide a means by which safe operation of an access arrangement can be ensured with minimized power consumption.

[0010] This task is solved by the subject matter of the independent claims. Advantageous embodiments are the subject matter of the dependent claims.

[0011] An access control or identification system for a vehicle, which in particular controls access to the vehicle, comprises the following features. It has a vehicle-side transmitter / receiver for sequentially transmitting query signals at predetermined time intervals. Furthermore, the access control system has at least one mobile identification transmitter (or a portable user identification device) with adjustable receiver sensitivity, configured to automatically and dynamically adjust the receiver sensitivity by continuously reducing or increasing it to achieve a sensitivity value that approximately represents the distance between the mobile identification transmitter and the vehicle, with the following components.The mobile identification transmitter (or at least one mobile identification device) has a transmitter / receiver unit with adjustable receiver sensitivity for receiving query signals from the vehicle-side transmitter / receiver unit, as well as a verification unit for issuing a control command to reduce the sensitivity of the transmitter / receiver unit by a predetermined amount after it has received a predetermined number of query signals transmitted by the vehicle-side transmitter / receiver unit. Reducing the sensitivity of the transmitter / receiver unit prevents it from responding to query signals from the vehicle-side transmitter / receiver unit; that is, it no longer processes query signals or transmits a corresponding response signal.In this way, electricity can be saved in the mobile identification device as well as in the vehicle if the mobile identification device is in a detection range of the vehicle or the vehicle's transmitter / receiver, but is in a static state, i.e., does not move relative to the vehicle.

[0012] According to one embodiment of the access control system, the verification device is configured to issue a second control command upon (proper) reception of another query signal by the identifier's transmitter / receiver unit, which now has reduced reception sensitivity. This second command further reduces the transmitter / receiver unit's reception sensitivity by a second predetermined amount. This means that if the mobile identifier is already reducing its reception sensitivity, this embodiment allows the transmitter / receiver unit's reception sensitivity to be rapidly reduced further based on just a single (additional) query signal. In this way, the reception sensitivity is quickly lowered, enabling the device to enter a power-saving mode.To achieve a rapid initial reduction in receive sensitivity and thus quickly enter a "power-saving mode," it is conceivable to set the first predetermined amount for reducing receive sensitivity higher than the second predetermined amount. However, it is also possible to set both amounts for reducing receive sensitivity to the same value, or to set the second predetermined amount higher than the first.

[0013] To determine whether reception is successful, a pattern can be transmitted along with the vehicle's interrogation signal. The mobile identification device can recognize this pattern if the field strength of the interrogation signal at the mobile identification device's location exceeds a predetermined detection threshold. In other words, if the mobile identification device is within the vehicle's proximity or detection range, the interrogation signal from the vehicle's transceiver, including the transmitted pattern, can be detected by the mobile identification device.

[0014] According to the invention, the access arrangement includes a timing device (“timer”) configured to measure predetermined time intervals. In particular, the timing device is configured to measure a second predetermined time interval, as described below. The advantage of using such a timing device is that, after the identification transmitter / receiver has reduced its receiver sensitivity at a certain point in time, as described above, it can no longer receive a query signal from the vehicle. In other words, by reducing the receiver sensitivity to a predetermined low level, a mobile identification transmitter is no longer able to determine whether it is still in the same position or whether, for example, it has moved further away from the vehicle.The mobile identification transmitter can only determine that it is moving towards the vehicle if it suddenly receives vehicle-side query signals again, as these signals will then have a greater field strength at the location of the mobile identification transmitter due to the increased proximity to the vehicle. However, to enable the mobile identification transmitter to determine its location and whether it is still in a static state, a timing device is provided according to this design. In particular, the timing device can be integrated into the mobile identification transmitter.

[0015] The measurement of a second time interval can begin either after the (proper) reception of a query signal or after the expiration of a (previous) second time interval. If a query signal is received by the identifier's transmitter / receiver before the expiration of a second time interval, the timing device advantageously restarts the measurement. In other words, the mobile identifier, or its transmitter / receiver, is triggered to wake up or execute a predetermined command either by receiving a query signal from the vehicle or by a (time) signal from the timing device.

