KR20230103991A - Apparatus and method for optical wireless communication based on fft, m-ary frequency shift keying and full spectrum led - Google Patents

Abstract

An optical signal receiving apparatus according to an embodiment of the present disclosure is electrically connected to a full spectrum camera that generates an image by receiving a full spectrum optical signal transmitted from a full spectrum LED, at least one processor, and the processor, and is performed by the processor. and a memory in which at least one code is stored, and when the memory is executed by a processor, the processor, based on a sensor signal of a camera that captures a light source including a full-spectrum LED, uses an infrared band, a visible band, and an ultraviolet band. An image frame containing all light information of a band is generated, level change information is extracted from an area in which a light source is photographed in the image frame to generate an FSK modulated signal, Fourier transform is performed on the FSK modulated signal, and a frequency is extracted to obtain a plurality of It is divided into bands, and demodulates the FSK modulation signal divided into a plurality of bands using a Mary-Frequency Shift Keying (M-FSK) method based on a preset bit-frequency mapping table and frequency to generate a data stream for each band, Codes causing merging of data streams for each band may be stored.

Description

Optical wireless communication method and apparatus based on full spectrum LED, FFT and M-FSK

The present disclosure relates to an apparatus and method for transmitting signals in optical wireless communication based on full spectrum LEDs and M-ary Frequency Shift Keying (M-FSK).

The contents described below are only described for the purpose of providing background information related to an embodiment of the present invention, and the contents described do not naturally constitute prior art.

Recently, Visible Light Communication (VLC) technology, which is a wireless communication technology in which a communication function is added to visible light wavelengths using an infrastructure in which lights such as incandescent bulbs and fluorescent lights are replaced with semiconductor Light Emitting Diode (LED) lights, has been actively researched.

In addition, an optical camera communication (OCC) technology for demodulating a visible light communication signal received using a camera mounted in a user device such as a general smart phone or a car camera is also being developed.

A camera installed in the user device may photograph the light source using a global shutter method or a rolling shutter method.

Prior Art 1 discloses a technology for communicating by a camera-based M-FSK method based on a camera of a rolling-shutter method, but a general M-FSK method only uses one frequency from one light source at the same time. However, it is difficult to transmit high-speed data.

Prior art 2 discloses a technology for communication by color shift keying (CSK) method, but the general CSK method has a high probability of error according to color recognition dependent on the receiving environment in the receiving device, and a separate technology to recover it There is a problem with this need. In addition, a CSK signal receiving device based on a photo detector has a problem in that it is difficult to recognize a signal due to the influence of ambient light when the distance from the transmitting device increases.

Prior art 1: Korean Patent Registration No. 10-165184 (registered on August 22, 2016) Prior art 2: Korean Patent Registration No. 10-1728518 (registered on April 13, 2017)

An embodiment of the present disclosure provides a device and method capable of transmitting data at high speed in optical wireless communication based on full spectrum LEDs.

Another embodiment of the present disclosure provides a device and method capable of demodulating an M-FSK modulated optical signal transmitted based on a full spectrum LED with an easy configuration.

Another embodiment of the present disclosure provides an apparatus and method capable of stably transmitting data based on Walsh encoding in optical wireless communication based on full spectrum LEDs.

The object of the present invention is not limited to the above-mentioned tasks, and other objects and advantages of the present invention not mentioned above can be understood by the following description and will be more clearly understood by the embodiments of the present invention. It will also be seen that the objects and advantages of the present invention may be realized by means of the instrumentalities and combinations indicated in the claims.

An optical signal receiving method according to an embodiment of the present disclosure is an optical signal receiving method in which a processor of an optical signal receiving apparatus including a rolling shutter-based camera capable of capturing a full spectrum band performs at least a part of each step, Generating an image frame containing all information of infrared band, visible ray band, and ultraviolet band based on a sensor signal of a camera that has photographed a light source including an LED, and obtaining level change information from an area where the light source is photographed in the image frame. Extracting and generating an FSK modulated signal, Fourier transforming the FSK modulated signal, extracting a frequency and dividing the FSK modulated signal into a plurality of bands, and converting the FSK modulated signal divided into a plurality of bands to a preset bit-frequency mapping table and frequency. Based on the method, demodulation using a Mary-Frequency Shift Keying (M-FSK) method to generate data streams for each band, and merging the data streams for each band may be included.

An optical signal receiving apparatus according to an embodiment of the present disclosure is electrically connected to a full spectrum camera that generates an image by receiving a full spectrum optical signal transmitted from a full spectrum LED, at least one processor, and the processor, and is performed by the processor. and a memory in which at least one code is stored, and when the memory is executed by a processor, the processor, based on a sensor signal of a camera that captures a light source including a full-spectrum LED, uses an infrared band, a visible band, and an ultraviolet band. An image frame containing all light information of a band is generated, level change information is extracted from an area in which a light source is photographed in the image frame to generate an FSK modulated signal, Fourier transform is performed on the FSK modulated signal, and a frequency is extracted to obtain a plurality of It is divided into bands, and demodulates the FSK modulation signal divided into a plurality of bands using a Mary-Frequency Shift Keying (M-FSK) method based on a preset bit-frequency mapping table and frequency to generate a data stream for each band, Codes causing merging of data streams for each band may be stored.

A signal transmission apparatus and method according to an embodiment of the present disclosure transmits an M-FSK modulated signal using all bands of infrared band, visible ray band, and ultraviolet band, thereby improving data transmission speed in optical wireless communication. .

A signal transmission apparatus and method according to an embodiment of the present disclosure can demodulate an M-FSK modulated signal transmitted through an optical communication technology in a full spectrum band with an easy configuration.

A signal transmission apparatus and method according to an embodiment of the present disclosure can stably transmit an M-FSK modulated signal in a full spectrum band of optical wireless communication based on a Walsh code.

The effects of the present invention are not limited to those mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description below.

