Plant growth data monitoring interaction method based on user-defined communication protocol

Abstract

The invention discloses a plant growth data monitoring interaction method based on a user-defined communication protocol, and relates to the field of digital information transmission, a communication superframe corresponding to an environment change period is defined, and a convergence gateway broadcasts a synchronous beacon frame containing a superframe serial number; the monitoring node receives the synchronous beacon frame, calculates a target logic time slot by using a discrete mapping algorithm based on the unique hardware identifier and the superframe serial number, and awakens and sends data in the target logic time slot; and if the synchronous beacon frame is not received, the monitoring node performs reverse deduction on the captured neighbor node identifier by using a discrete mapping algorithm so as to reconstruct the whole network time base, and the problem of channel congestion caused by large-scale node synchronous concurrent transmission is solved under the condition of not depending on complex signaling scheduling.

Description

A Plant Growth Data Monitoring and Interaction Method Based on a Custom Communication Protocol Technical Field

[0001] This invention relates to a plant growth data monitoring and interaction method based on a custom communication protocol, belonging to the field of digital information transmission technology. Background Technology

[0002] Current media access control layer protocols for massive sensor nodes generally adopt contention-based random access mechanisms. Mainstream communication protocols are based on ALOHA or carrier sense multiple access collision avoidance algorithms. The core design premise assumes that the reporting behavior of each node in the network follows a Poisson distribution in time, and that the data generation of each node is independent and exhibits discrete random characteristics on the time axis. In typical scenarios with moderate node size and sparse traffic, this unlicensed frequency band random contention mechanism achieves plug-and-play and flexible network expansion with extremely low protocol overhead. However, when communication technology is applied to specific monitoring scenarios driven by strong external periodic environmental factors, the assumption of independent and identically distributed traffic no longer holds. In intensive agricultural production or precise environmental monitoring applications, massive deployment of sensor nodes is controlled by consistent ambient light cycles or temperature control commands. When the external environmental state undergoes a step change, massive nodes in the area simultaneously trigger attempts to preempt the channel to report data, causing the network traffic model to change from a discrete random distribution to highly time-correlated synchronous concurrent pulses. Under this traffic model, existing random access protocols face the risk of fundamental failure.

[0003] For example, Chinese invention patent CN115443890B discloses a smart irrigation management system for garden landscapes. Although it achieves intelligent perception of plant growth status and water and fertilizer decision-making through CCD image acquisition and multi-dimensional environmental sensors, the data transmission link design relies solely on the passive transmission of conventional wireless data transmission units. In the face of thousands of nodes being synchronously awakened by ambient light or unified commands in intensive agriculture, the lack of time-domain discreteness and frequency jump planning at the physical channel level makes it prone to congestion and loss of key monitoring data due to sudden channel competition avalanches. The host computer cannot complete the complete mapping of the entire network data within the effective control cycle and cannot support high-time-efficiency closed-loop control.

[0004] Therefore, the technical problem to be solved by this invention is how to transform highly synchronous concurrent traffic into deterministic discrete time-frequency transmission sequences through the underlying logic mapping mechanism of the protocol, thereby solving the channel collision and congestion problem and maximizing the utilization of spectrum resources. Summary of the Invention

[0005] To address the problems mentioned in the background art, the technical solution of this invention is as follows: A plant growth data monitoring and interaction method based on a custom communication protocol, applied to a star network including a convergence gateway and multiple monitoring nodes, the method comprising:

[0006] Define a communication superframe whose duration corresponds to the environmental change cycle of the monitored object, and divide the communication superframe into multiple logical time slots in the time domain; the aggregation gateway periodically broadcasts a synchronization beacon frame containing the current superframe sequence number;

[0007] The monitoring node receives the synchronization beacon frame, extracts the superframe sequence number, and uses the monitoring node's unique hardware identifier and the superframe sequence number as common input variables to execute a preset discrete mapping algorithm to calculate the target logical time slot of the monitoring node within the current communication superframe. The monitoring node enters a sleep state and wakes up when the local timer reaches the start of the target logical time slot, and sends a monitoring data frame to the aggregation gateway.

[0008] When a monitoring node does not receive a synchronization beacon frame within a preset time period, it performs emergency parasitic synchronization steps: it starts listening mode to capture any monitoring data frames sent by neighboring nodes; and it parses the hardware identifiers of neighboring nodes.

[0009] By using a discrete mapping algorithm and substituting the hardware identifiers of neighboring nodes, the theoretical logical time slot in which the neighboring node is located within the current communication superframe is deduced in reverse; the time difference between the actual arrival time of the monitored data frame and the theoretical logical time slot is calculated.