[0016] According to the invention, it is provided that, after the second predetermined time interval has elapsed, the timing device causes the verification device to issue a third control command in order to increase the reception sensitivity of the identifier-side transmitter / receiver device by a third amount if the identifier-side transmitter / receiver device has not received a query signal after the second predetermined time interval has elapsed, wherein the amount of a second predetermined time interval is greater than the amount of a first predetermined time interval.This means that if, in the preceding process, the receiver sensitivity of the identification transmitter's transceiver was reduced to such an extent that it could no longer receive vehicle-side query signals, the timing device will cause the verification device to increase the receiver sensitivity of the identification transmitter's transceiver by at least a third predetermined amount. This third predetermined amount can be equal to the first or second predetermined amount (when the receiver sensitivity was reduced), or it can be greater than the first or second predetermined amount, so that a higher receiver sensitivity is quickly restored, thereby also enabling faster detection of the mobile identification transmitter moving away from the vehicle.If the identification transmitter / receiver is again able to receive a query signal from the vehicle, it can conclude that it is still near the vehicle and, in particular, in a static state (at the same location as when it last received a query signal from the vehicle). As mentioned above, it can then reduce its reception sensitivity. By automatically and dynamically adjusting the reception sensitivity (by continuously reducing or increasing it), a sensitivity value can ultimately be achieved that roughly represents the distance between the mobile identification transmitter and the vehicle. This automatic adjustment of the reception sensitivity reduces power consumption in the mobile identification transmitter (and ultimately in the vehicle as well).

[0017] In particular, if the value of a second time interval is chosen to be larger or many times larger than the value of a first time interval, it is possible for the mobile identification device to avoid receiving, processing, or responding to a large number of vehicle-side query signals in a static state (due to the insensitivity of the identification device's transmitter / receiver). This allows for energy savings on both the mobile identification device and the vehicle side. However, it should be noted that a mobile identification device remains fully functional despite the reduced receiver sensitivity, as it can still receive and respond to vehicle-side query signals with higher or increased field strength, such as those that occur when approaching the vehicle's transmitter / receiver. Only at a specific location within the detection range...When approaching the vehicle where it is resting (because it was forgotten, for example), it is put into a power-saving mode as explained above.

[0018] While, according to the above configuration, the verification device generally issues the second control command upon receipt of a further query signal by the identifier-side transmitting / receiving device, the verification device can also be connected to the timing device in such a way that it issues the second control command before the expiry of a second predetermined time interval upon receipt of a further query signal.

[0019] According to a further embodiment of the access arrangement, the transmitter / receiver on the identification device side is configured to send a response signal in response to one or more query signals. This response signal can transmit various pieces of information back to the vehicle. For example, field strength values ​​measured at the location of the mobile identification device from corresponding query signals, the currently set receive sensitivity of the transmitter / receiver on the identification device side, and / or an authentication code of the mobile identification device can be transmitted to the vehicle. Based on this information, a vehicle control unit can then decide whether to issue a specific control command.For example, when an authorized mobile identifier (which has transmitted a valid authentication code) is within a certain distance of the vehicle, the vehicle's control unit can send a signal to a light source, such as a turn signal, to provide a welcome signal to the driver carrying the mobile identifier. The distance of the mobile identifier from the vehicle can be determined either by measuring and transmitting the field strength values ​​of query signals at the location of the mobile identifier, or by adjusting the receiver sensitivity of the identifier's transmitter / receiver when receiving the query signals.

[0020] For example, assuming a mobile identification device approaches an assigned vehicle from a greater distance, the device will enter the vehicle's reception range at a certain distance, where it can receive interrogation signals from the vehicle. Assuming such a reception range has a radius of approximately 5 to 10 meters around the vehicle, approaching the vehicle will typically take several seconds.To further conserve power during such an approach on the part of the mobile identification device, according to one embodiment of the access arrangement, the timing device is designed to measure a third predetermined time interval after receiving a predetermined number of query signals (for example, upon entering the detection area). The transmitter / receiver on the identification device is designed to send a response signal upon receiving the last of the predetermined number of query signals and then not send any further response signals until the end of the third predetermined time interval. In particular, if a third predetermined time interval is chosen to be much larger than a first predetermined time interval, the transmitter / receiver on the identification device will not send a response signal for a relatively long time and thus conserve power.

