Transmitting device applied to optical communication, and optical communication test method and device

Abstract

The application discloses a kind of applied to optical communication transmitting device and optical communication test method, equipment, transmitting device includes: at least two light emitting devices, light emitting device is used to emit light;Uniform light part is set to the light emitting side of the at least two light emitting devices, for making the emitted light of the at least two light emitting devices incident to uniform light part and scatter in uniform light part, so that the emitted light of the at least two light emitting devices mixes and emits from uniform light part;Light transmission part is set to the light emitting side of uniform light part, for making the emitted light of uniform light part increase angle after transmitting through light transmission part and emit.The application is emitted by multiple light emitting devices, the emitted light of multiple light emitting devices mixes by uniform light part, further makes angle increase after transmitting through light transmission part, so that the emission angle of the application is larger for the transmitting device applied to optical communication, makes the emitted light of transmitting device increase coverage, provides feasibility for wide coverage visible light communication.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of optical communication, in particular to a transmitting device applied to optical communication and an optical communication test method and equipment. BACKGROUND

[0002] At present, traditional wireless communication technology has been widely used in daily life, and the demand for wireless communication technology also shows exponential growth. However, the growth of demand for higher data rates, lower latency, increased capacity and multi-connection has brought major bottlenecks and challenges to wireless communication technology. Visible light communication (VLC) is expected to solve these problems. Unlike radio frequency communication, visible light communication has abundant spectrum resources, more stable anti-interference ability and stronger security. Most importantly, visible light communication can take advantage of existing lighting infrastructure to provide dual functions of lighting and communication, as an effective supplement to existing wireless networks, known as "light fidelity technology" (LiFi). In the past few decades, significant progress has been made in visible light communication research, and breakthroughs in communication rates have been achieved through optimization of transmitter and receiver devices, advances in modulation and equalization algorithms, and application of multi-input multi-output (MIMO) technology.

[0003] In the prior art, visible light communication is mainly used in point-to-point communication systems, using lasers such as laser diodes for transmitters, which have the advantages of high speed, long distance, high power, etc., enabling visible light communication systems to achieve robust wireless optical connectivity between transmitters and mobile receivers. However, the narrow beam and concentrated spot of laser light require precise alignment to achieve high-capacity transmission, which severely limits the mobility of the communication system. However, from the perspective of daily life scenarios, a widely covered communication system is essential for practical applications. Mobility is a basic advantage of wireless services, which provides flexibility and convenience for users, making it possible to connect while moving. In the mobile Internet era, people generally expect ubiquitous communication capabilities, and need a communication system that can adapt to mobility. SUMMARY

[0004] The purpose of the present application is to provide a transmitting device applied to optical communication, which increases the coverage range of the outgoing light of the transmitting device, providing feasibility for widely covered visible light communication. The present application also provides an optical communication test method and equipment.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0006] A transmitting device applied to optical communication, comprising:

[0007] at least two light emitting devices, the light emitting devices being configured to emit light;

[0008] a light homogenizing portion disposed on a light emitting side of the at least two light emitting devices, configured to make the light emitted by the at least two light emitting devices incident to the light homogenizing portion and scattered in the light homogenizing portion, so that the light emitted by the at least two light emitting devices is mixed and emitted from the light homogenizing portion;

[0009] a light transmitting portion disposed on a light emitting side of the light homogenizing portion, configured to make the light emitted by the light homogenizing portion transmitted through the light transmitting portion and then the angle of the light is increased and the light is emitted.

[0010] Optionally, the at least two light emitting devices are configured to emit at least one monochromatic light, or the at least two light emitting devices are configured to emit at least two monochromatic lights and the at least two monochromatic lights are mixed to form white light.

[0011] Optionally, the light emitting devices are configured to emit first waveband light;

[0012] Further comprising: a wavelength conversion layer disposed on a light emitting side of the light homogenizing portion, configured to make the first waveband light transmitted through the light homogenizing portion incident to the wavelength conversion layer, the wavelength conversion layer is excited to generate second waveband light;

[0013] The light transmitting portion is disposed on a light emitting side of the wavelength conversion layer, configured to make the first waveband light transmitted through the wavelength conversion layer and the second waveband light generated by the wavelength conversion layer transmitted through the light transmitting portion, and then the angle of the light is increased and the light is emitted.

[0014] Optionally, the wavelength conversion layer is disposed obliquely relative to the light homogenizing portion, the light transmitting portion is disposed on a first side, a second side or a third side of the wavelength conversion layer, the first side is on a side of the wavelength conversion layer opposite to the light homogenizing portion, the second side and the third side are opposite sides of the wavelength conversion layer, and the first waveband light reflected by the wavelength conversion layer is incident to the second side / third side.

