JPH10227161A - Car radio wave unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multi-functional radio wave unit having a narrow mounting space at a low cost. SOLUTION: An automobile is equipped with an outside car radio wave unit 3 and an inside car radio wave unit. A smart entry function for unlocking a door with verification of ID code and transmitting and receiving antennas 10 and 11 used for proximity sensor for detecting approaching objects to both sides of the automobile are provided to the outside car radio unit 3, and the smart entry function capable of starting an engine with verification of the ID code and transmitting and receiving the antennas used for invasion detecting function for detecting an invader into the inside of the automobile are provided to the inside car radio wave unit. A micro-computer 17 of the outside car radio wave unit 3 switches it function according to car conditions or the presence of person. The micro-computer of the inside car radio wave unit switches its function according to car conditions or the presence of person.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle radio unit mounted on a vehicle and performing various operations by radio waves.

[0002]

2. Description of the Related Art Conventionally, as a vehicle radio wave unit,
Smart entry devices (passive entry devices), proximity sensors (back sonar, etc.), intrusion detection sensors, and the like are used. The following is an explanation of these devices.

[0003] A smart entry device (passive entry device) recognizes a smart card by radio waves transmitted from the vehicle when a driver carries the smart card and approaches the vehicle, and determines an ID code returned from the card. To unlock the door. The antenna of this device is installed inside the door glass or pillar, inside the door mirror, or near the knob of the rear trunk. There is also an indoor unit that recognizes the ID code of the card when a legitimate driver carrying the smart card is seated in the driver's seat and makes the engine startable. The antenna for this device is located near the front panel or center console.

The proximity sensor detects an object in front of, behind, or on the side of the vehicle and issues a warning to the driver or controls the brake system according to the detection result. -A CW radar or the like is used. This sensor is installed in a bumper in front of the vehicle, in an external mirror, or in a rear bumper.

Further, the intrusion detection sensor detects an intruder entering the vehicle interior, and detects the intrusion by a change in a received electric field of a radio wave. In other words, the unmodulated radio wave transmitted from the transmitter changes as the reception electric field of the receiver changes when a person or the like enters the radio wave path, and the detection output of the receiver changes accordingly. By detecting this change, it is possible to detect an intruder entering the vehicle interior. The sensor is installed on the center console in the vehicle interior.

[0006] Each of these devices uses a microwave or the like as a transmission source in order to limit a detection area or a communication area.

[0007]

However, although each of the above systems uses the same radio wave transmission source, the systems are separate and three systems are mounted on a vehicle. In this case, an antenna for a smart entry (for a passive entry) and an antenna for a proximity sensor are mounted outside the vehicle, and an antenna for a smart entry (for a passive entry) and an antenna for an intrusion detection sensor are mounted inside the cabin. Costly,
Mounting space is increased.

Accordingly, an object of the present invention is to provide a low cost,
An object of the present invention is to provide a multi-function vehicle radio unit in which an installation space is reduced.

[0009]

According to the present invention, the function of the operation permission determining means and the function of the proximity state detecting means are switched by the switching means.

The operation permission determining means transmits the radio wave using the transmitting antenna, receives the radio wave transmitted from the portable transceiver in response to the radio wave using the receiving antenna, and receives the radio wave based on the received radio wave. If the ID code matches a previously registered ID code, a predetermined operation is permitted. That is, if the ID codes match, a door unlock operation or the like is performed. Thus, it functions as a smart entry device (passive entry device).

The proximity state detecting means transmits a radio wave using a transmitting antenna, receives a reflected wave of the object with respect to the radio wave using a receiving antenna, and detects a state of the detected object based on the received radio wave. Is detected. That is, it functions as a proximity sensor by issuing a warning when an obstacle approaches the vehicle too much.

That is, the external antenna for smart entry (for passive entry) operates when the driver is not in the vehicle interior, and the proximity sensor operates during traveling, so that both operate simultaneously. Never. Therefore, the transmitting and receiving antenna for the smart entry (passive entry) and the transmitting and receiving antenna for the proximity sensor are shared, and both functions are selectively used by the switching means.
Cost reduction and space reduction are achieved.

According to the second aspect of the present invention, the switching means switches functions according to the state of the vehicle. According to the third aspect of the present invention, the switching means switches to the function of the operation permission determining means when the occupant is detected, and switches to the function of the proximity state detecting means when the occupant is not detected. As described above, the optimization can be performed by performing the function switching in consideration of the presence or absence of the occupant.