[0021] According to a further embodiment of the access arrangement, after the receiver sensitivity of the identifier's transmitter / receiver has been set to a predetermined value, the verification device does not change the receiver sensitivity further until the identifier's transmitter / receiver has received a predetermined number of query signals and responded accordingly. Such an embodiment of the access arrangement is particularly helpful when specific zones within the detection range need to be defined. For example, a zone further away from the vehicle and a zone closer to the vehicle can be defined within the detection range by the mobile identifier analyzing the receiver sensitivity of the identifier's transmitter / receiver accordingly.Since, after appropriate (repeated) adjustment by the verification device, this corresponds approximately to the distance between the mobile identification transmitter and the vehicle, the transition to a different zone can be detected by adjusting the receiver sensitivity. It must then be ensured that a predetermined number of query signals are received and a corresponding response signal is sent back to the vehicle so that it, or rather its control unit, can execute an appropriate control command. For example, after the sensitivity of the transmitter's transceiver has been set to or below a predetermined value, the verification device can be configured so that it does not reduce the sensitivity further until the transmitter's transceiver has received a predetermined number of query signals and responded accordingly.This can happen if the mobile identification transmitter moves from a zone further away from the vehicle to a zone closer to the vehicle, where the predetermined sensitivity value essentially represents the zone boundary.

[0022] According to a further embodiment, the receiver sensitivity of the identification device's transmitter / receiver unit should only be adjustable down to a minimum value. This minimum value corresponds to a receiver sensitivity necessary to enable the device to receive the vehicle's query signal at a location directly adjacent to the vehicle, e.g., up to 0.5 m away. This is intended to ensure that an authorization process for the mobile identification device vis-à-vis the vehicle is possible in every case, and that a successful outcome of this process, for example, unlocks or opens a vehicle door.

[0023] According to a further embodiment of the access control arrangement, the intelligence for evaluation and control is provided for in the mobile identification device. In this regard, the mobile identification device can have a control unit on the device side for controlling the transmitter / receiver unit on the device side, in which the verification device is integrated. Furthermore, the mobile identification device can have a storage unit on the device side for storing any evaluated field strength values ​​of received query signals and / or the reception sensitivities set for each query signal received. In this way, it is possible to compare the field strengths of two query signals (possibly corrected for the respective reception sensitivity) that were received by the mobile identification device at different times.

[0024] In order to make a simple comparison regarding the field strength of two query signals, the vehicle-side transmitting / receiving device is advantageously set up to transmit query signals with the same and / or constant transmitting field strength values.

[0025] According to another aspect of the invention, a vehicle is created with an access arrangement as shown above or as an embodiment thereof.

[0026] According to a further aspect of the invention, a method for operating an access device for a vehicle, in particular according to the above description or an embodiment thereof, is provided. The method comprises the following steps: Several query signals are transmitted by the vehicle at (regular) predetermined time intervals. These query signals are received by at least one mobile identification transmitter with adjustable reception sensitivity. Optionally, a corresponding response signal can be transmitted in reaction to the reception of one or more query signals. The reception sensitivity of the mobile identification transmitter is automatically and dynamically adjusted by continuously reducing or increasing it.Increasing the receive sensitivity to obtain a receive sensitivity value that approximately represents the distance of the mobile identifier to the vehicle, as follows: A control command is issued to reduce the receive sensitivity of the mobile identifier by a predetermined amount when the identifier-side transceiver has received a predetermined number of query signals transmitted by the vehicle-side transceiver.Furthermore, a third control command is issued after a second predetermined time interval to increase the receiving sensitivity of the identifier-side transmitting / receiving device by a third predetermined amount if the identifier-side transmitting / receiving device has not received an interrogation signal after the second predetermined time interval, wherein the amount of a second predetermined time interval is greater than the amount of a first predetermined time interval.

[0027] In this way, the method allows a mobile identification transmitter that is in a static state, for example because it was left at a specific location near the vehicle, to reduce its reception sensitivity and thus no longer have to receive, evaluate, or respond to query signals, at least for a certain period of time. This saves power, particularly for the mobile identification transmitter, but also for the vehicle.

[0028] Advantageous configurations of the access arrangement are, insofar as they are transferable to the vehicle or the procedure, also applicable as advantageous configurations of the vehicle or the procedure, and vice versa.

[0029] Exemplary embodiments of the present invention will now be explained in more detail with reference to the accompanying drawings. These show: Fig. 1 a schematic representation of a passive electronic access authorization system or an access arrangement according to an embodiment of the invention; Fig. 2 a flowchart for adjusting the receiving sensitivity of a mobile identification transmitter that enters and moves out of a detection range of the vehicle.

[0030] It should first be on Fig. Reference is made to Figure 1, which shows a passive access arrangement ZA for a vehicle FZ, which is specifically designed as a motor vehicle. A vehicle-side transmitter / receiver SEF is provided as a central component of the vehicle-side part of the access arrangement. This transmitter / receiver is designed to transmit query signals AFX regularly at predetermined time intervals TI1 (see Figure 1). Fig. 2) to transmit ANF via a vehicle-mounted antenna. The query signals AFX are transmitted from the ANF antenna with the same or constant transmission field strength.