[0015] Optionally, the light transmitting portion is disposed on the first side of the wavelength conversion layer, and a reflecting portion is disposed on the second side and / or the third side of the wavelength conversion layer, the reflecting portion is configured to reflect the first waveband light and the second waveband light from the wavelength conversion layer back to the wavelength conversion layer and further propagate to the light transmitting portion;

[0016] Or, the light transmitting portion is disposed on the second side of the wavelength conversion layer, and a reflecting portion is disposed on the first side and / or the third side of the wavelength conversion layer, the reflecting portion is configured to reflect the first waveband light and the second waveband light from the wavelength conversion layer back to the wavelength conversion layer and further propagate to the light transmitting portion;

[0017] Alternatively, the light-transmitting part is arranged at the third side of the wavelength conversion layer, and a reflecting part is arranged at the first side or / and the second side of the wavelength conversion layer, the reflecting part is used for reflecting the first-band light and the second-band light from the wavelength conversion layer back to the wavelength conversion layer and further propagating to the light-transmitting part.

[0018] Optionally, the reflecting part comprises a light collecting member and a reflecting layer, the reflecting layer is arranged at the side of the light collecting member away from the wavelength conversion layer, the light collecting member is used for making the first-band light and the second-band light from the wavelength conversion layer transmit to the reflecting layer, and making the first-band light and the second-band light reflected by the reflecting layer converge and return to the wavelength conversion layer.

[0019] A light communication test method applied to the transmitting device for optical communication in any one of the above embodiments, comprising:

[0020] During the process that the transmitting device emits the optical signal, moving the receiving device, changing the distance or / and the orientation of the receiving device relative to the transmitting device, and making the receiving device receive the optical signal;

[0021] According to the electrical signal generated after the receiving device receives the optical signal, obtaining the communication performance data, the communication performance data reflects the communication performance between the transmitting device and the receiving device.

[0022] Optionally, during the process that the transmitting device emits the optical signal, moving the receiving device, changing the distance or / and the orientation of the receiving device relative to the transmitting device comprises:

[0023] During the process that the transmitting device emits the optical signal, moving the receiving device at a constant speed along a straight track, and the transmitting device is on the central axis of the straight track;

[0024] Alternatively, the transmitting device is on the central axis of the straight track, and the distance between the transmitting device and the straight track is different, and during the process that the transmitting device emits the optical signal at any distance, moving the receiving device at a constant speed along the straight track.

[0025] Optionally, according to the electrical signal generated after the receiving device receives the optical signal, obtaining the communication performance data comprises: demodulating the electrical signal or / and calculating the bit error rate according to the electrical signal;

[0026] The demodulating the electrical signal comprises: processing and modulating the electrical signal, generating a constellation diagram, the constellation diagram comprising a plurality of constellation points, calculating the absolute distance between each element of the data to be recovered and each constellation point, and selecting the constellation point with the smallest absolute distance as the demodulated symbol;

[0027] The calculating the bit error rate according to the electrical signal comprises: processing the electrical signal to obtain an input binary stream, comparing the input binary stream with a demodulated output binary stream, finding the index of the bit mismatch, and calculating the bit error rate.

[0028] An optical communication test device comprises:

[0029] A track for mounting a receiving device and driving the receiving device to move along the track, the receiving device being used for receiving an optical signal emitted by a transmitting device and generating an electrical signal;

[0030] A mobile station for mounting the transmitting device and driving the transmitting device to move, the transmitting device being the transmitting device for optical communication as described in any one of the above.

[0031] A control device for obtaining communication performance data according to the electrical signal generated by the receiving device after receiving the optical signal.

[0032] According to the above technical solution, the transmitting device for optical communication comprises: at least two light emitting devices, the light emitting devices being used for emitting light; a light homogenizing part arranged on the light emitting side of the at least two light emitting devices, used for making the light emitted by the at least two light emitting devices incident to the light homogenizing part and scattered in the light homogenizing part, so that the light emitted by the at least two light emitting devices is mixed and emitted from the light homogenizing part; and a light transmitting part arranged on the light emitting side of the light homogenizing part, used for making the light emitted by the light homogenizing part pass through the light transmitting part and increase in angle and be emitted. The transmitting device for optical communication emits light through the plurality of light emitting devices, the light emitted by the plurality of light emitting devices is mixed through the light homogenizing part, and then the light is made to increase in angle by further passing through the light transmitting part, so that the emitting angle of the transmitting device for optical communication is large, the emitting light of the transmitting device is increased in coverage, and the feasibility of wide-coverage visible light communication is provided.

[0033] The optical communication test method and device provided by the application realize optical communication test on the transmitting device for optical communication. BRIEF DESCRIPTION OF DRAWINGS

[0034] In order to make the technical solutions in the present application or the prior art clearer, the accompanying drawings needed in the embodiments or prior art description will be briefly introduced. Obviously, the accompanying drawings in the following description only aim to some embodiments of the present application, and for those skilled in the art, other drawings can be obtained without creative effort.