1 is a diagram schematically illustrating communication between a signal transmission device and a signal reception device of full spectrum optical wireless communication according to an embodiment of the present disclosure.
2 is a block diagram showing the configuration of a signal transmission apparatus for full-spectrum optical wireless communication according to an embodiment of the present disclosure.
3 is a diagram illustrating an embodiment of a packet of a data stream according to an embodiment of the present disclosure.
4 is a diagram for explaining a frequency used for M-FSK modulation for full spectrum optical wireless communication according to an embodiment of the present disclosure.
5 is a diagram for explaining a method of generating an optical modulation signal based on an M-FSK modulation signal in full spectrum optical wireless communication according to an embodiment of the present disclosure.
6 is a flowchart illustrating a signal transmission method of full-spectrum optical wireless communication according to an embodiment of the present disclosure.
7 is a block diagram showing the configuration of a signal receiving apparatus for full-spectrum optical wireless communication according to an embodiment of the present disclosure.
8 is a flowchart illustrating a method of demodulating an optical signal received through full-spectrum optical wireless communication according to an embodiment of the present disclosure.
9 and 10 are diagrams for explaining an embodiment of demodulating an optical signal received through full-spectrum optical wireless communication according to an embodiment of the present disclosure.
11 is a block diagram showing the configuration of a signal transmission device for full-spectrum optical wireless communication according to another embodiment of the present disclosure.
12 is a flowchart illustrating a signal transmission method of full-spectrum optical wireless communication according to another embodiment of the present disclosure.
13 is a block diagram showing the configuration of a signal receiving apparatus for full-spectrum optical wireless communication according to another embodiment of the present disclosure.
14 is a flowchart illustrating a signal reception method of full spectrum optical wireless communication according to another embodiment of the present disclosure.
15 is a block diagram showing the configuration of a signal receiving apparatus for full-spectrum optical wireless communication based on Fourier transform according to another embodiment of the present disclosure.
16 is a flowchart illustrating a signal reception method of full-spectrum optical wireless communication based on Fourier transform according to another embodiment of the present disclosure.
17 is a block diagram showing the configuration of a signal receiving apparatus for full-spectrum optical wireless communication based on a band pass filter according to another embodiment of the present disclosure.
18 is a diagram for explaining a method of demodulating a received optical signal of full-spectrum optical wireless communication based on a band pass filter according to another embodiment of the present disclosure.
19 is a flowchart illustrating a signal receiving method of full-spectrum optical wireless communication based on a band pass filter according to another embodiment of the present disclosure.

Hereinafter, the embodiments disclosed in this specification will be described in detail with reference to the accompanying drawings, but the same or similar elements are given the same reference numerals regardless of reference numerals, and redundant description thereof will be omitted. The suffixes "module" and "unit" for components used in the following description are given or used together in consideration of ease of writing the specification, and do not have meanings or roles that are distinct from each other by themselves. In addition, in describing the embodiments disclosed in this specification, if it is determined that a detailed description of a related known technology may obscure the gist of the embodiment disclosed in this specification, the detailed description thereof will be omitted. In addition, the accompanying drawings are only for easy understanding of the embodiments disclosed in this specification, the technical idea disclosed in this specification is not limited by the accompanying drawings, and all changes included in the spirit and technical scope of the present invention , it should be understood to include equivalents or substitutes.

Terms including ordinal numbers, such as first and second, may be used to describe various components, but the components are not limited by the terms. These terms are only used for the purpose of distinguishing one component from another.

It is understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, but other elements may exist in the middle. It should be. On the other hand, when an element is referred to as “directly connected” or “directly connected” to another element, it should be understood that no other element exists in the middle.

Referring to FIG. 1 , communication between a signal transmission device and a signal reception device of optical wireless communication based on full spectrum according to an embodiment of the present disclosure will be described.

Referring to FIG. 1, the signal transmission apparatus 100 receives data and modulates it based on M-FSK, and then transmits the data back to light including all of the infrared (IR) band, the visible light (VL) band, and the ultraviolet (UV) band. It may be configured to transmit the transmission signal modulated into a signal as a full spectrum optical signal through the light source unit 130 including a full spectrum LED supporting all spectrums of the infrared band, the visible ray band, and the infrared band. As the data will be described with reference to FIGS. 2 to 5 , the signal transmission apparatus 100 is a M-ary Frequency Shift Keying (M-FSK) modulation signal for transmitting an optical modulation signal in an infrared band, a visible ray band, and an ultraviolet band. In order to generate each, input data may be separated into a plurality of channels to correspond to a corresponding band, and then modulated in each channel.

In this specification, unless otherwise specified, an optical signal to be transmitted and received is described on the premise that a full-spectrum optical signal including all spectrums of an infrared band, a visible ray band, and an infrared band is assumed.

The signal transmission apparatus 100 divides the data into three channels corresponding to optical modulation signals of infrared band, visible ray band, and ultraviolet band, in order to modulate data by the M-FSK scheme of a plurality of bands, and then separates the data for each channel. Data may be modulated by the M-FSK method.

The signal transmission apparatus 100 may generate an optical modulation signal based on a synthesized signal of a plurality of FSK modulation signals each modulated in three channels. It will be described in detail based on FIG. 5 below.

The signal transmission apparatus 100 may transmit the light modulation signal as an optical signal of the full spectrum band by controlling the light source unit 130 including the full spectrum LED to emit light in the full spectrum band according to the light modulation signal.

The signal receiving device 200 is a strip as shown in FIG. 10 generated based on the sensor signal of the rolling shutter-based camera 210 capable of sensing all of the full spectrum region in which the light source unit 130 including the full spectrum LED is photographed. Data can be generated by generating an FSK modulated signal in the form of a pulse from the (strip) image frame (220), and after the M-FSK decoder 230 extracts a frequency from the FSK modulated signal and demodulates it based on M-FSK .

The camera 210 may be a plurality of cameras including an infrared band camera, a visible ray band camera, and an ultraviolet band camera capable of outputting sensor signals and generating image frames in the infrared band, the visible ray band, and the ultraviolet band, respectively, or an infrared band camera 210 . , a single camera that senses the visible ray band and the ultraviolet band at the same time in the divided sensor area, or a single camera that senses the infrared band, the visible ray band, and the ultraviolet band at different times through filter processing in the same sensor area. It could be a camera.

The signal receiving apparatus 200 may determine a light source area in an image frame based on each sensor signal of an infrared band, a visible light band, and an ultraviolet band, and extract an FSK modulation signal from the image frame of the light source area. The image frame may be a strip-shaped image frame in which light modulation signals of the light source 130 are sensed by respective sensors in the infrared band, the visible ray band, and the ultraviolet band.

The signal receiving apparatus 200 generates an FSK modulated signal based on the strip image frame, and sets the on-level or off-level of parts corresponding to the preamble and the payload, respectively. ) and the shutter speed of the camera, the frequency of the FSK modulation signal can be extracted. The signal receiving apparatus 200 may demodulate the FSK modulated signal in the M-FSK method based on the extracted frequency and a preset bit-frequency mapping table and generate a data stream.

A configuration of a signal transmission device according to an embodiment of the present disclosure will be described with reference to FIG. 2 .

Referring to FIG. 2 , the signal transmission apparatus 100 includes a full spectrum M-FSK encoder, a serial-to-parallel (S2P) converter, a preamble inserter, and a modulator including a full spectrum modulator 113. 110 and a control unit 120 that controls the light source unit 130, which is a communication channel including a full-spectrum LED light source, and may include a clock generator that generates a clock signal.

In one embodiment, the data stream may be a packet obtained by modulating a signal to be transmitted into a binary signal. The modulator may include a Forward Error Correction (FEC) encoder, a preamble inserter, and a binary modulator for modulating input data into a binary signal.

In one embodiment, the full-spectrum M-FSK modulator 110 may modulate a data stream in which a binary signal is configured in a packet form into a full-spectrum data signal. In the following description, it is assumed that the full spectrum M-FSK modulator 110 modulates a binary signal data stream into a full spectrum data signal.