[0031] If a mobile identification device (IDD) is located within a detection range (EFB) around the vehicle (FZ), it can properly receive the query signals (AFX). In particular, the query signals (AFX) can contain a code or a predetermined pattern that is recognized by an IDD within the detection range (EFB). Such a pattern is no longer recognized by an IDD at position POS3 (left in the figure), so proper reception is no longer possible at this position.

[0032] To illustrate the flowchart for setting a receiver sensitivity in a mobile IDG identification transmitter, see in Fig. Figure 1 shows the identification device IDG (as a mobile component of the access control system ZA) at three different positions: POS1, POS2 (both within the detection range EFB), and POS3. The identification device IDG comprises an identification device-side transmitter / receiver unit SEI, which receives vehicle-side query signals AFX via an identification device-side antenna ANI and, in turn, transmits corresponding response signals AWX via the same antenna. Furthermore, the identification device-side transmitter / receiver unit SEI can be configured to evaluate the field strength FSX of a received vehicle-side query signal AWX at the location of the mobile identification device IDG, for example, as part of an RSSI (Received Signal Strength Indication) measurement.Furthermore, the mobile identification device IDG has an identification-side control unit STI for controlling the identification-side transmitter / receiver unit SEI, which includes a verification unit UEI. The verification unit is configured to issue a control command to set the receive sensitivity E of the identification-side transmitter / receiver unit SEI.

[0033] As described in the following Fig. As will be explained in section 2, this setting is based on the acquisition of a specific number of interrogation signals at specific times. For the purpose of setting the receive sensitivity E, control commands STBY are transmitted from the control unit STI or the verification unit UEI to the transmitter / receiver unit SEI on the identifier side. The placeholder "Y" in the reference symbol STBY is intended to clarify that a multiple of different control commands can be sent from the control unit STI to the transmitter / receiver unit SEI to set the receive sensitivity E.

[0034] The mobile identification transmitter IDG also includes a timer ZME to measure predetermined time intervals (see also Fig. 2) to measure. Furthermore, the mobile identification transmitter IDG has an actuation element in the form of a TAI button, which can be operated by a user or driver. By pressing the TAI button, the user can manually reset the receiving sensitivity of the mobile identification transmitter IDG, for example, back to a default state (e.g., with high sensitivity).

[0035] Furthermore, the IDG mobile identification transmitter features an SPI memory unit in which the evaluated field strength of a received query signal and / or the reception sensitivity value set for receiving the query signal can be stored. By storing the evaluated field strength value of a query signal or the reception sensitivity set for receiving the query signal, a comparison can be made with the evaluated field strength of another query signal received by the transmitter's transceiver unit. This comparison allows the system to determine the direction in which a mobile identification transmitter is moving (towards or away from the vehicle). If the currently measured field strength value is higher than the stored value, it can be inferred, for example, that the mobile identification transmitter is approaching the vehicle.

[0036] After explaining the essential components of the access order ZA, the following should be noted: Fig. 2 is referenced, which shows a possible procedure for setting the receiver sensitivity E of the identifier-side transmitter / receiver unit SEI in the case that the identifier IDG moves into the vehicle in a detection area EFB, is within the detection area for a certain time, and then moves out of the detection area again.

[0037] The basis for describing the process of adjusting the receive sensitivity E is in Fig. 2 a diagram in which the time in seconds is plotted on the X-axis, while the Y-axis shows the set receive sensitivity E of the identifier-side transmitting / receiving device SEI or the distance of the mobile identifier to the vehicle.

[0038] The example of Fig. 2. It is further assumed that the vehicle FZ or the vehicle-side transmitter / receiver SEF regularly transmits the query signals AFX at predetermined time intervals TI1 of 300 milliseconds. These query signals are low-frequency signals, or LF (low frequency) signals, with the transmission field strength selected such that they have a range of 5 m in this example.

[0039] Furthermore, it is assumed that the identifier IDG is still outside the EFB detection area at time T0, for example at the location in Fig. Position POS3 is shown in section 1. According to the illustration of Fig. 2. At time T0, the identification transmitter IDG is located 6 m from the vehicle. At this time, the receive sensitivity E is set to an output level EA (at maximum sensitivity), meaning that the identification transmitter's transceiver SEI is still able to properly receive vehicle-side query signals AFX transmitted from a vehicle 5 m away. The higher the receive sensitivity E is set, the greater the range for signals that can be received by the mobile identification transmitter.

