Illuminating lamp data transmission method

Abstract

The invention is suitable for the technical field of data processing, and provides an illumination lamp data transmission method, which comprises the following steps that: an illumination lamp continuously acquires various parameter data in the environment and during working, encodes and modulates the various acquired parameter data, and then loads the encoded and modulated parameter data to a power line for data transmission; the PLC concentrator receives modulation signals sent by a plurality of lighting lamps from the power line, demodulates and recovers the modulation signals into various original parameter data, and forwards the various parameter data to the connected LPWAN gateway; the LPWAN gateway recodes and packs the received various parameter data, and transmits the packed data to a monitoring center through an LPWAN network; and the monitoring center receives the packed data transmitted through the LPWAN network, demodulates and recovers the packed data into various parameter data of the lighting lamp, and monitors and analyzes the various parameter data of the lighting lamp. The problem that an existing lighting lamp is poor in data transmission signal stability in a special environment where communication is inconvenient is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of data processing, and in particular to a method for transmitting data of a lighting fixture. Background Art

[0002] In special environments such as mines and tunnels, as production safety standards improve, the role of lighting fixtures is no longer limited to providing basic lighting. In order to ensure the safety of underground operations, lighting fixtures must be integrated with data transmission functions to monitor various parameters of the mine environment (such as air quality, temperature and humidity, personnel positioning, etc.) in real time, so as to effectively prevent potential dangers.

[0003] However, mine environments are generally characterized by high humidity, high dust, and complex electromagnetic interference, which results in the inability of traditional wireless communication technologies (such as Wi-Fi, Bluetooth, etc.) to provide reliable and stable communication links in such scenarios. This environmental characteristic places higher demands on data transmission, especially stability, coverage, and anti-interference capabilities.

[0004] In addition, current mines are usually widely distributed, with numerous lighting nodes and complex layouts. Traditional wireless communication systems are prone to problems such as signal attenuation, data packet loss and delay when used in a large range of applications. It is difficult to meet the needs of real-time data transmission in special environments such as mines and underground spaces, and has failed to effectively solve the problems of real-time data transmission and large-scale stable coverage. Summary of the invention

[0005] Based on this, the purpose of the present invention is to provide a lighting fixture data transmission method to fundamentally solve the problem of poor stability of data transmission signals of existing lighting fixtures in special environments where communication is inconvenient.

[0006] A method for transmitting lighting fixture data according to an embodiment of the present invention includes:

[0007] The lighting fixture continuously collects various parameter data of the environment and working state, and encodes and modulates the collected parameter data and loads them onto the power line for transmission;

[0008] The PLC hub receives modulated signals sent by multiple lighting fixtures from the connected power lines, demodulates and restores them into original parameter data, and forwards the parameter data to the connected LPWAN gateway;

[0009] The LPWAN gateway re-encodes and packages the various parameter data received from the PLC hub and transmits the packaged data to the monitoring center via the LPWAN network;

[0010] The monitoring center receives the packaged data transmitted through the LPWAN network, demodulates and restores it into various parameter data of the lighting fixtures, and monitors and analyzes the various parameter data of the lighting fixtures.

[0011] In addition, the lighting fixture data transmission method according to the above embodiment of the present invention may also have the following additional technical features:

[0012] Furthermore, the step of encoding and modulating the collected various parameter data and then loading them onto the power line for transmission includes:

[0013] The lighting fixture converts, packages and encodes the collected parameter data into digital data;

[0014] The lighting fixtures monitor the channel status on the power line in real time and dynamically adjust the modulation parameters according to the channel status;

[0015] The lighting fixture modulates the encoded digital data into a modulation signal transmitted on the power line according to the adjusted modulation parameters;

[0016] The lighting fixture superimposes the modulated signal on the current of the power line for transmission.

[0017] Furthermore, the steps of the PLC hub receiving modulated signals sent by a plurality of lighting fixtures from the connected power line, demodulating and restoring the signals into the original various parameter data include:

[0018] The PLC hub receives modulation signals sent by a plurality of lighting fixtures from the connected power line, and identifies the modulation mode used by the modulation signal according to the signal characteristics of the modulation signal, wherein the signal characteristics include phase, frequency and amplitude;

[0019] The PLC hub monitors the channel status on the power line in real time and adjusts the demodulation parameters according to the dynamic changes of the channel status;

[0020] The PLC hub demodulates the modulated signal and restores it to the original parameter data according to the demodulation method corresponding to the modulation method and the adjusted demodulation parameters.

[0021] Furthermore, the step of transmitting the packaged data to the monitoring center through the LPWAN network includes:

[0022] The LPWAN gateway dynamically adjusts the transmission power and rate of the packaged data transmitted to the monitoring center based on the real-time monitoring of the transmission conditions of the LPWAN network;

[0023] The LPWAN gateway dynamically adjusts the size of the sub-packets into which the packaged data is divided based on real-time monitoring of the network load and signal strength of the LPWAN network.

[0024] Furthermore, the step of encoding and modulating the collected various parameter data and then loading them onto the power line for transmission includes:

[0025] The lighting fixture encodes and modulates the collected parameter data and then loads it onto the power line for transmission in the allocated specific time slot or specific frequency band;

[0026] The steps of receiving the modulated signals sent by the plurality of lighting fixtures from the connected power lines by the PLC hub, demodulating and restoring the signals into the original various parameter data include:

[0027] The PLC hub receives modulated signals in different time slots or frequency bands from the connected power line, determines the identity of the corresponding lighting fixture according to the time slot or frequency band to which each modulated signal belongs, and demodulates various parameter data of each lighting fixture.

[0028] Furthermore, the lighting fixture converts, packages and encodes the collected parameter data into digital data, including:

[0029] The lighting fixture converts the collected parameter data into parameter data of digital signals;

[0030] The lighting fixture packages the parameter data of the digital signal into a data frame, wherein the data frame includes a source address, a target address, data content and a check code;

[0031] The lighting fixture encodes the data frame as digital data.

