JP4945205B2 - Suspicious person monitoring identification method and apparatus - Google Patents

Description

  The present invention relates to a method and apparatus for identifying a suspicious person who does not possess an ID card, which specifies whether a person photographed by a surveillance camera possesses an ID card possessed only by an authorized person.

  Conventionally, in this type of monitoring device, an ID card to which a wireless tag (hereinafter referred to as RFID) or the like is attached is used, but the reach of radio waves emitted from this RFID is narrow. Since presence is detected only around the sensor, even if it is detected, it can be understood that the RFID is in the vicinity of the sensor. If multiple RFIDs are detected, which RFID is the detection target RFID? It was difficult to identify. Therefore, it is easy to identify a suspicious person who does not have an ID card in a situation where a person who has an ID card and a suspicious person who does not have an ID card are mixed. It was difficult to do.

Conventionally, a technique for visualizing the arrival direction of radio waves is known, but a technique for identifying a suspicious person as a subject of the present invention is not disclosed.
JP 2005-24439 A

  Therefore, an object of the present invention is to have an ID card even in a situation where a person who has an ID card at a monitoring target location and a suspicious person who does not have an ID card are mixed. It is an object of the present invention to provide an apparatus and a method for identifying a suspicious person who does not possess an ID card, which can easily identify a suspicious person who does not have an ID card.

The identification method of a suspicious person not possessing an ID card according to the present invention is a method of receiving, demodulating, and AD-converting radio waves from a radio ID card that emits radio waves, digitizing them, and estimating the direction of arrival of received radio waves by radio holography A direction estimating step, an ID demodulating step for receiving the digitized received signal and demodulating the ID information, a photographing step for photographing a monitoring place to obtain image information , receiving the radio wave, and the ID demodulating step If the ID information obtained is the predetermined ID with the the image information obtained by photographing step, the arrival direction arrival direction information of the estimated the received wave obtained in step and before Symbol I D information an image processing step to form a combined and synthesized image, receiving the radio wave, and the ID information obtained by the ID demodulation step is a predetermined ID In this case, the composite image formed in the image processing step is displayed and obtained in the photographing step when the radio wave is not received or the ID information obtained in the ID demodulation step is not a predetermined ID. And an image display step for displaying only an image based on the image information .

The suspicious person monitoring device of the present invention includes a radio ID card that emits radio waves, an array antenna unit that includes a plurality of antenna elements that receive radio waves from the radio ID card, amplifies the received radio waves, and performs AD conversion. A frequency converter that converts the signal to a possible intermediate frequency, an AD converter that converts the received signal received by the array antenna unit and converted to the intermediate frequency into a digital signal by simultaneous sampling, and the digitized reception An arrival direction estimation unit that receives a signal and estimates a direction of arrival of a reception radio wave by the array antenna unit by a radio holography method, an ID demodulation unit that receives the digitized reception signal and demodulates ID information, and a monitoring place a camera unit for photographing a, the ID of the receiving the radio wave array antenna unit, and obtained in the ID demodulator If broadcast is a predetermined ID, an image processing unit for forming a synthesized and the synthesized image to the arrival direction information and prior Symbol I D information of the received radio wave from the arrival direction estimation unit to the photographed image information of the monitoring location And, when the radio wave is received by the array antenna unit and the ID information obtained by the ID demodulating unit is a predetermined ID, the composite image formed by the image processing unit is displayed , An image display unit that displays only an image based on captured image information of the monitoring location when the array antenna unit does not receive the radio wave or the ID information obtained by the ID demodulation unit is not a predetermined ID. It is characterized by this.

  According to the present invention, the radio wave intensity is imaged for each direction of arrival of radio waves from the ID card, and further, the image information is synthesized by superimposing data information such as the surrounding situation of the monitoring place and the position of the person. Since it is displayed on the display unit together with the information, it is possible to easily identify a suspicious person who does not have an ID card and ID information that should not be detected.

  In addition, according to the present invention, the arrival direction of the outgoing radio wave emitted from the ID card is calculated two-dimensionally and the estimated resolution of the arrival direction is improved, so that the radio wave can be obtained even in a place where a plurality of persons are present. The position of the suspicious person can be identified from the direction of arrival of the suspicious person, and it is extremely effective in eliminating the suspicious person.

  Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 1 to 3.

  FIG. 1 is a block diagram showing a configuration of a suspicious person monitoring apparatus according to an embodiment of the present invention. The wireless ID card 1 used in this apparatus is held by a specific person who is permitted to pass to a predetermined place in advance. The wireless ID card 1 is equipped with an active type wireless tag (hereinafter referred to as RFID) that spontaneously emits radio waves. The frequency band of the radio wave used for RFID can be arbitrarily set according to the purpose of use, and the radio wave may be emitted continuously or intermittently, but the emitted radio wave includes the owner's ID information. .

  The radio waves from the wireless ID card 1 are received by the array antenna unit 2 including a plurality of antenna elements 2A to 2B provided in the suspicious person monitoring apparatus main body, and the received radio waves are sent to the frequency conversion unit 3. In the frequency converter 3, the received radio wave is amplified and converted to an intermediate frequency that can be AD converted by a subsequent AD converter (described later).

  The reception signal from the array antenna unit 2 converted by the frequency conversion unit 3 is sent to the AD conversion unit 4, where the reception signals from the plurality of antenna elements 2A to 2B are simultaneously sampled and converted by AD conversion. Digitized.

  This digitized reception signal is sent to the arrival direction estimation unit 5 and the ID demodulation unit 6, and the arrival direction estimation unit 5 estimates the arrival direction of the received radio wave by the array antenna unit 2 by, for example, a radio holography method. It is processed. At this time, the radio wave intensity differs depending on the arrival direction of the radio wave, and therefore, the detected object in the arrival direction with the strongest radio wave intensity is determined as the object of detection.

  On the other hand, in the ID demodulator 6, AD-converted AD data is subjected to digital signal processing, and ID information is demodulated and acquired.

  The arrival direction of the received radio wave and the ID information are sent to the image processing unit 7, and the radio wave intensity of the received radio wave is imaged. The situation is photographed and the output image signal is sent.

  In the image processing unit 7, the arrival direction estimation result obtained by the arrival direction estimation unit 5 and the image taken by the camera unit 8 are superimposed to create a composite image. This composite image is created by measuring the azimuth and elevation angle corresponding to each pixel of the camera image in advance and matching the elevation angle and azimuth angle of the arrival direction estimation result.

  The composite image and the ID information are displayed on the display unit 9 so that the arrival direction of the radio wave emitted from the wireless ID card 1 can be confirmed together with the person in the image. Here, the arrival direction of the radio wave is displayed on the display screen by, for example, dots or cross marks. The ID information is displayed as character information in the vicinity of a mark indicating the direction of arrival of radio waves, for example.

  The array antenna unit 2 is a receiving antenna in which a plurality of antenna elements 2A to 2B are arranged in a grid pattern on a plane and can measure the same frequency band. Also, the shape and type of the antenna, and the antenna The total number and the interval for arranging the antennas can be set arbitrarily according to the measurement object and measurement purpose, and the plane on which the array antenna is arranged in order to suppress the sensation of radio waves incident from the opposite side of the array surface Can also be used as a reflector. In the embodiment described above, although omitted from the drawing, it is needless to say that the same number of receiving systems as antenna elements are required.

  In such a system configuration, a monitoring operation will now be described in a situation where a person who has an ID card and a suspicious person who does not have an ID card are mixed in the monitoring target location. .

  Under such circumstances, the radio wave emitted from the RFID attached to the ID card 1 is received by the array antenna 2 and sent to the frequency converter 3, where the received radio wave is amplified and simultaneously converted to AD. Converted to possible intermediate frequencies. The converted reception signals from the antenna elements 2A to 2B of the array antenna unit 2 are sent to the AD conversion unit 4 and simultaneously sampled, further AD-converted and digitized.

  This digitized data is sent to the arrival direction estimation unit 5 and the ID demodulation unit 6, and the arrival direction estimation unit 5 performs an estimation process of the arrival direction of radio waves by a radio holography method (FIG. 2) described later. At the same time, the ID demodulator 6 demodulates to obtain ID information. These direction-of-arrival direction estimation data and ID information are sent to the image composition processing unit 7, where they are synthesized with the situation around the monitoring location photographed by the camera unit 8, and the synthesized image is displayed on the display unit 9. Is done.

