JP2003008465A - Signal transmission system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a signal transmission system that can identify a mobile transmitter-receiver 20 capable of transmitting a signal to an on-vehicle receiver 10 and transmits a request signal and receives an answer signal to/from the identified mobile transmitter-receiver 20 only. SOLUTION: The signal transmission system is adopted between the on-vehicle transmitter-receiver 10 and a plurality of mobile transmitter-receives 20, in an ordinary operating mode where the on-vehicle transmitter-receiver 10 transmits the request signal to each mobile transmitter-receiver 20 and each mobile transmitter-receiver 20 returns the answer signal, when the on-vehicle transmitter-receiver 10 detects collision of the answer signals, the on-vehicle transmitter-receiver 10 transmits an identification request signal to each mobile transmitter-receiver 20. When receiving return of identification signals in a particular timing preset to each mobile transmitter-receiver 20, the on-vehicle transmitter-receiver 10 shifts to an identification operating mode where the on-vehicle transmitter-receiver 10 admits the mobile transmitter-receiver 20 transmitting the identification signal and sequentially transmits the individual request signal to each admitted mobile transmitter-receiver 20 and receives the answer signal from each admitted mobile transmitter-receiver 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal transmission system, and more particularly, when an in-vehicle transmitter / receiver is used as a portable transmitter / receiver when performing bi-directional signal transmission between an in-vehicle transmitter / receiver and a plurality of portable transmitter / receivers. When a collision of answer signals from the transceiver is detected,
The present invention relates to a signal transmission system that shifts to an operation mode that avoids the collision.

[0002]

2. Description of the Related Art Conventionally, a signal transmission system adopted in a passive keyless entry system is a vehicle-mounted transceiver mounted on an automobile and one or more portable transceivers capable of communicating with the vehicle-mounted transceiver. Is used to perform bidirectional signal transmission by wireless signals between the in-vehicle transceiver and one or more portable transceivers, and control signals are transmitted between the in-vehicle transceiver and the portable transceiver. At that time, the transmitted control signal was used to lock or unlock the automobile door, and in some cases, to start the engine.

In this type of signal transmission system, the frequency of the radio signal transmitted between the on-vehicle transceiver and one or more portable transceivers is from the on-vehicle transceiver to each portable transceiver. A low frequency signal (LF) that can be transmitted only within the close range of the vehicle is used for the transmission of the signal. On the other hand, the transmission of the signal from the portable transceiver to the in-vehicle transceiver can be performed relatively far. Possible high frequency signal (R
F) is used.

In addition, the signal transmission mode in this type of signal transmission system is generally such that a vehicle-mounted transceiver transmits a batch request signal to one or more portable transceivers and receives the batch request signal. A batch transmission / reception operation in which each portable transceiver returns an answer signal to the in-vehicle transceiver is executed. Then, when the on-vehicle transceiver detects that the answer signals returned from the respective portable transceivers collide with each other, all the portable transceivers, that is, one or more portable transceivers have a predetermined order. The individual transmitter / receiver transmits the individual request signal with, and each portable transmitter / receiver receiving the individual request signal addressed to its own portable transmitter / receiver shifts to an individual transmitter / receiver operation in which an answer signal is returned. The individual request signal to the first portable transceiver, the answer signal from the first portable transceiver is returned, and the individual request signal to the second portable transceiver Transmission of individual request signal and reply of answer signal are sequentially executed for each portable transceiver, such as transmission and reply of answer signal from the second portable transceiver. That.

1 of signal transmission in this individual transmission / reception operation
The cycle ends when the vehicle-mounted transceiver transmits an individual request signal to all the portable transceivers and an answer signal is returned in response to the transmission.

[0006]

According to the known signal transmission method, a vehicle-mounted transceiver transmits a batch request signal,
When the in-vehicle transceiver detects a collision of answer signals during the batch transmission / reception operation in which answer signals are returned from the respective portable transceivers, the in-vehicle transceiver will send a response to all portable transceivers as described above. Then, the individual request signal is transmitted in a predetermined order, and the answer signal in response to the individual request signal is returned from each portable transceiver that has received the individual request signal addressed to its own portable transceiver. Move to operation. During such an individual transmission / reception operation, each portable transceiver is not necessarily within the distance range that can receive the individual request signal transmitted from the in-vehicle transceiver, If there is a transceiver, the portable transceiver becomes a non-responsive portable transceiver that cannot receive the individual request signal and cannot send an answer signal in response to the individual request signal. The in-vehicle transmitter / receiver waits for an answer signal to arrive even for such a non-responsive portable transmitter / receiver until a certain period of time elapses. It is determined that the transmitter / receiver is an unresponsive portable transmitter / receiver, and the individual request signal is transmitted to the portable transmitter / receiver in the next order.