[0032] Furthermore, the step of the lighting fixture superimposing the modulated signal on the current of the power line for transmission includes:

[0033] The lighting fixture listens to the power line to see if there are other lighting fixtures transmitting data;

[0034] If yes, then continue to listen to whether there are other lighting fixtures transmitting data on the power line after waiting for a random time, until there are no other lighting fixtures transmitting data on the power line;

[0035] If not, the modulated signal is superimposed on the current of the power line for transmission.

[0036] Furthermore, the steps of the PLC hub receiving modulated signals sent by a plurality of lighting fixtures from the connected power line, demodulating and restoring the signals into the original various parameter data include:

[0037] The PLC hub receives the modulated signal sent by the lighting fixture from the connected power line and demodulates it into the parameter data of the original digital signal;

[0038] The PLC hub decodes the digital data into data frames, identifies the source address, destination address, data content and checksum based on the data frames, and matches them based on the destination address;

[0039] If the match is successful, the identity of the corresponding lighting fixture is determined according to the source address and various parameter data of the lighting fixture is determined according to the data content.

[0040] Furthermore, after the step of monitoring and analyzing various parameter data of the lighting fixture, the step further includes:

[0041] The monitoring center sends the control instructions for controlling the target lighting fixtures to the LPWAN gateway through the LPWAN network;

[0042] The LPWAN gateway receives the control instructions transmitted by the monitoring center, decodes them and transmits them to the PLC hub;

[0043] The PLC hub receives the control instructions transmitted by the LPWAN gateway, packages, encodes and modulates the control instructions, and then loads them onto the power line for transmission;

[0044] The target lighting fixture receives the modulated signal sent by the PLC hub from the power line, demodulates and restores it to the original control instruction, and performs corresponding work control according to the control instruction.

[0045] Furthermore, after the step of monitoring and analyzing various parameter data of the lighting fixture, the step further includes:

[0046] The monitoring center determines whether the various parameter data of the lighting fixture exceeds the corresponding preset threshold value;

[0047] If so, the monitoring center determines whether to generate an alarm message to issue an alarm or generate a control instruction to control the lighting fixture according to the type of parameter data that exceeds the preset threshold.

[0048] The lighting fixture data transmission method provided by the embodiment of the present invention uses PLC technology to transmit data through power lines through lighting fixtures, which can avoid signal interference and shielding problems that may be faced by traditional wireless communication methods in complex electromagnetic environments, and is particularly suitable for environments with high humidity, high dust and complex electromagnetic interference such as mines and tunnels; and uses the LPWAN network to transmit data to the monitoring center through the LPWAN gateway. Since LPWAN has the characteristics of long distance, wide coverage, and low power consumption, stable data transmission can be achieved in a large range; since PLC technology has the advantages of high data transmission rate and low latency within a short distance, data aggregation of local lighting equipment is performed through power lines, which reduces signal attenuation and packet loss problems, and LPWAN technology expands the coverage range, ensures data transmission stability in long-distance environments, and solves the problem of poor data transmission signal stability of existing lighting fixtures in special environments with inconvenient communication. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 is a flow chart of a lighting fixture data transmission method in a first embodiment of the present invention;

[0050] The following specific implementations will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0051] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. Several embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

[0052] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0053] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0054] Embodiment 1

[0055] See also Figure 1, which shows a lighting fixture data transmission method in a first embodiment of the present invention. For the sake of convenience, only the parts related to the embodiment of the present invention are shown. The lighting fixture data transmission method provided by the embodiment of the present invention includes:

[0056] Step S10, the lighting fixture continuously collects various parameter data of the environment in which it is located and when it is working, and encodes and modulates the collected various parameter data and then loads them onto the power line for transmission;

[0057] Among them, in one embodiment of the present invention, the lighting fixture data transmission method is applied to special environments such as mines and tunnels where communication is inconvenient, wherein the lighting fixture data transmission method involves multiple lighting fixtures, multiple PLC hubs, multiple LPWAN gateways, and a monitoring center, and each lighting fixture is distributed in each area of ​​the special environment such as the mine and tunnel in which it is applied, so that each lighting fixture can collect various parameter data of the environment and when working. The various parameter data include environmental parameter data such as ambient temperature, humidity, gas concentration, and working parameter data such as voltage, current, and working state of the lighting fixture. Specifically, multiple sensors are integrated inside the lighting fixture to collect various environmental parameter data of the current environment and various working parameter data of the lighting fixture when it is working. The sensors specifically include: a temperature sensor for collecting temperature data of the environment where the lighting fixture is located; a humidity sensor for collecting humidity data of the environment where the lighting fixture is located; a gas concentration sensor for collecting gas concentration data in the air of the environment where the lighting fixture is located; a voltage sensor for collecting voltage data when the lighting fixture is working; a current sensor for collecting current data when the lighting fixture is working; a power sensor for collecting actual power consumption when the lighting fixture is working; and a lamp status acquisition module for collecting working status data such as the switch status, light intensity, operating time and fault information of the lighting fixture.

[0058] Furthermore, the step of encoding and modulating the collected various parameter data and then loading them onto the power line for transmission includes:

[0059] The lighting fixture converts, packages and encodes the collected parameter data into digital data;

[0060] The lighting fixtures monitor the channel status of each frequency band on the power line in real time and dynamically adjust the modulation parameters according to the channel status;

[0061] The lighting fixture modulates the encoded digital data into a modulation signal transmitted on the power line according to the adjusted modulation parameters;

[0062] The lighting fixture superimposes the modulated signal on the current of the power line for transmission.

[0063] Furthermore, the steps of converting, packaging and encoding the collected parameter data into digital data by the lighting fixture include:

[0064] The lighting fixture converts the collected parameter data into parameter data of digital signals;

[0065] The lighting fixture packages the parameter data of the digital signal into a data frame, wherein the data frame includes a source address, a target address, data content and a check code;

[0066] The lighting fixture encodes the data frame as digital data.

