JPH0351787A - Apparatus for measuring space between two objects in close regions - Google Patents

Abstract

PURPOSE: To achieve an inexpensive apparatus with a saving of the expense of a processing path by enabling implementing of the transmission or reception of a light pulse and a high frequency pulse using the same unit. CONSTITUTION: A laser diode 1 is used as optical transmitter. A PIN diode 2 is used as optical receiver. High frequency energy is extracted from the transmitter and radiated via a tape conductor 4 linked to a non-cycle antenna 5 from a transmission pulse generator 3. A directive coupler 6 belongs to the tape conductor 4 to distinguish an input signal from an output signal. When the output of the signal is used in an automobile, the application is performed in a firing circuit 13 as starter for safety system such as assistance system, for instance. In this process, a gas generator is ignited by a widely known method. Thus, the gas generator works to inflate a gas cushion or tension a belt.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] This invention relates to a first object that is a light pulse transmitter, a receiver, and a light pulse that is emitted, reflected by a second object, and then received. The present invention relates to a device for inducing a distance in a close range (less than 100 m) between two objects moving relative to each other, in particular two motor vehicles, having an evaluation circuit following said receiver for measuring distance from time.

[Conventional technology]

A device of this kind is already known from German Patent No. 3,640,449. This known device must also operate as independently as possible from external influences and must be suitable for extracting a useful signal of the received signal that is strongly noise-free.

[Problem of the invention] It is an object of the invention to provide the same or greater reliability when measuring the distance between two objects moving relative to each other, especially two cars in close proximity, and to The goal is to significantly improve or double the cost without incurring any additional costs.

[Means to solve problems]

The above-mentioned problem is solved by the present invention, in which the transmitter (3) does not simply emit light pulses, but rather receives them after being scattered back through the same antenna (2) or through the individual side antennas (5). , directly and/or after amplification or after delay, the same signal processor (11
). In this case, the evaluation circuit is processor-controlled, as described in DE 36 40 449, but evaluation logic or plausibility logic known per se can also be used.

〔Effect of the invention〕

The main advantage of this invention is that it can detect close range anomalies (100
The point is that even if the reliability of distance measurements or distance measurements at m or less) is decisively improved, the device does not become correspondingly more expensive. This situation is achieved in particular by the possibility of transmitting and receiving optical pulses or radio-frequency pulses using the same unit. Via a common path and a measured backscattered signal path, a reliable spacing or distance indication is also possible in detectable proximity, e.g. two transmitters and two receivers and their corresponding separation. There is no cost for processing passages.

The invention thus makes it possible to provide a device for measuring distances in close proximity. In this device, when there is a predetermined distance between two objects moving relative to each other, e.g. two vehicles or a vehicle and an obstacle, an ignition process is performed which reduces this distance and/or triggers an assistance system. For example, the gas cushion is inflated with a known gas generator or the safety belt is tensioned with a belt tensioner. Other measures in response to a collision, such as shutting off the engine, operating the brakes, emitting a warning blinker, warning lamp, warning sound or other warning signal, operating a shock absorber or collision buffer (putting into operation) Such actions can also be initiated.

〔Example〕

Pulse generator for laser diode (half width 1 to 5
0 ns), the high-frequency pulse output is extracted via suitable known devices (eg microconductor technology). For example, from the control current of the laser diode to about 50MH2~
The signal is extracted in a range of about 60 GHz (aperiodically) and radiated via an antenna.

The high-frequency pulse signals reflected from the object to be detected are received by the same antenna and introduced directly and/or after amplification and/or after delay into the same signal processor (°dual gate or corresponding signal processor) for evaluation. do. Therefore, interval measurements are made by comparing or measuring the transit times of high-frequency pulses. In an evaluation logic circuit or a convincing logic circuit, the obtained optical or radio frequency channel spacing measurements are compared and a reliable distance indication or set distance measurement is ascertained.

Only one of the drawings shows a device for measuring the distance between adjacent regions as a specific example. There, a laser diode is used as optical transmitter 1. And P
IN diode 2 is used as an optical receiver.

From this transmitter, high frequency energy is extracted and radiated via a tape conductor 4 leading from a transmitting pulse generator 3 to an aperiodic antenna 5. The tape conductor 4 is associated with a directional coupler 6 in order to distinguish between the input and output signals or through the time flow of the signals. These signals are delayed in an amplification and/or delay line 7 and introduced into a dewar gate circuit 8. The same dewar gate circuit 9 is connected to a sequence control 10, which in turn is connected to the transmit pulse generator 3. Dewar gate circuits 8 and 9 are connected to evaluation logic circuit 11, and dewar gate circuit 8
An optical receiver 2 is connected to this circuit. Output 12 is associated with evaluation logic circuit 11 .

The output of the signal takes place in the ignition stage 13 as a starter for safety systems, such as, for example, support systems when used in a motor vehicle. Here, a gas generator is ignited in a known manner, which inflates the gas cushion or tensions the belt.

Of course, other actions can also be triggered.

This application is not limited to automobiles;

[Brief explanation of drawings]

The attached figure is a block circuit diagram of an apparatus for measuring the distance between adjacent regions. DESCRIPTION OF SYMBOLS 1... Optical transmitter, 2... PIN diode, 3... Transmission pulse generator, 4... Tape conductor, 5... Aperiodic antenna, 6... Directional coupler, 7. ...Delay conductor, 8.9... Dewar gate circuit, 10... Sequence control section, 11... Evaluation logic circuit, 12... Output end, 13... Ignition stage.

Claims (1)

[Claims] 1. A first object is a light pulse transmitter, a receiver, and said receiver measures the distance from the travel time of the light pulses emitted, reflected by the second object, and then received. In devices for promoting distances in close range (less than 100 m) between two objects moving relative to each other, in particular two cars, with a subsequent evaluation circuit, the transmitter (3) only emits light pulses. rather than being received after being scattered back through the same antenna (2) or through individual separate antennas (5), directly and/or after amplification or after a delay, the same signal processor as for the optical signal ( 11) A device characterized in that it is introduced into. 2. In the evaluation logic circuit or satisfaction control logic circuit of the signal or evaluation processor (11), the measurement values (distances) obtained from the optical pulse measurement and the high-frequency pulse measurement are compared, and the quoted part 1
2. Device according to claim 1, characterized in that the output signal is outputted at 2 for driving a display and/or a driver (13). 3. The transmitter has a tape conductor (4) in order to extract the high frequency output radiated non-periodically through the antenna (5) from the pulse generator (3) for the optical pulse transmitter (1). The device according to claim 1 or 2, characterized in that: 4. The antenna (5) is equipped with a
4. Device according to claim 1, characterized in that it is provided with a directional coupler (6). 5. The light pulse and the radio-frequency pulse are introduced together via a single path (7) into a dual gate (8) or an adapted signal processing unit and are evaluated there. The device according to any one of the above.