[0040] Between time T0 and time T1, query signals AWX are transmitted by the vehicle, but are not received by the mobile identification transmitter (IDG) due to the excessive distance between the mobile identification transmitter and the vehicle. Only at time T1, when the mobile identification transmitter (IDG) enters the vehicle's detection range (EFB), does the mobile identification transmitter (IDG), as shown in the diagram, become operational. Fig. For example, the mobile identification device (IDG) can be located at position POS2 and is able to receive the vehicle's query signals AFX. The IDG is designed to receive three query signals AFX starting at time T1, process them, and send a corresponding response signal AWX to the vehicle (see also the line on the X-axis, which indicates the activity of the response signal. While no response signal is sent for most of the time – the response signal line is located on the X-axis here – a response signal is sent between times T1 and T2, and again at time T19). Each response signal could contain, for example, an authentication code for the mobile identification device. However, it is also conceivable that it could contain field strengths of the query signals measured at the location of the mobile identification device in the form of field strength values ​​FSX, or possibly other values.with the currently set receive sensitivity E to be sent to the vehicle. After a predetermined number of query signals (namely the three mentioned query signals) have been received and answered with corresponding response signals upon entering the detection range EFB, the verification device UEI will issue a first control command STB1 to the identification transmitter / receiver SEI at time T2, so that it reduces its receive sensitivity E by a first predetermined amount B1. In the example of... Fig. 2. The sensitivity E is reduced in such a way that the range for query signals to be received by the vehicle is reduced from 5 to 4 meters (i.e. by one meter).

[0041] Therefore, at time T3, it is not possible for the mobile identification transmitter IDG to receive query signals from the vehicle, as its distance to the vehicle is greater than the set range or sensitivity of the transmitter's transmitting / receiving device.

[0042] At time T4, the mobile identification transmitter (IDG) approached the vehicle to within four meters, which corresponds to the sensitivity E or range of the transmitter's transceiver (SEI). Consequently, the SEI is again able to receive query signals (AWX) from the vehicle. The mobile identification transmitter (IDG) is now configured such that, after the verification unit (UEI) detects that another query signal (AFX) from the vehicle has been detected by the mobile identification transmitter at time T4, it issues a second control command (STB2) to reduce the receive sensitivity (E) by a second predetermined amount (B2). More precisely, the receive sensitivity is reduced in such a way that the range for query signals received from the vehicle is decreased by half a meter (in this example, from 4 to 3.5 meters).

[0043] As in the example of Fig. As shown in Figure 2, the mobile identification transmitter moves in a straight line towards the vehicle from time T5 to time T6, reducing the distance between the mobile identification transmitter and the vehicle to 1.5 meters in this example. As described for times T3 to T5, the receiver sensitivity is further reduced. As in the example, the first predetermined value E1 was chosen to be twice as large (one meter) as the second predetermined value (0.5 meters). This ensures that, upon entering the detection range, where the mobile identification transmitter consumes a significant amount of power for receiving, processing, and transmitting signals, the receiver sensitivity is reduced as quickly as possible, thus lowering power consumption.

[0044] At time T6, the mobile identification device (IDG) ends its approach to the vehicle and begins moving away from it again. However, at time T7, a query signal is still being received, which is why the verification device issues a second control command STB2 so that the IDG's transmitter / receiver reduces its reception sensitivity E by the second predetermined amount B2, namely to a sensitivity or range of one meter. Since the mobile identification device is, for example, approximately 3.5 meters away from the vehicle at time T8, it will not be able to receive a query signal from the vehicle at its set sensitivity or range.In order to not only automatically reduce the receiver sensitivity E, as previously explained, but also automatically increase it again, the mobile identification transmitter IDG has the timing device ZME, which is capable of measuring predetermined time intervals. In principle, upon receiving a vehicle-side query signal AFX, the timing device ZME will (re)start measuring a second predetermined time interval TI2, for example, of 1.9 seconds (s). (Since a time interval of 1.9 s is never reached between the receipt of one query signal and the receipt of the next, the timing device ZME is never able to complete the entire time interval TI2, but is always interrupted beforehand and restarts the counting / measurement.)