[0067] Among them, the parameter data collected by the above-mentioned sensor is usually an analog signal (such as temperature, current, etc.), so it is first necessary to convert the collected analog signal of the sensor into the parameter data of the digital signal (for example, using an analog-to-digital converter ADC). In order to effectively transmit data, the parameter data of the digital signal needs to be packaged into a data frame. The data frame structure usually includes a source address, a target address, data content and a check code, wherein the source address represents the address of the sender of the data (the identity of the lighting fixture); and the target address represents the address of the receiver of the data (the identity of the PLC hub); and the data content encapsulates the parameter data collected by the lighting fixture; the check code is used to detect whether the data has been tampered with or erroneous during transmission. Commonly used check techniques include cyclic redundancy check (CRC) or parity check. At this time, the data packaging process is usually to add a frame header, encapsulate the data content and attach a check code, wherein the frame header part includes the source address and the target address information, indicating the identity of the sender and the receiver of the data packet. The encapsulated data content is to place the parameter data of the digital signal in the data field of the data frame. Then the check code of the data field is calculated and attached to the end of the data frame. The check code can ensure the integrity and accuracy of the data at the receiving end. After being packaged into a data frame, the data frame needs to be converted into digital data suitable for modulation and transmission, so that the binary data can be converted into a symbol sequence suitable for transmission through the power line after encoding. Commonly used encoding technologies include Manchester encoding, NRZ (non-return-to-zero encoding), differential binary phase shift keying (DBPSK) or error detection encoding (such as Hamming code, convolutional code, etc.). Different encoding methods will affect the transmission rate and anti-interference of the data. In an embodiment of the present invention, Manchester encoding can be specifically adopted, which improves the anti-noise ability of the signal by converting the signal of each bit into a change of high and low levels. At the same time, the encoded data frame can contain synchronization information to ensure that the receiving end correctly identifies the beginning and end of the data frame. At the same time, in some cases, the data can also be compressed to reduce the amount of data and improve the transmission efficiency.

[0068] Furthermore, the lighting fixture monitors the channel status on the power line in real time. Specifically, the lighting fixture obtains the channel status information through the feedback signal and sampling on the power line. The channel status monitoring includes real-time detection of the communication quality of the power line and evaluation of the channel status by measuring the key parameters in the channel. Common channel status parameters include signal-to-noise ratio (SNR), interference level and attenuation, wherein the signal-to-noise ratio (SNR) is the strength ratio of the signal to the noise. The interference level is to detect the power line noise and interference that may be caused by other devices. Attenuation is the attenuation of the signal as it propagates in the power line with the distance. Then, the modulation parameters are dynamically adjusted according to the channel status to adapt to the transmission conditions of the power line. The parameters that can be dynamically adjusted include the modulation mode, frequency band and transmission power. At this time, QAM, PSK or other modulation modes can be selected according to the channel status. Or the frequency range used can be adjusted according to the interference situation. Or the transmission power can be increased or decreased according to the signal attenuation. For example, when the channel condition is good, a higher-order modulation mode (such as 16-QAM, 64-QAM) is used to increase the data transmission rate. In the case of low signal-to-noise ratio and strong interference, it is possible to switch to a lower-order modulation method (such as BPSK, QPSK) to ensure the reliability of transmission. The encoded digital data is then modulated onto the modulation signal according to the selected modulation parameters, where the core purpose of the modulation is to convert the digital data into a high-frequency analog signal that can be transmitted on the power line. At this time, the encoded data is modulated into a high-frequency signal suitable for power line transmission. For example, the binary data "1010" can be mapped to a signal waveform of different frequencies or phases through the corresponding modulation scheme. The modulated signal is superimposed on the current of the power line for transmission, and this process is usually achieved through a coupler. The coupler is responsible for loading the high-frequency communication signal onto the power line current, while ensuring that the alternating current (usually 50 / 60Hz) on the power line does not interfere with the communication signal. The modulated signal is transmitted to the receiving end (PLC hub) through the power line. At this time, the power line not only transmits electrical energy, but also carries the modulated data signal, so that the normal power supply function of the power line is not affected during data transmission. Therefore, the modulated signal is transmitted through the existing power lines, and the transmitted data flows in the power lines with the current, without the need to lay new data transmission cables, so that it can effectively cross the physical obstacles in the mine, and there is no need to lay additional communication lines, which reduces the wiring cost and can adapt to the complex electromagnetic environment of the mine.

[0069] Further, in one embodiment of the present invention, the above-mentioned encoding and modulating the collected various parameter data and then loading them onto the power line for transmission includes two implementation methods, wherein in the first implementation method, the steps specifically include:

[0070] The lighting fixture encodes and modulates the collected parameter data and then loads it onto the power line for transmission in the allocated specific time slot or specific frequency band;

[0071] The PLC hub receives modulated signals sent by a plurality of lighting fixtures from the connected power line.

[0072] Specifically, if the method in the embodiment of the present invention adopts the time division multiple access (TDMA) mechanism, each lighting fixture will be assigned a specific time window, that is, a time slot. Only within this time slot can the lighting fixture send data to the power line, so that conflicts can be avoided when multiple lighting fixtures send data at the same time. If the method in the embodiment of the present invention adopts the frequency division multiple access (FDMA) mechanism, each lighting fixture is assigned a specific frequency bandwidth. At this time, different lighting fixtures transmit data simultaneously on different frequency bands to avoid interference. At this time, according to the time slot or frequency band where the lighting fixture is located, the encoded digital data will dynamically adjust the appropriate modulation method according to the channel state and convert it into a modulated signal. The modulated signal is superimposed on the current of the power line through a coupler and transmitted using the power line. At this time, the parameter data of each lighting fixture is loaded to the power line at its assigned time slot or frequency band.

[0073] In the second implementation, the steps specifically include:

[0074] The lighting fixture listens to the power line to see if there are other lighting fixtures transmitting data;

[0075] If yes, then continue to listen to whether there are other lighting fixtures transmitting data on the power line after waiting for a random time, until there are no other lighting fixtures transmitting data on the power line;

[0076] If not, the modulated signal is superimposed on the current of the power line for transmission.

