JPS5912642A - On-car communication system - Google Patents

Abstract

PURPOSE:To realize an inexpensive communication system, by using an ultrasonic wave obstacle detector mounted on a car to detect atn obstacle and performing the communication by means of the ultrasonic wave between the front and the rear cars. CONSTITUTION:When the ultrasonic wave including a frequency F1 for obstacle detection and a frequency F2 modulated at sound information is transmitted from a succeeding car C2 while a distance between cars is measured, an ultrasonic wave receiver 21 receives it, the modulation wave in the frequency F2 is selected at a band-pass filter 23, demodulated and broadcast to a speaker 27. In transmitting the information from the car C1 to the car C2, after a switch 17 is turned on and a switch 28 is turned off, when a microphone 13 receives a speech, the carrier having the frequency F2 of an oscillating circuit 12 is modulated with the sound signal, mixed with the frequency F1 and the result is transmitted from an ultrasonic wave transmitter 16 to the car C2. Thus, the obstacle is detected and the communication between cars is performed at the same time.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an in-vehicle communication system using ultrasonic waves in vehicles such as automobiles, and detects obstacles using an ultrasonic obstacle detection device mounted on the vehicle. The object of the present invention is to provide an in-vehicle communication system that allows communication using ultrasonic waves between front and rear vehicles.

2. Description of the Related Art Conventionally, radio communications such as amateur radio and CD are generally used to communicate between vehicles such as automobiles. However, both require a license and notification, and the devices themselves are expensive and lack privacy. The present invention was invented in view of these circumstances, and by having the configuration described in the claims, it is possible to detect obstacles and at the same time perform mutual communication using ultrasonic waves between the front and rear vehicles. , an inexpensive in-vehicle communication system with excellent privacy.

The present invention will be described below with reference to the drawings.

FIG. 1 shows the configuration of an ultrasonic obstacle detection device used to implement the present invention. This ultrasonic obstacle detection device includes an ultrasonic transmitter 1 and an ultrasonic receiver 2. The ultrasonic transmitting unit 1 is a first ultrasonic wave transmitter that oscillates a pulse having a frequency F1 for detecting an inter-vehicle distance or an obstacle at regular time intervals.
a second oscillation circuit 12 that oscillates a carrier wave with a frequency F2, a modulation circuit 14 that modulates the carrier wave F2 with an audio signal sent from the microphone 13, and a second oscillation circuit 12 that oscillates a carrier wave with a frequency F2;
It is comprised of a mixing circuit 15 that mixes the modulated wave and the F1 frequency pulse, and an ultrasonic transmitter 16 that converts the mixed wave into an ultrasonic wave and sends it out. In addition, the ultrasonic receiving section 2
are an ultrasonic receiver 21 that receives ultrasonic waves, and F
band pass filters 22 and 23 that allow only frequencies F2 to pass; a distance calculation circuit 24 that calculates the distance between vehicles and the distance to an obstacle from the time from transmission of a pulse with frequency F1 to reception of the reflected wave; A display 25 displays the distance traveled to the driver, and a speaker 27 demodulates the modulated wave of frequency F2 obtained by the bandpass filter 23.
It is composed of a demodulation circuit 26 and a signal generator 1, which output the signal as audio. Note that the switch 17 is a breath talk switch, and the switch 28 is a howling prevention switch, and these are configured as interlocking switches.

The ultrasonic obstacle detection device having the above configuration is mounted on each vehicle to which the present invention is applied, for example, vehicles C1 and C2 shown in FIG. 2. That is, the ultrasonic transmitter 16 and the ultrasonic receiver 21 of the ultrasonic obstacle detection device mounted on the vehicle C1 are located in a part of the bumper at the rear of the vehicle and are arranged toward the rear of the vehicle, and Ultrasonic transmitter 16 and ultrasonic receiver 2 of the mounted ultrasonic obstacle detection device
1 is located in a part of the bumper in front of the vehicle and is arranged toward the front of the vehicle. In addition, in order to prevent obstruction detection from interfering with the junior vehicle, one vehicle
For example, the oscillation frequency of the oscillation circuit 11 of the ultrasonic obstacle detection device on the vehicle C2 side is set to Fl, which is different from Fl.

The present invention performs the obstacle detection operation as follows between the vehicles C1 and 02 each equipped with the above-mentioned ultrasonic obstacle detection device, and communicates between the vehicles C1 and C2. It is something to do.

Normally, the vehicle C1, which is the own force, outputs a pulse with a frequency of Fl from the first oscillation circuit 11 at regular time intervals, and the ultra-1'f wave is transmitted through the mixing circuit 15 to the vehicle C2.
It is being sent towards. This ultrasonic wave with a frequency of F hits the vehicle C2 and is then received by the ultrasonic receiver 21 of the vehicle C1 again. Ru.