[0010] It also reconstructs the start timestamp of the current communication superframe based on the time difference, and calibrates the local clock of the monitoring node according to the reconstructed start timestamp, thereby maintaining phase synchronization with the star network in the case of loss of synchronization beacon frames.

[0011] Preferably, the method further includes a frequency mapping step: dividing the available wireless communication spectrum into multiple logical channels; the monitoring node executes a preset channel hopping algorithm to calculate the target logical channel index based on a specific bit segment of a unique hardware identifier and a superframe sequence number; at the start of the arrival of the target logical time slot, the monitoring node tunes its wireless radio frequency unit to the center frequency corresponding to the target logical channel index to send monitoring data frames; wherein, the channel hopping algorithm and the discrete mapping algorithm share the superframe sequence number as a dynamic perturbation factor, and the channel hopping algorithm and the discrete mapping algorithm are orthogonal in mapping logic, driving the monitoring node to traverse different logical channels in different communication superframes.

[0012] Preferably, the discrete mapping algorithm performs the following logical operations: ,in, The index of the target logical time slot, A numerical value that is a unique hardware identifier. For superframe sequence number, This represents the total number of logical time slots within a communication superframe. This indicates a bitwise XOR operation; the operation ensures that the bits are distinct. The nodes are in different The time slot collision relationships within the period exhibit a discrete distribution.

[0013] Preferably, the method further includes a chain-like differential silencing step based on temporal adjacency: within a preset listening window before reaching the target logical time slot, the monitoring node attempts to receive reference data frames sent by logical neighbor nodes assigned to the preceding logical time slot by the discrete mapping algorithm; if the reference data frame is successfully received, the difference between the local data to be sent and the payload data in the reference data frame is calculated; only when the difference is greater than a preset silencing threshold or no reference data frame is received within the listening window, the monitoring node performs the sending action of monitoring data frames within the target logical time slot.

[0014] Preferably, the method further includes a batch confirmation feedback step: the aggregation gateway maintains a receive status bitmap of the mapping logical time slot occupancy status during the reception process; when the aggregation gateway broadcasts the synchronization beacon frame of the next cycle, it encapsulates the compressed encoded data of the receive status bitmap in the payload of the synchronization beacon frame; after receiving the synchronization beacon frame, the monitoring node decompresses and indexes the compressed encoded data according to the target logical time slot index it occupies in the communication superframe to determine whether the transmission of the previous cycle was successful.

[0015] Preferably, the method further includes a clock drift compensation step: when receiving a monitoring data frame, the aggregation gateway measures the time deviation between its actual arrival time and its theoretical arrival time, and calculates the clock drift rate parameter of the corresponding monitoring node based on the time deviation of multiple consecutive cycles; the aggregation gateway encapsulates the clock drift rate parameter in a synchronization beacon frame and sends it to the monitoring node; when the monitoring node enters a sleep state, it uses the received clock drift rate parameter to perform feedforward correction on the counting frequency of the local timer, and automatically cancels the accumulated drift error of the local clock at the wake-up time.

[0016] Preferably, the method further includes interference sensing and avoidance steps: the aggregation gateway identifies theoretically idle time slots within the current communication superframe that are not mapped by any monitoring node, and performs channel noise power measurement during the theoretically idle time slots to construct an environmental interference distribution map; if the noise power of a specific time slot interval exceeds a preset threshold, the aggregation gateway marks the time slot interval as an unavailable interval in the synchronization beacon frame of the next cycle; after parsing the synchronization beacon frame, if the calculated target logical time slot falls into the unavailable interval, the monitoring node migrates the target logical time slot to the subsequent available time slot interval according to the preset offset rule.

[0017] Preferably, the communication superframe duration is set to 24 hours or an artificial light control cycle; the aggregation gateway updates the superframe sequence number and broadcasts a synchronization beacon frame according to the preset light control schedule or the trigger signal from the ambient light intensity sensor, driving all network monitoring nodes to synchronously execute the parameter update of the discrete mapping algorithm at the start of a new environmental cycle.

[0018] Preferably, the emergency parasitic synchronization steps include: when a monitoring node captures a monitoring data frame from a neighboring node, it measures the received signal strength indication value of that signal; only when the received signal strength indication value is greater than a preset reliable synchronization threshold is the reverse deduction and local clock calibration operation performed to prevent the amplification of timing errors caused by using weak signals from a remote end for synchronization.

[0019] Preferably, the clock drift rate parameter is a signed value used to indicate the number of microseconds per hour that the local crystal oscillator of the monitoring node deviates from the reference clock of the aggregation gateway. When the monitoring node performs feedforward correction, it divides the clock drift rate parameter by the total duration of the local sleep cycle to obtain the single compensation step value during the current sleep period, and applies the single compensation step value in the sleep timer interrupt service routine.