According to the present invention, the function of the operation permission determining means and the function of the intrusion detecting means are switched by the switching means. The operation permission determining means receives the radio wave transmitted from the portable transmitter using the receiving antenna, and permits a predetermined operation when the ID code based on the received radio wave matches an ID code registered in advance. That is, if the ID codes match, the vehicle-mounted engine is brought into a startable state, and the like. Thus, it functions as a smart entry device (passive entry device).

The intrusion detecting means transmits radio waves using a transmitting antenna and receives the radio waves using a receiving antenna, and detects an intruder in the vehicle based on the disturbance of the electric field from the received radio waves. Thus, it functions as an intrusion detection sensor.

That is, the in-vehicle antenna for smart entry (for passive entry) operates after the door is unlocked by a legitimate means, and the intrusion detection sensor unlocks the door by a legitimate means. , They do not operate at the same time. Therefore, the transmission / reception antenna for the smart entry (passive entry) and the transmission / reception antenna for the intrusion detection sensor are shared, and both functions are selectively used by the switching means, thereby reducing cost and space.

According to the fifth aspect of the present invention, the switching means switches functions according to the state of the vehicle. According to the invention described in claim 6, the switching means switches to the function of the operation permission determining means when the occupant is detected, and switches to the function of the intrusion detecting means when the occupant is not detected. As described above, the optimization can be performed by performing the function switching in consideration of the presence or absence of the occupant.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a right side view of a passenger car equipped with a vehicle radio unit, and FIG. 2 is a view of the passenger car similarly viewed from behind.

In FIGS. 1 and 2, a vehicle exterior radio unit 3 is mounted inside a door mirror 2 of a vehicle. That is, as shown in FIG. 3, in the door mirror 2, the mirror 4 is attached to the mirror body 5, and the mirror body 5 is rotatably supported by the rotation shaft 6 fixed to the door (vehicle body) 1. ing. A motor housing 7 is formed in the mirror body 5 on the back surface of the mirror 4.
A drive motor, a drive mechanism, and the like are disposed in the power supply. The drive motor includes a motor that stores the door mirror 2, a motor that changes the vertical direction of the mirror 4, and a motor that changes the horizontal direction of the mirror 4. The exterior radio unit 3 is embedded in the surface layer of the mirror body 5.

The external radio unit 3 has a smart entry function and a side proximity sensor function, and determines a response ID code from the card when a driver carrying the smart entry card approaches the vehicle by the smart entry function. Then, the door is unlocked, an object on the side of the vehicle is detected by the proximity sensor function, and a warning is issued to the driver.

As shown in FIG. 4, an in-vehicle radio unit 9 is mounted in a map lamp 8 provided at the center of the ceiling in the passenger compartment. This in-car radio unit 9
Has a smart entry function and an intrusion detection function. The smart entry function enables the engine to be started when a legitimate driver carrying the smart entry card is seated in the driver's seat, and enters the vehicle interior by the intrusion detection function. Intruders are detected.

FIG. 5 shows the electrical configuration of the external radio unit 3. The external radio unit 3 includes a transmitting antenna 10 for transmitting radio waves to the outside of the vehicle, and a receiving antenna 11 for receiving radio waves from the outside of the vehicle. An oscillating unit 12 is connected to the transmitting antenna 10 so that the oscillating unit 12 can transmit a 2.45 GHz radio wave from the antenna 10. The detection unit 14 is connected to the reception antenna 11 via the reception unit 13. The detection unit 14 detects an ID code in the smart entry mode, and detects a delay signal in the proximity sensor mode.

A modulating unit 15 is connected to the oscillating unit 12 so that the modulating unit 15 can modulate a calling code prior to the smart entry mode and transmit the modulated code from the antenna 10, and can generate a pseudo random signal prior to the proximity sensor mode. The signal can be modulated and transmitted from the antenna 10. A delay unit 16 is connected to the oscillation unit 12 and the detection unit 14, and the delay unit 16 operates in the proximity sensor mode.

The external radio unit 3 is provided with a microcomputer 17, which is connected to the oscillating unit 12, the modulating unit 15, and the detecting unit 14, and controls them. In the present embodiment, the microcomputer 17 constitutes unlocking processing means, proximity state detecting means, and switching means.