[0035] Figure 1 A structure schematic diagram of a transmitting device applied to optical communication is provided for an embodiment of the present application.

[0036] Figure 2 A flowchart of an optical communication test method is provided for an embodiment of the present application.

[0037] Figure 3 A schematic diagram of a track and control device of an optical communication test equipment is provided for an embodiment of the present application.

[0038] Figure 4 A schematic diagram of an optical communication test performed by an optical communication test equipment is provided for an embodiment of the present application.

[0039] The reference signs in the accompanying drawings of the specification include:

[0040] 100-transmitting device, 101-light emitting device, 102-uniform light part, 103-wavelength conversion layer, 104-first lens, 105-second lens, 106-translucent part, 107-radiator, 108-receiving device, 109-mounting table, 110-track, 111-control device, 112-radiation fan. DETAILED DESCRIPTION

[0041] In order to make the technical solutions in the present application or the prior art clearer, the accompanying drawings needed in the embodiments or prior art description will be briefly introduced. Obviously, the accompanying drawings in the following description only aim to some embodiments of the present application, and for those skilled in the art, other drawings can be obtained without creative effort.

[0042] The present embodiment provides a transmitting device applied to optical communication, comprising:

[0043] At least two light emitting devices, the light emitting device is used for emitting light;

[0044] A uniform light part is arranged on the light emitting side of the at least two light emitting devices, used for making the emitted light of the at least two light emitting devices incident to the uniform light part and scattered in the uniform light part, so that the emitted light of the at least two light emitting devices is mixed and emitted from the uniform light part.

[0045] The light-transmitting part is arranged on the light-emitting side of the light-uniformizing part, and is used for increasing the angle of the light emitted by the light-uniformizing part after the light is transmitted through the light-transmitting part and then emitted.

[0046] The light emitted by the at least two light-emitting devices is incident to the light-uniformizing part, scattered in the light-uniformizing part when incident, mixed, and then emitted from the light-uniformizing part.

[0047] The light emitted by the light-uniformizing part is incident to the light-transmitting part and then emitted after being transmitted through the light-transmitting part. The angle of the light refers to the angle of the light relative to the optical axis, i.e., the included angle between the light and the optical axis. The angle of the light emitted by the light-uniformizing part is increased after the light is transmitted through the light-transmitting part, i.e., the angle of the light emitted by the light-uniformizing part relative to the optical axis is increased after the light is transmitted through the light-transmitting part, compared with the angle of the light emitted by the light-uniformizing part before the light is transmitted through the light-transmitting part.

[0048] The embodiment is applied to a transmitting device for optical communication, the light emitted by the multiple light-emitting devices is mixed by the light-uniformizing part, and then the angle of the light is increased after the light is transmitted through the light-transmitting part, so that the angle of the light emitted by the transmitting device for optical communication is large, the coverage of the light emitted by the transmitting device is increased, and the feasibility of the wide-coverage visible light communication is provided.

[0049] In some embodiments, the at least two light-emitting devices are used for emitting at least one kind of monochromatic light. The at least two light-emitting devices can emit one kind of monochromatic light, or the at least two light-emitting devices emit two or more kinds of monochromatic light. In actual application, the light communication scene and demand can be set according to the light communication scene and demand.

[0050] In some embodiments, the at least two light-emitting devices are used for emitting at least two kinds of monochromatic light, and the at least two kinds of monochromatic light are mixed to form white light, and the transmitting device for optical communication emits white light. Exemplarily, the at least two light-emitting devices can include a red light-emitting device, a green light-emitting device, and a blue light-emitting device, and the three light-emitting devices are arranged according to a set quantity ratio to form white light.

[0051] In some embodiments, the at least two light-emitting devices are arranged in an array form, and the light emitted by the at least two light-emitting devices is incident to the light-uniformizing part. In the embodiment, the arrangement form of the at least two light-emitting devices is not limited, and the at least two light-emitting devices can be, but are not limited to, arranged in a square array or a circular array.

[0052] In some embodiments, a heat sink is arranged on the non-light-emitting side of the at least two light-emitting devices, and the heat sink is used for transferring the heat generated by the light-emitting devices to the heat sink and dissipating the heat. The non-light-emitting end of the light-emitting device can be in contact with the heat sink. The heat sink can be, but is not limited to, a heat sink.

[0053] In some embodiments, the light emitting device can be a light emitting device emitting laser light, which has the performance of high power and high brightness, and the light emitting device can employ, but is not limited to, a laser diode.