In one embodiment, the full spectrum M-FSK modulator 110 may generate a binary data signal by line coding the binary signal. Line coding may be modulation that outputs input bit 0 as 00 and outputs input bit 1 as 01.

The data stream may be a packet including a payload corresponding to data to be transmitted and a preamble corresponding to a header.

In one embodiment, the signal transmission device 100 may include a sequence number in the packet, the sequence number may be assigned as a continuous number for consecutive data packets, and the sequence number may be a constant number ( bits) can be used repeatedly in order. For example, the sequence number may be 00 for the first packet, 01 for the second packet, and 00 for the third packet. The signal receiving apparatus 200 may determine whether packets are duplicated through the sequence number.

A portion of a packet structure input to the full spectrum M-FSK modulator 110 according to an embodiment of the present disclosure will be described with reference to FIG. 3 . In another embodiment, the full spectrum M-FSK modulator 110 may be configured by converting an input data signal into a part of a packet as shown in FIG. 3 .

The packets obtained by converting the input data signal may include a plurality of data packets (i−1, i, i+1).

Each of the plurality of data packets (i-1, i, i+1) includes a plurality of data sub-packets (eg, data packet (i) includes data sub-packets (i1, i2, i3), Each data subpacket may include a payload composed of information bits corresponding to a portion of the input data.

In one embodiment, in order to prevent packet omission due to a variable frame rate of a receiving camera, a plurality of data subpackets included in one data packet include the same payload composed of the same information bits. can do. That is, the same payload may be repeatedly transmitted to the signal receiving apparatus 200 .

The rolling shutter-based camera of the signal receiving device 200 continuously photographs the flickering of the full-spectrum LED light source multiple times at different times, and stores each photographed signal in one column or row of the image sensor to obtain a strip-shaped image. create a frame In this case, the frame rate of the camera may be variable according to device settings or may be lower than the data packet transmission rate. Therefore, the signal transmission apparatus 100 may configure a data packet to include data subpackets including the same payload in duplicate in order to prevent packet reception loss due to a frame rate limit of a rolling camera. That is, the data subpackets i1, i2, and i3 may include the same payload.

In an embodiment, the signal transmission apparatus 100 may assign a sequence number to each data packet or data subpacket in order to detect packet omission in the signal reception apparatus 200 or to distinguish duplicate packets. And sequence numbers can be assigned as consecutive numbers for consecutive data packets.

In an embodiment, each of the data subpackets i1, i2, and i3 may include the same payload, which is the sequence number of the corresponding data packet i and information bits assigned to the corresponding data packet i.

In one embodiment, the sequence number may be inserted at the front of the packet, or in another embodiment, at both the front and back of the packet. When the sequence number is inserted at both the front and rear ends of the packet, when the signal receiving device 200 finds one preamble in one captured image frame, forward decoding and A packet can be configured by backward decoding.

In one embodiment, the modulated packet or data subpacket may include a header portion including meta information such as packet size in the preamble.

In another embodiment, the preamble is a bit code indicating the start of a packet (Start Frame: SF) and may be a bit code that is previously known to the signal transmission device and the signal reception device.

In another embodiment, the signal transmission apparatus 100 may include a forward error correction (FEC) encoder and an asynchronous bits (Ab) inserter. The preamble may include Ab bits.

The full-spectrum M-FSK modulator 110 of the signal transmission device 100 corresponds to at least a part of a packet in a serial form or a preamble-inserted packet to an optical modulation signal in the infrared band, the visible ray band, and the ultraviolet band. After separating into three channels (PIR, PVL, and PUV), each channel can be modulated by the M-FSK method.

For example, when the bit code of the payload of the packet is '00 01 10', the signal transmission device 100 divides the bit code of the payload '00 01 10' into three channels for each predetermined number of bits, and each ' After separating into 00', '01', and '10', each separated bit code can be modulated by the M-FSK method.

In one embodiment, the preamble may be M-FSK modulated for each channel.

Referring to FIG. 4, a method in which the full spectrum M-FSK modulator 110 according to an embodiment of the present disclosure modulates a bit code input for each channel based on a preset bit frequency mapping table of different frequency bands is described. Explain.

The full spectrum M-FSK modulator 110 may map frequencies based on a table such as Table 1 below to bit codes input for each channel.

IR, VL, and UV in the columns of <Table 1> denote M-FSK modulation channels corresponding to optical modulation signals in the infrared, visible, and ultraviolet bands.

Table 1 shows that two preambles may be mapped to different frequencies in three channels corresponding to optical modulation signals in the infrared, visible, and ultraviolet bands. The following embodiments will be described on the premise that two preambles are mapped to different frequencies in three channels.

Bands of each frequency mapped to the bit codes of the preamble and payload may be as shown in FIG. 4(a).

In one embodiment, the frequencies (f1, f2, f3) mapped to preamble 1 are frequencies of the lowest band (lowest size) in each bit-frequency mapping table of the frequency band allocated to each channel, and The frequencies to be mapped (f1+5delta, f2+5delta, f3+5delta) may be frequencies of the highest band (largest size). In addition, the bit code of the payload is the frequency of the lowest band and the highest band in the bit-frequency mapping table of each channel, that is, the frequencies mapped to preamble 1 (f1, f2, f3, f4; below, the basic frequency ) and the frequencies mapped to the preamble 2 (f1+5delta, f2+5delta, f3+5delta) at equal band intervals. Although FIG. 4 shows four frequencies mapped to the bit codes of the payload for each channel, the mapping to the bit codes of the payload depends on the number of bit codes to be modulated and the frequency bands mapped to preamble 1 and preamble 2. A person skilled in the art can understand that it is possible to change the number of fundamental frequencies. A frequency used for M-FSK modulation in each channel may be understood as an on/off frequency (optical clocking rate) of an infrared band, a visible ray band, and an ultraviolet band of a finally transmitted optical modulation signal.

Frequencies mapped to bitcodes will be described in more detail.

As can be seen in <Table 1>, bitcodes of the preamble and payload are mapped to different frequencies of different bands when they are input to different channels even if they are the same bitcodes. That is, the bit codes input to the channel corresponding to the optical modulation signal in the infrared band are mapped to f1 ~ f1 + 5delta, and the bit codes input to the other channels are also mapped to frequencies (f2 ~ f2 + 5delta) of different frequency bands. It is mapped to frequency (f3 ~ f3 + 5delta). Frequencies of each channel may differ by at least 10 times from frequencies of other channels. This can be applied to all embodiments disclosed in this specification.

That is, even the same bitcode can be mapped to frequencies of different bands, as can be seen in the frequency band of FIG. 4 .