The distance calculation circuit 24 calculates the distance to the vehicle C from the time from the transmission of the lus to the reception of the reflected pulse at the frequency Fl, and displays the result to the driver on the display 25. A specific display example of the display 25 is shown in FIG. The example in Figure 3 shows the driver by lighting green, red, etc. light-emitting diodes depending on the measured distance between vehicles.If the distance is too close (10cm in this example), a red display will be displayed to warn the driver. Awning.

Now, while measuring the above-mentioned inter-vehicle distance, an audio message with a frequency F1 for detecting an obstacle is heard from the ultrasonic transmitter 16 of the following vehicle C2, as shown by the dotted line in Fig. 1. When the ultrasonic wave containing the frequency F2 modulated by the information is transmitted, the ultrasonic receiver 21 of the vehicle C4 receives it, and the bandpass filter 23 selects the modulated wave of the frequency F2 and sends it to the demodulation circuit. Send to 26th. The demodulation circuit 26 demodulates the received modulated wave to extract an audio signal, and broadcasts the information content from the vehicle C2 to the badge of the vehicle C1 through the audio input 27. At this time, if the distance is such that communication is impossible (due to a lot of noise making it difficult to hear, etc.), the 1 distance calculation circuit 24 switches switch 2.
8 is turned off, and when the callable distance reaches 0, which indicates a warning by displaying yellow on the display 25 (see FIG. 3), the switch 28 is automatically turned on to prepare for reception.

On the other hand, when transmitting information from the vehicle C1, which is the own vehicle, to the vehicle C2, it is sufficient to speak into the microphone 13 after turning on the switch 1γ and turning off the switch 28. As a result, the carrier wave of frequency F2 output from the oscillation circuit 12 is modulated by the audio signal from the microphone 13 in the modulation circuit 14, and sent to the mixing circuit 15 as a modulated wave of frequency F2.

The mixing circuit 15 mixes this modulated wave F2 with the pulse of the frequency F1 sent from the oscillation circuit 11, and then transmits the mixture as an ultrasonic wave from the ultrasonic transmitter 16 toward the vehicle c2.

The following vehicle c2 receives the ultrasonic waves transmitted from the vehicle c1 with its own ultrasonic receiver 21, and passes through the bandpass filter 2.
3, only the modulated wave F2 is selected and sent to the demodulation circuit 26, demodulated into an audio signal, and then broadcast as audio from the speaker 27.

In the above description, the howling prevention switch 28 is provided between the bandpass filter 23 and the demodulation circuit 26, but it is not limited to this position.
The demodulation circuit 261 may be provided in a suspended position with the power to the bandpass filter 23 cut off.

Because of the communication method described above, the present invention has the advantage that it is possible to detect an obstacle and at the same time communicate between vehicles using the ultrasonic obstacle detection device mounted on the vehicle.

Furthermore, since ultrasonic waves are directional, they are highly confidential, and communication is carried out by borrowing some of the functions of ultrasonic obstacle devices installed in vehicles, providing an inexpensive communication system. It has a remarkable effect.

[Brief explanation of drawings]

Figure 1 is a block diagram of the ultra-rgo pseudo-βV detection system used in the present invention, Figure 2 is an explanatory diagram of the in-vehicle communication system of the present invention, and Figure 3 is ultrasonic/wave obstacle detection. FIG. 3 is a diagram showing an example of a display on a display of the device. 1: Ultrasonic transmitter, 2: Ultrasonic receiver, 11: First oscillation circuit, 12: Second oscillation circuit, 13: Microphone, 14:
Modulation circuit, 15: Mixing circuit 116: Ultrasonic transmitter, 21
: Ultrasonic receiver, 22.23: Bandpass filter, 2
4: distance calculation circuit, 25: display, 26: demodulation circuit, 2
7: Speaker, 01 * C2: Vehicle, Fl: Frequency of ultrasonic pulse for obstacle detection, F2: Frequency of ultrasonic wave for communication. Patent applicant Toyota Motor Corporation Agent Rikichi Ichiyo (1 other person)

Claims (1)

[Claims] Between vehicles each equipped with an ultrasonic obstacle detection device, the ultrasonic pulse for obstacle detection transmitted from the ultrasonic obstacle detection device of one vehicle toward the other vehicle has a frequency of the ultrasonic pulse. A communication ultrasonic wave having a different frequency and modulated by the audio signal to be transmitted is superimposed and transmitted, and the ultrasonic wave consisting of these two components is transmitted by the ultrasonic obstacle detection device of the other vehicle. An on-vehicle communication system characterized in that the ultrasonic waves for communication are received, selectively separated from the received ultrasonic waves, demodulated, and converted into audio.