JP2012184608A - Keyless entry device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a keyless entry device which can reliably perform transmission and reception of signals according to a condition in communication.SOLUTION: A portable machine 1 includes an operation unit 11 for performing transmission instruction of portable machine transmission signals and a noise measurement unit 19 for measuring the noise level of frequency band used in transmission of vehicle side transmission signals when operation of the operation unit 11 is performed, and a vehicle side device 2 includes a vehicle side control unit for acquiring information on the noise level measured by the noise measurement unit 19 from portable machine transmission signals and for performing transmission control of vehicle side transmission signals based on the acquired information on the noise level.

Description

  The present invention relates to a keyless entry device that locks and unlocks a vehicle door by performing wireless communication between a vehicle side device and a portable device, and more particularly, a keyless device that performs signal transmission control according to a noise level measured by the portable device. It relates to the entry device.

  2. Description of the Related Art Conventionally, a keyless entry device that performs wireless communication between a vehicle-side device provided in a vehicle and a portable device carried by a user and locks / unlocks the door of the vehicle is known. Among these, a keyless entry device is widely used in which a signal is transmitted from the portable device in accordance with an active operation for operating an operation unit provided in the portable device, and a predetermined control is performed when the vehicle receives this signal and authentication is established. It has been.

  In such a keyless entry device, wireless communication between the vehicle side device and the portable device needs to be reliably performed, but when the noise level of the frequency band used for signal transmission is high, the signal cannot be reliably received. There is. For this purpose, a plurality of transmission / reception channels used for communication between the vehicle-side device and the portable device are set, the vehicle-side device periodically detects a noise level, and a signal indicating a transmission / reception channel having a low noise level is transmitted to the portable device. A technique is known in which a signal is transmitted from a portable device using a transmission / reception channel having a low noise level obtained from a vehicle-side device. An example of such a keyless entry device is disclosed in Patent Document 1.

JP 2008-101344 A

  However, the keyless entry device using the transmission / reception channel having a low noise level as described above needs to detect the noise level periodically by the vehicle side device. In addition, the noise level changes at the time of actual communication and when the noise level is measured by the vehicle-side device, and the noise level may increase in a frequency band different from that at the time of measurement. Sometimes it was not done reliably. If the noise level detection interval is reduced in order to reduce this problem, there is a problem that power consumption increases.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a keyless entry device that can reliably transmit and receive signals according to the situation during communication.

In order to solve the above problems, a keyless entry device according to the present invention includes a vehicle-side device and a portable device that perform wireless communication with each other, and the portable device transmits a portable device transmission signal to the vehicle-side device. And a portable device transmitting / receiving unit that receives a vehicle-side transmission signal from the vehicle-side device, and the vehicle-side device receives the portable device transmission signal from the portable device and receives the portable device transmission signal In a keyless entry device having a vehicle-side transmission / reception unit that transmits a vehicle-side transmission signal to a portable device,
The portable device includes an operation unit that instructs transmission of the portable device transmission signal, and a noise measurement unit that measures a noise level of a frequency band used for transmitting the vehicle-side transmission signal when the operation unit is operated. And
The vehicle side device acquires information on a noise level measured by the noise measuring unit from the portable device transmission signal, and performs transmission control of the vehicle side transmission signal based on the acquired noise level information. It is characterized by having a control unit.

  In the keyless entry device according to the present invention, the vehicle-side control unit transmits the vehicle-side transmission signal to the vehicle-side transmission / reception unit when the noise level measured by the noise measurement unit is equal to or higher than a predetermined level. Control is made to increase the output.

  Furthermore, in the keyless entry device according to the present invention, when the noise level measured by the noise measurement unit is equal to or higher than a predetermined level, the vehicle side control unit transmits a bit of the vehicle side transmission signal to the vehicle side transmission / reception unit. Control is made to lower the rate.

In the keyless entry device according to the present invention, the portable device transmission / reception unit and the vehicle-side transmission / reception unit have a plurality of transmission / reception channels corresponding to a plurality of frequency bands, and the noise measurement unit is connected to the plurality of transmission / reception channels. Measure the noise level of each corresponding frequency band,
The vehicle-side control unit is configured to control the vehicle-side transmission / reception unit so that the transmission / reception channel having the lowest noise level measured by the noise measurement unit is preferentially used. .

