WO2023039827A1 - Optimization method based on fusion of visible light communication and visible light positioning - Google Patents

Abstract

Disclosed in the present invention is an optimization method based on fusion of visible light communication and visible light positioning. The method comprises: a terminal device decoding received modulation information of visible light communication, determining identifiers of visible light units, calculating the received optical power of a plurality of visible light units, and thereby determining position information by means of trilateration; the terminal device embedding the position information into a media access layer protocol, and sending same to a central controller; and by taking the optimization of the communication performance between the terminal device and the visible light units as a target, the central controller controlling and adjusting the radiation distribution of the related visible light units according to the received position information, and feeding back an adjustment result to the terminal device by means of the media access layer protocol. By means of the present invention, automatic adaptation to a change of the position of a user can be realized, thereby optimizing visible light communication and positioning.

Description

An optimization method based on fusion of visible light communication and visible light positioning technical field

The invention relates to the field of communication technology, in particular to an optimization method based on fusion of visible light communication and visible light positioning.

Background technique

With the emergence of bandwidth-intensive applications such as augmented reality (AR), virtual reality (VR), mobile streaming, mobile 4K video, etc., the demand on wireless communication resources is growing at an unprecedented rate. As data demands grow, the low-frequency electromagnetic spectrum used for wireless communications becomes increasingly crowded. Extensive research has attempted to alleviate resource shortages by exploiting neglected parts of the hyperspectrum, such as millimeter-wave bands and visible-light bands. Among them, visible light communication, as a supplementary method of radio frequency communication, has attracted extensive attention because it can utilize light-emitting diodes (LED lights) for lighting infrastructure, can be deployed in large quantities, and can be highly scalable in frequency.

Visible light communication broadcasts information on optical channels to realize communication between terminal equipment and LED lights. Visible light communication was born to solve the problem of scarce frequency resources. The latest research shows that a one-way communication data rate of 1.35Gbps can be achieved using a single 1W commercial phosphorescent white LED lamp. In addition, visible light communication is not only rich in spectrum resources, but also requires no authorization, and has the characteristics of high confidentiality, which has attracted extensive attention from academia and industry. With the development of visible light communication technology, since a single LED lamp satisfies the Lambert (Lambert) radiation model, the distance to the radiator can be estimated by calculating its optical power, so that visible light can be used for indoor positioning as a variety of positioning methods supplement.

However, VLC also has some disadvantages. For example, it can only work in optical line-of-sight, because the optical power received from non-line-of-sight links is usually much smaller and ignored. Although visible light can provide high-quality downlink communication services, due to hardware limitations, it is not practical to place visible light communication transmitting units on terminal devices, which also brings difficulties in information uploading. A practical solution is to integrate visible light communication and wireless local area network (mainly based on WiFi). As an emerging high-speed wireless communication technology, visible light has been established in the Institute of Electrical and Electronics ) Standardized in 802.15.7. In the hybrid network, when the optical line-of-sight of the user equipment is available, the wireless LAN channel is used for data upload, and the visible light communication channel and the wireless LAN channel are used for the downlink at the same time as the auxiliary control frame transmission or when the optical link is not available. below as a supplement.

Disadvantages of visible light communication In addition to line-of-sight transmission, in the visible light downlink, due to the inherent characteristics of Lambertian radiators, the communication quality varies greatly in different locations. For a specific user, the source of VLC fluctuations is the change in the angle of incidence and the angle of radiation. Changing the orientation of the user equipment (such as a photodiode) so that it is aligned with the visible light unit can reduce the size of the incident angle, thereby improving the overall visible light communication quality. However, in practical applications, the user-activated adjustment method needs to be actively performed by the user, which is difficult to meet actual needs.

Contents of the invention

The purpose of the present invention is to overcome the defects of the above-mentioned prior art, and provide an optimization method based on fusion of visible light communication and visible light positioning, which includes:

Step S10: The terminal device decodes the received modulation information of visible light communication, determines the identity of the visible light unit and calculates the optical power of the received multiple visible light units, and then determines the location information by using the trilateration method;

Step S20: the terminal device embeds the location information in the media access layer protocol and sends it to the central controller;

Step S30: Aiming at optimizing the communication performance between the terminal device and the visible light unit, the central controller controls and adjusts the radiation distribution of the relevant visible light unit according to the received position information, and feeds back the adjustment result to the terminal device via the media access layer protocol.