[0077] Specifically, when the lighting fixture is preparing to send data, it first needs to listen to the communication status on the power line. It monitors the current signal in the power line in real time to check whether there are other lighting fixtures transmitting data. The listening process usually depends on detecting whether there is a carrier modulated by the signal on the power line, which can be achieved by energy detection (EnergyDetection) or specific signal mode detection (for example, checking the modulation signal characteristics). The energy detection method determines whether there is a carrier signal by analyzing the signal strength of different frequency bands on the power line. If there is signal transmission on the power line, the detected energy will exceed the preset threshold. The specific signal mode detection method is that the detection module demodulates and analyzes the signal on the power line, and when it detects that the signal conforms to the preset transmission format or a specific frequency mode, it determines that there are other lighting fixtures transmitting data on the power line. If the lighting fixture detects that there are other lighting devices transmitting data in the power line, it enters the waiting mode, that is, temporarily does not perform the signal sending operation to avoid data collision until the power line is idle. After waiting for a random period of time, the power line status is listened again. The random waiting time can prevent multiple lighting fixtures from sending data again at the same time after detecting that the line is idle at the same time, thereby further avoiding collision. In order to avoid channel contention conflicts, a random backoff mechanism is introduced (similar to the backoff algorithm in the CSMA / CA mechanism). Specifically, after each lighting fixture detects that the power line is idle, it does not start transmitting immediately, but waits for a random time interval to reduce the possibility of multiple lighting fixtures starting to transmit at the same time. The time interval can be dynamically adjusted according to the number of lighting fixtures on the power line. When re-listening, if it is found that there are no other devices transmitting data on the power line, the lighting fixture will immediately superimpose the modulated signal on the current of the power line for transmission. The modulated signal is loaded into the current of the power line through a coupler, and the power line is used as a transmission medium for communication, so that the frequency band resources of the power line can be effectively utilized.

[0078] Step S20, the PLC hub receives modulated signals sent by multiple lighting fixtures from the connected power line, demodulates and restores the signals into original parameter data, and forwards the parameter data to the connected LPWAN gateway;

[0079] In one embodiment of the present invention, the steps of receiving the modulated signals sent by the plurality of lighting fixtures from the connected power line by the PLC (Power Line Communication) hub, demodulating and restoring the signals into the original various parameter data include:

[0080] The PLC hub receives modulation signals sent by a plurality of lighting fixtures from the connected power line, and identifies the modulation mode used by the modulation signal according to the signal characteristics of the modulation signal, wherein the signal characteristics include phase, frequency and amplitude;

[0081] The PLC hub monitors the channel status on the power line in real time and adjusts the demodulation parameters according to the dynamic changes of the channel status;

[0082] The PLC hub demodulates the modulated signal and restores it to the original parameter data according to the demodulation method corresponding to the modulation method and the adjusted demodulation parameters.

[0083] Specifically, the PLC hub is connected to the power line through a power line coupler to receive the modulated signal emitted by the lighting fixture. The function of the power line coupler is to separate the modulated signal from the high-frequency part of the power line and suppress the low-frequency power signal of the power line to avoid interference. The receiving module of the PLC hub samples the analog signal received from the power line coupler at high speed. The analog signal is converted into a discrete digital signal through an analog-to-digital converter (ADC). At this time, the signal still retains the original phase, frequency and amplitude characteristics. Further, the PLC hub analyzes the received signal to extract the frequency characteristics of the signal. Through technologies such as fast Fourier transform (FFT), the PLC hub can determine the carrier frequency and frequency band occupancy used by the signal. In addition to the frequency, the hub also identifies the modulation mode by detecting the phase and amplitude. Common modulation modes include PSK (phase shift keying), QAM (quadrature amplitude modulation), and OFDM (orthogonal frequency division multiplexing). By detecting the change in phase, the PLC hub can identify the PSK modulated signal. By analyzing amplitude and phase simultaneously, the PLC hub can identify QAM signals. By detecting the frequency occupancy of multi-carrier signals, the PLC hub can identify OFDM modulation. At this time, through the joint analysis of signal frequency, phase and amplitude, the PLC hub can automatically identify the modulation mode of the signal and record the modulation mode used by each lighting fixture to facilitate subsequent demodulation operations. Further, the PLC hub monitors the channel status of the power line in real time. When the channel status changes significantly (such as a decrease in signal-to-noise ratio, an increase in interference, etc.), the PLC hub can detect these changes and evaluate whether the transmission conditions have deteriorated. Then, based on the changes in the channel status monitored in real time, the PLC hub dynamically adjusts the demodulation parameters to adapt to the current channel conditions. The specific adjustments include filter adjustment, gain control, clock and synchronization adjustment, among which filter adjustment is to adjust the bandwidth of the hub's digital filter to better adapt to the signal characteristics in the spectrum and eliminate interference. Gain control is that the automatic gain control (AGC) module dynamically adjusts the amplification factor of the received signal according to the degree of signal attenuation to ensure that the signal is demodulated at a better level. Clock and synchronization adjustment is in a dynamically changing channel. The PLC hub adjusts the clock synchronization in real time to ensure the accuracy of data sampling and symbol recovery. Once the modulation method of the signal is identified and the demodulation parameters are adjusted, the PLC hub will restore the original data according to the corresponding demodulation method. The specific process is as follows: For phase-modulated signals (such as PSK), the hub restores the original bit stream through a phase demodulation algorithm. For amplitude-modulated signals (such as QAM), the hub recovers the data symbols based on the changes in amplitude and phase. For OFDM signals, the hub first recovers each subcarrier signal through frequency domain decomposition, and then demodulates each subcarrier signal separately, and finally restores the data symbols.After demodulating the bit stream, the PLC hub extracts the boundaries of the data frame, where each data frame usually contains fields such as source address, destination address, data content, and check code. The PLC hub parses the source address and destination address fields in the data frame to determine the sender (lighting fixture) and receiver (PLC hub) of the frame data. The PLC hub performs an integrity check on each received data frame through a check code (such as CRC check). If an error is found, the PLC hub requests to resend the data frame; if the check passes, the data content of the data frame continues to be processed. Furthermore, in the demodulated and checked data frame, the data content contains the original various parameter data (temperature, humidity, etc.). At this time, the PLC hub can extract each parameter data and perform further processing or forwarding. It should be pointed out that when a parameter data is divided into multiple data frames for transmission, the PLC hub will reassemble these frame data in sequence and restore them to the complete original data. Furthermore, the PLC hub temporarily stores the restored original parameter data in a cache area, ready for transmission to the LPWAN (Low Power Wide Area Network) gateway.