The keyless entry device according to the present invention includes a vehicle-side device and a portable device that perform wireless communication with each other, and the portable device includes a portable device transmission unit that transmits a portable device transmission signal to the vehicle-side device. And the vehicle-side device has a vehicle-side receiving unit that receives a portable device transmission signal from the portable device,
The portable device includes an operation unit that instructs transmission of the portable device transmission signal, and a noise measurement unit that measures a noise level of a frequency band used for signal transmission when the operation unit is operated, The portable device includes a portable device control unit that performs transmission control of the portable device transmission signal according to a noise level measured by the noise measurement unit.

  Furthermore, in the keyless entry device according to the present invention, the portable device control unit transmits the portable device transmission signal to the portable device transmission unit when the noise level measured by the noise measurement unit is a predetermined level or more. It is characterized by controlling to increase the number of times.

Furthermore, in the keyless entry device according to the present invention, the portable device transmission unit and the vehicle-side reception unit have a plurality of transmission channels corresponding to a plurality of frequency bands, and the noise measurement unit has the plurality of transmission channels. Measure the noise level of each frequency band corresponding to
The portable device control unit is configured to control the portable device transmission unit to preferentially use a transmission channel having the lowest noise level measured by the noise measurement unit. .

  According to the keyless entry device according to the present invention, the portable device has a noise measurement unit that measures a noise level of a frequency band used for transmission of a vehicle-side transmission signal when the operation unit is operated, The device performs the transmission control of the vehicle-side transmission signal according to the noise level measured by the noise measurement unit of the portable device, so that the noise level immediately before transmitting the portable device transmission signal from the portable device is determined immediately after the transmission. Since it can be reflected in the vehicle-side transmission signal that the portable device will receive, the signal can be reliably transmitted and received according to the situation during communication.

  Further, according to the keyless entry device according to the present invention, the portable device transmits the portable device from the portable device by performing transmission control of the portable device transmission signal according to the noise level measured by the noise measurement unit of the portable device. Since the noise level immediately before transmitting the signal can be reflected in the portable device transmission signal transmitted from the portable device, reliable signal transmission / reception according to the situation during communication can be performed.

It is a block diagram of the keyless entry device in this embodiment. It is a time chart of signal transmission when there is operation of an operation part with a portable machine, when a noise level is low in the 1st example. It is a time chart of signal transmission when there is operation of an operation part with a portable machine, when a noise level is high in the 1st example. It is a time chart of signal transmission when there is operation of an operation part with a portable machine, when a noise level is high in the 2nd example. It is a time chart of signal transmission when there is operation of an operation part with a portable machine, when a noise level is high in the 3rd example. It is a time chart of signal transmission when there is operation of an operation part with a portable machine, when a noise level is high in the 4th example.

  Embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a block diagram of a keyless entry device according to the present embodiment. FIG. 1A is a block diagram of the portable device 1, and FIG. 1B is a block diagram of the vehicle-side device 2. The keyless entry device according to the present embodiment includes a vehicle-side device 2 provided in a vehicle and a portable device 1 carried by a user, and performs wireless communication between the vehicle-side device 2 and the portable device 1. Is what you do. Here, a signal transmitted from the portable device 1 to the vehicle side device 2 is referred to as a portable device transmission signal, and a signal transmitted from the vehicle side device 2 to the portable device 1 is referred to as a vehicle side transmission signal.

  The portable device 1 includes a control unit 10 that performs various controls, an operation unit 11 that is operated by a user, and a display unit 12 that displays information to the user. The operation unit 11 is provided with a plurality of switches. For example, one switch instructs unlocking of the door in the vehicle, and the other switch instructs various functions such as locking the door in the vehicle. it can. Note that the operation unit 11 may be a switch, and a locking instruction and an unlocking instruction may be alternately performed each time the operation is performed.