[0045] As mentioned above, since the receiver sensitivity was reduced to a range of 1 m at time T7, and the mobile identification transmitter has moved further away from the vehicle, the measurement of the predetermined second time interval, permitted by the timing device ZME at time T7, can now be fully carried out. The mobile identification transmitter is designed such that at time T9, after the second predetermined time interval has elapsed, the verification device is prompted to issue a third control command STB3 to increase the receiver sensitivity E of the transmitter's transceiver by a third predetermined amount B3. This third predetermined amount B3 corresponds to an increase in sensitivity of 1 m and is therefore twice as large as the second predetermined amount B2.With the increase in receiver sensitivity at time T9, the measurement of a further second time interval is simultaneously started again by the timing device ZME.

[0046] As it now in Fig. As shown in Figure 2, even after increasing the sensitivity, the receiver is still insufficient to receive a query signal from the vehicle because the mobile identification transmitter (IDG) is still too far away. Therefore, the next predetermined time interval, TI2, will also expire at time T10. Consequently, the timing device instructs the verification device (UEI) to issue a third control command to increase the receiver sensitivity E of the IDG's transmitter / receiver (SEI) by the third predetermined amount. Furthermore, the timing device (ZME) is again instructed to measure the second predetermined time interval, TI2.After the receive sensitivity E has been increased by the third predetermined amount B3 at time T11, resulting in a range of 3 m while the distance to the vehicle is slightly more than 2 m, the identification transmitter / receiver SEI receives another interrogation signal AFX from the vehicle. The verification unit UEI then issues a second control command STB2 to decrease the receive sensitivity by a second predetermined amount B2. At time T12, the identification transmitter / receiver SEI receives another interrogation signal AFX from the vehicle, so the verification unit UEI again issues a second control command STB2 to decrease the receive sensitivity E by a second predetermined amount B2.

[0047] Once the receiver sensitivity E has dropped back to a value with a range of 2 m, the mobile identification transmitter IDG can no longer receive any vehicle-side query signals. Therefore, the timing device will count a complete second time interval TI2 until time T13. Afterwards, the timing device ZME causes the verification device to issue a third control command STB3 to increase the receiver sensitivity E of the identification transmitter's transceiver by the third predetermined amount B3. Since the mobile identification transmitter IDG will be in a position to move during this period of approximately...If the mobile identification transmitter is not moving (in a static state) for 9.5 seconds to 18 seconds, the receiver sensitivity E is automatically and dynamically adjusted between times T10 and T14, remaining below the distance between the mobile identification transmitter and the vehicle for most of the time in order to avoid receiving vehicle-side query signals in this static state and thus save power.

[0048] At time T14, after the sensitivity E has been increased again by a third predetermined amount B3, the mobile identification transmitter receives a query signal from the vehicle, whereupon the verification device UEI reduces the receiving sensitivity again by a second predetermined amount B2. As the mobile identification transmitter IDG then moves further away from the vehicle, the timing device ZME increases the receiving sensitivity E by a second predetermined amount B2 after the first predetermined second time interval TI2 has elapsed at time T15, and then increases it again by a third predetermined amount B3 after the second predetermined second time interval TI2 has elapsed at time T17.

[0049] However, since the mobile identification transmitter reversed its direction of movement at time T16 and is now moving rapidly towards the vehicle, it is possible that the mobile identification transmitter can receive four consecutive query signals from the vehicle starting at time T18. The mobile identification transmitter is designed such that, after entering the "power-saving mode" at time T2 with the reduction of its reception sensitivity, it will only transmit a response signal (AWS) again if a predetermined number of query signals from the vehicle have been received—in this example, four consecutive ones. Thus, at time T19, the mobile identification transmitter, or rather its transmitter-side transceiver (SEI), transmits a response signal that can be received by the vehicle-side transceiver (SEF).The system now knows that the mobile identification transmitter (IDG) is moving rapidly towards the vehicle and can take appropriate action. For example, the vehicle's transmitter / receiver (SEF) can forward the response signal from the mobile identification transmitter to a vehicle control unit (STF), which in turn issues a light control command (LSTB) to a light source, in particular a turn signal or ambient lighting (LQ), to activate this light source for a specific period of time, for example, 10 seconds.

[0050] After the response signal is issued, the receiver sensitivity E of the identifier-side transmitter / receiver is readjusted or reduced if possible, as previously described.