Compared with the prior art, the present invention has the advantage that under indoor LED lighting, visible light communication and visible light positioning services are provided to end users such as smartphones at the same time, and the present invention can be realized by using existing lighting equipment. Moreover, the rotation of the visible light unit can provide a larger positioning range and achieve a higher communication rate without changing the lighting facility, thereby automatically adapting to changes in the user's position and optimizing visible light communication and positioning. The realization method of the present invention is efficient, integrates communication and positioning, and can enhance each other.

Other features of the present invention and advantages thereof will become apparent from the following detailed description of exemplary embodiments of the present invention with reference to the accompanying drawings.

Description of drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.

Fig. 1 is a flowchart of an optimization method based on fusion of visible light communication and visible light positioning according to an embodiment of the present invention;

Fig. 2 is a structural principle diagram of an optimization system based on fusion of visible light communication and visible light positioning according to an embodiment of the present invention;

Fig. 3 is a schematic diagram of time-slicing of the integrated visible light communication and positioning method according to an embodiment of the present invention;

Fig. 4 is a schematic diagram of an uplink control frame in which a wireless local area network is used as an auxiliary communication mode in the integrated visible light communication and positioning method according to an embodiment of the present invention;

Fig. 5 is a schematic diagram of a downlink control frame in which a wireless local area network is used as an auxiliary communication mode in a method for integrating visible light communication and positioning according to an embodiment of the present invention.

Detailed ways

Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that the relative arrangements of components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise.

The following description of at least one exemplary embodiment is merely illustrative in nature and in no way taken as limiting the invention, its application or uses.

Techniques, methods and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such techniques, methods and devices should be considered part of the description.

In all examples shown and discussed herein, any specific values should be construed as exemplary only, and not as limitations. Therefore, other instances of the exemplary embodiment may have different values.

It should be noted that like numerals and letters denote like items in the following figures, therefore, once an item is defined in one figure, it does not require further discussion in subsequent figures.

The present invention is used in a visible light communication system, and the system includes a user or terminal equipment, multiple visible light units and a central controller (or central controller node). The communication between the terminal device and the visible light unit (or visible light communication unit) is realized, and the central controller node is used to uniformly schedule the visible light unit to improve the communication performance by changing its radiation distribution. For the sake of clarity, in the following description, an LED lamp is used as an example for the visible light unit, and an LED array corresponds to a plurality of visible light units.

Referring to FIG. 1 , the provided optimization method based on fusion of visible light communication and visible light positioning includes the following steps.

In step S1, the user performs indoor positioning and communication through visible light.

For example, the terminal device uses the photodiode to calculate the distance by the light power received by different visible light units, and uses the trilateral positioning method to perform visible light indoor positioning to determine the location information of the terminal device (such as indoor coordinates). The data stage collects data;

Step S2, sending location information to the central controller node.

For example, after obtaining the indoor positioning coordinates, the terminal device sends location information to the central controller node in uplink through the wireless local area network.

In step S3, the central controller node controls the visible light communication unit to change the indoor visible light radiation distribution.

For example, the central controller node controls the rotation of the visible light communication unit to change its rotation angle. By changing the rotation angle, the visible light unit can be aligned with the terminal device and the distribution of visible light radiation in the room can be changed.

Step S4, while the visible light broadcasts information, re-send the changed rotation angles of each unit downlink to the user.

For example, while the visible light is broadcasting information, the changed rotation angle of each visible light unit is fed back to the user in the downlink, and the visible light communication and positioning are completed and optimized by performing steps S1 to S4 in a loop.

Specific embodiments of the visible light unit, the terminal device and the central controller will be introduced in detail below.

As shown in FIG. 2 , the visible light unit includes a plurality of LED arrays, and the LED arrays are evenly distributed indoors to provide illumination, and the visible light unit can provide the function of visible light communication. Specifically, the visible light unit can modulate the data stream information into changes in light intensity through orthogonal frequency division multiplexing technology, and the changes in light intensity can be converted into photocurrent by photodiodes in the receiver (such as terminal equipment) When it is an electrical signal, it is recovered and the modulated information is demodulated. When realizing visible light positioning, the visible light units can blink sequentially on different units according to the time sequence change, and the ratio of the blinking time to the communication time can be uniformly scheduled by the central controller.