  In addition, the portable device 1 is provided with an antenna 1a that transmits a portable device transmission signal and receives a vehicle-side transmission signal, and a portable device transmission / reception unit 1b that causes the antenna 1a to transmit and receive signals under the control of the control unit 10. ing. The portable device transmitting / receiving unit 1b is provided with an oscillator 13 that oscillates a signal under modulation control, and a transmission / reception channel switching circuit 14 that changes a frequency in the oscillator 13 to switch a plurality of transmission / reception channels. The transmission / reception channel switching circuit 14 is controlled by the control unit 10, and in this embodiment, two transmission / reception channels (transmission / reception channel 1 and transmission / reception channel) having different frequency bands used for transmission of portable device transmission signals and reception of vehicle-side transmission signals are used. 2) can be switched.

  The antenna 1a is connected to a switch 15 constituting the portable device transmitting / receiving unit 1b. The switch 15 is connected to each of a transmission amplifier 16 and a reception amplifier 17 provided in the portable device transmission / reception unit 1b, and switches the connection state between them and the antenna 1a under the control of the control unit 10. When the switch 15 connects the antenna 1a to the transmission amplifier 16, a portable device transmission signal is transmitted from the antenna 1a. On the other hand, when the switch 15 connects the antenna 1a to the reception amplifier 17, the antenna 1a receives the vehicle-side transmission signal. A reception circuit 18 is connected to the reception amplifier 17, and a vehicle-side transmission signal can be received and transmitted to the control unit 10 through a transmission / reception channel set by the transmission / reception channel switching circuit 14 and the oscillator 13.

  In addition, a noise level measurement unit 19 is connected to the reception circuit 18. The noise level measurement unit 19 acquires the RSSI value of noise in the frequency band corresponding to the set transmission / reception channel in the reception state where the vehicle side transmission signal is not received, and uses this as noise level information to the control unit 10. Can pass.

  When the portable device 1 having such a configuration is operated in the operation unit 11, the control unit 10 enters the activated state from the sleep state, and subsequently measures the noise level as described above with the portable device 1 in the reception state. The control unit 10 controls the transmission / reception channel switching circuit 14, the oscillator 13, and the switch 15 to transmit the portable device transmission signal from the antenna 1a while switching the transmission / reception channel. Further, when a portable device transmission signal is transmitted from the portable device 1, a vehicle side transmission signal is transmitted from the vehicle side device 2, and therefore the control unit 10 switches the transmission / reception channel at the timing when the vehicle side transmission signal is transmitted. The circuit 14, the oscillator 13, and the switch 15 are controlled so that the receiving circuit 18 receives the vehicle-side transmission signal via the antenna 1 a while switching the transmission / reception channel.

  The vehicle-side device 2 includes a control unit 20 that performs various controls, and the control unit 20 is connected to other devices 22 in the vehicle via an in-vehicle communication system 21. Moreover, the vehicle side apparatus 2 is provided with the antenna 2a and the vehicle side transmission / reception part 2b. The configuration of the vehicle side transmission / reception unit 2b is substantially the same as that of the portable device transmission / reception unit 1b. The oscillator 23, transmission / reception channel switching circuit 24, switch 25, transmission amplifier 26, reception amplifier 27, reception circuit 28, noise level measurement unit 29 It has. On the other hand, the vehicle side transmission / reception unit 2b differs from the portable device transmission / reception unit 1b in the circuit configuration because the transmission amplifier 26 is connected to the control unit 20 and the transmission output of the vehicle side transmission signal by the control unit 20 can be changed. It is the point comprised so that.

  In the vehicle side device 2, the control unit 20 controls the transmission / reception channel switching circuit 24, the oscillator 23, and the switching unit 25 to intermittently receive the portable device transmission signal to the reception circuit 28 via the antenna 2 a while switching the transmission / reception channel. Let When the portable device transmission signal is received, the control unit 20 controls the transmission / reception channel switching circuit 24, the oscillator 23, and the switch 25 to transmit the vehicle-side transmission signal from the antenna 2a while switching the transmission / reception channel.

  Signal transmission / reception between the portable device 1 and the vehicle-side device 2 in the first embodiment will be described. FIG. 2 shows a signal transmission time chart when the operation unit 11 is operated on the portable device 1 when the noise level is low in the first embodiment. The uppermost part of the figure shows time steps, and each time step is numbered for convenience. The same applies to the subsequent figures.