The microcomputer 17 inputs various signals from the state signal interface circuit 18 indicating the state of the vehicle and the presence or absence of an occupant. More specifically, a door opening / closing signal indicating opening / closing of a door, an engine state signal indicating start / stop of an in-vehicle engine, a lock / unlock signal indicating a door lock state, and an occupant detection signal are input. The door open / close signal is issued from a door open / close switch, and the lock / unlock signal is issued from a door control switch.
The occupant detection signal is issued from a load sensor provided on the seat. Based on these signals, the microcomputer 17 can detect the opening / closing of the door, the engine state, the lock / unlock of the door, and the presence / absence of an occupant.

The microcomputer 17 outputs an unlock command signal and a proximity object detection signal via an output circuit 19.
A body ECU is connected to the output circuit 19 and a body EC is connected to the output circuit 19.
U is connected to a door lock / unlock actuator and an alarm buzzer.

The microcomputer 17 is connected to a power supply 20,
Power is supplied from the power supply 20. FIG. 6 shows an electrical configuration of the smart entry card 21 which is a portable transceiver. The card 21 includes a custom IC 22, a modulator 23, a transmitting / receiving antenna 24, and a power supply 25. The modulator 23 modulates the received radio wave. The custom IC 22 responds when the received electric field level exceeds a certain threshold value and starts a response.

Next, the operation of the thus constructed external radio unit 3 will be described. FIG. 7 shows a flowchart for executing the function switching process by the microcomputer 17.

First, the microcomputer 17 checks the opening / closing of the door in step 101, and if the door is closed, the process proceeds to step 102, where the presence or absence of an occupant is checked in step 102. If there is no occupant, the process proceeds to step 103, At the time of detection, the process proceeds to step 104. The microcomputer 17 determines in step 104
Then, check the start / stop of the engine.
It returns to step 101.

When the engine is started in step 104, the microcomputer 17 proceeds to step 105 and controls the modulation section 15 of FIG. 5 to transmit a pseudo random code signal (radio wave) from the antenna 10. Thereafter, the microcomputer 17 sets the proximity sensor mode in step 106. Thereby, the radio wave unit 3 operates as a proximity sensor.

On the other hand, the microcomputer 17 checks the start / stop of the engine in step 103 when the occupant is not detected, and returns to step 101 when the engine is started. When the engine is stopped, the microcomputer 17 proceeds to step 107 and checks whether the door is locked or unlocked. When locked, the microcomputer 17 proceeds to step 108 to control the modulator 15 in FIG. 5 to transmit a calling code signal (radio wave) from the antenna 10. Thereafter, the microcomputer 17 sets the smart entry mode in step 109. Thereby, the radio wave unit 3 operates as a smart entry device.

In the smart entry mode, a response from the smart entry card 21 in FIG. 6 after transmission of the call code is waited. When the person carrying the smart entry card 21 enters the communication area, the IC 22 of the smart entry card 21 transmits an ID code in response to the radio wave from the radio wave unit 3. The transmitted ID code is transmitted to the receiving unit 1 through the receiving antenna 11 of the radio unit 3.
3 and a reception ID code is sent to the microcomputer 17 via the detection unit 14.

The microcomputer 17 collates the received ID code with a pre-registered ID code, and if the two codes match (if the ID code is correct), the output circuit 1 of FIG.
9 transmits an unlock command signal to the body ECU.
In response to this signal, the body ECU unlocks the door. As a result, the door is unlocked.

Next, the operation in the proximity sensor mode will be described. The pseudo-random signal transmitted in step 105 of FIG. 7 is delayed by the delay unit 16 of FIG. 5, and if the detection target is present near the vehicle, its radio wave is reflected. Received. Then, the microcomputer 17 detects a correlation between the reception signal of the detection unit 14 and the output of the delay unit 16. When the received signal and the delay signal match, the amount of delay by the delay unit 16 indicates the distance between the object reflecting the radio waves and the vehicle. The microcomputer 17 detects whether the reflected signal corresponding to the delay amount is included in the received signal. Then, when the received signal includes the reflection signal of the object, the signal to that effect is output to the output circuit 19. The body ECU emits a warning sound from a warning buzzer to notify the occupant based on the proximity object detection signal. In other words, when the received signal and the output of the delay unit 16 match, the amount of delay indicates the distance to the object reflecting the radio wave. Then, when the vehicle approaches a fence or the like or detects that another vehicle approaches while traveling, a detection signal is output and an alarm buzzer is driven.

Note that the brake system may be controlled at the time of detecting an approaching object. In addition, when the near object is detected, the side-impact airbag is set to the standby state, whereby the malfunction of the airbag can be eliminated.