As described above, in the known signal transmission method, when the number of unresponsive portable transceivers is relatively large when the individual transmission / reception operation is performed, the arrival waiting time of the answer signal becomes large, and As a result, the time for one cycle of signal transmission is significantly lengthened, and the signal transmission efficiency is reduced.

The present invention has been made in view of the above technical background, and an object thereof is to select an in-vehicle transceiver and a portable transceiver capable of signal transmission, and to select the portable transceiver. It is to provide a signal transmission method for transmitting a request signal and receiving an answer signal.

[0009]

In order to achieve the above object, the signal transmission method according to the present invention is performed between an on-vehicle transceiver and a plurality of portable transceivers, and the on-vehicle transceiver Answer request to the in-vehicle transceiver in the normal operation mode in which a request signal is transmitted from the device to the in-vehicle transceiver, and each portable transceiver that receives the request signal returns an answer signal to the in-vehicle transceiver. When a signal collision is detected, an identification request signal is sent to multiple portable transceivers, and the portable transceivers that receive the identification request signal receive the unique timing preset for each portable transceiver. The identification signal is returned to the in-vehicle transceiver, and the in-vehicle transceiver authenticates the portable transceiver that transmitted the identification signal based on the reception timing of the identification signal. In sequence on the certification was each portable transceiver comprises means to shift to identify the operating mode for receiving the transmit and answer signal of the individual request signals.

According to the above means, when the vehicle-mounted transceiver detects the collision of the answer signals returned from the plurality of portable transceivers in the normal operation mode, the vehicle-mounted transceiver immediately shifts to the identification operation mode and the plurality of portable transceivers. After transmitting the identification request signal to the transceiver, when the portable transceiver that received the identification request signal receives the identification signal returned at the unique timing preset in each portable transceiver, the identification The portable transceiver that has transmitted the identification signal is certified based on the signal reception timing, and individual request signals and answer signals are received in order for each certified portable transceiver, so the There is no waiting time for the answer signal to arrive at the transceiver, and one cycle of signal transmission is not lengthened.

Further, the identification signal in the above means is composed of a single pulse having a narrow width or a single pulse containing ID.

With such a configuration, each portable transceiver can generate an accurate identification signal at a unique timing preset by itself, and the number of portable transceivers is relatively large. Even if the number becomes large, it is possible to easily set the unique timing for each portable transceiver.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of a signal transmission system according to the present invention, and is a block diagram showing the main configuration of a vehicle-mounted transceiver and a portable transceiver. This signal transmission system is passive. It shows an example applied to a keyless entry.

As shown in FIG. 1, the passive keyless entry to which the signal transmission system according to the embodiment is applied is equipped with an on-vehicle transceiver 10 mounted on an automobile (not shown in FIG. 1) and an on-vehicle transceiver 10. It is composed of one or more portable transceivers 20 each owned by the owner and / or their family, and only one portable transceiver 20 is shown in FIG. 1.

In this case, the on-vehicle transceiver 10 includes a control unit (CPU) 1, a storage unit 2 including an EEPROM and the like.
The low frequency signal transmission unit (LF TX) 3, the high frequency signal reception unit (RF RX) 4, the timer 5, the low frequency antenna 6 for transmission, and the high frequency antenna 7 for reception, and the storage unit 2 is portable. has a built-in transceiver identification table 2 _1. In addition, the portable transceiver 20 includes a control unit (CPU) 1
1, a storage unit (memory) 12, a low frequency signal reception unit (LF RX) 13, and a high frequency signal transmission unit (RFTX)
14, timer 15, low-frequency antenna 16 for reception
And a high frequency antenna 17 for transmission.