  In this embodiment, when the operation unit 11 of the portable device 1 is operated, the portable device 1 transmits a portable device transmission signal including a unique identification code, information for instructing an operation, and the like. The received vehicle-side device 2 performs authentication processing, performs a predetermined operation such as unlocking the door when authentication is established, and transmits a vehicle-side transmission signal including information indicating that the predetermined operation has been performed. The portable device 1 that has received this vehicle-side transmission signal displays on the display unit 12 that a predetermined operation has been performed. This entire operation is common to the first to third embodiments.

  First, the vehicle-side device 2 can receive the portable device transmission signal intermittently as described above. In FIG. 2, the signal of the transmission / reception channel 1 can be received from time step 1 to time step 2, and then the signal of the transmission / reception channel 2 can be received from time step 2 to time step 3. The signal on the transmission / reception channel 1 can be received thereafter from time step 5 to time step 6, and the signal on the transmission / reception channel 2 can be received from time step 6 to time step 7. Until the portable device transmission signal is received, the transmission / reception channel 1 signal and the transmission / reception channel 2 signal can be intermittently received at regular intervals.

  In the vehicle side device 2, after the signal of the transmission / reception channel 1 and the signal of the transmission / reception channel 2 are made receivable, the noise level measurement unit 29 measures the noise level of the transmission / reception channel 1, and subsequently the noise level of the transmission / reception channel 2 is also measured. taking measurement. The measurement of the noise level is performed every time after the signal of the transmission / reception channel 1 and the signal of the transmission / reception channel 2 can be intermittently received, and the data is updated and stored in the control unit 20, respectively. Thereby, in the vehicle side apparatus 2, the information of the noise level when it will be in the latest receivable state from the time of receiving a portable device transmission signal will be memorize | stored.

  In FIG. 2, it is assumed that the operation unit 11 of the portable device 1 is operated from time step 2 to time step 3. Thereafter, in the portable device 1, the noise level measurement unit 19 measures the noise level for the transmission / reception channel 1 and the noise level for the transmission / reception channel 2. Information on the noise level of each transmission / reception channel is stored in the control unit 10. Further, the control unit 10 determines whether or not the noise level of each transmission / reception channel is equal to or higher than a predetermined level. In the example of FIG. 2, it is assumed that the noise level is lower than a predetermined level for the frequency band of any transmission / reception channel.

  When the noise level is measured, the portable device transmission signal is transmitted from the time step 8 to the time step 14 using the transmission / reception channel 1. In transmitting the portable device transmission signal, only the carrier wave is output first, and the modulation control is performed by the control unit 10 with a slight delay, and transmission as a data signal is performed. In addition, the portable device transmission signal transmits a data signal a plurality of times within the transmission time, and has a length that enables signal reception reliably in the reception cycle of the vehicle-side device 2, and at least for one time. The data signal can be received. The transmission of such a data signal is the same in the subsequent transmission of the portable device transmission signal and the vehicle-side transmission signal.

  When the portable device transmission signal is transmitted using the transmission / reception channel 1, the portable device transmission signal is transmitted using the transmission / reception channel 2 from time step 15 to time step 21. Here, the portable device transmission signal transmitted using the transmission / reception channel 1 and the transmission / reception channel 2 includes noise level information for each transmission / reception channel measured by the portable device 1.

  In the example of FIG. 2, since any of the transmission / reception channels has a low noise level, the vehicle-side device 2 first transmits / receives the transmission / reception channel 1 transmitted from the portable device 1 at the timing of time step 9 at which the transmission / reception channel 1 can be received. Start receiving portable device transmission signals using. In the vehicle-side device 2, when the control unit 10 controls the reception of the received channel when the signal can be received on the predetermined channel, the portable device transmission signal is received over the time step 14 and is received at least once. The data signal is received.

  The vehicle-side device 2 that has received the portable device transmission signal performs a predetermined operation based on a command included in the data signal and transmits the vehicle-side transmission signal when authentication is established as described above. First, a vehicle-side transmission signal is transmitted from time step 22 to time step 28 using the transmission / reception channel 1, and then a vehicle-side transmission signal is transmitted from time step 29 to time step 35 using the transmission / reception channel 2. In the portable device 1, after transmitting the data signal at time step 21, the transmission mode is immediately switched to the reception mode of the transmission / reception channel 1 and transmission / reception channel 2 as in the vehicle side. Information received and displayed on the display unit 11 is included in the vehicle-side transmission signal. This operation is common to the first to third embodiments.

