KR0159202B1 - Beam detecting apparatus using interrelation of sign - Google Patents

Abstract

The present invention relates to an optical detection device using a correlation of random number codes, which is limited in the detection range of the prior art and practically impossible, and also access / proximity monitoring or taxation of important facilities requiring high security or reliability of a detector. For the purpose of counting the number of objects passing through a detector for the purpose of carrying out such a purpose, an artificial method is used to intentionally place a light emitting device driven by a periodic AC signal having a constant frequency component regardless of the presence or absence of the object. In order to solve the problem that it is difficult to guarantee the normal operation because the operation is possible, the present invention drives the light emitting device by using a random number and the correlator provides a light detector for correlating the random number, so that the distance of light amount by the processing gain of the correlator Effects of attenuation are compensated for by processing gain Can detect a wider range, and I exclude the external operating potential to the sensor by using a signal for detecting a fundamental hayeoteumeuro hydrated to ensure that the number of non-flammable highly.

Description

Optical detection device using correlation of random number code

1A is a block diagram of a conventional optical detection device.

1B is an explanatory diagram of the operation of a conventional photodetector.

Fig. 2A is a block diagram of the optical detection device of the present invention.

FIG. 2B is an internal circuit diagram of the random number generator shown in FIG. 2A.

2C is an explanatory view of the operation of the optical detection device using the correlation of random number code according to the present invention.

* Explanation of symbols for main parts of the drawings

101: AC signal generator 102, 202: light emitting device driver

103, 203: light emitting element 104, 204: object

105, 205: light receiving element 106, 206: preamplifier

107: bandpass filter 108, 208: level detector

201: random number generator 207: correlator

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a photodetector using a correlation of pseudo noise (PN) code. In particular, the present invention relates to a light detecting device that detects the presence or absence of an object by detecting a blockage or reflection by an object between two devices. It relates to a detection device.

In general, as the light detecting device, natural light, a light bulb, a light emitting diode (LED), a laser (LASER), or the like may be used, and a light emitting diode is mainly used.

In addition, a photodetector based on a cadmium sulfide (CdS) -based compound whose conductivity is changed by illuminance, a photo diode, a photo transistor, and the like are mainly used. In this case, a photodiode or a phototransistor having a fast response speed due to the amount of light is used.

As shown in FIG. 1, the conventional optical detector has a light emitting device 103 according to an AC signal generator 101 for generating a periodic AC signal and an AC signal generated by the AC signal generator 101. The light emitting device driver 102 for driving the light emitting device 102, the light receiving device 105 for detecting light when the light emitted from the driven light emitting device 103 is reflected from the target object 104, and the light receiving device 105 A pre-amplifier 106 for amplifying a signal sensed through the pre-, a band-pass filter 107 for filtering only periodic AC signals from the signal amplified by the pre-amplifier 106, and the band-pass filter 107. It consists of a level detector 108 for detecting the presence or absence of the object by comparing the magnitude of the signal filtered by the reference value.

Referring to the operation of the prior art by such a configuration, the light emitting device 103 is driven using a periodic AC signal, and the light emitting device 103 is driven from the signal received by the light receiving device 105. After filtering only the periodic AC signal used in the operation by comparing the magnitude of the signal with a reference value it operates in a manner to detect the presence or absence of the object (104).

In the conventional photodetector as described above, as shown in the operation explanatory diagram of FIG. 1B, the presence or absence of an object is determined only by the received signal intensity of the periodic AC signal, so that the light emitting element 103 is provided on the light receiving element 105 side. Injecting a signal similar to the emitting signal has a vulnerability that does not recognize the presence or absence of an object.

Such a conventional art has a problem in that the configuration is simple, but the detection distance is restricted, and thus it is practically impossible to construct a sensing range of several tens or more even if a light collecting device (lens) is provided on the light emitting device and the light receiving device.

In addition, the number of objects to pass through the detector for the purpose of entry / proximity monitoring or taxation of an important facility where security or detector reliability is highly required, and the relationship between the presence and the presence of the object in the light receiving element in an artificial manner. There is a problem that it is difficult to guarantee the normal operation because it can be intentionally operated, such as by placing a light emitting device driven by a periodic AC signal having only a constant frequency component.

Therefore, an object of the present invention is to provide a reliability and reliability by devising a light sensing function of detecting a correlation value by correlating an PN signal by using an AC signal generator and a correlator in constructing a photo detector to solve the above problems. The present invention provides an optical detection device that uses correlation of random number codes to secure security.

Technical features of the present invention for achieving the above object, a random number code generator for generating a logical random number coder, a light emitting device driver for driving a light emitting device according to the random number code generated from the random number code generator, and the light emitting device driver A light emitting device that emits light to a sensing target area according to driving by the light emitting device, a light receiving device that receives an optical signal that is blocked, reflected, or just passed according to the presence or absence of an object in the sensing target area by light emission of the light emitting device; Correlate by outputting the maximum amplitude when the preamplifier amplifies the observation signal, which is the optical signal received by the device, to a predetermined magnitude, and when the random number coded by the preamplifier and the reference random number code generated by the random number generator coincide with each other. Detect the presence or absence of the object according to the correlator to be processed and the output correlated by the correlator It consists of a level detector that improves the range of detection and improves the performance and the high level of non-flammability of the sensing scheme itself, even when the detector requires a high degree of reliability that can be protected by security control or external manipulation. It is characterized by having security.