As a result, even when the same bitcode is repeated in the payload (for example, the same bitcode separated from the bitcode '01 01 01' is separately input to three channels and bit frequency mapped), each channel Since the same bit codes input to are each mapped to frequencies of different frequency bands, when the signal receiving apparatus 200 demodulates them, it can check whether the same bit codes are repeated. In addition, when each modulated signal is finally transmitted as an optical modulated signal, there is a very large difference in frequency bands between the infrared band, the visible ray band, and the ultraviolet band, so the possibility of interference is also low. Therefore, even when the signal receiving apparatus 200 demodulates the M-FSK method based on the strip image, there is an advantage in that the packet can be safely demodulated. In addition, since a total of 6 bits can be transmitted at once, there is an effect of improving transmission speed.

In an embodiment, the frequencies of three channels for M-FSK modulation corresponding to light modulation signals in the infrared band, the visible ray band, and the ultraviolet band may differ by 10 times or more from each other for each channel. For example, f2 may be 10 times greater than f1, and f3 may be 10 times greater than f2. Accordingly, the accuracy of the M-FSK demodulation result in different channels of the signal receiving apparatus 200 can be improved.

In an embodiment, the signal transmission apparatus 100 may first transmit an optical signal obtained by converting a preamble when transmitting an optical modulation signal obtained by modulating data.

Accordingly, the signal receiving apparatus 200 demodulates the preamble from the received optical signal and extracts a corresponding frequency, thereby generating bit codes of each payload of packets corresponding to optical modulation signals in the infrared, visible, and ultraviolet bands. A corresponding fundamental frequency band may be determined. For example, the signal receiving apparatus 200 evenly divides the preamble of the infrared band image frame into a previously known number of bands of frequencies (f1, f1+5delta) extracted by demodulating the preamble, and outputs the bit code of each payload. A corresponding frequency band can be determined.

That is, the signal transmission apparatus 100 transmits an optical modulation signal in which an FSK modulation signal to which the frequency of the lowest band and the frequency of the highest band are mapped are modulated for each band, and then the optical modulation signal modulated based on the payload. By transmitting, even if the signal transmitting apparatus 100 changes the frequency band of the bit frequency mapping table and modulates the M-FSK method, the signal receiving apparatus 200 does not separately transmit the table to the bit of the bit frequency mapping table for each band. Each frequency to be mapped to a code can be determined.

After determining the fundamental frequency, the signal receiving apparatus 200 determines the frequency of bit codes for M-FSK modulation corresponding to the light modulation signal of each band at a position separated by a predetermined frequency (Δf, delta) from each fundamental frequency. can be determined by

Referring to FIG. 5 , a method of modulating the FSK modulation signals 510 , 520 , and 530 output for each channel by the full spectrum modulator 113 according to an embodiment of the present disclosure into a full spectrum light modulation signal will be described.

5 illustrates the full spectrum modulator 113 in the case where the M-FSK encoder modulates the M-FSK preamble for each channel.

5 shows that a plurality of FSK modulated signals resulting from bit frequency mapping are synthesized by separately inputting the payload bit code '10 01 00' into three channels of different frequency bands, respectively, to each channel, and synthesizing the infrared band and the visible ray band. and a case of generating an optical modulation signal having both optical characteristics in the ultraviolet band as an example. The shape of the pulse frequency of FIG. 5 is schematically described, and the size of the pulse interval and frequency in the drawing is irrelevant.

The full-spectrum modulator 113 is a parameter (voltage signal) for controlling full-spectrum LEDs suitable for each band based on the frequency of each channel at the same position on the time axis in the FSK modulation signals 510, 520, and 530 modulated in each channel. etc.) can be created.

For example, the optical modulated signal 541 is the frequency f1 and f2 of the FSK modulated signal (may be a signal obtained by modulating the preamble 1) of each channel at the same time position of the FSK modulated signals 510, 520 and 530 for each channel. , It may be a full-spectrum LED that emits light based on the synthesized parameters determined by synthesizing parameters of the infrared band, the visible ray band, and the ultraviolet band corresponding to f3.

Similarly, the optical modulated signal 543 is f1+5delta, f2+5delta, which is the frequency of the FSK modulated signal (which may be a signal obtained by modulating the preamble 2) of the same time position of the FSK modulated signals 510, 520, and 530 for each channel. , is the light modulation signal of the full spectrum LED corresponding to f3 + 5delta, and the light modulation signal 545 is the FSK modulation signal f1 + 3delta, f2 at the same time position of the FSK modulation signals 510, 520 and 530 for each channel. It may be a light modulation signal of a full-spectrum LED corresponding to +2delta or f3+delta.

That is, the signal transmission apparatus 100 determines the parameters of the infrared band, the visible ray band, and the ultraviolet band according to the frequencies of the FSK modulated signals at the same location of the FSK modulated signals 510, 520, and 530 for each channel, and synthesizes them. An optical modulation signal may be generated. Therefore, the light modulation signal finally transmitted through the light source 130 including the full spectrum LED is a light modulation signal having all of the light characteristics of the infrared band, the visible ray band, and the ultraviolet band.

The control unit 120 of the signal transmission device 100 may transmit the light modulation signal as a full spectrum light signal by controlling light emission of the full spectrum LED of the light source unit 130 based on the generated light modulation signal.

In FIG. 5, the full-spectrum LEDs 541, 543, and 545 emit light at each time period as if they were the same in a given time period, but since the frequency of the FSK modulation signal of each channel is different, the full-spectrum LED light emission at each time can be different.

A signal transmission method of a signal transmission apparatus according to an embodiment of the present disclosure will be described with reference to FIG. 6 .

The signal transmission device may receive a packet in the form of a binary signal or receive a transmission signal and convert it into a packet in the form of a binary signal (S110).

The signal transmission apparatus separates at least a portion of the packet by a predetermined number of bits and inputs them to a plurality of channels corresponding to optical modulation signals in the infrared band, the visible ray band, and the ultraviolet band, and the bit codes input for each channel correspond to each channel. An FSK modulation signal for each channel may be generated based on a preset bit frequency mapping table (S120). In this case, the frequencies mapped to the bitcode for each channel may be as shown in Table 1 described above, and the frequencies mapped for each channel may differ by more than 10 times from each other.

The signal transmission device is a parameter (voltage signal, etc.) suitable for each band for controlling full-spectrum LEDs based on the frequency of the FSK modulated signal for each channel at the same position on the time axis in the FSK modulated signal in the form of a pulse wave generated for each channel. It can generate and synthesize it (S130).

The light modulation signal may be an electrical signal or command for controlling the full-spectrum LED to emit light appropriately for each band of desired infrared, visible, and ultraviolet bands, and the signal transmission device generates The full-spectrum LED may be controlled according to the light modulation signal to transmit an optical signal of a full-spectrum band (S140).

A configuration of a signal receiving apparatus 200 based on a full spectrum according to an embodiment of the present disclosure will be described with reference to FIG. 7 .