  If the noise level measured by the portable device 1 is low, the keyless entry device operates as described above. The operation when the noise level is low is the same in other embodiments. On the other hand, when the noise level is high in any of the transmission / reception channels, the operation is as follows. FIG. 3 shows a time chart of signal transmission when the operation unit 11 is operated on the portable device 1 when the noise level of the transmission / reception channel 1 is high in the first embodiment.

  As shown in FIG. 3, when the operation unit 11 is operated on the portable device 1, the noise level measurement unit 19 measures each of the transmission / reception channel 1 and the transmission / reception channel 2 in the same manner as in FIG. The portable device transmission signal is transmitted sequentially using the transmission / reception channel 1 and the transmission / reception channel 2. Here, it is assumed that the noise level is a predetermined level or higher in the frequency band of the transmission / reception channel 1 within a predetermined range including the portable device 1 and the vehicle-side device 2.

  As in the case of FIG. 2, the vehicle-side device 2 is in a state in which a portable device transmission signal can be received for the transmission / reception channel 1 and the transmission / reception channel 2 at a constant cycle. Cannot receive a portable device transmission signal using the transmission / reception channel 1 from. Since the transmission / reception channel 2 has a low noise level, the vehicle-side device 2 receives the portable device transmission signal from time step 18 to time step 21 which is the reception timing of the transmission / reception channel 2. As described above, the time length from time step 18 to time step 21 is a time during which data necessary for reception can be received at least once.

  The portable device transmission signal received by the vehicle-side device 2 includes information indicating that the noise level for the transmission / reception channel 1 is not less than a predetermined level as described above. As described above, when the noise level measured by the portable device 1 in any of the transmission / reception channels is equal to or higher than the predetermined level, the control unit 20 of the vehicle-side device 2 is switched to increase the transmission output of the vehicle-side transmission signal ( Time steps 22-23). Then, in a state where the transmission output is increased, the vehicle side transmission signal is transmitted using the transmission / reception channel 1, and then the vehicle side transmission signal is transmitted using the transmission / reception channel 2.

  In the portable device 1, since the transmission output of the vehicle-side transmission signal is large, the transmission / reception channel 1 and the transmission / reception channel 2 can receive signals even when the noise level is large. If the vehicle-side transmission signal is received, the portable device 1 causes the display unit 11 to display information included in the vehicle-side transmission signal. The vehicle-side transmission signal includes information on the noise level measured by the vehicle-side device 2 and can be displayed on the display unit 11 of the portable device 1 to the effect that the noise level is high.

  As described above, the transmission control is performed by the control unit 20 so as to increase the transmission output of the vehicle-side transmission signal transmitted from the vehicle-side device 2 based on the noise level information acquired when the operation unit 11 is operated by the portable device 1. By performing the above, reliable signal transmission / reception can be performed according to the situation when communication is actually performed between the portable device 1 and the vehicle-side device 2. In particular, the signal transmission of this embodiment is effective when there is an interference wave or the like that causes noise near the portable device.

  Next, signal transmission / reception between the portable device 1 and the vehicle-side device 2 in the second embodiment will be described. FIG. 4 shows a signal transmission time chart when the operation unit 11 is operated on the portable device 1 when the noise level of the transmission / reception channel 1 is high in the second embodiment. In this figure, since the portable device 1 transmits the portable device transmission signal and the vehicle side device 2 receives the portable device transmission signal through the transmission / reception channel 2, it is the same as the case of FIG. .

  The vehicle-side device 2 can determine that the noise level in the transmission / reception channel 1 is greater than or equal to a predetermined level based on the noise level information included in the received portable device transmission signal. In this case, the vehicle-side device 2 lowers the bit rate of the vehicle-side transmission signal and changes the signal transmission order so that the transmission / reception channel with a low noise level is prioritized. That is, first, from time step 22 to time step 28, a low bit rate vehicle-side transmission signal is transmitted using the transmission / reception channel 2, and from time step 29 to time step 35, a low bit rate vehicle is transmitted using the transmission / reception channel 1. Send the side transmission signal.