As described above, the microcomputer 17 determines in step 10
The states of the vehicle (door open / closed state, engine state, door lock /
(Unlock) and switching between the proximity sensor function and the smart entry function depending on the presence or absence of the occupant.

Next, the in-vehicle radio unit 9 will be described. FIG. 8 shows an electrical configuration diagram of the in-vehicle radio unit 9. The in-vehicle radio unit 9 includes a transmission antenna 30 for transmitting radio waves toward the interior of the vehicle, and a reception antenna 31 for receiving radio waves in the interior of the vehicle. An oscillating unit 32 is connected to the transmitting antenna 30, and the oscillating unit 32 outputs 2.45 GHz
The radio wave of z can be transmitted from the antenna 30. The detection unit 3 is connected to the reception antenna 31 via the reception unit 33.
4 are connected. The detection unit 34 detects an ID code in the smart entry mode, and detects a pseudo random signal in the intrusion detection mode.

A modulating unit 35 is connected to the oscillating unit 32. The modulating unit 35 can modulate a call code prior to the smart entry mode and transmit the modulated code from the antenna 30, and generate a pseudo random signal prior to the intrusion detection mode. The signal can be modulated and transmitted from the antenna 30.

The in-vehicle radio unit 9 is provided with a microcomputer 36. The microcomputer 36 is connected to the oscillating unit 32, the modulating unit 35, and the detecting unit 34 and controls them. In this embodiment, the microcomputer 36 constitutes engine start permitting means, intrusion detecting means, and switching means.

The microcomputer 36 inputs various signals indicating the state of the vehicle and the presence or absence of an occupant from the state signal interface circuit 37. Specifically, a door opening / closing signal indicating the opening / closing of the door, a lock / unlock signal indicating the locked state of the door, and an occupant detection signal are input. The door open / close signal is issued from a door open / close switch, the lock / unlock signal is issued from a door control switch, and the occupant detection signal is issued from a load sensor provided on the seat. Based on these signals, the microcomputer 36 can detect opening / closing of the door, locking / unlocking of the door, and presence / absence of an occupant.

The microcomputer 36 outputs an engine start permission signal and an intrusion detection signal via the output circuit 38.
An anti-theft ECU is connected to the output circuit 38, and the anti-theft ECU is connected to an engine control ECU and an alarm buzzer.

The microcomputer 36 is connected to a power supply 39,
Power is supplied from the power supply 39. FIG. 9 shows an electrical configuration of a smart entry card 40 which is a portable transceiver. The card 40 includes a custom IC 41, a modulation unit 42, a transmission / reception antenna 43, and a power supply 44. The modulator 42 modulates the received radio wave. The custom IC 41 responds when the received electric field level exceeds a certain threshold value and starts a response.

Next, the operation of the thus-configured in-vehicle radio unit 9 will be described. FIG. 10 shows a flowchart for executing the function switching process by the microcomputer 36.

First, the microcomputer 36 checks the opening and closing of the door in step 201, and proceeds to step 202 when the door is closed. The microcomputer 36 checks the presence or absence of an occupant in step 202, and when the occupant is detected, the process proceeds to step 203, where the microcomputer 36 transmits the smart entry call code signal (radio wave) to the antenna 30.
To send from. Thereafter, the microcomputer 36 proceeds to step 20.
Step 4 sets the smart entry mode.

On the other hand, when the occupant is not detected in step 202, the microcomputer 36 proceeds to step 205 and checks whether the door is locked or unlocked. When locked, the microcomputer 36 proceeds to step 206 and causes the antenna 30 to transmit a pseudo random code signal (radio wave). Thereafter, the microcomputer 36 sets the intrusion detection mode in step 207.

Next, the operation in the smart entry mode will be described. If the driver carrying the smart entry card 40 is sitting in the driver's seat after transmitting the calling code from the oscillation unit 32 through the transmission antenna 30 in FIG. 8, the IC 41 in FIG. .

The microcomputer 36 of the in-vehicle radio unit 9 receives a radio wave through the receiving antenna 31, compares the received ID code with a previously prepared ID code, and determines that the two codes match each other if they match. Then, the output circuit 38 transmits an engine start permission signal to the anti-theft ECU. The output of the permission signal sets the engine in a startable state. As a result, the engine can be started.

When an incorrect code signal is received or no code signal is received, an engine start prohibition signal is transmitted from the output circuit 38 to the anti-theft ECU. The start of the engine is prohibited by the output of the prohibition signal. As a result, the engine cannot be started.