[0051] According to an advantageous embodiment of the [document / section] with reference to Fig. In accordance with the described method for adjusting the receive sensitivity E, it is conceivable that the mobile identification transmitter is further designed such that, after transmitting the last response signal and before reducing the receive sensitivity E, it allows the timing device ZME to count or measure a third predetermined time interval TI3, whereby the transmitter-side transmitting / receiving device SEI must not transmit a response signal until the end of this third predetermined time interval TI3 in order to save power. This configuration is described in Fig. 2 such that at time T2 and at time T19 a corresponding third predetermined time interval begins to run, within which no response signal may be sent to the vehicle.

[0052] According to a further embodiment, it is conceivable that, as demonstrated at time T19, in the mode with reduced receive sensitivity E, a response signal is only transmitted by the identifier-side transmitter / receiver if it has previously received four vehicle-side query signals AFX (correctly). This will be the case, in particular, when a driver approaches quickly and over a longer period of time with their mobile identifier, as occurred between times T18 and T19. In contrast, the approach between times T9 and T10, while rapid, was too short a period to be recognized as such by the vehicle.

[0053] According to a further embodiment of the invention, it is also conceivable that the detection area EFB of the vehicle is divided into two or more zones, with the mobile identification transmitter, as well as the vehicle, exhibiting a corresponding reaction upon entering the respective zone. In order for the identification transmitter to indicate entry into a specific zone to the vehicle, despite its power-saving method, it is possible that the verification device UEI, after setting a specific sensitivity E corresponding to a specific range or zone within which the mobile identification transmitter must be located to receive vehicle-side query signals, does not further change the receiving sensitivity until the identification transmitter's transmit / receive device SEI has received a predetermined number of query signals and responded accordingly with a reply signal.Particularly when the mobile identification transmitter approaches the vehicle, the verification device UEI, after setting the receive sensitivity E to or below a predetermined value, can no longer reduce the sensitivity further (only increase it) until the transmitter's transceiver has received a predetermined number of query signals and responded accordingly with a reply signal. This can occur, for example, when crossing from the point in . Fig. Zones Z1 shown in Z2 of the detection area EFB are provided for.