The signal receiving device 200 includes a rolling camera 210 that generates an image frame based on a signal obtained from an image sensor in a rolling-shutter method for receiving a full-spectrum light signal, and a full-spectrum LED from the image frame. After determining the area to be photographed, a modulation signal generator (not shown) extracts pulse level (ON/OFF) information based on the strip-shaped image of the area to generate an FSK modulation signal, infrared band, visible ray band, and ultraviolet ray band. A multiplier 220 that synthesizes the carrier frequencies of the infrared band, the visible ray band, and the ultraviolet band to the FSK modulated signal of the band, respectively, separates the preamble of the infrared band, the visible ray band, and the ultraviolet band from the FSK modulated signal, and calculates the frequency of the preamble. A full spectrum M-FSK decoder that generates a data stream by demodulating the FSK modulated signal in an M-ary Frequency Shift Keying (M-FSK) method based on the preamble detector 240 and the preamble frequency and bit-frequency mapping table that determine (230).

A signal receiving method of the signal receiving apparatus 200 according to an embodiment of the present disclosure will be described with reference to FIGS. 8 to 10 .

A rolling shutter-based full-spectrum camera (hereinafter referred to as a 'rolling camera') continuously photographs the blinking of a full-spectrum LED light source multiple times at different times, and stores each photographed signal in one column or row of an image sensor. to generate an image frame (S210). The rolling camera sequentially exposes each row or column of the image sensor, so that a signal value corresponding to the light of the LED light source can be obtained according to the blinking of the full-spectrum LED light source in one column or row of the image sensor of the rolling camera. As described with reference to FIG. 1, the rolling camera includes a plurality of infrared band cameras, visible ray band cameras, and ultraviolet band cameras capable of outputting sensor signals and generating image frames in the infrared band, the visible ray band, and the ultraviolet band, respectively. camera, or a single camera that senses the infrared band, the visible ray band, and the ultraviolet band at the same time in each divided sensor area, or the infrared band, the visible ray band, and the ultraviolet band through filter processing in the same sensor area. It may be a single camera sensing in time.

The signal receiving device 200 may generate an infrared band image frame, a visible ray band image frame, and an ultraviolet band image frame in the form of a strip, respectively, as shown in FIG. 10 , based on the signal of the sensor capturing the full spectrum LED (S210). .

The rolling camera continuously captures the blinking of an LED light source multiple times at different times, and stores each captured signal in one column or row of an image sensor to create an image frame. In the rolling camera, by sequentially exposing each row or column of image sensors, a signal value corresponding to the brightness of the LED light source may be obtained according to the flickering of the LED light source in one column or row of the image sensor of the rolling camera. The rolling camera may generate image frames in an infrared band, a visible ray band, and an ultraviolet band, respectively. In the following description, it is assumed that a plurality of cameras including a rolling shutter-based infrared band camera, a visible band camera, and an ultraviolet band camera sequentially expose each row of image sensors to generate a strip-shaped image frame. .

A full-spectrum LED light source includes light components of an infrared band, a visible ray band, and an ultraviolet band, and a plurality of optical signals to be transmitted by a signal transmission device in each band are transmitted as light of a specific frequency of each band. Accordingly, the rolling shutter-based infrared band camera, the visible ray band camera, and the ultraviolet band camera may generate image frames in the infrared band, the visible ray band, and the ultraviolet band, respectively. Each image frame includes different pieces of information modulated by the M-FSK method in a plurality of different channels of the signal transmission device 100 .

The signal receiving apparatus 200 may generate an FSK modulated signal from the strip image frame as shown in FIG. 10 of the area where the full spectrum LED is photographed (S220). The FSK modulation signal may be on or off values extracted from each row or column of the area where the full spectrum LED is imaged. For example, an FSK modulated signal 810 as shown in FIG. 9 may be generated in an image frame of an infrared band.

In one embodiment, the signal receiving apparatus 200 may synthesize the FSK modulated signal of each band by multiplying the synthesized frequencies related to the fundamental frequencies f1, f2, and f3 used by the signal transmitting apparatus 100 for each channel. For example, the FSK modulated signal of the infrared band image frame is multiplied by a signal having a composite frequency of 2xf1 ~ 2 x (f1+5delta), and the FSK modulated signal of the visible light band image frame is 2xf2 ~ 2 x (f2+5delta) A signal having a composite frequency of , and the FSK modulated signal of the UV band image frame may be multiplied by a signal having a composite frequency of 2xf3 to 2x (f3 + 5delta). Since each camera may have some mixed signals of different bands, interference can be reduced by multiplying the synthesized frequency signal.

In an embodiment, the signal receiving apparatus 200 may determine a band of frequencies corresponding to the preamble by separating a signal corresponding to the preamble from the FSK modulated signal, converting the signal into each frequency domain, and extracting a frequency. That is, even if the signal receiving apparatus 200 does not know the basic frequency of each band, it is possible to determine frequencies corresponding to the payload by extracting the bands of frequencies corresponding to the preamble from the FSK modulated signal of each band.

9 is illustratively described as including only a preamble indicating a frequency of each band, and other information such as a sequence number may be additionally included.

The signal receiving apparatus 200 detects a band of frequencies corresponding to each bit code used for demodulation of the payload, and divides the two frequency bands of the preambles of each band equally by a predetermined number of frequencies at positions respectively. It can be determined as frequencies corresponding to bit codes.

The signal receiving apparatus 200 converts the FSK modulated signal 810 to the FSK modulated signal based on the number of pixels corresponding to the shutter speed and the on-level (or may be off-level) of the FSK modulated signal 810. The frequency of 810 can be extracted (S230).

For example, referring to FIG. 10 , strip image frames of infrared band, visible ray band, and ultraviolet band respectively generated by an infrared band camera, a visible ray band camera, and an ultraviolet band camera using a full-spectrum LED light source may be shown in FIG. For each frequency band, the width (number of pixels) of the column (or row) corresponding to ON of the full spectrum LED light source may be different as d1, d2, and d3. The signal receiving apparatus 200 may determine the frequency of the FSK modulation signal in consideration of d1, d2, d3 and the shutter speed of each camera.

The signal receiving apparatus 200 demodulates the FSK modulated signal 810 in an M-ary frequency shift keying (M-FSK) method based on the frequency extracted from the preset bit-frequency mapping table and , and transmits it to another preamble or packet. You can create a data stream by composing a payload. The data stream may be the packets described above.

The full spectrum M-FSK decoder 230 may determine a corresponding bit code by demodulating the FSK modulated signal 810 using the M-FSK method using the table of Table 1 described above. As described above, different frequencies of different frequency bands may be mapped to the same bitcode and transmitted as an optical modulation signal including an infrared band, a visible ray band, and an ultraviolet band. Accordingly, there is an effect of achieving a data transmission rate three times higher than that of a general visible light communication-based optical wireless communication technology.

A configuration of a signal transmission apparatus 100b according to another embodiment of the present disclosure will be described with reference to FIG. 11 . Detailed descriptions of parts overlapping with those previously described will be omitted.