Next, the operation in the intrusion detection mode will be described. The pseudo random code transmitted in the processing of step 206 in FIG.
3, and the received signal is detected by the detector 34 to obtain an original transmission signal. Here, in the digital modulation, it is well known that there is a certain relationship between the bit error rate of the demodulated digital original signal and the C / N ratio (carrier / noise ratio) of the received radio wave. Naturally, the bit error rate increases as the C / N ratio deteriorates.

The C / N ratio fluctuates due to electric field fluctuation due to the state of the radio wave propagation path. Therefore, the code error rate is almost constant and does not fluctuate in the cabin where there is no intruding object. When there is an intruding object or the like, the C / N ratio deteriorates due to the disturbance of the electric field in the vehicle interior.

When the C / N becomes equal to or more than a certain threshold, the microcomputer 36 detects "intrusion". Then, the microcomputer 36 outputs an intrusion detection signal to the output circuit 38, does not permit the engine to start, and emits an alarm sound from an alarm buzzer.

That is, at the time of intrusion detection, a pseudo-random number is modulated and transmitted, and after reception, demodulation is performed to extract a signal. At this time, the code error rate and the C / N ratio of the received radio wave (carrier / noise ratio) There is a fixed relationship between the error rate and the C / N ratio. The worse the C / N ratio, the higher the bit error rate and the C / N ratio changes due to electric field fluctuation due to the state of the radio wave propagation path. Can be determined to be invaded.

As described above, the microcomputer 17 performs the intrusion detection function and the smart entry based on the vehicle state (door open / closed state, door lock / unlock) and the presence / absence of the occupant in the processing of steps 201, 202, and 205 in FIG. Switch between functions.

As described above, the smart entry system which can carry the smart entry card 21 and unlock the door only by approaching the vehicle, and the external radio unit 3 having the proximity sensor function save more space than the current state. Thus, an unlocking device and a proximity sensor can be realized at low cost. In addition, the in-vehicle radio unit 9 waiting for the intrusion detection function and the smart entry function can provide a high-performance antitheft device at low cost using the smart entry vehicle interior unit.

That is, the vehicle exterior antenna unit 3 having the side proximity sensor function and the door entry smart entry function is installed on the side of the vehicle, and the intrusion detection function and the occupant authentication smart entry are provided on the ceiling in the vehicle compartment. By installing the in-vehicle antenna unit 9 having functions, an intelligent vehicle control device having functions of safety and security can be provided.

In other words, the antenna unit outside the vehicle and the proximity sensor of the smart entry device are integrated, and the antenna unit inside the vehicle and the intrusion detection sensor of the smart entry device are integrated, and the smart entry function and proximity sensor function outside the vehicle and the smart sensor inside the vehicle are integrated. By switching between the entry function and the intrusion detection function according to the state of the vehicle or the like and operating them, the cost and the mounting space are reduced at a lower cost than when four individual radio units having each function are provided.

As described above, this embodiment has the following features. (A) In the external radio unit 3 of FIG. 5, the microcomputer 17 switches between the smart entry function for unlocking the door by collating the ID code and the proximity sensor function for detecting the situation of the detection target, and transmits and receives the same. Antenna 1
By sharing 0 and 11 to use both functions properly, cost reduction and space reduction can be achieved. Also, automatic switching control can be performed by switching functions (modes) depending on the state of the vehicle and the presence or absence of an occupant. (B) In the in-vehicle radio unit 9 shown in FIG. 8, the microcomputer 36 switches between a smart entry function for enabling the engine to be started by collating the ID code and an intrusion detection function for detecting an intruder in the vehicle. In addition, the transmitting and receiving antennas 30 and 31 can be used in common, and both functions can be selectively used, so that the cost can be reduced and the space can be reduced. Also, automatic switching control can be performed by switching functions (modes) depending on the state of the vehicle and the presence or absence of an occupant.

In addition to the embodiments described above,
You may implement as follows. For intrusion detection and proximity detection, a detection method using unmodulated radio waves may be used.
This method can be realized at low cost.

Although the external radio wave unit 3 is buried in the door mirror 2 in the present embodiment shown in FIG. 3, the external radio wave unit on the side of the vehicle may be installed as shown in FIG. As shown by the unit 3 ', it may be a window glass portion (beside the center pillar).

Further, the outside radio wave unit other than the side of the vehicle may be installed in a rear trunk portion of the vehicle as shown by the radio wave outside unit 3 ″ in FIG. When the external radio unit 3 ″ is provided in the rear trunk portion, it has the function of the rear proximity sensor and the smart entry function for opening the trunk.