  The portable device 1 determines that the noise level in the transmission / reception channel 1 is equal to or higher than a predetermined level by measuring the noise level in the noise level measurement unit 19. In this case, reception of the vehicle-side transmission signal at a low bit rate is performed. Corresponding to And since the vehicle side transmission signal is first transmitted from the vehicle side apparatus 2 using the transmission / reception channel 2 with a low noise level, it is controlled by the control part 10 to receive this. Subsequently, the vehicle side transmission signal using the transmission / reception channel 1 is also received.

  As described above, when transmitting a vehicle-side transmission signal from the vehicle-side device 2, a transmission / reception channel having a low noise level is preferentially used based on the information on the noise level measured by the portable device 1. Thus, since the possibility that the measured noise level has changed at the time of reception is lessened, the vehicle-side transmission signal transmitted earlier can be received more reliably by the portable device 1, and the time required for communication can be reduced. Can be reduced. Furthermore, the time until display on the display unit 12 can be shortened. Further, by transmitting the vehicle-side transmission signal at a lower bit rate, it can be made less susceptible to noise when demodulating the signal, and the portable device 1 can receive the vehicle-side transmission signal more reliably. Can do.

  Next, signal transmission / reception between the portable device 1 and the vehicle-side device 2 in the third embodiment will be described. FIG. 5 shows a signal transmission time chart when the operation unit 11 is operated on the portable device 1 when the noise level of the transmission / reception channel 1 is high in the third embodiment. In this figure, since the portable device 1 measures the noise level and the vehicle side device 2 can receive the portable device transmission signal intermittently, it is the same as in FIG. .

  In this embodiment, it is measured that the noise level of the transmission / reception channel 1 is high in the portable device 1. In this case, the portable device transmission signal transmitted from the portable device 1 is transmitted over a longer time, and the number of transmissions is increased accordingly. Specifically, signal transmission using the transmission / reception channel 1 is performed from time step 8 to time step 14 in the case of FIG. 2 where the noise level is low, whereas in FIG. 5 where the noise level is high. Is performed from time step 8 to time step 19. By increasing the number of data transmissions, the probability that any data can be received by the vehicle-side device 2 can be increased.

  Similarly, the transmission of the portable device transmission signal using the transmission / reception channel 2 is lengthened to increase the number of signal transmissions. In the example of FIG. 5, the vehicle-side device 2 receives the portable device transmission signal transmitted using the transmission / reception channel 2 at time step 26. The vehicle-side transmission signal from the vehicle-side device 2 is also made longer than when the noise level is low, the number of signal transmissions is increased, and the bit rate is lowered as in the second embodiment, so that the transmission / reception channel 1 and transmission / reception are performed. Signals are transmitted in the order of channel 2.

  Thus, when the noise level is high, the number of signal transmissions is increased both when transmitting the portable device transmission signal from the portable device 1 and when transmitting the vehicle side transmission signal from the vehicle side device 2. Thus, the probability of signal reception can be increased, and more reliable communication can be performed. In this embodiment, since the transmission control is changed when the noise level is high for both the portable device transmission signal and the vehicle-side transmission signal, the cause of the noise is included in the range including both the vicinity of the portable device 1 and the vicinity of the vehicle. This is effective when there is a disturbing wave or the like.

  In these first to third embodiments, since the portable device transmission signal and the vehicle side transmission signal are transmitted using both of the two transmission / reception channels, communication for setting the transmission / reception channel is performed between the portable device 1 and the vehicle side. There is no need to perform communication with the apparatus 2, and the communication time can be shortened.

  In these embodiments, information on the noise level measured by the portable device 1 is used for transmission control of a signal received by the portable device 1, that is, a vehicle-side transmission signal. In communication between the portable device 1 and the vehicle-side device 2, transmission is possible when the noise level is high only on the transmission side, and the transmission signal itself is unlikely to change due to noise. high. Compared with this, when the noise level is high on the receiving side, the received signal itself is likely to change due to noise and fail to receive, so in these embodiments, the portable device 1 can receive the vehicle-side transmission signal in particular. Probability can be increased.