User terminal devices include but are not limited to smartphones, mobile tablet computers, virtual reality devices, and even any kind of IoT devices. The demodulation module of the terminal device uses a photodiode to demodulate the optical signal modulated on the visible light medium into a network data packet, and uses the decoded network data packet to extract the bit information flow, so as to further provide services for the application carried by the terminal device.

The user terminal equipment calculates the received signal strength by detecting the optical power of the photodiode during the positioning cycle. After obtaining the azimuth angle obtained by the inertial measurement unit on the terminal equipment, it obtains the distance from a single lighting unit by solving the radiation model, and then calculates multiple The indoor positioning coordinates are obtained according to the trilateration method.

Still combined with what is shown in FIG. 2 , the visible light unit is uniformly scheduled by a central controller. When performing network communication through the visible light unit, the Ethernet-to-light conversion needs to be completed first. Specifically, the data packets to be distributed by the network are changed from the original way of using radio waves as a medium on the physical layer to light waves, which are modulated in the visible light frequency band and sent to users as illuminating light containing information. For example, the central controller is composed of a Linux system, which can decide which visible light unit to schedule the network data packets to be distributed, and the visible light unit is composed of a communication module composed of FPGA to realize the modulation process of network data packets. In addition, in order to be able to adjust the radiation distribution of the visible light unit, each visible light unit can be placed on a mechanical pan-tilt that can rotate two-dimensionally. The pan-tilt is uniformly controlled and scheduled by the central controller, such as changing its pitch angle and yaw angle, so Implements a visible light unit that aligns its illuminated normals to surrounding points.

Figure 3 shows that in the broadcast communication of the LED lamp array unit, time division multiplexing and frequency hopping are used to coordinate multiple address communication and positioning. Specifically, in each time period, positioning and communication are performed separately, so as to realize multiplexing of visible light communication and positioning functions. And within the positioning period, all visible light units jump and turn off. For example, in the positioning period corresponding to T0 to T1, lamp 0 (that is, visible light unit 1) is extinguished, and the optical power of the terminal equipment is subtracted from the optical power of the extinguished light when it is fully on. The optical power relative to the lamp 0 can be obtained, and the distance between the terminal device and the lamp can be obtained by using the parameters of the radiation model. After multiple jumps of T1-T2, T2-T3, T3-T4, the distance to multiple lights can be obtained, and the indoor positioning coordinates can be obtained by trilateration. During the communication period in each cycle, the visible light unit broadcasts the information obtained by the central controller for Ethernet-to-light conversion, and all terminals in the room can decode the received information through photodiodes to realize visible light communication.

For example, the user detects the intensity of each visible light unit at each positioning block time, and calculates the distance L to the light according to the attenuation Pn of the intensity after the Nth light is extinguished, which can be obtained in each jump cycle The distance of a light, the position of the terminal can be calculated when it is performed for the third time, and the calculated position information can be sent up to the central controller.

FIG. 4 and FIG. 5 are schematic diagrams of auxiliary control frames for uplink and downlink communication using a wireless local area network in visible light communication. Due to the natural disadvantages of visible light communication technology, the transmission of its uplink and auxiliary control frames generally adopts the way of wireless local area network. The design standard is given in the media access control layer of IEEE 802.15.7 for indoor visible light communication using wireless local area network transmission. As shown in Figure 4 and Figure 5, the control frame, device ID, receiver address, sending unit address, filter address, sequence control information, optional address information and transmitted data packets include the FCS information of the cyclic redundancy check.

Compared with the prior art, the present invention integrates the positioning position of the terminal equipment and the attitude (attitude angle) of the equipment into its uplink media access control layer protocol, as shown in FIG. 4 . In the downlink media access control layer of the wireless local area network, as shown in Figure 5, the protocol incorporates the rotation angle of the visible light unit. Under this design, the rotation of the visible light unit changes the distribution of indoor radiation, and the rotation of each visible light unit changes the parameters (such as incident angle and radiation angle) used for positioning of the terminal device in the radiation model. This way of optimizing the media access control layer can make the optimization method proposed by the present invention run effectively.