In the on-vehicle transceiver 10, the control unit 1 is connected to the storage unit 2, the output end of the low frequency signal transmission unit 3, the input end of the high frequency signal reception unit 4, and the timer 5, respectively. The output end of the low-frequency signal transmitter 3 is connected to the low-frequency antenna 6 for transmission, and the input end of the high-frequency signal receiver 4 is connected to the high-frequency antenna 7 for reception. In the portable transceiver 20, the control unit 11 is connected to the storage unit 12, the output end of the low frequency signal receiving unit 13, the input end of the high frequency signal transmitting unit 14, and the timer 15. The input end of the low-frequency signal reception unit 13 is connected to the reception low-frequency antenna 16, and the output end of the high-frequency signal transmission unit 14 is connected to the transmission high-frequency antenna 17.

Next, FIG. 2 is a flow chart showing the signal transmission / reception process executed by the vehicle-mounted transceiver 10 in the signal transmission system of this embodiment shown in FIG.

FIG. 3 is an operation explanatory view showing an example of an operation state when transmitting and receiving a signal in the vehicle-mounted transceiver 10, wherein the upper stage (first stage) is the signal transmission state and the lower stage (2 stages). The eye) indicates the signal reception state.

The operation of the signal transmission system according to this embodiment will be described with reference to the flowchart shown in FIG. 2 and the operation explanatory view shown in FIG.

In each of steps S1 to S12 shown in FIG. 2, steps S1 to S
5 represents the operation when the in-vehicle transceiver 10 is in the normal operation mode, and steps S6 to S12 represent the operation when the in-vehicle transceiver 10 shifts to the identification operation mode.

First, in step S1, the in-vehicle transceiver 10 causes the control unit 1 to form a batch request signal to generate a low frequency signal at a predetermined transmission timing, as shown in the first stage of FIG. The low-frequency signal transmission unit 3 supplies the batch request signal supplied by the low-frequency signal transmission unit 3 to the low-frequency carrier signal, and the low-frequency antenna 6 for transmission as a radio signal.
Send from

The wireless signal transmitted by the on-vehicle transceiver 10 is received by the portable transceiver 20 within the receivable range of the wireless signal. The low-frequency antenna 1 for receiving this wireless signal.
When received by the low frequency signal receiving unit 13 through 6, the batch request signal is reproduced from the radio signal received by the low frequency signal receiving unit 13, and the obtained batch request signal is received by the control unit 1.
Supply to 1. The control unit 11 forms an answer signal in response to the supply of the batch request signal, and supplies the formed answer signal to the high frequency signal transmitting unit 14. The high-frequency signal transmitter 14 puts the supplied answer signal on the high-frequency carrier signal and transmits it as a radio signal from the high-frequency antenna 17 for transmission.

Next, in step S2, when the vehicle-mounted transceiver 10 receives the radio signal transmitted by any of the portable transceivers 20 through the reception radio-frequency antenna 7 at the radio-frequency signal receiving section 4, the radio-frequency signal reception unit 4 receives the radio-frequency signal. The answer signal is reproduced from the high-frequency carrier signal received by the unit 4, and the obtained answer signal is supplied to the control unit 1.

Next, in step S3, the vehicle-mounted transceiver 10 determines whether or not the high-frequency signal receiver 4 is receiving the answer signal from the state in which the answer signal is supplied or not supplied to the controller 1. . When it is determined that the answer signal has already been received (Y), the process proceeds to the next step S4, while when it is determined that the answer signal has not been received (N), the process returns to the first step S1. Again, the operation after step S1 is repeatedly executed.

In the next step S4, the vehicle-mounted transceiver 10 collides with the answer signal transmitted from each portable transceiver 20 based on the supply state of the answer signal to the controller 1. Determine whether or not.
Then, as shown in the second row of FIG. 3, when it is determined that a collision has occurred in the answer signal (Y), the operation mode of the vehicle-mounted transceiver 10 is changed from the normal operation mode to the identification operation mode. Then, the process shifts to another step S6. On the other hand, when it is determined that the answer signal does not collide (N), the process shifts to the next step S5.

Subsequently, in step S5, when the controller 1 formally accepts the answer signal, the on-vehicle transceiver 10 executes control such as unlocking the vehicle door based on the acceptance of the answer signal. . After the answer signal is received, the process returns to the first step S1 and the operations after step S1 are repeatedly executed again.

Further, in step S6, the in-vehicle transceiver 10 changes the operation mode to the identification operation mode, and when the predetermined transmission timing comes, the control unit 1 forms the identification request signal. The low-frequency signal transmitting unit 3 supplies the low-frequency signal transmitting unit 3 with the supplied identification request signal on the low-frequency carrier signal, and at the timing shown in the first stage of FIG. Transmit from the low frequency antenna 6.

