JPH1067285A - Car-mounted load remote control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve directivity of a car-mounted load remote control device by receiving a radio signal transmitted by a portable transmitter at a plural number of points of a vehicle by using a radio type car inside LAN. SOLUTION: A car inside LAN is constituted by mounting a plural number of communication nodes 2 on several positions of the car 3 respectively furnished on an antenna 21. Each of the communication nodes 2 changes receiving frequency from first receiving frequency f1 over to second receiving frequency f2 which is the same as the transmission frequency f2 of a potable transmitter 1 when an ignition switch is in an off operation state. The communication nodes 2, when they receive a radio signal transmitted by the portable transmitter 1, transfer its received content to the other communication nodes 2 and control corresponding car-mounted loads.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved on-vehicle load remote control device for receiving a radio signal transmitted by a portable transmitter on a vehicle side, decoding the radio signal, and controlling a corresponding on-vehicle load. Yes, in particular, the local area network (LOCAL AREANETWORK)
/ Hereafter simply referred to as “in-vehicle LAN”. In-vehicle load remote control that improves the directivity by utilizing the antennas of a plurality of communication nodes that constitute the wireless communication device and receiving the radio signals transmitted by the portable transmitter at a plurality of locations of the vehicle using the antennas. It concerns the device. The present invention is a technique suitable for a so-called keyless entry device or the like that locks and unlocks a door by a radio signal transmitted by a portable transmitter.

[0002]

2. Description of the Related Art As a prior art of this type, for example, a receiving apparatus for remote control of a vehicle load disclosed in Japanese Utility Model Laid-Open Publication No. Hei 6-22108 discloses a radio signal transmitted from a portable transmitter (remote controller). A technique of receiving and converting the control signal into a control signal, transmitting the control signal to each node via a multiplex bus line, and controlling a corresponding vehicle-mounted load has been disclosed.

[0003]

However, when a radio signal transmitted by a portable transmitter is received by an antenna of a vehicle, the directivity of the antenna is important. That is, when a radio wave is received by an antenna of a vehicle, an iron material forming a chassis or the like of the vehicle blocks or reflects the radio wave, and as a result, the directivity of the antenna is complicatedly deformed. On the other hand, the radio signal transmitted from the portable transmitter must use a weak radio wave that conforms to the radio law. Therefore, if the directivity of the antenna is complicatedly deformed as described above, In this case, when a portable transmitter is operated to transmit a radio signal, there is a problem in that the radio signal cannot be received by the receiver on the vehicle side and the in-vehicle load cannot be remotely controlled.

[0004] The present invention is to solve the above-mentioned problem, and receives a radio signal transmitted by a portable transmitter at a plurality of locations in a vehicle, thereby improving the directivity of a vehicle-mounted load. It is intended to provide a device.

[0005]

In order to solve the above-mentioned problems, according to the first aspect of the present invention, a plurality of communication nodes each having an antenna are mounted on various parts of a vehicle and transmitted by a portable transmitter. An on-vehicle load remote control device characterized in that a radio signal is decoded by the plurality of communication nodes and a corresponding on-vehicle load is controlled based on the sum of the decoded signals.

According to a second aspect of the present invention, there is provided an on-vehicle load remote control device, wherein each of the communication nodes includes a receiving circuit for switching a receiving frequency according to an ON / OFF operation state of an ignition switch. provide.

According to a third aspect of the present invention, when the ignition switch is in the OFF operation state, the reception frequency is switched from the first reception frequency to the second reception frequency which is the same as the transmission frequency of the portable transmitter. A vehicle-mounted load remote control device, wherein a circuit is provided in each of the communication nodes.

Further, the invention according to claim 4 provides an on-vehicle load remote control device, wherein an in-vehicle LAN is constituted by the communication nodes.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiment of the present invention exemplifies a so-called keyless entry device which locks and unlocks a door by a radio signal transmitted by a portable transmitter.
Hereinafter, embodiments will be described with reference to the accompanying drawings.

First, a portable transmitter indicated by reference numeral 1 in the drawings will be described. The portable transmitter 1 is a small transmitter carried by the occupant of the vehicle, has the appearance of an ignition key, a key holder or the like, and has a built-in circuit for transmitting a radio signal therein. FIG. 4 exemplifies a circuit built in the portable transmitter 1, which is connected and configured by an antenna 11, an RF amplifier 12, an amplifier 13, a vibrator 14, a coil 15, a variable capacitance diode 16, a CPU 17 and a switch 18. I have.