[0054] The exit light of the at least two light emitting devices is incident to the light homogenizing part and scattered in the light homogenizing part, so that the exit light of the at least two light emitting devices is mixed, the exit light of the at least two light emitting devices is converted into a non-directional point light source, and the exit light is formed into a uniform wide-angle light source by scattering, thereby expanding the emission angle. Without the light homogenizing part, the exit light of each light emitting device will produce strong spot noise, which will make the light signal received by the receiving device unstable; the light may encounter different substances (such as particles in the air, water droplets, etc.) in the propagation path, resulting in scattering of the light, and these scattered light and unscattered light interfere with each other, causing the received light signal to be non-uniform; the light signal also has the possibility of passing through different paths (multipath propagation) to reach the receiving device in the transmission process, and the light signal propagates along different paths to reach the receiving device, and when the light waves of these different paths meet, interference may occur, resulting in fluctuations in the intensity of the light signal; the light homogenizing part can reduce these effects.

[0055] In some embodiments, the light homogenizing part is also used for making the exit light of the at least two light emitting devices incident to the light homogenizing part and scattered in the light homogenizing part, so that the exit light intensity of the light homogenizing part is uniform. By homogenizing the exit light of the at least two light emitting devices through the light homogenizing part, the spot noise is weakened, not only making the exit light of each light emitting device mixed uniformly, but also making the exit light intensity uniform after passing through the light homogenizing part. In some embodiments, the light homogenizing part can be a light homogenizing layer, and the layered structure makes the light mixing distance short, which helps to reduce the volume of the emitting device. The light homogenizing part can employ, but is not limited to, a scattering sheet.

[0056] In some embodiments, the light emitting device is used to emit first band light; the application of the transmitting device for optical communication further comprises: a wavelength conversion layer disposed on the light emitting side of the light homogenizing part, used to make the first band light passing through the light homogenizing part incident to the wavelength conversion layer, the wavelength conversion layer is excited to generate second band light; the light transmitting part is disposed on the light emitting side of the wavelength conversion layer, used to make the first band light passing through the wavelength conversion layer and the second band light generated by the wavelength conversion layer angle increase and emit after transmitting through the light transmitting part. The emitted light of the application of the transmitting device for optical communication is the mixed light of the first band light and the second band light. In this embodiment, the wavelength range of the first band light and the wavelength range of the second band light are not limited respectively, and can be set according to the application requirement in actual application. The wavelength conversion layer can generate a wider light emitting spectrum, and can generate a more smooth color transition. Compared with the mixed light of the multiple monochromatic light emitted by the at least two light emitting devices, the mixed light only depends on the emission of the light emitting device, which may cause the color profile of the mixed light to be sharp and not natural. In terms of structure design, the circuit of the multiple light emitting devices emitting multiple monochromatic light is more complex, and the circuit of the single light emitting device emitting the first band light is relatively simple. At the same time, by reducing the dependence on the multiple light emitting devices, the overall system loss can be reduced, and the service life can be improved.

[0057] In some embodiments, the wavelength conversion layer is disposed obliquely relative to the light homogenizing part, and the light transmitting part is disposed on the first side, the second side or the third side of the wavelength conversion layer, the first side is on the side opposite to the light homogenizing part, and the second side and the third side are opposite sides of the wavelength conversion layer, and the first band light reflected by the wavelength conversion layer is incident to the second side / third side. The wavelength conversion layer is disposed obliquely relative to the light homogenizing part, which means that the optical axis of the wavelength conversion layer is not parallel to the optical axis of the light homogenizing part.

[0058] The light transmitting part can be disposed on the first side of the wavelength conversion layer, i.e. on the side opposite to the light homogenizing part. The first band light passing through the light homogenizing part is incident to the wavelength conversion layer, irradiates the wavelength conversion layer to make it generate the second band light, and the second band light generated by the wavelength conversion layer and the first band light transmitting through the wavelength conversion layer are emitted from the light transmitting part. The light transmitting part can also be disposed on the second side / third side of the wavelength conversion layer. The first band light passing through the light homogenizing part is incident to the wavelength conversion layer, irradiates the wavelength conversion layer to make it generate the second band light, and the second band light generated by the wavelength conversion layer can be emitted from the light transmitting part disposed on the second side / third side of the wavelength conversion layer. If the first band light reflected by the wavelength conversion layer is incident to the second side / third side of the wavelength conversion layer, and the light transmitting part is disposed on the second side / third side of the wavelength conversion layer, the first band light reflected by the wavelength conversion layer can be emitted from the light transmitting part.

[0059] In some embodiments, the light-transmitting portion is disposed on the first side of the wavelength conversion layer, and a reflecting portion is disposed on the second side or / and the third side of the wavelength conversion layer, the reflecting portion being configured to reflect the first band of light and the second band of light from the wavelength conversion layer back to the wavelength conversion layer and further propagate to the light-transmitting portion. In this way, the light energy utilization rate can be improved, and the luminous intensity of the emitted light of the emitting device can be improved.