At this time, the portable transceiver 20 within the receivable range of the transmitted wireless signal, for example, the two portable transceivers 20 ₃ and 20 within the receivable range of the wireless signal.
_If there were ₇ , two portable transceivers 20 ₃ , 2
0 ₇ receives this radio signal through the receiving low-frequency antenna 16 at the low-frequency signal receiving unit 13, and the low-frequency signal receiving unit 1
3 reproduces the baseband identification request signal from the received signal, and supplies the obtained identification request signal to the control unit 11. The control unit 11 responds to the supply of the identification request signal at a specific transmission timing preset in its own portable transceivers 20 ₃ and 20 ₇ , that is, is supplied from the in-vehicle transceiver 10. When a different time elapses for each portable transceiver 20 from the end of reception of the identification request signal, a narrow single pulse is formed as an identification signal and the single pulse is supplied to the high frequency signal transmitter 14. . The high-frequency signal transmitter 14 puts the supplied single-shot pulse on the high-frequency carrier signal and transmits it as a wireless signal from the transmitting high-frequency antenna 17.

Next, in step S7, the vehicle-mounted transceiver 10 transmits the identification request signal under the control of the control unit 1 and at the same time starts the timer 5 to time.
The setting time of the timer 5 at this time is selected to be a time sufficient for all the portable transceivers 20 to return a single pulse (identification signal) to the transmission of the identification request signal. .

Next, in step S8, the vehicle-mounted transceiver 10 determines whether or not the timed value of the timer 5 has reached the set timed value (timer 5 has timed out) under the control of the control unit 1. . When it is determined that the timed value of the timer 5 has reached the set timed value (Y), the process proceeds to another step S11, while it is determined that the timed value of the timer 5 has not yet reached the set timed value ( If N), the process proceeds to the next step S9.

In step S9, the in-vehicle transmitter / receiver 10 determines whether the high-frequency signal receiving section 4 is one of the portable signals from the state where the narrow single pulse (identification signal) is supplied or not supplied to the control section 1. It is determined whether or not the narrow single pulse (identification signal) transmitted from the transceiver 20 is received. If it is determined that the narrow single pulse (identification signal) has already been received (Y), the following step S10 is performed.
On the other hand, when it is judged that the narrow single pulse (identification signal) has not been received yet (N), the previous step S
Returning to step 8, the operations after step S8 are repeatedly executed again.

Then, in step S10, the vehicle is mounted.
The transceiver 10 controls the timer 5 under the control of the control unit 1.
A narrow single pulse (identification signal) from the timed value to that point
Which portable transceiver is the transmitted / received portable transceiver 20?
20₃, 20₇Identify which is. Ie portable transport
Receiver 20₃, 20₇Are the identification request signals
Is preset in your own portable transceiver from the end of reception.
After a certain period of time has elapsed, a single pulse is sent, so
On the transceiver 10 side, as shown in FIG.
Mobile after each different time from the end of transmission
Transceiver 20 ₃, 20₇Receives a single pulse from
It The in-vehicle transceiver 10 is a portable transceiver
20 and its portable transceiver 20 send a single pulse
Since the relationship with the signal timing is recorded, the identification signal
Time from the end of transmission to the reception of a single pulse (Fig.
The portable transceiver 20 is divided by t1 and t2 in 3).
It can be different. Then, the control unit 1 transmits and receives the portable data.
The transmitters / receivers 20 that identify the
Transceiver 20₃And portable transceiver 20₇Recognized as
If you know, portable transceiver 20₃And portable transceiver 2
0₇Temporary portable transceiver identification table 2₁Stored in
(save. And the portable transceiver identification table 2
₁Portable transceiver 20 to₃And portable transceiver 20₇
Is completed, the process returns to the previous step S8, and the step starts again.
The operations after step S8 are repeatedly executed.

Further, in step S11, the vehicle-mounted transceiver 10, the portable transceiver is stored in the portable transceiver identification table 2 ₁ under the control of the control unit 1 2
0, in this case, it is determined whether or not there are the portable transceiver 20 ₃ and the portable transceiver 20 ₇ . Then, it is judged that there is a portable transceiver 20 stored in the portable transceiver identification table 2 ₁ (Y) the next step S12, when
Proceeds to, whereas, when it is determined that there is no portable transceiver 20 stored in the portable transceiver identification table 2 ₁ (N) is to return the operation mode of the car-mounted transmitter-receiver 10 to the normal operating mode Then, the process returns to the first step S1, and the operations after step S1 are repeatedly executed again.