Referring to FIG. 11, the signal transmission apparatus 100b includes a full spectrum M-FSK encoder, a serial to parallel (S2P) converter, a preamble inserter, and a modulator including a full spectrum modulator 113b. 110b and a control unit 120b that controls the light source unit 130b, which is a communication channel including a full-spectrum LED light source, and a clock generator that generates a clock signal.

In one embodiment, unlike the signal transmission apparatus 100 described with reference to FIG. 2, the signal transmission apparatus 100b uses a Walsh coder 111b to generate a Walsh code before the data stream is input to the FSK encoder. The data stream can be encoded (spread) using In this case, a data stream in the form of a packet including a payload and a preamble may be Walsh-encoded.

In one embodiment, the Walsh encoder 111b divides the data stream into a plurality of channels to correspond to channels corresponding to the optical modulation signals of the infrared band, the visible ray band, and the ultraviolet band, and separates Walsh into separate data streams. Codes can be multiplied.

Walsh codes (aka Walsh-Hadamard codes) are a set of orthogonal codes used to separate users on the downlink (DL) channels of CDMA systems, but have never been applied in optical-based wireless communication technologies. This is because the conventional optical-based wireless communication technology can use only one frequency from one light source at the same time, so it is impossible to transmit high-speed data, that is, it is impossible to transmit several bit codes through different channels, so the application of Walsh codes is necessary was not felt by ordinary technicians. In contrast, in an embodiment of the present invention, since high-speed data transmission is possible based on a plurality of bit codes based on frequencies of different bands, robustness of data transmission can be improved by applying a Walsh code.

The code orthogonality between two codes W_i and W_j of Walsh codes is defined as follows.

A plurality of such Walsh codes may be repeatedly generated, and since a method for generating Walsh codes is conventionally known, a detailed description thereof will be omitted.

The signal transmission apparatus 100b converts the Walsh-coded data stream output from the Walsh encoder 111b to frequencies of different bands of channels corresponding to optical modulation signals of infrared band, visible ray band, and ultraviolet band, respectively, in a plurality of channels. FSK modulation signals are generated by modulating each data stream in an M-FSK manner by mapping to bit codes of the data stream.

Referring to FIG. 12, a signal transmission method S100b of the signal transmission apparatus 100b according to another embodiment of the present disclosure will be described. Detailed descriptions of parts overlapping with those described above will be omitted.

The signal transmission apparatus 100b may receive a packet in the form of a binary signal or receive a transmission signal and convert it into a packet in the form of a binary signal (S110b).

The signal transmission apparatus 100b divides at least a portion of the packet-type data stream into a plurality of channels corresponding to optical modulation signals of infrared band, visible ray band, and ultraviolet band, respectively, and transmits the separated data streams for each channel. Each separate Walsh code may be multiplied to generate a Walsh modulated signal (S120b).

The signal transmission apparatus 100b converts the bit codes of the Walsh-modulated signal input for each channel to the infrared band, the visible band, and the visible band based on a preset bit frequency mapping table such as Table 1 corresponding to the infrared band, the visible band, and the ultraviolet band. FSK modulated signals for each channel corresponding to the optical modulated signals of the light band and the ultraviolet band may be generated (S130b).

The signal transmission apparatus 100b is a parameter (voltage) suitable for each band for controlling the full spectrum LED based on the frequency of the FSK modulated signal for each channel at the same position on the time axis in the FSK modulated signal in the form of a pulse wave generated for each channel. Signal, etc.) may be generated and synthesized (S140b).

The light modulation signal may be an electrical signal or command for controlling the full-spectrum LED to emit light appropriately for each band of desired infrared, visible, and ultraviolet bands, and the signal transmission device 100b may transmit an optical signal of a full spectrum band by controlling the full spectrum LED according to the generated optical modulation signal (S150b).

A configuration of a signal receiving apparatus 200b based on a full spectrum according to another embodiment of the present disclosure will be described with reference to FIG. 13 . Detailed descriptions of parts overlapping with those described above will be omitted.

The signal receiving device 200b includes a rolling camera 210b for generating an image frame based on a signal obtained from an image sensor in a rolling shutter method for receiving a full spectrum light signal, and determining an area in which the full spectrum LED is photographed in the image frame. Then, a modulation signal generator (not shown) extracts pulse level (ON/OFF) information based on the strip-shaped image of the corresponding area to generate an FSK modulation signal, and an optical modulation signal in the infrared, visible, and ultraviolet bands. M-FSK decoder that demodulates the FSK modulated signal generated from each channel based on the M-FSK method, Walsh performs Walsh decoding on the data stream (FSK demodulation signal) demodulated from the FSK modulated signal, and generates a final data stream. The decoder 220b separates the preamble for each channel from the FSK modulated signal and the preamble detector 240b determines the frequency of the preamble and demodulates the FSK modulated signal using the M-FSK method based on the frequency of the preamble and a bit-frequency mapping table. and a full spectrum M-FSK decoder to generate a data stream.

The rolling camera 210b of the signal receiving device 200b may include an infrared band filter, a visible ray band filter, and an ultraviolet band filter, and based on the infrared band filter, the visible ray band filter, and the ultraviolet band filter, the infrared image frame is framed. , It is possible to create a visible light band image frame and an ultraviolet band image frame. Based on the infrared band filter, the visible band filter, and the ultraviolet band filter, the infrared image frame, the visible band image frame, and the ultraviolet band image frame are input to the full spectrum M-FSK decoder corresponding to each channel and then demodulated to obtain data. A stream is generated, and the data stream of each channel can be decoded by the Walsh decoding method. The final Walsh-decoded data stream may be concatenated through a parallel to serial (P/S) converter to complete demodulation.

A signal receiving method S200b of the signal receiving apparatus 200b according to another embodiment of the present disclosure will be described with reference to FIG. 14 . Detailed descriptions of parts overlapping with those described above will be omitted.

A full-spectrum camera (hereinafter referred to as a 'rolling camera') including an infrared band-pass filter based on a rolling shutter, a visible-ray band-pass filter, and an ultraviolet band-pass filter (hereinafter referred to as a 'rolling camera') continuously photographs the flickering of a full-spectrum LED light source multiple times at different times, , Each photographed signal is stored in one column or row of the image sensor to generate an image frame (S210b). The image frame may be an infrared band image frame, a visible ray band image frame, and an ultraviolet band image frame in a strip shape as shown in FIG. 10 .

The signal receiving apparatus 200b may generate an FSK modulated signal from the strip image frame shown in FIG. 10 of the area where the full spectrum LEDs are photographed (S220b). The FSK modulation signal may be on or off values extracted from each row or column of the area where the full spectrum LED is imaged. For example, an FSK modulated signal 810 as shown in FIG. 9 may be generated in an image frame of an infrared band.

In an embodiment, the signal receiving apparatus 200b may determine a band of frequencies corresponding to the preamble by separating the signal corresponding to the preamble from the FSK modulated signal and then extracting the frequency.