[0020] Compared with the prior art, the beneficial effects of the present invention are:

[0021] 1. The data monitoring and interaction method based on a custom communication protocol provided in this application solves the channel congestion problem caused by synchronous concurrent traffic generated by a large number of nodes under environmental triggering by establishing an implicit discrete mapping mechanism based on the unique hardware identifier of the node and the dynamic superframe sequence number. It uses the broadcast superframe sequence number as a time-varying disturbance factor to discretely distribute highly correlated burst transmission requests on the time axis throughout the entire communication cycle according to deterministic mathematical logic. The monitoring node does not need to wait for the gateway to issue specific time slot allocation instructions or maintain a huge dynamic routing table, realizing zero-conflict scheduling of physical layer access for massive nodes. Under the premise of eliminating signaling interaction overhead and avoiding carrier sense contention collisions, it ensures that the system throughput and access capacity expand linearly with the increase of the number of nodes.

[0022] 2. This invention utilizes the same superframe sequence number as the driving source and controls the selection of time-domain transmission slots and frequency-domain physical channels through orthogonal logic operations to construct a two-dimensional time-frequency discrete transition pattern. The monitoring node calculates the target time slot and target channel according to different segments of its own hardware identifier, enabling the node to automatically migrate to different physical frequencies for transmission in different superframe periods. The built-in frequency migration mechanism eliminates the need for additional handshake negotiation or spectrum scanning between the transmitting and receiving parties, forcing the node to periodically avoid standing wave fading or continuous interference at specific frequency points, reducing the data loss rate caused by the deterioration of fixed channel quality, and improving the spectrum utilization efficiency of a single gateway through hybrid multiplexing of time-frequency resources.

[0023] 3. This application constructs a parasitic clock recovery mechanism based on the reverse deduction of neighbor traffic. When the gateway synchronization beacon is lost, the monitoring node reconstructs the entire network time base by capturing uplink data frames of any neighbor node in the channel. The monitoring node uses a known global discrete mapping algorithm and the captured neighbor identifier to reverse calculate the theoretical transmission time of the neighbor node. Based on this, the deviation between the current time and the theoretical time is calculated to correct the local clock. The background traffic in the network that originally existed as interference signals is transformed into distributed time synchronization resources. This ensures that nodes at the network edge or in areas with signal obstruction use implicit information in the environment to maintain phase synchronization with the main network, avoiding time slot misalignment and communication islanding effects caused by the accumulation of crystal oscillator drift due to long-term dormancy. Attached Figure Description

[0024] Figure 1 is a schematic diagram of the monitoring data interaction process that integrates discrete mapping and parasitic synchronization according to the present invention;

[0025] Figure 2 is a comparison of the channel avoidance mechanism and data delivery rate under dynamic interference environment of the present invention.

[0026] Figure 3 is a schematic diagram of the system technical architecture of the present invention based on time-frequency coordination and synchronous self-healing. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in further detail below. Obviously, the described embodiments are only some embodiments of this invention, not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0028] This invention provides a plant growth data monitoring and interaction method based on a custom communication protocol, applied to a star network architecture including a convergence gateway and multiple monitoring nodes. The convergence gateway serves as the network's time reference source and data aggregation point, while the monitoring nodes act as distributed environmental parameter acquisition units. The two interact via wireless radio frequency signals. A communication superframe structure, strictly mapped to the external environmental change cycle, is defined at the data link layer. The duration of the communication superframe is... To align with the biological rhythm cycle or artificial lighting control cycle of the monitored object, such as 24 hours or a specific lighting duration, the communication superframes are divided into a number of segments in the time domain. The logical time slots, among which The value is set to be greater than the total capacity of the monitoring nodes in the network, reserving sufficient mapping space, and the aggregation gateway periodically broadcasts a message containing the current superframe sequence number. and start timestamp The synchronization beacon frame, with a unique hardware identifier integrated within the monitoring node. Upon receiving a synchronization beacon frame, the system uses its locally integrated microcontroller to execute a pre-defined discrete mapping algorithm to assign hardware identifiers... The value and the superframe sequence number The common input variables are subjected to a bitwise XOR operation, and the result is then divided by the total number of logical time slots within the communication superframe. Perform a modulo operation to determine the unique transmission target logical time slot index of the monitoring node within the current superframe period. The discrete mapping algorithm satisfies the following relationship: ,in, The index of the target logical time slot, A unique hardware identifier for the monitoring node. The sequence number of the current superframe. This represents the total number of logical time slots. This represents the bitwise XOR operation, and this represents the modulo operation. It introduces a time-incrementing... As a dynamic disturbance factor, it ensures that even between two monitoring nodes... In the If a collision occurs after taking the modulus, its impact in the next superframe cycle will be... The changes are automatically mapped to different logical time slots, achieving deterministic discretization of physical layer access conflicts.