Further, in the present example shown in FIG. 4, the in-vehicle radio unit is provided in the map lamp 8, but the other in-vehicle radio unit is installed in the in-vehicle radio unit 9 'in FIG. The central panel may be as shown. When installed in such a place (the map lamp 8 or the center panel), directivity can be given to the entire vehicle compartment in the intrusion detection mode.

Further, although the description has been made of the vehicle equipped with both the external radio unit 3 and the internal radio unit 9, only one unit may be mounted on the vehicle. Further, the function (mode) is switched by the microcomputer, but may be switched by a manual switch.

Further, the case where the door or the trunk is unlocked as a smart entry using the antenna outside the vehicle is described, and the case where the start of the engine is permitted as the smart entry using the antenna inside the vehicle has been described. A process for giving permission for a predetermined operation may be performed. Also, a case has been described where a radio wave is transmitted as a smart entry using an in-vehicle antenna and a radio wave transmitted from a card is received in response to the radio wave.
A radio wave transmitted from a card may be received to perform code collation. In other words, at least a receiving function is required.

[Brief description of the drawings]

FIG. 1 is a right side view of a vehicle equipped with a vehicle radio unit according to an embodiment.

FIG. 2 is a view of a vehicle equipped with the vehicle radio unit, also viewed from behind.

FIG. 3 is a sectional view of a door mirror.

FIG. 4 is a diagram showing a vehicle cabin.

FIG. 5 is an electrical configuration diagram of the radio unit for exterior use.

FIG. 6 is an electrical configuration diagram of the smart entry card.

FIG. 7 is a flowchart for explaining the operation of the external radio unit.

FIG. 8 is an electrical configuration diagram of the in-vehicle radio unit.

FIG. 9 is an electrical configuration diagram of the smart entry card.

FIG. 10 is a flowchart for explaining the operation of the in-vehicle radio unit.

[Explanation of symbols]

3 ... Radio unit for exterior, 9 ... Radio unit for interior
0 ... transmitting antenna, 11 ... receiving antenna, 17 ... microcomputer, 30 ... transmitting antenna, 31 ... receiving antenna, 36 ...
Microcomputer

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Mitsuru Otsuka 1-1-1, Showa-cho, Kariya-shi, Aichi Prefecture Inside Denso Corporation (72) Inventor Hiroto Uesaka 1-1-1, Showa-cho, Kariya-shi, Aichi Co., Ltd. Inside DENSO

Claims (6)

[Claims] 1. A transmitting antenna for transmitting a radio wave to the outside of a vehicle, a receiving antenna for receiving a radio wave from the outside of a vehicle, and transmitting a radio wave using the transmitting antenna and responding to the radio wave from a portable transceiver. Operation permission determining means for receiving a transmitted radio wave using the receiving antenna and permitting a predetermined operation when an ID code of the received radio wave matches an ID code registered in advance; A proximity state detecting means for transmitting a signal and receiving a reflected wave from the detection target with respect to the radio wave using the reception antenna, and detecting a state of the detection target based on the received radio wave, and a function of the operation permission determination means. And a switching means for switching the function of the proximity state detecting means. 2. The radio wave unit for a vehicle according to claim 1, wherein the switching means switches functions according to a state of the vehicle. 3. The vehicle according to claim 1, wherein the switching means switches to a function of an operation permission determining means when an occupant is detected, and switches to a function of a proximity state detecting means when no occupant is detected. Radio unit. 4. A transmitting antenna for transmitting a radio wave into a vehicle, a receiving antenna for receiving a radio wave inside the vehicle, and a radio wave transmitted from a portable transmitter is received using the receiving antenna. Operation permission determining means for permitting a predetermined operation when an ID code by radio waves matches an ID code registered in advance; transmitting radio waves using the transmission antenna, receiving the radio waves using the reception antenna, and receiving For a vehicle, comprising: intrusion detection means for detecting an intruder in the vehicle based on the disturbance of the electric field from the transmitted radio wave; and switching means for switching the function of the operation permission determination means and the function of the intrusion detection means. Radio unit. 5. The radio wave unit for a vehicle according to claim 4, wherein the switching means switches functions according to a state of the vehicle. 6. The vehicular radio wave according to claim 4, wherein the switching means switches to a function of an operation permission determining means when an occupant is detected and to a function of an intrusion detecting means when no occupant is detected. unit.