[0060] In some embodiments, the light-transmitting portion is disposed on the second side of the wavelength conversion layer, and a reflecting portion is disposed on the first side or / and the third side of the wavelength conversion layer, the reflecting portion being configured to reflect the first band of light and the second band of light from the wavelength conversion layer back to the wavelength conversion layer and further propagate to the light-transmitting portion. In this way, the light energy utilization rate can be improved, and the luminous intensity of the emitted light of the emitting device can be improved.

[0061] In some embodiments, the light-transmitting portion is disposed on the third side of the wavelength conversion layer, and a reflecting portion is disposed on the first side or / and the second side of the wavelength conversion layer, the reflecting portion being configured to reflect the first band of light and the second band of light from the wavelength conversion layer back to the wavelength conversion layer and further propagate to the light-transmitting portion. In this way, the light energy utilization rate can be improved, and the luminous intensity of the emitted light of the emitting device can be improved.

[0062] In some embodiments, the reflecting portion comprises a light collecting member and a reflecting layer, the reflecting layer being disposed on a side of the light collecting member away from the wavelength conversion layer, the light collecting member being configured to allow the first band of light and the second band of light from the wavelength conversion layer to pass through and be incident on the reflecting layer, and the reflecting layer being configured to reflect the first band of light and the second band of light out of the reflecting layer and converge the reflected first band of light and the second band of light to return to the wavelength conversion layer. The reflecting portion is provided with a light collecting member, and the reflected light is converged, which can avoid the light being directly reflected by the reflecting layer and scattered without output, so as to improve the luminous intensity of the emitted light of the emitting device. The light collecting member can be, but is not limited to, a lens.

[0063] For example, reference can be made to Figure 1 , For example, reference can be made to Figure 1 For example, reference can be made to

[0064] A first lens 104 is arranged on the first side of the wavelength conversion layer 103, and a reflective layer is arranged on the side of the first lens 104 away from the wavelength conversion layer 103. The second wavelength band light generated by the wavelength conversion layer 103 and the first wavelength band light that has passed through the wavelength conversion layer 103 are incident on the first lens 104 and are reflected back to the wavelength conversion layer 103. A second lens 105 is arranged on the second side of the wavelength conversion layer 103, and a reflective layer is arranged on the side of the second lens 105 away from the wavelength conversion layer 103. The second wavelength band light generated by the wavelength conversion layer 103 and the first wavelength band light that has been reflected by the wavelength conversion layer 103 are incident on the second lens 105 and are reflected back to the wavelength conversion layer 103. The optical axis of the wavelength conversion layer 103 and the optical axis of the light homogenizing portion 102 can form an angle of 45°. As shown in FIG. 1, the non-light-emitting end of each of the plurality of light-emitting devices 101 is in contact with the heat sink 107. Figure 1

[0065] In some embodiments, the wavelength conversion layer 103 can include a base layer and a wavelength conversion material arranged on the base layer. The wavelength conversion material includes, but is not limited to, phosphor. The base layer can be, but is not limited to, a glass base. For example, the light-emitting device 101 emits blue light, i.e., the first wavelength band light is blue light, the wavelength conversion layer 103 uses yellow phosphor glass, and the blue light emitted by the light-emitting device 101 and the light generated by the yellow phosphor glass under irradiation of the blue light are mixed into white light.

[0066] In this embodiment, the structure of the light-transmitting portion 106 is not limited, as long as the angle of the emitted light can be increased after the light has passed through the light-transmitting portion 106. The light from the light homogenizing portion 102 or the light from the wavelength conversion layer 103 is refracted and passes through the light-transmitting portion 106, which can further homogenize the light and increase the emission angle. The light-transmitting portion 106 can be a lens.

[0067] In some embodiments, the transmitting device for optical communication further includes a housing, the housing is provided with a light outlet, the light-emitting device 101 and the light homogenizing portion 102 are arranged in the housing, or the light-emitting device 101, the light homogenizing portion 102, the wavelength conversion layer 103, and the reflecting portion are arranged in the housing, and the light-transmitting portion 106 is arranged at the light outlet.

[0068] For example, in a specific example, the transmitting device is provided with a high-power blue laser array composed of 14 InGaN / GaN quantum well laser diodes as a light source, emits 452 nm blue light, and uses yellow phosphor glass as the wavelength conversion layer 103. A first lens, a second lens, and a third lens are arranged on the first side, the second side, and the third side of the wavelength conversion layer 103 in sequence, and each has a diameter of 25 mm and is a plano-convex lens. A transmitting device that emits white light is formed, has a wide field of view, and has an emission angle of 40°.

[0069] ​The embodiment also provides an optical communication test method, which is applied to the transmitting device for optical communication in any of the above embodiments, and can refer to Figure 2 , Figure 2 A flowchart of the optical communication test method provided by the embodiment is shown in the figure. The optical communication test method comprises the following steps:

[0070] S11: In the process of emitting the optical signal by the transmitting device, the receiving device is moved, the distance or / and the position of the receiving device relative to the transmitting device is changed, and the receiving device receives the optical signal;

[0071] S12: According to the electrical signal generated after the receiving device receives the optical signal, the communication performance data reflecting the communication performance between the transmitting device and the receiving device is obtained.