Due to the rapid development of solid-state LED lights and their long luminous life, energy saving and environmental protection, they are widely used in indoor lighting. Moreover, since there are a large number of unlicensed communication bands in the visible light band and a single LED satisfies a Lambertian radiation model that can be quantified, visible light is widely studied as a communication technology and positioning technology. However, in the optical downlink, the communication quality varies greatly from location to location due to the inherent characteristics of Lambertian radiators. The source of communication fluctuations is the change of incident angle and radiation angle. Changing the direction of the user equipment to align it with the emission normal direction of the visible light communication unit can improve the overall space communication quality. And for terminal devices in an area, it is difficult to achieve precise positioning and communication at the edge of the line-of-sight of the visible light communication unit composed of LED lights, that is, the radiation model limits visible light transmission and positioning. However, the present invention rotates the visible light unit, The irradiation direction of the LED light can be changed, and it can be rotated according to the user's position, thereby effectively improving the accuracy of positioning and the communication rate of transmission.

In order to be able to schedule the rotation of the visible light communication unit, in one embodiment, a pan/tilt is used as a way to control its rotation. The gimbal is a device that can change the visible light communication unit it carries. Specifically, the gimbal can change the Euler angle (yaw angle, pitch angle) of the normal line illuminated by the visible light unit. These changes can be realized through an adjustable digital steering gear. The controller is uniformly scheduled.

For example, in the above step S3, the central controller schedules the rotation of each visible light platform, and after obtaining the position distribution of the terminal equipment, adjusts the rotation of each lamp to change the visible light radiation and maximize the communication rate. For example, for edge nodes in visible light, their own optical power is very weak, and they are in the blind area of communication and positioning. communication services. With the rotation of the visible light unit, the communication rate of the node with weak communication rate is enhanced.

For step S3, after the positioning position of the terminal device is obtained, the visible light units around the terminal device are scheduled to be aligned with the device so that it can obtain greater communication optical power. If the location of the device cannot be obtained under special circumstances, its approximate range can be obtained by detecting the optical power of the visible light unit, and the visible light unit around it is scheduled to rotate and continuously detect the optical power at this time, which can still provide gain for visible light communication . If in the case of a visible light communication blind area, the surrounding visible light units are scheduled to rotate to search for the location of the device, so that the fusion optimization method of visible light communication and positioning can continue.

In order to illustrate the optimization method proposed by the present invention, modeling analysis of the proposed model is carried out below. Specifically, under the spatial three-dimensional coordinates, the indoor visible light unit is abstracted into a single visible light unit and the end user in an end-to-end manner for end users, so as to establish a spatial geometric model between the mobile terminal and the sending end (visible light communication unit). In the geometric model that abstracts the end-to-end communication between the visible light unit and the end user, each visible light unit is equivalent to a source node, which satisfies the calculation of the optical power of the Lambertian radiator:

Wherein, A _p represents the receiving area of the photodiode, and φ represents the radiation angle of the visible light terminal to the communication device. LED lamps are an important part of visible light communication systems and can be regarded as Lambertian sources. In the Lambertian radiation model, the gain H _in of received optical power depends on the half-power angle θ1/2 of the LED lamp, the angle of incidence θ and the distance d _in between the receiver and the transmitter. The visible light receiving unit of the terminal is mainly composed of an optical filter, an optical amplifier composed of a Fresnel lens, and a photodiode. g(θ) and T _s (θ) are inherent gains of the optical filter and the Fresnel lens of the visible light receiving unit of the terminal, and will not change with the movement of the terminal. θ _F is the radiation angle range of the Lambertian radiator. When the angle between the line from the user's location to the visible light unit and the normal irradiated by the visible light unit is greater than θ _F , the terminal is considered unable to receive the visible light power, that is "Line-of-Sight Propagation of Visible Light". In the above formula, m is the Lambert series of the radiator, which can be measured by the following formula:

To sum up, in visible light communication, for a terminal object, its visible light receiving power is not only related to the half-power angle of the radiator, but also the distance between the radiator and the incident angle (the difference between the incident light and the normal direction of the object) angle), radiation angle (the angle between the line connecting the radiator to the terminal object and the normal direction of the radiator). Assuming that there are currently N objects in the room, for the visible light central controller, the visible light power that each object n can receive is:

Where C is a fixed constant for the visible light illumination unit, and Un is the distance between the terminal and the visible light communication unit. For all visible light units in the room, when using the frequency hopping transmission method proposed by the present invention (as shown in Figure 3 The time-division multiplexing method shown above), firstly, the time is allocated by cycle, and each cycle is divided into a communication cycle and a positioning cycle. In the positioning period of the time period T0-T1, the lamp 0 (visible light unit 1) is turned off during its positioning period, while the other lights are always on. In the subsequent period, each lamp jumps and goes out, and every time a lamp goes out , if the terminal is within the communication range of the unit, the distance between the terminal device and the light can be calculated according to the above model, expressed as:

减去在跳频传输时的可见光功率大小

既可以计算出d _in。在跳频闪烁多次后根据距离多个可见光单元的距离即可以通过三边测量法计算出此时的室内位置，用户光线的入射角和可见光单元的辐射角通过图4和图5的媒体访问层协议计算得出。对于室内的所有终端来说，其所接受到的总的光功率可以表示为： Among them, d _in is the distance from the i-th visible light unit to the n-th receiving terminal. After knowing the above-mentioned parameters, such as the radiation constant C of the visible light unit, the radiation angle and incident angle of the terminal relative to the visible light unit, and then pass when all Optical power when the visible light unit is always on

Subtract the visible light power during frequency hopping transmission

Both can calculate d _in . After multiple frequency hopping flashes, the indoor position at this time can be calculated according to the distance from multiple visible light units, and the incident angle of the user's light and the radiation angle of the visible light unit can be accessed through the media in Figure 4 and Figure 5 Layer protocol is calculated. For all terminals in the room, the total optical power they receive can be expressed as:

Wherein, i represents the number of the visible light unit, μ represents the number of the visible light unit, κ represents the number of terminal devices, and n represents the number of the terminal device.

In the optimization method proposed by the present invention, after establishing the above model, after traversing the nodes of the surrounding end users through each lamp, by searching for an optimal irradiation angle position on the pitch angle and yaw angle, by changing its visible light radiation unit At this point in the radiation angle, the optical power of visible light is increased, thereby improving the communication rate and positioning accuracy of visible light transmission.

In step S3, for an end user in any direction placed within the range of the visible light unit, the rotation of the visible light unit can optimize the sum of the communication rate, which can be obtained by traversing in the space of angles as mentioned above, and can realize the preset priority for this time Larger users provide better visible light communication services.

In step S3, when optimizing the communication rate, the central controller will not modulate information on units where the user cannot receive visible light information, so as to reduce energy loss caused by modulation.

In step S3, for an end user with any direction placed within the range of the visible light unit, since it is likely that the distance measurement cannot be realized for multiple visible light units, the positioning cannot be realized. Changing the rotation of multiple visible light units around it can increase the range of visible light irradiation and achieve a wider range of positioning.

In step S4, after scheduling the rotation of the visible light pan/tilt, for the end user, the radiation angle of the visible light unit has changed, and still using the unchanged visible light positioning radiation model at this time will lead to serious positioning errors. For this, the present invention proposes to send the attitude angle of the indoor visible light pan-tilt to the terminal user in real time. The specific implementation method is to inform the user of the angle of the visible light pan/tilt in real time in the media access control layer protocol (as shown in FIG. 4 ). The user performs visible light positioning again after obtaining the rotation angle of the visible light unit.

In step S1, after the change of the angle of the visible light communication unit is obtained through the indoor wireless local area network, the formula for calculating the distance is re-introduced to measure the distance between the terminal device and multiple visible light units. After measuring a small amount (less than 3) After the visible light distance, its approximate position can be estimated through the intensity range, and the rotation of the surrounding visible light units can be scheduled to search for its approximate range and realize the enhancement of communication. After measuring the distance from the visible light unit for three times or more, the precise indoor positioning can be obtained by trilateration. The visible light communication optimization method proposed by the present invention can provide terminal users with a higher rate without changing the communication power consumption, and only modulate and send information to the visible light unit communicating within the user's line of sight, so as to reduce the modulation requirements of the entire system. power consumption, and achieve a larger range of visible light communication and a larger range, more accurate visible light indoor positioning.