[0084] Among them, in the embodiment of the present invention, referring to the above two implementation methods of encoding and modulating the collected various parameter data and then loading them onto the power line for transmission, the PLC hub receives the modulated signals sent by multiple lighting fixtures from the connected power line, demodulates and restores the original various parameter data, and also has two corresponding implementation methods, wherein in the first implementation method, the steps specifically include:

[0085] The PLC hub receives modulated signals in different time slots or frequency bands from the connected power line, determines the identity of the corresponding lighting fixture according to the time slot or frequency band to which each modulated signal belongs, and demodulates various parameter data of each lighting fixture.

[0086] Specifically, the PLC hub receives all modulated signals from the power line through a power line coupler. Since the signals come from different lighting fixtures, the PLC hub needs to distinguish signals in different time slots or different frequency bands. If the above-mentioned time division multiple access (TDMA) mechanism is adopted, the PLC hub determines the source of the signal based on the arrival time (i.e., time slot) of the received data in the power line. Since each lighting fixture sends data in a specific time slot, the PLC hub can determine the source lighting fixture of the data by identifying the time slot. If the frequency division multiple access (FDMA) mechanism is adopted, the PLC hub distinguishes the identity of the lighting fixture based on the frequency component of the signal. Since the signal of each lighting fixture occupies a different frequency band, the PLC hub can identify the source of the data by analyzing the frequency of the signal. The PLC hub dynamically adjusts the demodulation parameters according to the received modulated signal and the channel status, and demodulates the original digital signal. At this time, the demodulated digital signal also needs to be decoded to convert the above-mentioned encoded data into the original data frame. The PLC hub verifies the integrity of the data through the check code (such as CRC) in the data frame to determine whether the data is wrong during the transmission process. At this time, after the check, the PLC hub restores the original parameter data of the lighting fixture. It should be pointed out that the PLC hub not only demodulates the actual parameter data in the data frame, but also extracts the identity information of the sending lighting fixture from the source address field in the data frame. Therefore, by distinguishing the time slot or frequency band, the PLC hub can accurately match the data with the corresponding lighting fixture. Even if there is no clear identity field in the data, the PLC hub can also identify the identity of the lighting fixture based on the sending time slot or frequency band.

[0087] In the second implementation, the steps specifically include:

[0088] The PLC hub receives the modulated signal sent by the lighting fixture from the connected power line and demodulates it into the parameter data of the original digital signal;

[0089] The PLC hub decodes the digital data into data frames, identifies the source address, destination address, data content and checksum based on the data frames, and matches them based on the destination address;

[0090] If the match is successful, the identity of the corresponding lighting fixture is determined according to the source address and various parameter data of the lighting fixture is determined according to the data content.

[0091] Specifically, the PLC hub receives the modulated signal from the power line through the power line coupler, and restores the received modulated signal to the parameter data of the original digital signal (i.e., digital bit stream) through the above demodulation method. After obtaining the parameter data of the original digital signal, the PLC hub needs to find the starting position of the data frame, which is achieved through the frame synchronization mechanism. The PLC hub identifies the boundary of the data frame through the special mark in the frame header. At this time, the PLC hub restores the bit stream to specific information, including the source address, the target address, the data content and the check code, by reading and parsing each field of the data frame. Then the PLC hub determines whether the data frame is sent to itself by parsing the target address in the data frame. If the target address matches the address of the PLC hub, the data frame is processed. If the target address does not match, the PLC hub discards the data frame or ignores its content. Among them, each lighting fixture is distributed in each area in the special environment such as the mine and tunnel where it is used. At this time, the lighting fixtures in different positions may be distributed in a larger area, so it is impossible for all lighting fixtures to be connected to the same PLC hub. In order to achieve efficient data transmission, lighting fixtures are usually divided into multiple areas according to the geographical location and the layout of power lines, and each area has a corresponding PLC hub. At this time, the lighting fixtures in each area transmit data to their corresponding PLC hubs through the power lines. In other words, each lighting fixture only needs to transmit data to the nearest PLC hub on the power line in its area, without the need for cross-regional transmission. It should be pointed out that the distribution and number of PLC hubs depend on the scale of special environments such as mines and tunnels and the topological structure of power lines, which are not specifically limited here. It should also be pointed out that each PLC hub is connected to the corresponding LPWAN gateway respectively, so by parsing the digital source address and destination address in the data frame, the PLC hub can determine whether the data frame is sent to itself by parsing the destination address in the data frame, and identify the corresponding lighting fixture by parsing the source address in the data frame. At this time, the PLC hub performs an integrity check on the data in the frame by reading the check code (such as CRC check code) in the data frame. The check code is generated by the sender and is used to detect whether an error occurs during data transmission. If the check passes, it indicates that the data transmission is successful, and the PLC hub will continue to process the data content. If the check fails, the PLC hub requests to resend the data frame, or directly discards the frame. After the decoding is completed, the PLC hub extracts the various parameter data collected by the lighting fixture from the data content field in the data frame. It should be pointed out that if a data is divided into multiple data frames for transmission, the PLC hub will also reorganize these frames to restore the complete original data. Furthermore, the PLC hub temporarily stores the decoded data frame in the internal cache for further processing or data recording according to the protocol requirements.At this time, the PLC hub searches for the identity of the corresponding lighting fixture based on the parsed source address in order to associate the data with the specific device.