[0072] In the optical communication test method of the embodiment, the transmitting device for optical communication emits light through the plurality of light emitting devices, the light emitted by the plurality of light emitting devices is mixed through the light homogenizing part, and the light angle is increased after further passing through the light transmitting part, so that the transmitting angle of the transmitting device is large, the light emitted by the transmitting device increases the coverage range, and the feasibility of the wide coverage visible light communication is provided. The optical communication test method of the embodiment realizes the optical communication test on the transmitting device for optical communication.

[0073] In some embodiments, in the process of emitting the optical signal by the transmitting device, the receiving device is moved, and the distance or / and the position of the receiving device relative to the transmitting device is changed, which comprises: in the process of emitting the optical signal by the transmitting device, the receiving device is moved at a constant speed along a straight track, and the transmitting device is located on the central axis of the straight track. The transmitting device is located on the central axis of the straight track, the transmitting device emits the optical signal, and in this process, the receiving device moves at a constant speed along the straight track, and the receiving device receives the optical signal. Further, the communication performance data is obtained according to the electrical signal generated after the receiving device receives the optical signal, so that the communication test on the transmitting device is performed.

[0074] In some embodiments, the moving the receiving device, changing the distance or / and the orientation of the receiving device relative to the transmitting device during the process of the transmitting device emitting the optical signal comprises: the transmitting device is on the central axis of the straight track, and the distance between the transmitting device and the straight track is changed, and during the process of the transmitting device emitting the optical signal at any distance, the receiving device moves at a constant speed along the straight track. The distance between the transmitting device and the straight track is changed, and during the process of the transmitting device emitting the optical signal at any distance, the receiving device moves at a constant speed along the straight track, the receiving device receives the optical signal, and then the communication performance data is obtained according to the electrical signal generated after the receiving device receives the optical signal. For different distances between the transmitting device and the straight track, the communication performance data corresponding to each distance can be obtained. In this way, the communication test of the transmitting device is carried out.

[0075] In some embodiments, the obtaining the communication performance data according to the electrical signal generated after the receiving device receives the optical signal comprises: demodulating the electrical signal. The demodulating the electrical signal comprises: processing and modulating the electrical signal, generating a constellation diagram, the constellation diagram comprising a plurality of constellation points, for each element of the data to be recovered of the electrical signal, calculating the absolute distance between the element of the data to be recovered and each constellation point, and selecting the constellation point with the smallest absolute distance as the demodulated symbol. The demodulation process is mainly to find the minimum distance between the received signal and the complex mapping to recover the signal. In this way, the continuous signal can be converted back to the form of discrete symbols, that is, the analog signal is demodulated into a digital signal. In some embodiments, the received data can be processed by the LMS algorithm (least mean squares algorithm), which is an adaptive filtering algorithm. The constellation diagram can be generated by pulse amplitude modulation (PAM), and the constellation diagram represents the symbol sent by the transmitting device.

[0076] In some embodiments, the obtaining the communication performance data according to the electrical signal generated after the receiving device receives the optical signal comprises: calculating the bit error rate according to the electrical signal. The calculating the bit error rate according to the electrical signal comprises: processing the electrical signal to obtain an input binary stream, comparing the input binary stream with a demodulated output binary stream, finding the index of the bit mismatch, and calculating the bit error rate. The original data is preprocessed to obtain an input binary stream, which is compared with a demodulated output binary stream. All bit mismatch indexes are found, that is, the positions of all error bits are found and stored. The bit error rate (BER) is the ratio of the number of error bits to the total number of bits, which can be expressed as: BER = error bit number / total bit number.

[0077] In some embodiments, obtaining the communication performance data according to the electrical signal generated after the receiving device receives the optical signal comprises sampling the electrical signal. Sampling the electrical signal comprises sampling the electrical signal every preset number of samples, i.e. downsampling, which can reduce the computational burden. Exemplarily, one sample out of every two samples can be selected from the retimed received data for sampling. In actual applications, the electrical signal generated by the receiving device can be forwarded to an oscilloscope for sampling, and then demodulation and bit error rate (BER) calculation can be performed.

[0078] The embodiment also provides an optical communication test device, comprising:

[0079] a track 110 for mounting the receiving device 108 and driving the receiving device 108 to move along the track 110, wherein the receiving device 108 is configured to receive the optical signal emitted by the transmitting device 100 and generate an electrical signal;

[0080] a moving table for mounting the transmitting device 100 and driving the transmitting device 100 to move, wherein the transmitting device 100 is the transmitting device for optical communication according to any one of the above embodiments;

[0081] a control device 111 configured to obtain the communication performance data according to the electrical signal generated after the receiving device 108 receives the optical signal.