To sum up, in the present invention, the terminal device uses nearby visible light nodes as beacons, and realizes positioning by detecting the intensity of visible light signals emitted by the beacons while transmitting data through visible light communication. Moreover, when the terminal sends data in the uplink, it sends the positioning data to the central controller node of the indoor visible light center network. The controller dispatches the lighting direction of the visible light nodes through the distribution of indoor nodes to realize the optimization of visible light transmission at specific locations. In addition, the present invention enables the central controller to simultaneously provide users with visible light communication and positioning services by designing the media access control layer. In terms of efficiency, optimization for specific users can increase the downlink throughput rate, provide higher communication efficiency and reduce the power consumption of modulation, and can meet the needs of indoor precise positioning under the condition of reliable communication at the same time. In addition, the present invention uses the wireless local area network as a supplementary means of the control frame signal, which is of great significance for perfecting system functions and improving system robustness.

The present invention can be a system, method and/or computer program product. A computer program product may include a computer readable storage medium having computer readable program instructions thereon for causing a processor to implement various aspects of the present invention.

A computer readable storage medium may be a tangible device that can retain and store instructions for use by an instruction execution device. A computer readable storage medium may be, for example, but is not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of computer-readable storage media include: portable computer diskettes, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), or flash memory), static random access memory (SRAM), compact disc read only memory (CD-ROM), digital versatile disc (DVD), memory stick, floppy disk, mechanically encoded device, such as a printer with instructions stored thereon A hole card or a raised structure in a groove, and any suitable combination of the above. As used herein, computer-readable storage media are not to be construed as transient signals per se, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through waveguides or other transmission media (e.g., pulses of light through fiber optic cables), or transmitted electrical signals.

Computer-readable program instructions described herein may be downloaded from a computer-readable storage medium to a respective computing/processing device, or downloaded to an external computer or external storage device over a network, such as the Internet, a local area network, a wide area network, and/or a wireless network. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and/or edge servers. A network adapter card or a network interface in each computing/processing device receives computer-readable program instructions from the network and forwards the computer-readable program instructions for storage in a computer-readable storage medium in each computing/processing device .

Computer program instructions for carrying out operations of the present invention may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-related instructions, microcode, firmware instructions, state setting data, or Source or object code written in any combination, including object-oriented programming languages—such as Smalltalk, C++, Python, etc., and conventional procedural programming languages—such as the “C” language or similar programming languages. Computer readable program instructions may execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer, or entirely on the remote computer or server implement. In cases involving a remote computer, the remote computer can be connected to the user computer through any kind of network, including a local area network (LAN) or a wide area network (WAN), or it can be connected to an external computer (such as via the Internet using an Internet service provider). connect). In some embodiments, an electronic circuit, such as a programmable logic circuit, field programmable gate array (FPGA), or programmable logic array (PLA), can be customized by utilizing state information of computer-readable program instructions, which can Various aspects of the invention are implemented by executing computer readable program instructions.

Aspects of the present invention are described herein with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the invention. It should be understood that each block of the flowcharts and/or block diagrams, and combinations of blocks in the flowcharts and/or block diagrams, can be implemented by computer-readable program instructions.

These computer-readable program instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine such that when executed by the processor of the computer or other programmable data processing apparatus , producing an apparatus for realizing the functions/actions specified in one or more blocks in the flowchart and/or block diagram. These computer-readable program instructions can also be stored in a computer-readable storage medium, and these instructions cause computers, programmable data processing devices and/or other devices to work in a specific way, so that the computer-readable medium storing instructions includes An article of manufacture comprising instructions for implementing various aspects of the functions/acts specified in one or more blocks in flowcharts and/or block diagrams.

It is also possible to load computer-readable program instructions into a computer, other programmable data processing device, or other equipment, so that a series of operational steps are performed on the computer, other programmable data processing device, or other equipment to produce a computer-implemented process , so that instructions executed on computers, other programmable data processing devices, or other devices implement the functions/actions specified in one or more blocks in the flowcharts and/or block diagrams.