Then, in step S12, the vehicle-mounted transceiver 10 is controlled by the control unit 1 when the predetermined transmission timing is reached, and the portable transceiver identification table 2 is displayed.
_For the portable transceiver 20 _{3 in the} previous order stored in ₁ , the control unit 1 forms the individual request signal R3 and supplies it to the low frequency signal transmission unit 3, and the low frequency signal transmission unit 3 supplies it. The individual request signal R3 thus generated is placed on the low-frequency carrier signal, and is transmitted as a radio signal from the low-frequency antenna 6 for transmission at the timing shown in the first stage of FIG.

At this time, when the portable transceiver 20 ₃ which is the destination of the individual request signal receives this radio signal through the low frequency antenna 16 for reception by the low frequency signal receiving section 13, the individual base band is received from the received signal. The request signal R3 is reproduced, and the obtained individual request signal R3 is supplied to the control unit 11. The control unit 11 forms the answer signal A3 in response to the supplied individual request signal R3 and supplies the answer signal A3 to the high frequency signal transmission unit 14. The high-frequency signal transmitter 14 puts the supplied answer signal A3 on the high-frequency carrier signal, and when the timing shown in the second stage of FIG.
A radio signal is transmitted from the transmitting high frequency antenna 17.

The on-vehicle transceiver 10 is a portable transceiver 2
The radio signal transmitted from the antenna 0 ₃
When received by the high frequency signal receiving unit 4 through the high frequency signal receiving unit 4, the high frequency signal receiving unit 4 reproduces the answer signal A3 from the received signal and supplies the answer signal A3 to the control unit 1. When confirming the arrival of the answer signal A3, the control unit 1 requests the portable transceiver 20 _{7 in the} next order stored in the portable transceiver identification table 2 _{1 from} the individual request as in the previous case. The signal R7 is formed, placed on a low frequency carrier signal and transmitted as a radio signal to the portable transceiver 20 ₇ . And the portable transceiver 20
_{When 7} receives this radio signal, the portable transceiver 20 ₇
To perform reproduction of the individual request signal R7, formation of an answer signal A7 in response to the individual request signal R7, and wireless transmission of a high frequency carrier signal carrying the answer signal A7, and the in-vehicle transceiver 10 receives and reproduces the answer signal A7. To do. In addition to the two portable transceivers 20 ₃ and 20 _{7 in} the portable transceiver identification table 2 ₁ , if another portable transceiver 20 is stored, all the stored portable transceivers are stored. For 20, the individual request signal is sequentially transmitted and the answer signal is received subsequently.

Then, the portable transceiver identification table 2 ₁
When the transmission of the individual request signal and the subsequent reception of the answer signal to all the portable transceivers 20 stored in are completed, the in-vehicle transceiver 10 changes its operation mode from the identification operation mode to the normal operation mode. Returned to
Returning to the first step S1, the operation after step S1 is repeatedly executed again.

By the way, in the above-mentioned embodiment, the transmission timing of the narrow single pulse (identification signal) preset in each portable transceiver 20 is set to the end point of reception of the identification request signal. Although the description has been given by taking the example of individually setting as a reference, the reference time point of the transmission timing of the narrow single-shot pulse (identification signal) according to the present invention is not limited to such an example, and other You may make it use a reference | standard time.

FIG. 4 is an operation explanatory view showing another example of setting each timing of signal transmission and signal reception in the vehicle-mounted transceiver shown in FIG. 1, and is a narrow single-shot pulse (identification). This is an example in which the transmission timing of (signal) is individually set with reference to the reception end time of the header information.

As shown in FIG. 4, when each portable transceiver 20 returns header information in response to the transmission of the identification request signal and the on-vehicle transceiver 10 receives these header information, The in-vehicle transceiver 10 is
The transmission timing of a narrow single-shot pulse (identification signal) preset in each portable transceiver 20 is set based on the reception end time of the received header information.

FIG. 5 is an operation explanatory diagram showing another example of the configuration of the identification signal transmitted from each portable transceiver shown in FIG.