The signal receiving apparatus 200b extracts the frequency of the FSK modulated signal for each channel based on the number of pixels corresponding to the shutter speed and the on level (or may be off level) of the FSK modulated signal (S230b). , a bit-frequency mapping table such as <Table 1> and a data stream may be generated by demodulating the FSK modulated signal of each band using the M-FSK method, respectively, based on the extracted frequency (S240b).

The signal receiving apparatus 200b may Walsh-decode the M-FSK demodulated data stream to generate a final data stream (S250b).

A configuration of a signal receiving apparatus 200c based on a full spectrum according to another embodiment of the present disclosure will be described with reference to FIG. 15 . Detailed descriptions of parts overlapping with those described above will be omitted. The signal receiving apparatus 200c according to this embodiment may be used corresponding to the signal transmitting apparatus described above with reference to FIG. 2 .

The signal receiving device 200c includes a rolling camera 210c that generates an image frame based on a signal obtained from an image sensor in a rolling shutter method for receiving a full spectrum light signal, and determines an area in which the full spectrum LED is photographed in the image frame. Then, a modulation signal generator (not shown) extracts pulse level (ON/OFF) information based on the strip-shaped image of the corresponding area to generate an FSK modulated signal, Fourier transforms the FSK modulated signal, and extracts a frequency to generate infrared rays. A preamble that determines a frequency mapped to a bit code of each band based on the frequency of the preamble separated by the frequency extractor 220c divided into band, visible ray band, and ultraviolet band, and the frequency extractor 220c of the FSK modulated signal. The detector 240b demodulates the FSK modulated signal in the M-FSK method based on the frequency mapped to the bitcode of each band determined by the frequency and bit-frequency mapping table of the preamble or the preamble detector 240b to generate a data stream It may include a full spectrum M-FSK decoder.

The rolling camera 210c of the signal receiving device 200c may generate an image frame including information of an infrared band, a visible ray band, and an ultraviolet band. Since the image frame includes information of the infrared band, the visible ray band, and the ultraviolet band, the FSK modulated signal generated in the image frame is the optical information of each band and the frequency information of each channel of the optical modulation signal transmitted by the signal transmission device. includes all

Therefore, the frequency extractor 220c of the signal receiving apparatus 200c Fourier transforms the FSK modulated signal including all of the frequency information of each channel into the frequency domain, and then extracts a plurality of frequencies and converts them into the preamble or preamble of each channel. It can be extracted by the frequency of the payload. The extracted frequencies correspond to optical modulation signals in the infrared band, the visible ray band, and the ultraviolet band, respectively.

In an embodiment, the frequency extractor 220c of the signal receiving apparatus 200c extracts the frequency of each preamble of each channel and determines a frequency corresponding to the payload of each band based on the extracted frequency. That is, taking the channel corresponding to the infrared band as an example, the frequency of the lowest band and the frequency of the highest band among the two frequencies extracted from the preamble divided into the channel corresponding to the infrared band are equally divided at a preset interval, A frequency for mapping to the bitcode of the payload may be determined.

A signal receiving method S200c of the signal receiving apparatus 200c according to another embodiment of the present disclosure will be described with reference to FIG. 16 . Detailed descriptions of parts overlapping with those described above will be omitted.

A rolling shutter-based full-spectrum camera (hereinafter referred to as a 'rolling camera') continuously photographs the blinking of a full-spectrum LED light source multiple times at different times, and stores each photographed signal in one column or row of an image sensor. In this way, an image frame including all information of the infrared band, the visible ray band, and the ultraviolet band is generated (S210c). Since the image frame is generated based on a rolling camera, it may be a strip-shaped image frame. Since the rolling camera is full-spectrum based, it can sense all of the infrared band, visible ray band, and ultraviolet band information, so the width of the continuous strip may be different.

The signal receiving device 200c may generate an FSK modulated signal including information of an infrared band, a visible ray band, and an ultraviolet band from the strip image frame of the area where the full spectrum LED is photographed (S220c). The FSK modulation signal may be on or off values extracted from each row or column of the area where the full spectrum LED is imaged.

In an embodiment, the signal receiving apparatus 200c extracts a frequency corresponding to a preamble by Fourier transforming the FSK modulated signal, and then determines a band of frequencies corresponding to the payload of each channel based on the frequency of the preamble.

The signal receiving apparatus 200c performs a Fourier transform on a portion corresponding to the payload of the FSK modulated signal (according to a frequency corresponding to the preamble, an accurate corresponding frequency of the payload portion may be determined) corresponding to the payload of each band. The frequency is extracted (S230c), and based on the bit-frequency mapping table as shown in <Table 1> and the extracted frequency, the FSK modulated signal of each band is demodulated using the M-FSK method to generate a data stream (S240c). ).

A configuration of a signal receiving apparatus 200d based on a full spectrum according to another embodiment of the present disclosure will be described with reference to FIG. 17 . Detailed descriptions of parts overlapping with those described above will be omitted. The signal receiving apparatus 200d according to the present embodiment may be used corresponding to the signal transmitting apparatus described above with reference to FIG. 2 .

The signal receiving device 200d includes a rolling camera 210c generating an image frame based on a signal obtained from an image sensor in a rolling shutter method for receiving a full spectrum light signal, and determining an area in which the full spectrum LED is photographed in the image frame. Then, a modulation signal generation unit (not shown) that generates a modulation signal by extracting pulse level (ON/OFF) information based on the strip-shaped image of the corresponding area, and a device that receives the modulation signal and passes signals of different frequency bands. A filter unit 220d for generating a plurality of FSK modulated signals by inputting them to a plurality of frequency band filter circuits, a preamble detection unit 240d for determining preamble frequencies from the FSK modulated signals divided into respective bands, and a filter unit 220d receives a plurality of FSK modulated signals output from a plurality of band filter circuits of each channel and demodulates the FSK modulated signal in the M-FSK method based on the preamble frequency and bit-frequency mapping table in each channel to generate a data stream It may include a full spectrum M-FSK decoder that

The plurality of band filter circuits of the filter unit 220d receiving the modulated signal apply a band filter corresponding to the frequency of the band related to each channel in the modulated signal including all frequencies of different bands as shown in FIG. A band of FSK modulated signals can be generated.

In the full-spectrum M-FSK decoder, each FSK modulated signal from which the preamble is removed may have different widths (number of pixels) of columns (or rows) corresponding to ON of the full-spectrum LED light source for each band. The signal receiving apparatus 200d may determine the frequency of the FSK modulated signal for each channel by considering the width corresponding to the on level and the shutter speed of the rolling camera 210d. At this time, a frequency for mapping into the bitcode of the payload is further considered by a location obtained by equally dividing the frequency of the lowest band and the frequency of the highest band among the two frequencies extracted from the preamble for each band at a preset interval. can decide

The signal receiving apparatus 200d demodulates the FSK modulated signal of each channel in the M-FSK method based on the frequency extracted from the preset bit-frequency mapping table and , and configures it as a payload of a packet to generate a data stream. there is. The data stream may be the packets described above.