Claims

[1] Access arrangement (ZA) for a vehicle (FZ), with the following features: a vehicle-side transmitting / receiving device (SEF) for the sequential transmission of query signals (AFX) in first predetermined time intervals (TI1); at least one mobile identification transmitter (IDT) with adjustable receive sensitivity (E), configured to perform automatic dynamic adjustment of the receive sensitivity (E) by continuously reducing or increasing the receive sensitivity (E) in order to obtain a receive sensitivity (E) value that approximately represents the distance of the mobile identification transmitter to the vehicle, comprising the following components: an identifier-side transmit / receive device (SEI) with adjustable receive sensitivity (E): for receiving the query signals (AFX) from the vehicle's transmit / receive device, a verification device (UEI, UEF) to issue a control command (STB1) to reduce the sensitivity (E) of the identifier-side transmitter / receiver (SEI) by a first predetermined amount (B1) when the identifier-side transmitter / receiver (SEI) has received a predetermined number of query signals (AFX) transmitted by the vehicle-side transmitter / receiver (SEF), and a timing device (TDM) for measuring predetermined time intervals, which, after the expiry of a second predetermined time interval (TI2), causes the verification device (UEI) to issue a third control command (STB3) to increase the receive sensitivity of the identifier-side transmit / receive device (SEI) by a third predetermined amount (B3) if the identifier-side transmit / receive device (SEI) has not received an interrogation signal (AFX) after the expiry of the second predetermined time interval (TI2), where the magnitude of a second predetermined time interval (TI2) is greater than the magnitude of a first predetermined time interval (TI1). [2] Access arrangement according to claim 1, wherein the verification device (UEI, UEF) upon receiving a further query signal (AF4) by the identifier-side transmit / receive device (SEI) with reduced receive sensitivity, issues a second control command (STB2) to further reduce the receive sensitivity (E) of the identifier-side transmit / receive device by a second predetermined amount (B2). [3] Access arrangement according to claim 2, wherein the verification device (UEI) issues the second control command (STB2) before the expiry of a second predetermined time interval (TI2) upon receipt of a further query signal (AF4) by the identifier-side transmit / receive device (SEI). [4] Access arrangement according to one of claims 1 to 3, wherein the time measuring device (ZME) begins measuring a predetermined second time interval (TI2) after the identifier-side transmitting / receiving device (SEI) has received an interrogation signal (AFX) or after a previous predetermined second time interval (TI2) has elapsed without the identifier-side transmitting / receiving device (SEI) having received an interrogation signal (AFX). [5] Access arrangement according to one of claims 1 to 4, wherein the identifier-side transmit / receive device (SEI) is configured to transmit a response signal (AWX) in response to the reception of one or more query signals (AFX). [6] Access arrangement according to claims 1 and 5, wherein - the timing device (TDD) is designed to measure a third predetermined time interval after receiving a predetermined number of query signals (AFX), and - the identifier-side transmit / receive device (SEI) is designed to send a response signal in response to the reception of the last of the predetermined number of query signals (AFX) and then not to send any further response signal until the end of the third predetermined time interval. [7] Access arrangement according to any one of claims 1 to 6, wherein the verification device (UEI, UEF) after setting the sensitivity (E) of the identifier-side transmit / receive device (SEI) to a predetermined value does not further change the sensitivity until the identifier-side transmit / receive device (SEI) has received a predetermined number of query signals (AFX) and has responded accordingly with a response signal. [8] Access arrangement according to one of claims 1 to 7, wherein the receive sensitivity (E) of the identifier-side transmitting / receiving device is adjustable only to a minimum value. [9] Access arrangement according to any one of claims 1 to 8, wherein the mobile identifier has an identifier-side control unit (STI) for controlling the identifier-side transmit / receive unit in which the verification unit (UEI) is integrated. [10] Access arrangement according to any one of claims 1 to 9, wherein the mobile identifier (IDG) has an identifier-side storage device (SPI) for storing an evaluated field strength of an interrogation signal received by the identifier-side transmit / receive device and / or the receive sensitivity set when receiving the interrogation signal. [11] Access arrangement according to any one of claims 1 to 10, wherein the query signals (AFX) emitted by the vehicle-side transmitting / receiving device have the same and / or constant field strength values. [12] Mobile identification transmitter for an access arrangement for a vehicle, in particular according to one of claims 1 to 11, with an adjustable receive sensitivity (E), which is configured to perform an automatic dynamic adjustment of the receive sensitivity (E) by continuously reducing or increasing the receive sensitivity (E) in order to obtain a value of the receive sensitivity (E) which approximately represents the distance of the mobile identification transmitter to a vehicle, with the following features: - an identifier-side transmitting / receiving device (SEI) with adjustable receive sensitivity (E): for receiving the query signals (AFX) from the vehicle's transmit / receive device, - a verification device (UEI, UEF) for issuing a control command (STB1) to reduce the sensitivity (E) of the identifier-side transmitter / receiver (SEI) by a first predetermined amount (B1) when the identifier-side transmitter / receiver (SEI) has received a predetermined number of query signals (AFX) transmitted by the vehicle-side transmitter / receiver (SEF), and a - Timing device (TD) for measuring predetermined time intervals, which, after the expiry of a second predetermined time interval (TI2), causes the verification device (UEI) to issue a third control command (STB3) to increase the receive sensitivity of the identifier-side transmit / receive device (SEI) by a third predetermined amount (B3) if the identifier-side transmit / receive device (SEI) has not received an interrogation signal (AFX) after the expiry of the second predetermined time interval (TI2), where the magnitude of a second predetermined time interval (TI2) is greater than the magnitude of a first predetermined time interval (TI1). [13] Vehicle (FZ) with an access arrangement (ZA) according to any one of the preceding claims 1 to 11. [14] Method for operating an access order (AE) for a vehicle (FZ) comprising the following steps: Sending multiple query signals (AFX) from the vehicle (FZ) at first predetermined time intervals (TI1); Receiving the query signals (AFX) by at least one mobile identification transmitter (IDG) with adjustable reception sensitivity (E); Automatic dynamic adjustment of the receive sensitivity (E) by the mobile identification transmitter (IDG) by continuously reducing or increasing the receive sensitivity (E) to obtain a receive sensitivity (E) value that approximately represents the distance of the mobile identification transmitter to the vehicle, as follows: Issuing a control command (STBY) to reduce the receive sensitivity (E) of the mobile identifier (IDG) by a first predetermined amount (B1) when the identifier-side transmit / receive device (SEI) has received a predetermined number of query signals (AFX) transmitted by the vehicle-side transmit / receive device (SEF); Output of a third control command (STB3) after the expiry of a second predetermined time interval (TI2) to increase the receive sensitivity of the identifier-side transmit / receive device (SEI) by a third predetermined amount (B3) if the identifier-side transmit / receive device (SEI) has not received an interrogation signal (AFX) after the expiry of the second predetermined time interval (TI2), where the magnitude of a second predetermined time interval (TI2) is greater than the magnitude of a first predetermined time interval (TI1).

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