  Further, in these embodiments, when the noise level is high in the transmission / reception channel 1, signals are transmitted in any transmission / reception channel, and transmission control is changed. The same applies when the noise level is high in the transmission / reception channel 2. Accordingly, for example, when the noise level of the transmission / reception channel 1 is high near the portable device 1 and the noise level of the transmission / reception channel 2 is high near the vehicle, the noise level is different between the portable device 1 side and the vehicle side. Reliable communication can be made possible.

  In these embodiments, signals are transmitted and received through the transmission / reception channel 1 and the transmission / reception channel 2 in which the frequency of the transmission signal of the portable device 1 coincides with the frequency at the time of reception. When the operation unit 11 is operated, the noise levels of the transmission / reception channel 1 and the transmission / reception channel 2 are measured. As a result, not only the reception but also the noise level in the frequency band during transmission is measured. As described above, since the frequency at the time of transmission and the frequency at the time of reception are matched, a circuit can be easily configured by switching between transmission and reception as described above. When the frequency at the time of transmission is different from the frequency at the time of reception, the noise measurement unit 19 may measure the noise level of the reception frequency and include it in the transmission signal.

  In the first to third embodiments, based on the information of the noise level measured by the portable device 1, three transmission controls of increasing the transmission output, decreasing the signal bit rate, and increasing the number of signal transmissions are performed. Each is used alone or in combination. Since these are all effective as means for reducing the influence when the noise level is high, any one or a plurality of means can be applied in a combination different from the above embodiment. Also, other transmission control may be used as long as it is a means for reducing the influence of the noise level.

  Further, it is possible to arbitrarily select whether the information on the noise level measured by the portable device 1 is used for transmission control of the vehicle-side transmission signal, used for transmission control of the portable device transmission signal, or both. Is possible.

  In the second embodiment, the signal transmission order is changed based on the noise level information measured by the portable device 1, the transmission / reception channel having a low noise level is used first, and then the transmission / reception channel is transmitted to another transmission / reception channel. However, the present invention can be applied to the first and third embodiments, and only transmission using a transmission / reception channel with a low noise level may be performed.

  In the first to third embodiments, the noise level information measured by the vehicle-side device 2 is transmitted to the portable device 1 by the vehicle-side transmission signal and is used for displaying on the portable device 1. You may make it use for transmission control of the portable device transmission signal in the portable device 1, and transmission control of the vehicle side transmission signal in the vehicle side apparatus 2. For example, when the portable device 1 receives the vehicle-side transmission signal and then transmits the portable device transmission signal again, and the noise level measured by the vehicle-side device 2 is high, the portable device 1 Transmission control may be performed alone or in combination.

  Moreover, based on the information of the noise level measured in the vehicle side apparatus 2, you may make it limit the transmission / reception channel which can be intermittently received by the vehicle side apparatus 2 to a thing with a low noise level. Further, in the portable device 1, information on the noise level measured by the vehicle-side device 2 is displayed on the display unit 11, but information on the noise level measured by the portable device 1 is also displayed. Also good. The measurement of the noise level in the vehicle side device 2 may be omitted in the first place.

  Next, signal transmission / reception between the portable device 1 and the vehicle-side device 2 in the fourth embodiment will be described. FIG. 6 shows a signal transmission time chart when the operation unit 11 is operated on the portable device 1 when the noise level of the transmission / reception channel 1 is high in the fourth embodiment. In the present embodiment, when the operation unit 11 is operated, the portable device transmission signal is transmitted from the portable device 1 to the vehicle side device 2, but the vehicle side transmission signal is not transmitted from the vehicle side device 2. For this reason, also in the block diagram, a circuit for performing reception in the portable device 1 shown in FIG. 1A and a circuit for performing transmission in the vehicle side device 2 shown in FIG. 1B are omitted. Or control not to work.

  In the present embodiment, it is measured that the noise level of the transmission channel 1 is high in the portable device 1. In this case, the portable device transmission signal transmitted from the portable device 1 is transmitted using only the transmission channel 2 having a low noise level. The vehicle-side device 2 receives the portable device transmission signal from the time step 10 that is the reception timing for the transmission channel 2 while the portable device transmission signal is being transmitted.