[0092] Step S30, the LPWAN gateway re-encodes and packages the various parameter data received from the PLC hub, and transmits the packaged data to the monitoring center via the LPWAN network;

[0093] In one embodiment of the present invention, the LPWAN gateway receives the demodulated and restored original parameter data from the PLC hub through a wired or wireless interface. The PLC hub transmits the data to the LPWAN gateway in a standard format according to its protocol. It is usually completed through a local area network (LAN), a serial port (UART), Ethernet, or other standard communication interfaces. Since the PLC network and the LPWAN network use different communication protocols, the LPWAN gateway needs to convert the data received from the PLC hub into a data format that complies with the LPWAN protocol. The LPWAN protocol usually has the characteristics of low power consumption, low bandwidth and high delay tolerance, so the gateway needs to adjust the data format according to the requirements of the LPWAN protocol. In order to adapt to the bandwidth limitations of the LPWAN, the LPWAN gateway may compress the received parameter data. For example, using efficient data encoding technology (such as differential encoding, RLE compression, etc.) to reduce the amount of data, thereby reducing the transmission burden without losing data accuracy. The LPWAN gateway packages the parameter data received from the PLC hub according to the requirements of the LPWAN protocol. Depending on the specific protocol of LPWAN (such as LoRa, NB-IoT, Sigfox, etc.), the size and format of the data packet will vary. In order to adapt to the limitations of the LPWAN network, the data usually needs to be split into smaller data frames for transmission. The LPWAN gateway will be responsible for segmenting, packaging and adding necessary control information to the data frame according to the protocol standard. The LPWAN gateway modulates the packaged data through the LPWAN wireless communication module (such as the LoRa module or the NB-IoT module) and transmits it through the LPWAN network. Different LPWAN technologies differ in data transmission. LoRa uses spread spectrum technology to transmit data over ultra-long distances and at low rates. The LoRa module sends the packaged data to the base station through a wireless channel. NB-IoT is based on cellular network technology and sends data to cellular base stations through narrowband spectrum. Sigfox uses ultra-narrowband communication to transmit small amounts of data to the Sigfox base station over ultra-long distances. The LPWAN gateway selects the current appropriate frequency band or communication time slot for data transmission according to the channel selection strategy of the LPWAN protocol to avoid interference and data conflicts. Among them, LPWAN technologies such as LoRa or NB-IoT can support long-distance transmission and are suitable for the complex environment in the mine. Since LPWAN has lower power consumption and longer transmission distance, the PLC hub can directly transmit data to the monitoring center without relying on multiple relay nodes.

[0094] Further, in one embodiment of the present invention, the step of transmitting the packaged data to the monitoring center through the LPWAN network includes:

[0095] The LPWAN gateway dynamically adjusts the transmission power and rate of the packaged data transmitted to the monitoring center based on the real-time monitoring of the transmission conditions of the LPWAN network;

[0096] The LPWAN gateway dynamically adjusts the size of the sub-packets into which the packaged data is divided based on real-time monitoring of the network load and signal strength of the LPWAN network.

[0097] Specifically, when the LPWAN gateway is transmitting data, it will monitor the current transmission conditions in real time, including parameters such as channel status, signal strength (such as received signal strength indicator RSSI), signal-to-noise ratio (SNR), and packet loss rate. Among them, in LPWAN protocols, such as LoRa and NB-IoT, the uplink feedback mechanism is supported, and the LPWAN gateway can evaluate the transmission performance based on the feedback information received from the base station. For example, if the LPWAN base station detects that the received signal is weak or the bit error rate is high, the base station will feedback the information to the LPWAN gateway. Furthermore, the LPWAN gateway dynamically adjusts the transmission power according to the changes in signal strength or signal-to-noise ratio. Normally, when the signal strength is weak, the LPWAN gateway will increase the transmission power to ensure that the data can successfully reach the base station; when the signal is strong, the LPWAN gateway can reduce the transmission power to save energy. Specifically, when the gateway detects a lower RSSI or SNR, it automatically increases the transmission power. When the signal strength is detected to return to a stable level, the transmission power can be gradually reduced to ensure optimal power output. Furthermore, the LPWAN gateway monitors the channel's SNR and RSSI parameters in real time. When the channel is in good condition, it selects a higher rate for transmission, such as a higher modulation method (such as SF7 in LoRa). If it detects an increase in network load, channel congestion, or signal attenuation, the rate will be reduced accordingly, and a lower transmission rate (such as SF12 in LoRa) will be selected to ensure transmission stability and data integrity.

[0098] Furthermore, the LPWAN gateway can monitor the load of the network based on the feedback information of the network. When the feedback information sent back by the LPWAN base station indicates that the current network load is large, the LPWAN gateway reduces the size of the transmission data packet to reduce network congestion; conversely, when the network load is small, the gateway can use larger data packets for transmission to improve transmission efficiency. When the network signal strength is strong, the LPWAN gateway can use larger data packets for transmission, because the bit error rate is low and the reliability of transmitting large packets is high; when the signal is weak, the LPWAN gateway will split the data packet into smaller sub-packets to reduce the risk of transmission failure and avoid more network resource waste caused by retransmission. Therefore, the LPWAN gateway adjusts the data packet splitting method according to the current signal strength (such as RSSI) or network load (such as packet loss rate). If it is detected that the network load is high or the signal is weak, the LPWAN gateway divides the smaller sub-packets and sends them one by one; when the network load is light or the signal is good, the LPWAN gateway packages the data frames into larger data packets to improve efficiency. Therefore, in the embodiment of the present invention, when the signal strength is high and the packet loss rate is low, the LPWAN gateway selects a larger data packet for transmission, so that the number of frames for data transmission can be reduced and the overhead can be reduced. When the network load is high or the signal quality deteriorates, the LPWAN gateway divides the data into multiple small sub-packets (sub-frames), thereby reducing the amount of data in each transmission and reducing the probability of transmission failure. At the same time, if a sub-packet fails to be successfully transmitted, the LPWAN gateway can perform selective retransmission according to the LPWAN protocol (such as the confirmation mechanism in LoRa), and only retransmit the lost sub-packet to improve transmission efficiency.

[0099] Step S40, the monitoring center receives the packaged data transmitted through the LPWAN network, demodulates and restores the data into various parameter data of the lighting fixture, and monitors and analyzes the various parameter data of the lighting fixture;

[0100] Among them, in one embodiment of the present invention, a data receiving module is provided in the server or platform of the monitoring center, which monitors the packaged data from the LPWAN network. After the packaged data arrives at the monitoring center, the data packet is first converted from a low-level signal to a form that can be processed by a high-level application through a demodulation module. Since the LPWAN network generally uses a low-power, long-distance modulation method (such as LoRa uses CSS modulation, and NB-IoT uses OFDMA), the monitoring center needs to demodulate these data packets to restore the original digital data. The demodulation process involves converting the received signal into digital information according to its characteristics (such as frequency, phase, amplitude), which corresponds to the modulation process at the transmitting end.