  In this case, when the camera is installed at a position different from the phase center of the array antenna 2, an accurate composite image can be obtained by performing correction using parallax. The image displayed on the display unit 9 also displays the person's ID information, a mark indicating the arrival direction of the radio wave, and the like together with the person image, so that a suspicious person who does not have an ID card can be easily displayed. Can be specified.

  FIG. 2 is a flowchart showing the processing procedure of the direction of arrival estimation process using the radio holography method described above. In step S1, the signal received by the array antenna unit 2 (FIG. 1) is sent to the frequency conversion unit 3 (FIG. 1) and It is converted into digital data through the AD conversion unit 4 (FIG. 1). When the number of antenna elements 2A to 2B (FIG. 1) of the array antenna unit 2 (FIG. 1) is N, N digital data And the digital data per element is M samples.

  In step S2, the digital data obtained in step S1 is fast Fourier transformed (FFT). Using the result of this fast Fourier transform (FFT), the average value of the complex amplitude values is calculated for the frequency range in which the direction of arrival is to be estimated.

  In step S3, a complex amplitude matrix is obtained from the average value of the complex amplitudes obtained in step S2. This complex amplitude matrix is a mathematical matrix in which complex amplitude values are arranged in the same arrangement as the physical arrangement of the antenna elements 2A to 2B (FIG. 1) of the array antenna unit 2 (FIG. 1). is there.

  In step S4, the complex amplitude matrix obtained in step S3 is zero-padded to obtain an extended complex amplitude matrix. This extended complex amplitude matrix is extended to, for example, a 256 × 256 matrix.

  In step S5, a two-dimensional fast Fourier transform (FFT) is performed on the extended complex amplitude matrix obtained in step S4. An arrival direction estimation result can be obtained by performing this two-dimensional fast Fourier transform (FFT). As the arrival direction estimation result, it is possible to obtain the estimated radio wave intensity for each arrival direction, and it is estimated that the radio wave emission source is in the direction in which the estimated radio wave intensity is strong. The arrival direction estimation result is obtained as a matrix, and the rows and columns correspond to the respective angles.

  In the two-dimensional fast Fourier transform (FFT), for example, a one-dimensional fast Fourier transform (FFT) is performed for every row of the extended complex amplitude matrix, and then a one-dimensional fast Fourier transform (FFT) is performed for every column. I do.

  Furthermore, in step S4, the reason why the complex amplitude matrix is an expanded complex amplitude matrix is to intentionally increase the number of samples and improve the arrival direction estimation resolution when performing two-dimensional fast Fourier transform (FFT).

  FIG. 3 is a block diagram showing the system configuration of another embodiment according to the present invention. The difference in configuration from the embodiment shown in FIG. 1 is that between the ID demodulator 6 and the image processor 7. The ID search processing unit 10 and the human detection processing unit 11 are provided between the camera unit 8 and the image processing unit 7, respectively. Therefore, in FIG. 3, the same components as those in FIG. 1 are denoted by the same reference numerals, description of the components and operations of those components will be omitted, and only components and components different from those in FIG. 1 will be mainly described.

  In such a system configuration, the ID search processing unit 10 searches for personal information registered in advance in a database (not shown) or the like based on the ID information acquired by the ID demodulating unit 6, and information corresponding to the ID information. Is sent to the image processing unit 7.

  On the other hand, when the human detection processing unit 11 processes the image acquired by the camera unit 8 and detects a person image, the person detection processing unit 11 detects the position of the person in the image and uses the detected position information as the image processing unit 7. Send to.

  In the image processing unit 7, the detection information detected by the ID search processing unit 10 and the position information of the person detected by the person detection processing unit 11 are superimposed to create a composite image, and the composite image is displayed on the display unit. 9 is displayed.

  At this time, if there is no information corresponding to the ID information as a result of the search by the ID search processing unit 10, or if the ID information is not supposed to be detected, a warning (alarm) is issued to the display unit 9. , Urge supervisors and operators to confirm.

  The human detection processing unit 11 determines whether the detected person has an ID card in consideration of the acquired person detection information, and determines that the detected person does not have an ID card. In the event of a failure, a warning (alarm) is similarly issued to the display unit 9 to prompt the supervisor and operator to confirm.