  Thus, by changing the transmission control of the portable device transmission signal based on the noise level information measured by the portable device 1, communication can be performed using a transmission channel with a low noise level. In addition, since a transmission channel with a high noise level is not used, the communication time can be shortened. In this case as well, as in the first to third embodiments described above, when it is measured that the noise level is high, transmission is performed by increasing the transmission output, the number of transmissions is increased, or even transmission channel 1 is transmitted. Alternatively, when transmitting on the transmission channel 1, the transmission channel 2 may be transmitted first.

  Although the embodiment of the present invention has been described above, the application of the present invention is not limited to this embodiment, and can be applied in various ways within the scope of its technical idea.

DESCRIPTION OF SYMBOLS 1 Portable device 1a Antenna 1b Portable device transmission / reception part 2 Vehicle side apparatus 2a Antenna 2b Vehicle side transmission / reception part 10 Control part 11 Operation part 12 Display part 13 Oscillator 14 Channel switching circuit 15 Transmission / reception switching device 16 Transmission amplifier 17 Reception amplifier 18 Reception circuit 19 Noise level measurement unit 20 Control unit 21 In-car communication system 22 Other equipment 23 Oscillator 24 Channel switching circuit 25 Transmission / reception switching unit 26 Transmission amplifier 27 Reception amplifier 28 Reception circuit 29 Antenna

Claims (7)

A portable device having a vehicle-side device and a portable device that perform wireless communication with each other, and the portable device transmits a portable device transmission signal to the vehicle-side device and receives a vehicle-side transmission signal from the vehicle-side device. A vehicle-side transmission / reception unit that includes a transmission / reception unit, and the vehicle-side device receives a portable device transmission signal from the portable device and transmits the vehicle-side transmission signal to the portable device when the portable device transmission signal is received. In a keyless entry device having
The portable device includes an operation unit that instructs transmission of the portable device transmission signal, and a noise measurement unit that measures a noise level of a frequency band used for transmitting the vehicle-side transmission signal when the operation unit is operated. And
The vehicle side device acquires information on a noise level measured by the noise measuring unit from the portable device transmission signal, and performs transmission control of the vehicle side transmission signal based on the acquired noise level information. A keyless entry device having a control unit.   The vehicle-side control unit controls the vehicle-side transmission / reception unit to increase the transmission output of the vehicle-side transmission signal when the noise level measured by the noise measurement unit is equal to or higher than a predetermined level. The keyless entry device according to claim 1.   The vehicle-side control unit controls the vehicle-side transmission / reception unit to lower the bit rate of the vehicle-side transmission signal when the noise level measured by the noise measurement unit is a predetermined level or more. The keyless entry device according to claim 1. The portable device transmission / reception unit and the vehicle-side transmission / reception unit have a plurality of transmission / reception channels corresponding to a plurality of frequency bands, and the noise measurement unit measures a noise level of each frequency band corresponding to the plurality of transmission / reception channels. ,
The vehicle side control unit controls the vehicle side transmission / reception unit to preferentially use the transmission / reception channel having the lowest noise level measured by the noise measurement unit. The keyless entry device described. A vehicle-side device and a portable device that perform wireless communication with each other, the portable device includes a portable device transmission unit that transmits a portable device transmission signal to the vehicle-side device, and the vehicle-side device is the portable device In a keyless entry device having a vehicle-side receiving unit for receiving a portable device transmission signal from
The portable device includes an operation unit that instructs transmission of the portable device transmission signal, and a noise measurement unit that measures a noise level of a frequency band used for signal transmission when the operation unit is operated, The keyless entry device, wherein the portable device includes a portable device control unit that performs transmission control of the portable device transmission signal according to a noise level measured by the noise measurement unit.   The portable device control unit controls the portable device transmission unit to increase the number of transmissions of the portable device transmission signal when the noise level measured by the noise measurement unit is a predetermined level or more. The keyless entry device according to claim 5. The portable device transmitter and the vehicle-side receiver have a plurality of transmission channels corresponding to a plurality of frequency bands, and the noise measurement unit measures a noise level of each frequency band corresponding to the plurality of transmission channels. ,
6. The portable device control unit controls the portable device transmission unit to preferentially use a transmission channel having the lowest noise level measured by the noise measurement unit. The keyless entry device described.

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