[0082] The optical communication test device of the embodiment can make the transmitting device for optical communication emit light through a plurality of light emitting devices, mix the light emitted by the plurality of light emitting devices through the light homogenizing part, further pass through the light transmitting part to increase the angle of the emitted light, so that the transmitting angle of the transmitting device is large, and the coverage of the emitted light of the transmitting device is increased, which provides feasibility for wide coverage visible light communication. The optical communication test device of the embodiment can realize optical communication test on the transmitting device for optical communication.

[0083] In some embodiments, the track 110 is provided with a mounting table 109, the receiving device 108 is mounted on the mounting table 109, and the mounting table 109 moves along the track 110 to drive the receiving device 108 to move along the track 110. The track 110 can be a straight track. In some embodiments, the mounting table 109 is connected to a motor, and the motor rotates to drive the mounting table 109 to slide on the track 110. The receiving device 108 can be, but is not limited to, a silicon photomultiplier (SiPM).

[0084] The mobile station can be a movable cart. In some embodiments, a cooling fan 112 is provided on one side of the transmitting device 100 to cool the transmitting device 100. The cooling fan 112 can be connected to the heat sink 107 of the transmitting device 100, and the heat generated by the transmitting device 100 is transferred to the heat sink 107, and the heat conducted by the heat sink 107 is further dissipated to the external environment by the cooling fan 112.

[0085] For example, reference can be made to Figure 3 and Figure 4 , Figure 3 A schematic diagram of a track and control device of an optical communication test equipment provided in an embodiment, Figure 4 A schematic diagram of an optical communication test performed by an optical communication test equipment provided in an embodiment. In a specific example, the track 110 is 1.2 m long, with a safety margin of 0.2 m at both ends, and the total movement range along the track 110 is 0.8 m, corresponding to coordinates 0-0.8 m. The motor rotates to drive the mounting table 109 to slide on the track 110, and the pitch of the synchronous belt is 162 mm per revolution, which means that when the speed is set to 1 S / r, the mounting table 109 moves 162 mm forward in one second. The control device 111 is located on one side of the track 110, allowing the mounting table 109 to move at different predetermined speeds.

[0086] The transmitting device 100 is mounted on a movable mobile station to change the distance between the transmitting device 100 and the receiving device 108, so as to study the mobile communication performance under different distances. Since the coverage range of the transmitting device 100 is wide, the entire track can be within the coverage range of the light spot, so that in theory, the receiving device 108 can communicate through the visible light link when moving along the track 110. The control device 111 adjusts the speed of the receiving device 108 moving along the track 110 through the motor, to realize the exploration of the influence on the received signal under different speed conditions.

[0087] Through experiments, when the emission angle of the transmitting device 100 is about 40°, the maximum communication rate can exceed 2.5 Gbps at a distance of 5 m. This research not only proves the feasibility of using a laser-based white light transmitting device for visible light communication applications and solid-state lighting, but also emphasizes the potential of advancing the development of next-generation optical wireless communication technology.

[0088] In these experiments, On-Off Keying (OOK) signals were transmitted at a rate of 500 Mbps. The system showed stable communication performance at distances of 1 meter and 2 meters, demonstrating adaptability to disturbances caused by movement. However, starting from 3 meters, the increase in distance and speed led to a larger fluctuation range of bit error rate (BER). At a distance of 4 meters, the system was still able to support a transmission rate of 500 Mbps at a speed of 0.48 m / s. This speed was chosen considering the need for mobile communication in indoor environments such as offices and classrooms. Despite the impact of distance and mobility on system performance, it maintained a certain degree of reliability. The transmission rate at 1 meter was 3.24 Gbps, and at a distance of 5 meters, the maximum communication rate could exceed 2.5 Gbps, covering an area of more than 10 m 2 The On-Off Keying (OOK) is a type of on-off modulation, which is simple and easy to use, suitable for low-speed and short-distance transmission scenarios.

[0089] The above describes the application of the transmitting device for optical communication and the optical communication test method and equipment provided by the present application in detail. In this paper, specific examples are used to explain the principles and implementation methods of the present application. The above examples are only used to help understand the method and core idea of the present application. It should be pointed out that for ordinary skilled persons in the art, without departing from the principles of the present application, the present application can be improved and modified in several ways, and these improvements and modifications also fall within the protection scope of the claims of the present application.