  4 to 7 are flowcharts for explaining an image processing method in the image processing unit 7 of the suspicious person monitoring apparatus shown in FIG. 1 or FIG. FIG. 4 is a flowchart for explaining an image processing method in the suspicious person monitoring apparatus shown in FIG. The image processing unit 7 shown in FIG. 1 receives the image signal from the camera unit 8 in step S1, and then detects the presence or absence of information from the radio wave arrival direction estimation unit 5 in step S2. When the arrival of a radio wave is detected, ID information included in the radio wave detected in step S3 is detected. When the ID information is detected, radio wave transmission imaging, that is, information from the radio wave arrival direction estimation unit 5 is converted into image information in step S4. The arrival direction information of the radio wave converted into the image information is combined with the camera image information in step S5 and displayed on the display unit 9 in step S6.

  If no information from the direction-of-arrival estimation unit 5 is detected in step S2, or if no ID information is detected in step S3, only the image signal received from the camera unit 8 in step S1 is displayed in step S6. 9 is displayed.

  FIG. 5 is a flowchart for explaining an image processing method in the suspicious person monitoring apparatus shown in FIG. In the figure, processing steps corresponding to those in FIG. 4 are indicated by the same step numbers, detailed description is omitted, and processing steps different from the processing in FIG. 4 will be mainly described. In the flowchart of FIG. 5, after receiving an image signal from the camera unit 8 in step S1, a person image is extracted from the image signal in step S1 ′. After the person image is extracted, radio waves are detected in step 2 in the same manner as in FIG. 4, and then ID is detected and confirmed in step 3 ′. In this step 3 ′, the database registered in the ID search processing unit 10 is searched using the detected ID as a key. If registration information corresponding to the detected ID information exists, the processing step is terminated.

  If radio waves are not detected in step 2, or if it is found that there is no registration information corresponding to the detected ID information or ID information that should not be detected, a warning is issued in step 7 . This warning is displayed as image information on the display unit 9 shown in FIG. 3, or a warning is issued by the display unit 9 or an alarm device (not shown) such as a voice provided separately.

  FIG. 6 is a flowchart for explaining another image processing method in the suspicious person monitoring apparatus shown in FIG. In the figure, processing steps corresponding to those in FIG. 4 or FIG. 5 are indicated by the same step numbers, detailed description is omitted, and processing steps different from those in FIG. 4 or FIG. 5 will be mainly described. In the flowchart of FIG. 6, a person image is extracted from the image signal in step S1 ′, as in the flowchart of FIG. In step 3 ', a database registered in the ID search processing unit 10 is searched using the detected ID as a key. If registration information corresponding to the detected ID information exists, radio wave transmission is performed in step S4. Imaging, that is, information from the arrival direction estimation unit 5 of radio waves is converted into image information. The arrival direction information of the radio wave converted into the image information is combined with the camera image information in step S5 and displayed on the display unit 9 in step S6. Furthermore, when the information from the arrival direction estimation unit 5 is not detected in step S2, or when the ID information is not detected in step S3 ′, or there is no registration information corresponding to the detected ID information, If it is found that the ID information should not be detected, a warning is issued in step 7. This warning is displayed as image information on the display unit 9 shown in FIG. 3, or a warning is issued by the display unit 9 or an alarm device (not shown) such as a voice provided separately.

  FIG. 7 is a flowchart for explaining still another image processing method in the suspicious person monitoring apparatus shown in FIG. In the figure, the same step numbers are displayed for the processing steps corresponding to FIG. 6, detailed description is omitted, and processing steps different from those in FIG. 6 will be mainly described.

  In the flowchart of FIG. 7, when information from the arrival direction estimation unit 5 is not detected in step S2, a warning is issued in step 7, and in step 8, the radio waves of all persons are extracted for the person image extracted in step S1 ′. It is checked whether or not is detected. As a result, if radio waves are detected for some persons, the process proceeds to step 3 '. If radio waves are not detected for all persons, the process proceeds to step S6, and only a camera image is displayed together with an alarm.