In the example shown in FIG. 5, instead of using a narrow single pulse as an identification signal, a single pulse containing an ID assigned to each portable transceiver 20 is used. In this way, when the single pulse including the ID is used, the pulse width of each single pulse is slightly widened as compared with the case where the narrow single pulse is used, and the time until all the single pulses are transmitted is wide. It is slightly longer than when using a narrow single pulse,
With the inclusion of, it becomes easy to identify the portable transceiver 20 that transmitted this single-shot pulse.

Next, FIGS. 6 and 7 are a plan view and an explanatory view for explaining the operating state of the vehicle-mounted transceiver 10 shown in FIG. 3 more specifically, and FIG. 6 is at a certain point in time. FIG. 7 is a plan view showing an example of an arrangement relationship between an on-vehicle transceiver and each portable transceiver, and FIG. 7 shows an on-vehicle transceiver at that time point, and an on-vehicle transceiver and a portable transceiver capable of signal transmission. It is explanatory drawing which shows an example of the signal transmission timing performed between these.

In the example shown in FIGS. 6 and 7, automatic
There are six portable units for the in-vehicle transceiver 10 mounted on the vehicle 8.
Band transceiver 20₁Through 20₆Can be used
In addition, these six portable transceivers 20₁Through 20
₆On the other hand, as shown in FIG.
The close range of the vehicle 8 equipped with the in-vehicle transceiver 10
Within the remote range, that is, transmitted from the in-vehicle transceiver 10
Range of low-frequency wireless signals (denoted by symbol E)
3 portable transceivers 20 inside₁, 20₃, 20 ₆Is distributed
However, if the vehicle 8 is out of the close range,
Low frequency radio signal transmitted from the in-vehicle transceiver 10
Outside the reachable range E of the three portable transceivers 20₂Two
0_Four, 20_FiveAre arranged.

FIG. 7 shows that when the on-vehicle transceiver 10 and the six portable transceivers 20 _{1 to} 20 ₆ are arranged in the state shown in FIG. FIG. 3 is an explanatory diagram showing an example of signal transmission timings performed between the _three portable transceivers 20 ₁ , 20 ₃ , and 20 ₆ which are in a signal transmissible state.
The tiers show the signal transmission state and the signal reception state in the in-vehicle transceiver 10, respectively, and the tiers 3 and 4 show the signal reception state and the signal transmission state in the portable transceiver 20 _1, respectively. The fifth and sixth stages show the signal reception state and the signal transmission state of the portable transceiver 20 _3, respectively, and the seventh and eighth stages show the signal reception state and the signal of the portable transceiver 20 ₆ , respectively. It shows a transmission state.

Hereinafter, with reference to the explanatory view of FIG.
Machine 10 and three portable transceivers 20 ₁, 20₃, 20₆
The state of signal transmission performed between and will be described.

First, as shown in the first row, when the vehicle-mounted transceiver 10 transmits a batch request signal, as shown in the third, fifth, and seventh rows, the portable transceiver Machines 20 ₁ , 20 ₃ and 20 ₆ are in-vehicle transceivers 1
0 to receive the batch request signal from each, and in response to the batch request signal, the portable transceiver 20 ₁ ,
20 ₃ and 20 ₆ transmit answer signals as shown in the fourth, sixth, and eighth stages, respectively. Since the transmission timings of these answer signals are almost coincident with each other, as shown in the second stage, when these answer signals are received by the vehicle-mounted transceiver 10, the answer signals overlap each other. The machine 10 detects the collision of the answer signal, and the operation mode of the in-vehicle transceiver 10 shifts from the normal operation mode to the identification operation mode.

Next, as shown in the first row, when the on-vehicle transceiver 10 transmits the identification request signal, as shown in the third, fifth and seventh rows respectively, The transceivers 20 ₁ , 20 ₃ , and 20 ₆ are in-vehicle transceivers 1.
Each of the portable transceiver 20 receives the identification request signal from 0 and responds to the identification request signal.
₁ , 20 ₃ and 20 ₆ are, as shown in the 4th, 6th and 8th stages respectively, their own portable transceivers 20 ₁ , 2
The identification signals 1, 3, and 6 are transmitted at timings preset to 0 ₃ and 20 ₆ , that is, after different times have elapsed from the transmission end time of the identification request signal in the vehicle-mounted transceiver 10. . When the vehicle-mounted transceiver 10 receives the identification signals 1, 3, and 6, the arrival times of the identification signals 1, 3, and 6 are different, and the arrival times are different, as shown in the second stage. Since the portable transceivers 20 ₁ , 20 ₃ and 20 ₆ are unique to the in-vehicle transceiver 10,
From the arrival time of 3 and 6, it is identified from which portable transceivers 20 ₁ , 20 ₃ and 20 ₆ the identification signals ₁ , ₃ and ₆ are transmitted, and the identified portable transceivers 20 ₁ and Two
0 ₃ and 20 ₆ are temporarily stored in the portable transceiver identification table 2 ₁ .