Claims

1. A transmitting device for optical communication, characterized by comprising: The application relates to a light-emitting device, which comprises: at least two light-emitting devices for emitting light; a light homogenizing part arranged on the light-emitting side of the at least two light-emitting devices, for making the light emitted by the at least two light-emitting devices incident on the light homogenizing part and scattered in the light homogenizing part, so that the light emitted by the at least two light-emitting devices is mixed and emitted from the light homogenizing part; a light-transmitting part arranged on the light-emitting side of the light homogenizing part, for making the light emitted by the light homogenizing part incident on the light-transmitting part and then increasing the angle and emitting the light; the light-emitting device is used for emitting first-waveband light; the application further comprises a wavelength conversion layer arranged on the light-emitting side of the light homogenizing part, for making the first-waveband light passing through the light homogenizing part incident on the wavelength conversion layer, the wavelength conversion layer is excited to generate second-waveband light, and the light-transmitting part is used for making the first-waveband light passing through the wavelength conversion layer and the second-waveband light generated by the wavelength conversion layer incident on the light-transmitting part and then increasing the angle and emitting the light; the wavelength conversion layer is arranged obliquely relative to the light homogenizing part, the light-transmitting part is arranged on the first side, the second side or the third side of the wavelength conversion layer, the first side is on the side opposite to the light homogenizing part of the wavelength conversion layer, the second side and the third side are opposite sides of the wavelength conversion layer, and the first-waveband light reflected by the wavelength conversion layer is incident on the second side / the third side; the light-transmitting part is arranged on the first side of the wavelength conversion layer, and a reflecting part is arranged on the second side and / or the third side of the wavelength conversion layer, the reflecting part is used for reflecting the first-waveband light and the second-waveband light from the wavelength conversion layer back to the wavelength conversion layer and further propagating to the light-transmitting part; or the light-transmitting part is arranged on the second side of the wavelength conversion layer, and a reflecting part is arranged on the first side and / or the third side of the wavelength conversion layer, the reflecting part is used for reflecting the first-waveband light and the second-waveband light from the wavelength conversion layer back to the wavelength conversion layer and further propagating to the light-transmitting part; or the light-transmitting part is arranged on the third side of the wavelength conversion layer, and a reflecting part is arranged on the first side and / or the second side of the wavelength conversion layer, the reflecting part is used for reflecting the first-waveband light and the second-waveband light from the wavelength conversion layer back to the wavelength conversion layer and further propagating to the light-transmitting part. 2.The transmitter for optical communication of claim 1, wherein, The at least two light-emitting devices are used for emitting at least one monochromatic light, or the at least two light-emitting devices are used for emitting at least two monochromatic lights, and the at least two monochromatic lights form white light after being mixed. 3.The transmitter for optical communication of claim 1, wherein, The reflecting part comprises a light collecting part and a reflecting layer, the reflecting layer is arranged on the side of the light collecting part away from the wavelength conversion layer, the light collecting part is used for making the first-waveband light and the second-waveband light from the wavelength conversion layer incident on the reflecting layer, and the first-waveband light and the second-waveband light reflected by the reflecting layer are converged and returned to the wavelength conversion layer.

4. An optical communication test method applied to the transmission device for optical communication according to any one of claims 1 to 3, characterized in that, The application relates to a light-emitting device, which comprises: moving the receiving device during the process of the transmitting device emitting the optical signal, changing the distance or / and the orientation of the receiving device relative to the transmitting device, and making the receiving device receive the optical signal; obtaining communication performance data according to the electrical signal generated after the receiving device receives the optical signal, the communication performance data reflecting the communication performance between the transmitting device and the receiving device.

5. The optical communication test method of claim 4, wherein, moving the receiving device during the process of the transmitting device emitting the optical signal, changing the distance or / and the orientation of the receiving device relative to the transmitting device includes: moving the receiving device at a constant speed along a straight track during the process of the transmitting device emitting the optical signal, the transmitting device being located on the central axis of the straight track; alternatively, the transmitting device being located on the central axis of the straight track and being located at different distances from the straight track, and moving the receiving device at a constant speed along the straight track during the process of the transmitting device emitting the optical signal at any distance.

6. The optical communication test method according to claim 4, wherein obtaining communication performance data according to the electrical signal generated after the receiving device receives the optical signal includes demodulating the electrical signal or / and calculating the bit error rate according to the electrical signal; demodulating the electrical signal includes processing and modulating the electrical signal, generating a constellation diagram, the constellation diagram including a plurality of constellation points, for each element of the data to be recovered of the electrical signal, calculating the absolute distance between the element of the data to be recovered and each constellation point, and selecting the constellation point with the smallest absolute distance as the demodulated symbol; calculating the bit error rate according to the electrical signal includes processing the electrical signal to obtain an input binary stream, comparing the input binary stream with the demodulated output binary stream, finding the index of the bit mismatch, and calculating the bit error rate.

7. An optical communication test apparatus characterized by comprising: comprise: a track for mounting the receiving device and driving the receiving device to move along the track, the receiving device being used for receiving the optical signal emitted by the transmitting device and generating an electrical signal; a moving platform for mounting the transmitting device and driving the transmitting device to move, the transmitting device being the transmitting device for optical communication according to any one of claims 1 to 3; a control device for obtaining communication performance data according to the electrical signal generated after the receiving device receives the optical signal.

Images