  In the flowchart of FIG. 7, in addition, in step 3 ′, a database registered in the ID search processing unit 10 is searched using the detected ID as a key, and registration information corresponding to the detected ID information exists. Proceed to step S4. However, if the ID information is not detected in step 3 ′, or if the registration information corresponding to the detected ID information does not exist, or if it is found that the ID information is not to be detected, In step 9, a warning is issued, and in step 10, the ID information of all members is not detected in the person image extracted in step S <b> 1 ′, registration information corresponding to the detected ID information does not exist, or is detected. It is checked whether or not the ID information should not be set. As a result, if correct ID information is detected for some persons, the process proceeds to step 4. On the other hand, if correct ID information is not detected for all members, the process proceeds to step S6, and only a camera image is displayed together with an alarm.

  In this way, the ID information and the specific information of the person corresponding to the ID information can be confirmed on the display unit 9 together with the radio wave arrival direction and the emission status of the ID information in a state where the person is reflected in the image. Therefore, it is possible to easily identify a suspicious person who does not have an ID card or ID information that should not be detected.

1 is a block diagram schematically showing a system configuration of an embodiment according to the present invention. It is a flowchart which shows the process sequence of the arrival direction estimation process by the radio holography method. It is the block diagram which showed schematically the system configuration | structure of other embodiment by this invention. It is a flowchart for demonstrating the image processing method in the suspicious person monitoring apparatus shown in FIG. It is a flowchart for demonstrating the image processing method in a suspicious person monitoring apparatus shown in FIG. It is a flowchart for demonstrating the other image processing method in the suspicious person monitoring apparatus shown in FIG. It is a flowchart for demonstrating the further another image processing method in the suspicious person monitoring apparatus shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wireless ID card 2 Array antenna part 2A-2B Antenna element
DESCRIPTION OF SYMBOLS 3 Frequency conversion part 4 AD conversion part 5 Arrival direction estimation part 6 ID demodulation part 7 Image processing part 8 Camera part 9 Display part 10 ID search process part 11 Human detection process part

Claims (4)

A radio wave from a wireless ID card that emits radio waves is received, demodulated, AD converted and digitized, and an arrival direction estimating step for estimating an arrival direction of the received radio waves by a radio holography method, and receiving the digitized received signal An ID demodulating step for demodulating the ID information, a photographing step for photographing the monitoring location to obtain image information , and receiving the radio wave and the ID information obtained in the ID demodulating step is a predetermined ID in, the image information obtained in the photographing step, an image processing step of forming a synthesized and the synthesized image to the arrival direction information and prior Symbol I D information of the received radio wave obtained by the arrival direction estimation step, When the radio wave is received and the ID information obtained in the ID demodulation step is a predetermined ID, the image processing step An image that displays a composite image and displays only an image based on the image information obtained in the photographing step when the radio wave is not received or when the ID information obtained in the ID demodulation step is not a predetermined ID. A suspicious person monitoring identification method comprising: a display step.   The suspicious person monitoring and identifying method according to claim 1, wherein the wireless ID card is an active type that spontaneously emits radio waves, and the radio waves to be emitted include ID information. A radio ID card that emits radio waves, an array antenna unit that includes a plurality of antenna elements that receive radio waves from the radio ID card, and a frequency converter that amplifies the received radio waves and converts them to an intermediate frequency that can be AD converted; An AD converter that receives and digitizes a received signal that is received by the array antenna unit and converted to an intermediate frequency, and receives radio waves that are received by the array antenna unit by receiving the digitized received signal Direction estimator for estimating the direction of arrival of radio waves by radio holography, an ID demodulator for demodulating ID information in response to the digitized received signal, a camera unit for photographing a monitoring location, and the array antenna unit And when the ID information obtained by the ID demodulator is a predetermined ID, An image processing unit for forming a composite image by combining the arrival direction information of the received radio wave from the arrival direction estimation unit to the photographed image information of the monitoring location and before Symbol I D information, receive the radio wave at the array antenna unit And when the ID information obtained by the ID demodulating unit is a predetermined ID, the composite image formed by the image processing unit is displayed and the radio wave is not received by the array antenna unit or An suspicious person monitoring apparatus comprising: an image display unit that displays only an image based on captured image information of the monitoring place when the ID information obtained by the ID demodulation unit is not a predetermined ID .   4. The suspicious person monitoring apparatus according to claim 3, wherein the wireless ID card is an active type that spontaneously emits radio waves, and the emitted radio waves include ID information.

Images