In the present invention, instead of using the cyclic AC signal used in the prior art, the change in the correlation value between the random number code used to drive the light emitting device using the random number code and the light emitting device signal is used as a reference value. It is used to compare with.

That is, the present invention extends the detection range in constructing the light detecting device and enables the detector to operate with incombustibility in the sensing method itself even when a high degree of reliability is required that can be protected by security control or external operation. Has improved performance and high security.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

2A illustrates a configuration of an optical detection apparatus according to the present invention. When the configuration is described, a random number code generator 201 for generating a logical random number code and a random number code generated from the random number code generator 201 are described. A light emitting device driver 202 for driving the light emitting device 203, a light emitting device 203 for emitting light to a sensing target area according to the driving of the light emitting device driver 202, and light emission of the light emitting device 203. According to the presence or absence of the object 204 in the sensing region, a light receiving element 205 for receiving an optical signal blocked, reflected or passed through, and an observation signal which is an optical signal received by the light receiving element 205 is predetermined. A phase that is correlated by outputting a maximum amplitude when both the preamplifier 206 amplifying to a magnitude and the random number amplified by the preamplifier 206 and the reference random number code generated from the random number generator 201 coincide. The tube processor 207 and the level detector 208 for detecting the presence or absence of the object 204 according to the output correlated by the correlator 207.

In the above, the circuit of the random number generator has 10 shift registers 201b to 201k connected in series for shifting data and outputting the random number candidate in synchronization with an external clock simultaneously as shown in FIG. 2B. ) And the data output from the third shift register 201d and the random number code data output from the last shift register 201k to perform an exclusive-OR operation to perform an EX-OR operation to input the first shift register 201b. It consists of an exclusive-OR operator 201a input to (D).

Referring to the operation of the present invention by such a configuration as follows.

Referring to FIG. 2B, first, an operation of generating a random number code in the random number generator 201 is as follows.

If the initial state of each shift register is assumed to be '1111111111', the initial state data of each shift register is transferred to the next stage shift register at a positive edge of an externally input clock. Accordingly, the exclusive OR operation 201a performs a logical operation on the data '1' output from the shift register 201k of the last stage and the data '1' output from the third shift register 201d, and the result is obtained. The input is input to the input terminal D of the first shift register 201b. Therefore, the relative of each shift register is '0111111111'. At this time, the output of the shift register 201k of the last stage becomes '1', and if this operation is repeated with a ^2k- 1 sign period (where k is the number of shift registers), a random number code is eventually generated. do.

At this time, the complexity of the random number depends on the random number generation algorithm.

As described above, the random number code generated by the random number generator 201 is a signal suitable for driving the light emitting element 203 and is processed by the light emitting element driver 202 to radiate to the sensing target region through the light emitting element 203. do.

The emitted optical signal is blocked or reflected or just passed according to the presence or absence of the object 204 and observed through the light receiving element 205. The observed signal is amplified to an appropriate signal size through the preamplifier 206. Correlator 207 correlates.

The output of the correlator 207 detects the presence or absence of an object through the level detector 208 and outputs it.

Referring to the overall operation, the signal of the random number generator 201 is driven by the driver 202 to drive the light emitting device 203 and receives the presence or absence of a signal change in the detection range through the light receiving device 205, the preamplifier The level amplified by the correlator 207 is determined by the level detector 208 to detect the presence or absence of the object.

Since the correlator used in the present invention outputs the maximum amplitude only when both input random numbers match, the photodetector configuration prevents the operation of the detector against any external signal having a structure that does not match the internal random number. There is an advantage not to receive.

That is, since the photodetector of the present invention uses the random number code and the correlation characteristic as shown in FIG. 2D, the light detector 205 is in the same state as the random number code used by the apparatus and is in an alarm state unless it is in the same phase. Compared with the prior art photodetector (Fig. 1B), there is an advantage that the damage caused by artificial manipulation can be minimized.

Accordingly, the present invention as described above drives the light emitting device by using a random number code and the correlator provides a photo detector for correlating the random number code so that the influence of attenuation according to the distance of light amount is compensated by the processing gain by the processing gain of the correlator. A wider range can be detected, and the use of a random number-coded detection signal essentially eliminates the possibility of external manipulation in the detector, thus ensuring a high degree of incompatibility.

Claims (1)

Exclusive OR operation based on 10 shift registers connected in series to simultaneously shift external data and output random numbers, data output from the third shift register, and random number data output from the last shift register. A random number generator for generating a logical random number code including an exclusive OR operator inputted to an input terminal of the first shift register and a light emitting device driver for driving a light emitting device according to the random number code generated from the random number generator; And a light receiving device that emits light to a sensing target area according to driving by the light emitting device driving unit, and receives a light signal that is blocked, reflected, or just passed according to the presence or absence of an object in the sensing target area by the light emission of the light emitting device. Element and the light receiving element The correlation is performed by outputting a maximum amplitude when both the preamplifier amplifies the observed signal, which is a received optical signal, to a predetermined magnitude, and when the random number coded by the preamplifier and the reference random number code generated by the random number generator coincide with each other. And a level detector that detects the presence or absence of the object in accordance with the output correlated by the correlator, extending the detection range and requiring a high degree of reliability in which the detector can be protected by security control or external operation. Edo detection system using a random number correlation, characterized in that the improved performance and high security to operate with incompatibility itself.