[0101] Furthermore, the demodulated data is encoded digital data, and the monitoring center decodes the data packet through a decoding module. The purpose of decoding is to restore the data to the original parameter value collected by the sensor. Commonly used encoding methods include FEC (forward error correction code), CRC (cyclic redundancy check code), etc. The monitoring center verifies the integrity of the data packet based on the check information (such as CRC check code) in the data packet to ensure that the data is not damaged or lost during transmission. The packaged data is usually a data frame composed of multiple fields, such as source address, destination address, data content, timestamp, check code, etc. The decoded data frame will be parsed according to the protocol standard to extract the relevant lighting fixture parameter data. The source address and destination address are used to identify the identity of the lighting fixture and the destination of the data. The monitoring center will associate the data with the corresponding lighting device through the address information. The data content contains various parameter data collected by the lighting fixture, such as temperature, humidity, brightness, working current, etc. The monitoring center will parse these data contents one by one for subsequent processing. Further, the decoded and parsed parameter data will be stored in a database or data warehouse. The parameter data of each lighting fixture will be stored together with its device ID, timestamp and other metadata to facilitate subsequent query, analysis and tracking of historical data.

[0102] Furthermore, in one embodiment of the present invention, after the step of monitoring and analyzing various parameter data of the lighting fixture, the following steps are further included:

[0103] The monitoring center determines whether the various parameter data of the lighting fixture exceeds the corresponding preset threshold value;

[0104] If so, the monitoring center determines whether to generate an alarm message to issue an alarm or generate a control instruction to control the lighting fixture according to the type of parameter data that exceeds the preset threshold.

[0105] Specifically, the monitoring center can use parameter data to perform status analysis, including the working status of the lamp, environmental conditions (temperature and humidity), power consumption, etc. These data can be used to determine whether the lamp is working properly and whether it needs maintenance or replacement. At the same time, the monitoring center compares the various parameter data of the lighting fixture with the corresponding preset thresholds, so that abnormal conditions can be identified. Specifically, when the type of parameter data exceeding the preset threshold is environmental parameter data, an alarm message is generated to alarm; and when the type of parameter data exceeding the preset threshold is working parameter data, a control instruction is generated to control the lighting fixture. For example, when the temperature of the environment in which a lighting fixture is located is higher than the set temperature threshold, the monitoring center determines the abnormal situation through analysis and automatically generates an alarm message, and the alarm notifies relevant personnel (such as maintenance personnel or administrators) for timely processing. The alarm information may include the name of the parameter that exceeds the threshold, the current value and the set threshold, the time of occurrence, the possible impact and the recommended measures. When the voltage or current of the lighting fixture is higher than the set voltage threshold or current threshold, the monitoring center determines the abnormal situation through analysis and generates a control instruction (such as lowering the brightness of the lamp or turning off the lamp) to control the lighting fixture.

[0106] Furthermore, in one embodiment of the present invention, after the step of monitoring and analyzing various parameter data of the lighting fixture, the following steps are further included:

[0107] The monitoring center sends the control instructions for controlling the target lighting fixtures to the LPWAN gateway through the LPWAN network;

[0108] The LPWAN gateway receives the control instructions transmitted by the monitoring center, decodes them and transmits them to the PLC hub;

[0109] The PLC hub receives the control instructions transmitted by the LPWAN gateway, packages, encodes and modulates the control instructions, and then loads them onto the power line for transmission;

[0110] The target lighting fixture receives the modulated signal sent by the PLC hub from the power line, demodulates and restores it to the original control instruction, and performs corresponding work control according to the control instruction.

[0111] Specifically, referring to the above, when the PLC hub packages, encodes and modulates the control instructions and then loads them onto the power line for transmission, there are two implementation methods. One implementation method is to load them onto the power line for transmission at a specific time slot or a specific frequency band corresponding to the target lighting fixture. At this time, the target lighting fixture receives the modulated signal sent by the PLC hub from the power line at the specific time slot or the specific frequency band, demodulates and restores it to the original control instruction, and performs corresponding work control according to the control instruction. Another implementation method is to package, encode and modulate the control instructions and then load them onto the power line for transmission, and package them into a data frame consisting of a source address, a target address, data content and a check code. At this time, when the target lighting fixture receives the modulated signal sent by the PLC hub from the power line, it can be demodulated and restored to the original control instruction according to the corresponding determination of the data frame, and perform corresponding work control according to the control instruction.

[0112] In summary, the existing wireless communication methods have limited signal coverage in underground and long-distance environments and are easily restricted by the physical environment. The embodiments of the present invention use PLC technology to achieve reliable data transmission locally, and at the same time expand the coverage through LPWAN, solving the problem of areas that are difficult to cover with the existing technology. At the same time, the electromagnetic interference in special environments such as mines and tunnels is relatively complex, and traditional wireless communication methods are difficult to work stably. The embodiments of the present invention use power line transmission to avoid signal attenuation caused by electromagnetic interference and improve the stability of data transmission. At the same time, the communication methods of the existing technology often face high delays and data packet loss rates in large-scale deployments, while the embodiments of the present invention use PLC to achieve efficient transmission locally, and use LPWAN to ensure the quality of long-distance data transmission, reducing transmission delays and packet loss problems. At the same time, the embodiments of the present invention use the monitoring center to demodulate and analyze the data transmitted by the LPWAN network in real time, and can monitor and manage each lighting fixture in real time, meet the remote monitoring and intelligent scheduling requirements of the working status of lighting fixtures in environments such as mines, and improve management efficiency and safety.

[0113] In summary, the lighting fixture data transmission method in the above-mentioned embodiment of the present invention uses PLC technology to transmit data through power lines through lighting fixtures, which can avoid signal interference and shielding problems that may be faced by traditional wireless communication methods in complex electromagnetic environments, and is particularly suitable for environments with high humidity, high dust and complex electromagnetic interference such as mines and tunnels; and uses the LPWAN network to transmit data to the monitoring center through the LPWAN gateway. Since LPWAN has the characteristics of long distance, wide coverage, and low power consumption, stable data transmission can be achieved in a large range; since PLC technology has the advantages of high data transmission rate and low latency within a short distance, data aggregation of local lighting equipment is performed through power lines, which reduces signal attenuation and packet loss problems, and LPWAN technology expands the coverage range, ensures the stability of data transmission in long-distance environments, and solves the problem of poor stability of data transmission signals of existing lighting fixtures in special environments with inconvenient communication.