The flowchart and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present invention. In this regard, each block in a flowchart or block diagram may represent a module, a portion of a program segment, or an instruction that includes one or more Executable instructions. In some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks in succession may, in fact, be executed substantially concurrently, or they may sometimes be executed in the reverse order, depending upon the functionality involved. It should also be noted that each block of the block diagrams and/or flowchart illustrations, and combinations of blocks in the block diagrams and/or flowchart illustrations, can be implemented by a dedicated hardware-based system that performs the specified function or action , or may be implemented by a combination of dedicated hardware and computer instructions. It is well known to those skilled in the art that the realization through hardware, the realization through software and the combination of software and hardware are all equivalent.

Having described various embodiments of the present invention, the foregoing description is illustrative, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and alterations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principle of each embodiment, practical application or technical improvement in the market, or to enable other ordinary skilled in the art to understand each embodiment disclosed herein. The scope of the invention is defined by the appended claims.

Claims (10)

An optimization method based on fusion of visible light communication and visible light positioning, comprising the following steps: Step S10: The terminal device decodes the received modulation information of visible light communication, determines the identity of the visible light unit and calculates the optical power of the received multiple visible light units, and then determines the location information by using the trilateration method; Step S20: the terminal device embeds the location information in the media access layer protocol and sends it to the central controller; Step S30: Aiming at optimizing the communication performance between the terminal device and the visible light unit, the central controller controls and adjusts the radiation distribution of the relevant visible light unit according to the received position information, and feeds back the adjustment result to the terminal device via the media access layer protocol. The optimization method based on fusion of visible light communication and visible light positioning according to claim 1, characterized in that in step S10, for multiple visible light units, insert a segment of multiple beacons intermittent in timing in the media access layer protocol Stroboscopic, which forms a unique identification beacon for the terminal device in the time gap, and detects the visible light intensity according to the intermittent stroboscopic detection of the time sequence, uses the Lambertian radiation model to estimate the distance from multiple visible light units, and then determines the position information . The optimization method based on fusion of visible light communication and visible light positioning according to claim 1, characterized in that in step S30, the central controller schedules the Euler angles of the relevant visible light units according to the location information sent by the terminal equipment to control visible light communication radiation distribution. The optimization method based on fusion of visible light communication and visible light positioning according to claim 1, characterized in that, the sending end sends modulation information to the terminal device using an optional long and short time window allocation method, and transmits modulation information to the terminal device through the orthogonal frequency within the communication time window. The information required by the terminal equipment is multiplexed and modulated and broadcast through the visible light medium, and the division of the time window by the terminal equipment is set to be consistent with that of the sender. According to the optimization method based on the fusion of visible light communication and visible light positioning according to claim 1, it is characterized in that, for each visible light unit, after the central controller collects the position information sent by the terminal device in the uplink, it changes the position through the control of the pan/tilt Its Euler angle enables the relevant visible light unit to be oriented towards a specific terminal device. According to the optimization method based on the fusion of visible light communication and visible light positioning according to claim 1, it is characterized in that the receiving end of the terminal device is a photosensitive sensor, and the downlink wireless local area network and its own clock unit are used to make the time window and the central controller Within the communication time window, the receiving end performs OFDM demodulation on the received visible light information to obtain coded information; within the positioning time window, calculates the currently received light information through analog-to-digital conversion Power, and use the inertial measurement unit set on the terminal device to obtain the attitude angle of the terminal device, and calculate the distance between the terminal device and the visible light unit based on the received optical power, and then determine the position information of the terminal device, and regularly update the position information sent to the central controller. The optimization method based on the fusion of visible light communication and visible light positioning according to claim 1, wherein the visible light unit is composed of an LED lighting front section driven by a constant current power supply, used to send positioning and communication information, and controlled by the central controller Solve to obtain the current scheduling optimization strategy for each user resource allocation. The optimization method based on fusion of visible light communication and visible light positioning according to claim 1, characterized in that the sending of the position information and the adjustment result is realized by changing the auxiliary control frame of the wireless local area network. A computer-readable storage medium, on which a computer program is stored, wherein, when the program is executed by a processor, the steps of the method according to any one of claims 1 to 8 are realized. A computer device comprising a memory and a processor, wherein a computer program capable of running on the processor is stored on the memory, wherein any one of claims 1 to 8 is implemented when the processor executes the program The steps of the method described in the item.

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