Referring to FIG. 19, a signal receiving method S200d of the signal receiving apparatus 200d according to another embodiment of the present disclosure will be described. Detailed descriptions of parts overlapping with those described above will be omitted.

A rolling shutter-based full-spectrum camera (hereinafter referred to as a 'rolling camera') continuously photographs the blinking of a full-spectrum LED light source multiple times at different times, and stores each photographed signal in one column or row of an image sensor. In this way, an image frame including all information of the infrared band, the visible ray band, and the ultraviolet band is generated (S210d). Since the image frame is generated based on a rolling camera, it may be a strip-shaped image frame.

The signal receiving apparatus 200c may generate a modulated signal including all of the light modulated signal information of the infrared band, the visible ray band, and the ultraviolet band from the strip image frame of the area where the full spectrum LED is photographed (S220d). The modulation signal may be on or off values extracted from each row or column of the area where the full spectrum LED is imaged.

In an embodiment, the signal receiving apparatus 200d may generate a plurality of FSK modulated signals by respectively inputting modulated signals to a plurality of band filter circuits passing signals of different frequency bands (S220d). Subsequently, in an embodiment, the signal receiving apparatus 200d may extract the frequency of the preamble based on the on-level width of the portion corresponding to the preamble in the plurality of FSK modulated signals and the shutter speed of the rolling camera (S230d). . Similarly, the frequency of the payload may be extracted based on the width of the on level of the portion corresponding to the payload in the plurality of FSK modulated signals (S230d).

The signal receiving apparatus 200d demodulates the frequencies of the extracted payloads based on a preset bit-frequency mapping table such as Table 1 using the M-FSK method to generate a data stream, or based on the preamble frequency Based on the frequencies corresponding to the determined payloads of each band, the frequencies of the payloads may be demodulated using the M-FSK method to generate data streams (S240d).

The present disclosure described above can be implemented as computer readable codes in a medium on which a program is recorded. The computer-readable medium includes all types of recording devices in which data that can be read by a computer system is stored. Examples of computer-readable media include Hard Disk Drive (HDD), Solid State Disk (SSD), Silicon Disk Drive (SDD), ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage device, etc. there is Also, the computer may include a processor of each device.

On the other hand, the program may be specially designed and configured for the present disclosure, or may be known and usable to those skilled in the art in the field of computer software. Examples of programs may include not only machine language codes generated by a compiler but also high-level language codes that can be executed by a computer using an interpreter or the like.

In the specification of the present disclosure (particularly in the claims), the use of the term "above" and similar indicating terms may correspond to both singular and plural. In addition, when a range is described in the present disclosure, as including the invention to which individual values belonging to the range are applied (unless otherwise stated), each individual value constituting the range is described in the detailed description of the invention Same as

Unless an order is explicitly stated or stated to the contrary for the steps comprising the method according to the present disclosure, the steps may be performed in any suitable order. The present disclosure is not necessarily limited to the order of description of the steps. The use of all examples or exemplary terms (eg, etc.) in this disclosure is simply to explain the present disclosure in detail, and the scope of the present disclosure is limited due to the examples or exemplary terms unless limited by the claims. it is not going to be In addition, those skilled in the art can appreciate that various modifications, combinations and changes can be made according to design conditions and factors within the scope of the appended claims or equivalents thereof.

Therefore, the spirit of the present disclosure should not be limited to the above-described embodiments, and not only the claims to be described later, but also all ranges equivalent to or equivalent to these claims are within the scope of the spirit of the present disclosure. would be said to belong to

100, 100b, 100c, 100d: signal transmission device
200 ,200b, 200c, 300d: signal receiving device

Claims (8)

An optical signal receiving method in which a processor of an optical signal receiving apparatus including a rolling shutter-based camera capable of capturing a full spectrum band performs at least part of each step,
generating an image frame including light information of an infrared band, a visible ray band, and an ultraviolet band based on a sensor signal of the camera that has captured a light source including a full spectrum LED;
generating an FSK modulation signal by extracting level change information from an area where the light source is photographed in the image frame;
Fourier transforming the FSK modulated signal, extracting a frequency, and dividing the FSK modulated signal into a plurality of bands; and
The FSK modulated signal divided into a plurality of bands is demodulated using a Mary-Frequency Shift Keying (M-FSK) method based on a preset bit-frequency mapping table and the frequency to generate a data stream for each band, and each band merging the data streams separately;
A method for receiving full-spectrum optical signals.
According to claim 1,
Generating the data stream,
Demodulating a frequency of the lowest band and a frequency of the highest band for each band among the frequencies divided into each band into a bit code of a preamble of the data stream,
A method for receiving full-spectrum optical signals.
According to claim 2,
Generating the data stream,
Demodulates frequencies located at equal band intervals between frequency bands corresponding to the preamble into bit codes of the payload of the data stream, and the frequencies mapped to the payload have a difference of 10 times or more from each other for each channel. Further comprising the step of having frequencies,
A method for receiving full-spectrum optical signals.
According to claim 1,
The image frames are demodulated with different bitcodes of the payload of the data stream for each band, respectively.
A method for receiving full-spectrum optical signals.
a full-spectrum camera that generates an image by receiving the full-spectrum light signal transmitted from the full-spectrum LED;
at least one processor; and
A memory electrically connected to the processor and storing at least one code executed by the processor;
When the memory is executed through the processor, the processor,
Based on a sensor signal of the camera that has taken a light source including a full-spectrum LED, an image frame including all light information of an infrared band, a visible ray band, and an ultraviolet band is generated;
Extracting level change information from an area where the light source is photographed in the image frame to generate an FSK modulation signal;
After Fourier transforming the FSK modulated signal, extracting a frequency and dividing it into a plurality of bands;
The FSK modulated signal divided into a plurality of bands is demodulated using a Mary-Frequency Shift Keying (M-FSK) method based on a preset bit-frequency mapping table and the frequency to generate a data stream for each band, and stored with code causing the data streams to be merged;
Full-spectrum optical signal receiving device.
According to claim 5,
The memory causes the processor to:
Further storing a code that causes the frequency of the lowest band and the frequency of the highest band for each band among the frequencies divided into each band to be demodulated into a bit code of a preamble of the data stream,
Full-spectrum optical signal receiving device.
According to claim 6,
The memory causes the processor to:
Further storing a code that causes demodulation of frequencies located at equal band intervals between frequency bands corresponding to the preamble into bit codes of a payload of the data stream;
The frequencies mapped to the payload are frequencies having a difference of 10 times or more from each other for each channel,
Full-spectrum optical signal receiving device.
According to claim 5,
The image frames are demodulated with different bitcodes of the payload of the data stream for each band, respectively.
Full-spectrum optical signal receiving device.

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