Next, a communication node indicated by reference numeral 2 in the drawing will be described. The communication node 2 is a unit that is mounted on various parts of the vehicle 3 and forms an in-vehicle LAN, and has a built-in circuit for receiving and transmitting a radio signal. In the embodiment shown in FIG. 1, five communication nodes 2 are mounted on the vehicle, but the number can be increased or decreased according to the purpose. FIG. 3 exemplifies a circuit incorporated in the communication node 2, which is connected and configured by an antenna 21, a receiving circuit 22, a transmitting circuit 23 and a CPU 24. Further, the receiving circuit 22 includes an RF amplifier 221, a mixer 222, an IF
Amplifier 223, detector 224, frequency divider 225, amplifier 2
26, a coil 227, and a variable capacitance diode 228. The transmission circuit 23 includes an RF amplifier 231, a frequency divider 232, an amplifier 233, coils 234, 235, and variable capacitance diodes 236, 237.

The CPU 24 sets the end a to the RF amplifier 231, the end b to the frequency divider 232, and the end c to the coil 2.
The end d is connected to the connection between the variable capacitance diode 236 and the coil 235 with the variable capacitance diode 237.
The end e is connected to the detector 224, the end f is connected to the frequency divider 225, the end g is connected to the connection between the coil 227 and the variable capacitance diode 228, and the ends h and i are door-locked. An end j is connected to an ignition switch 5 and an end k is connected to a DC power supply 6, respectively.

Next, the operation of the above will be described. When the switch 18 is turned on, the portable transmitter 1
Output a predetermined coded signal. This coded signal is supplied to the RF amplifier 12, amplifier 13, oscillator 14,
The signal is modulated by a circuit including the coil 15 and the variable capacitance diode 16 and transmitted from the antenna 11 as a radio wave of the transmission frequency f2.

On the other hand, on the vehicle side, the operation mode of each communication node 2 is changed between when the ignition switch 5 is in the ON operation state and when the ignition switch 5 is in the OFF operation state. For example, when the ignition switch 5 is in the ON operation state, each communication node 2 sets the reception frequency of the reception circuit 22 to the first reception frequency f1, and does not accept a radio signal of the transmission frequency f2 transmitted by the portable transmitter 1. Like
Execute the LAN mode. Also ignition switch 5
Is in the OFF operation state, the reception frequency of the reception circuit 22 of each communication node 2 is switched to the second reception frequency f2 which is the same as the transmission frequency f2 transmitted by the portable transmitter 1, whereby 1 is transmitted to the portable transmitter. The keyless entry mode is executed so as to accept a radio signal to be transmitted.

This will be specifically described with reference to the flowchart shown in FIG. The flowchart is for communication node 2
2 shows a part of the functions programmed in the CPU 24 of FIG.
Mode and keyless entry mode. More specifically, when the communication node 2 determines in step 101 that the ignition switch 5 is in the ON operation state (YES), the communication node 2 proceeds to steps 102 to 103 to execute the LAN mode.

In the LAN mode, first, in step 102,
, The first voltage V1 is output from the end g of the CPU 24, whereby the receiving frequency of the receiving circuit 22 is set to the first receiving frequency f1. At this time, a signal is input to the end f to monitor whether or not the reception frequency is correctly set to the first reception frequency f1, and the end g is set so that the reception frequency always becomes the first reception frequency f1. Adjusts the first voltage V1 output from. Similarly, the transmission circuit 23 monitors the signal at the end b, and sets the transmission frequency to f1 based on the output at the end c. Thus, in step 103, the normal operation of the LAN such as exchanging data between the communication nodes 2 using the radio wave of the frequency f1 is performed.

If it is determined in step 101 that the ignition switch 5 is in the OFF operation state (NO), the process proceeds to steps 104 to 108 to execute the keyless entry mode.