Then, as shown in the first row,
The transceiver 10 is a portable transceiver 20. ₁Individual request addressed to
When the strike signal 1 is transmitted, the third, fifth, and seventh stages are transmitted.
As shown in each, a portable transceiver 20₁, 20
₃, 20₆Is an individual request from the in-vehicle transceiver 10
Each receives signal 1. At this time, the portable transceiver
20₁Is the individual request signal 1 addressed to itself,
In response to this individual request signal 1, it is shown in the fourth row.
To send answer signal 1, but for portable transmission and reception
Machine 20₃, 20₆Is an individual request signal 1 addressed to itself
Since it does not respond to this individual request signal 1,
Do not send answer signal at time. Therefore, in the second stage
As shown, the on-vehicle transceiver 10 outputs the answer signal 1
A portable transceiver 20 that only receives₁Individual request for
Transmission of Est signal 1 and portable transceiver 20₁From
The reception of the sensor signal 1 ends.

After this, as shown in the first row,
The transceiver 10 is a portable transceiver 20. ₃Individual request addressed to
When the strike signal 3 is transmitted, the third, fifth, and seventh stages are transmitted.
As shown in each, a portable transceiver 20₁, 20
₃, 20₆Is an individual request from the in-vehicle transceiver 10
Each receives signal 3. At this time, the portable transceiver
20₃Is the individual request signal 3 addressed to itself, so
In response to this individual request signal 3, it is shown in the sixth row.
To send answer signal 3 as
Machine 20₁, 20₆Is an individual request signal 3 addressed to self
Since it does not respond to this individual request signal 3,
Do not send answer signal at time. Therefore, in the second stage
As shown, the vehicle-mounted transceiver 10 sends the answer signal 3
A portable transceiver 20 that only receives₃Individual request for
Transmission of Est signal 3 and portable transceiver 20₃From
The reception of the sensor signal 3 ends.

Then, when the vehicle-mounted transceiver 10 transmits the individual request signal 6 addressed to the portable transceiver 20 ₆ ,
As in the previous case, only the portable transceiver 20 ₆ transmits the answer signal 6 and the in-vehicle transceiver 10 receives this answer signal 6 and transmits the individual request signal 6 to the portable transceiver 20 ₆ . And the reception of the answer signal 6 from the portable transceiver 20 ₆ ends. This point, portable transceiver identification table 2 portable transceiver which is stored in the ₁ 20 _1, 20 _3, 20 ₆ individual request signals for each of transmission and their portable transceiver 2
Since the answer signals from 0 ₁ , 20 ₃ and 20 ₆ are received _once , the in-vehicle transceiver 10 returns from the identification operation mode to the normal operation mode, and thereafter, the above-described operation is repeatedly executed. .

As described above, according to these embodiments, when the vehicle-mounted transceiver 10 detects the collision of the answer signal in the normal operation mode, the vehicle-mounted transceiver 10 discriminates the operation mode from the normal operation mode. Mode,
The portable transceiver 20 capable of signal transmission is identified by transmitting the identification request signal and receiving the identification signal in response thereto, and transmitting the individual request signal only to the identified portable transceiver 20 and answering thereto Since the signal is received, the in-vehicle transceiver 1
There is no waiting time for the answer signal to arrive at 0,
One cycle of signal transmission does not become long.

In each of the above embodiments, the signal transmission method is applied to the passive keyless entry, but the signal transmission method according to the present invention is not limited to the passive keyless entry. ,
Of course, it can be applied to the one similar to the passive keyless entry.

[0055]

As described above, according to the present invention, when the vehicle-mounted transceiver detects a collision of answer signals returned from a plurality of portable transceivers in the normal operation mode, it immediately enters the identification operation mode. After transmitting and transmitting the identification request signal to multiple portable transceivers, the portable transceivers that received the identification request signal reply at the specific timing preset in each portable transceiver. When the received identification signal is received, the portable transceiver that has transmitted the identification signal is certified based on the reception timing of the identification signal, and the individual request signal is transmitted and the answer is sent in turn to each certified portable transceiver. Since signals are being received, there is no waiting time for the answer signal to arrive in the on-vehicle transceiver, and one cycle of signal transmission can be lengthened. Kuna' Te, there is an effect that signal transmission efficiency is greatly increased.