[0114] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0115] The above-described embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the attached claims.

Claims

1. A lighting fixture data transmission method, characterized in that: The method comprises: The lighting fixture continuously collects various parameter data of the environment and working state, and encodes and modulates the collected parameter data and loads them onto the power line for transmission; The PLC hub receives modulated signals sent by multiple lighting fixtures from the connected power lines, demodulates and restores them into original parameter data, and forwards the parameter data to the connected LPWAN gateway; The LPWAN gateway re-encodes and packages the various parameter data received from the PLC hub and transmits the packaged data to the monitoring center via the LPWAN network; The monitoring center receives the packaged data transmitted through the LPWAN network, demodulates and restores it into various parameter data of the lighting fixtures, and monitors and analyzes the various parameter data of the lighting fixtures.

2. The lighting fixture data transmission method according to claim 1, characterized in that: The step of encoding and modulating the collected various parameter data and then loading them onto the power line for transmission comprises: The lighting fixture converts, packages and encodes the collected parameter data into digital data; The lighting fixtures monitor the channel status on the power line in real time and dynamically adjust the modulation parameters according to the channel status; The lighting fixture modulates the encoded digital data into a modulation signal transmitted on the power line according to the adjusted modulation parameters; The lighting fixture superimposes the modulated signal on the current of the power line for transmission.

3. The lighting fixture data transmission method according to claim 2, characterized in that: The steps of receiving the modulated signals sent by the plurality of lighting fixtures from the connected power lines by the PLC hub, demodulating and restoring the signals into the original various parameter data include: The PLC hub receives modulation signals sent by a plurality of lighting fixtures from the connected power line, and identifies the modulation mode used by the modulation signal according to the signal characteristics of the modulation signal, wherein the signal characteristics include phase, frequency and amplitude; The PLC hub monitors the channel status on the power line in real time and adjusts the demodulation parameters according to the dynamic changes of the channel status; The PLC hub demodulates the modulated signal and restores it to the original parameter data according to the demodulation method corresponding to the modulation method and the adjusted demodulation parameters.

4. The lighting fixture data transmission method according to claim 1, characterized in that: The step of transmitting the packaged data to the monitoring center via the LPWAN network includes: The LPWAN gateway dynamically adjusts the transmission power and rate of the packaged data transmitted to the monitoring center based on the real-time monitoring of the transmission conditions of the LPWAN network; The LPWAN gateway dynamically adjusts the size of the sub-packets into which the packaged data is divided based on real-time monitoring of the network load and signal strength of the LPWAN network.

5. The lighting fixture data transmission method according to claim 1, characterized in that: The step of encoding and modulating the collected various parameter data and then loading them onto the power line for transmission comprises: The lighting fixture encodes and modulates the collected parameter data and then loads it onto the power line for transmission in the allocated specific time slot or specific frequency band; The steps of receiving the modulated signals sent by the plurality of lighting fixtures from the connected power lines by the PLC hub, demodulating and restoring the signals into the original various parameter data include: The PLC hub receives modulated signals in different time slots or frequency bands from the connected power line, determines the identity of the corresponding lighting fixture according to the time slot or frequency band to which each modulated signal belongs, and demodulates various parameter data of each lighting fixture.

6. The lighting fixture data transmission method according to claim 2, characterized in that: The steps of converting, packaging and encoding the collected parameter data into digital data by the lighting fixture include: The lighting fixture converts the collected parameter data into parameter data of digital signals; The lighting fixture packages the parameter data of the digital signal into a data frame, wherein the data frame includes a source address, a target address, data content and a check code; The lighting fixture encodes the data frame into digital data.

7. The lighting fixture data transmission method according to claim 6, characterized in that: The step of the lighting fixture superimposing the modulated signal on the current of the power line for transmission includes: The lighting fixture listens to the power line to see if there are other lighting fixtures transmitting data; If yes, then continue to listen to whether there are other lighting fixtures transmitting data on the power line after waiting for a random time, until there are no other lighting fixtures transmitting data on the power line; If not, the modulated signal is superimposed on the current of the power line for transmission.

8. The lighting fixture data transmission method according to claim 7, characterized in that: The steps of receiving the modulated signals sent by the plurality of lighting fixtures from the connected power lines by the PLC hub, demodulating and restoring the signals into the original various parameter data include: The PLC hub receives the modulated signal sent by the lighting fixture from the connected power line and demodulates it into the parameter data of the original digital signal; The PLC hub decodes the digital data into data frames, identifies the source address, destination address, data content and checksum based on the data frames, and matches them based on the destination address; If the match is successful, the identity of the corresponding lighting fixture is determined according to the source address and various parameter data of the lighting fixture is determined according to the data content.

9. The lighting fixture data transmission method according to claim 8, characterized in that: The step of monitoring and analyzing various parameter data of the lighting fixture further includes: The monitoring center sends the control instructions for controlling the target lighting fixtures to the LPWAN gateway through the LPWAN network; The LPWAN gateway receives the control instructions transmitted by the monitoring center, decodes them and transmits them to the PLC hub; The PLC hub receives the control instructions transmitted by the LPWAN gateway, packages, encodes and modulates the control instructions, and then loads them onto the power line for transmission; The target lighting fixture receives the modulated signal sent by the PLC hub from the power line, demodulates and restores it to the original control instruction, and performs corresponding work control according to the control instruction.

10. The lighting fixture data transmission method according to claim 1, characterized in that: The step of monitoring and analyzing various parameter data of the lighting fixture further includes: The monitoring center determines whether the various parameter data of the lighting fixture exceeds the corresponding preset threshold value; If so, the monitoring center determines whether to generate an alarm message to issue an alarm or generate a control instruction to control the lighting fixture according to the type of parameter data that exceeds the preset threshold.

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