In the keyless entry mode, first, at step 104, the second voltage V2 is output from the end g of the CPU 24, and the receiving frequency of the receiving circuit 22 is set to the second receiving frequency f2. At this time, a signal is input to the end f and the reception frequency is changed to the second reception frequency f2.
Is monitored or not, and the second voltage V2 output from the end g is adjusted so that the reception frequency always becomes the second reception frequency f2. Similarly, the transmission circuit 23 sets the transmission frequency to f2 based on the output of the end c. After executing the step 104, the frequency f2
If it is determined that the signal of (1) has been input (YES), step 10
Proceed to 6.

In step 106, I in the received signal
The D code and the ID code registered in advance in the CPU 24 are collated, and if it is determined that they match (YES), the flow proceeds to step 107.

In step 107, the control code in the received signal is transferred to another communication node 2 through the transmission circuit 23. At this time, the radio wave transmitted by the portable transmitter 1 and
In a case where the radio wave transmitted by the communication node 2 causes a problem due to interference, for example, the radio wave is transmitted from the communication node 2 for a predetermined time after the radio wave from the portable transmitter 1 is stopped. The transmission operation of the communication node 2 may be restricted. After step 107, step 108 is executed.

In step 108, the vehicle-mounted load 4 is controlled according to the control code in the received signal. For example, a door lock actuator which is the vehicle-mounted load 4 is controlled to lock or unlock the door.

As described above, when any one of the communication nodes 2 receives the transmission radio wave from the portable transmitter 1, the control code contained in the radio wave is transferred to the other communication nodes 2 as shown in step 107. , Individual communication nodes 2
Even if the directivity of the communication node 2 is poor as indicated by the symbols A and N in FIG. 2, it is possible to obtain the directivity performance obtained by combining the directivities of the communication nodes 2 as indicated by the symbol P in FIG.

[0023]

According to the present invention, a plurality of communication nodes each having an antenna are mounted on various parts of a vehicle, and a radio signal transmitted by a portable transmitter is decoded by the plurality of communication nodes. Therefore, the directivity of the on-vehicle load remote control device can be improved.

Also, the ON / OF of the ignition switch
Since each of the communication nodes has a receiving circuit that switches a receiving frequency according to the F operation state, it does not receive radio waves from a portable transmitter outside the vehicle while the vehicle is traveling, thereby contributing to safe traveling. .

Further, when the ignition switch is in the OFF operation state, the reception frequency is changed from the first reception frequency to
Since each of the communication nodes includes a receiving circuit that switches to the same second receiving frequency as the transmitting frequency of the portable transmitter,
Radio waves from the portable transmitter can be received only when the vehicle is stopped.

Further, since the in-vehicle LAN is constituted by the communication nodes, the communication node can be used for both the in-vehicle LAN and the keyless entry.

[Brief description of the drawings]

FIG. 1 is a top view of a vehicle according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram illustrating directivity of a communication node illustrated in FIG. 1;

FIG. 3 is an electrical circuit diagram of the communication node shown in FIG. 1;

FIG. 4 is an electric circuit diagram of the portable transmitter shown in FIG. 1;

FIG. 5 is a flowchart illustrating a part of a function programmed in a CPU illustrated in FIG. 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Portable transmitter 2 Communication node 3 Vehicle 4 In-vehicle load 5 Ignition switch 21 Antenna 22 Receiving circuit 23 Transmitting circuit 24 CPU

Claims (4)

[Claims] A plurality of communication nodes (2) each having an antenna (21) are mounted at various places of a vehicle (3),
A radio signal transmitted by the portable transmitter (1) is decoded by the plurality of communication nodes (2), and a corresponding on-vehicle load (4) is controlled based on the sum of the decoded signals. In-vehicle load remote control device. 2. The communication node according to claim 1, wherein each of the communication nodes includes a reception circuit that switches a reception frequency according to an ON / OFF operation state of an ignition switch. An on-vehicle load remote control device characterized by the following. 3. The portable transmitter (1) according to claim 1, wherein the reception frequency is changed from the first reception frequency (f1) when the ignition switch (5) is in an OFF operation state. The on-vehicle load remote control device, wherein each of the communication nodes (2) includes a receiving circuit (22) for switching to a second reception frequency (f2) that is the same as the transmission frequency (f2). 4. The on-vehicle load remote control device according to claim 1, wherein the in-vehicle local area network is constituted by the respective communication nodes (2).