[Brief description of drawings]

FIG. 1 shows one embodiment of a signal transmission system according to the present invention, and is a block diagram showing a main part configuration of a vehicle-mounted transceiver and a portable transceiver.

FIG. 2 is a flowchart showing an operation history executed by a vehicle-mounted transceiver in the signal transmission system of this embodiment shown in FIG.

FIG. 3 is a flowchart showing a signal transmission / reception process executed by a vehicle-mounted transceiver in the signal transmission system of this embodiment shown in FIG.

FIG. 4 is an operation explanatory diagram showing another example of setting each timing of signal transmission and signal reception in the vehicle-mounted transceiver shown in FIG. 1.

5 is an operation explanatory diagram showing another configuration example of the identification signal transmitted from each portable transceiver shown in FIG. 1. FIG.

FIG. 6 is a plan view showing an example of a positional relationship between an on-vehicle transceiver and each portable transceiver at a certain time point.

FIG. 7 is an explanatory diagram showing an example of signal transmission timing performed between an in-vehicle transceiver and a portable transceiver capable of signal transmission with the in-vehicle transceiver.

[Explanation of Codes] 1, 11 control unit (CPU) 2, 12 storage unit (EEPROM) 2 ₁ portable transceiver identification table 3 low frequency signal transmission unit (LF TX) 4 high frequency signal reception unit (RF RX) 5, 15 timer 6 low-frequency antenna for transmission 7 high-frequency antenna for reception 8 automobile 10 vehicle-mounted transceiver 13 low-frequency signal receiver (LF RX) 14 high-frequency signal transmitter (RF TX) 16 low-frequency antenna for reception 17 high-frequency antenna for transmission 20, 20 _{1 to} 20 ₆ Portable transceiver

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H04Q 9/00 331 H04Q 9/00 341B 341 H04B 7/26 HF term (reference) 2E250 AA21 BB08 BB25 BB48 BB53 CC20 DD06 EE02 FF23 FF27 FF36 HH01 JJ00 JJ03 KK03 LL00 LL01 SS11 TT03 5K011 EA05 GA03 JA01 KA15 5K048 BA42 BA52 DB01 DC01 EB02 EB03 FC03 GB05 HA04 HA06 5K067 AA13 BB28 DD17 H23DD24 DD24

Claims (6)

[Claims] 1. A signal transmission method performed between an in-vehicle transceiver and a plurality of portable transceivers, wherein a request signal is transmitted from the in-vehicle transceiver to the portable transceiver and the request signal is transmitted. In the normal operation mode in which an answer signal is returned from each of the portable transceivers that have received an answer signal to the in-vehicle transceiver, when the in-vehicle transceiver detects a collision of the returned answer signals, the plurality of portable transceivers are received. The identification request signal is transmitted to, and the portable transceiver that receives the identification request signal returns an identification signal to the in-vehicle transceiver at a unique timing preset in each portable transceiver, The in-vehicle transceiver certifies the portable transceiver that has transmitted the identification signal based on the reception timing of the identification signal, and certifies each portable A signal transmission method characterized by shifting to an identification operation mode in which an individual request signal is sequentially transmitted to a transceiver and an answer signal is received. 2. The signal transmission system according to claim 1, wherein the identification signal is a single pulse having a narrow width. 3. The signal transmission system according to claim 1, wherein the identification signal is a single-shot pulse including an ID unique to a vehicle-mounted transceiver. 4. The determination of the reception timing of the identification signal in the vehicle-mounted transceiver is a determination based on the time from the transmission of the identification request signal. Signal transmission method described in. 5. The determination of the reception timing of the identification signal in the in-vehicle transceiver is performed at the time from the reception of the header information returned by each portable transceiver in response to the transmission of the identification request signal. 4. The signal transmission method according to claim 1, wherein the determination is based on. 6. The identification mode of operation when the vehicle-mounted transceiver sequentially transmits an individual request signal and receives an answer signal to each portable transceiver that is authorized to transmit the identification signal. 6. The signal transmission method according to claim 1, wherein the normal operation mode is restored from the signal transmission method.