[0029] Building upon this, to further utilize spectrum resources and avoid deep fading at specific frequencies, the interactive method performs a frequency mapping step orthogonal to the time-domain mapping at the physical layer, dividing the available wireless communication spectrum into... Each logical channel, the monitoring node utilizes hardware identifiers Specific bit segments and superframe sequence numbers Execute the channel hopping algorithm to determine the target logical channel index. The channel hopping algorithm satisfies the following relationship: ,in, For the index of the target logical channel, This means shifting the hardware identifier right by 8 bits to extract the high-order byte. The total number of available logical channels is used by the monitoring node to count the number of channels in its local timer up to the target logical time slot. Wake up at the start time and tune the wireless radio frequency unit to the target logical channel index. The monitoring data frames are directly transmitted at the corresponding center frequency. To address the potential local clock drift issue that may occur during long-term operation of the monitoring nodes, this method integrates a clock drift compensation mechanism based on bidirectional parameter calibration. When the aggregation gateway receives a monitoring data frame, it uses its internal high-precision clock to measure the actual physical arrival time of the data frame. With theoretical arrival time Time deviation between Based on multiple consecutive superframe cycles The clock drift rate parameter of the monitoring node is calculated from the sample sequence. This parameter characterizes the frequency deviation of the local crystal oscillator relative to the gateway's reference clock, in microseconds per hour. The aggregation gateway will use the clock drift rate parameter. Encapsulated in a synchronization beacon frame and broadcast, the monitoring node utilizes the received signal when entering a sleep state. Feedforward correction is applied to the counting frequency of the local sleep timer during each sleep cycle. Within, compensation time will be automatically added or deducted. The calculation satisfies .

[0030] To improve network efficiency under high-density deployment, this method also includes a chain-like differential silencing mechanism based on temporal adjacency, which monitors nodes arriving at the target logical time slot. Within the previously preset listening window, attempts were made to receive data allocated to the preceding logic time slot by the discrete mapping algorithm. If the reference data frame sent by the logical neighbor node is successfully decoded, the difference between the local sensor value to be sent and the load value in the reference data frame is calculated. If the absolute value of the difference is greater than the preset silence threshold, the signal is silenced. The monitoring node only performs a sending action when the specified conditions are met; otherwise, it operates silently and stores the data locally to suppress spatially correlated redundant traffic. If the monitoring node does not receive a synchronization beacon frame within a preset time period, it executes an emergency parasitic synchronization step, initiating a listening mode to capture any monitoring data frames sent by neighboring nodes and parse the hardware identifier of that neighboring node. By using the discrete mapping algorithm, the theoretical logical time slot of the neighboring node within the current communication superframe can be deduced in reverse. Therefore, based on the actual capture time of the monitoring data frame Reverse reconstruction of the start timestamp of the current communication superframe The calculation satisfies ,in, The duration of a single logical time slot is used to calibrate the local clock to maintain phase synchronization with the network.

[0031] Example 1

[0032] In a greenhouse environment simulation verification scenario involving 5000 high-density deployed monitoring nodes, the channel access performance of this invention in handling strongly correlated synchronous concurrent traffic was examined. This scenario set the communication superframe length to 60 minutes and the total number of logical time slots to [missing information]. Set to 8000, single time slot duration With a time interval of 50 milliseconds, when the ambient light control system triggers the sunrise mode, 5000 monitoring nodes simultaneously generate reporting requests, which are broadcast to the aggregation gateway with serial numbers. After receiving the synchronization beacon frame, all monitoring nodes in the network use their own unique hardware identifiers. implement The discrete mapping operation forces the 5000 concurrent requests, which were originally highly overlapping on the time axis, to be discretely mapped into 8000 logical time slots according to a uniform probability distribution. This reduces the theoretical collision probability within a single time slot. For the very few nodes where hash results collide, in the next cycle when the superframe sequence number is updated... At that time, according to the operational logic Its target time slot will undergo a nonlinear jump, thereby automatically eliminating the continuous collision of the physical layer. Actual test data shows that within 24 consecutive superframe cycles, the network's packet delivery rate remains above 99.9%. Due to the elimination of carrier sense and random backoff processes, the average on-time of the radio transmitter unit is reduced by more than 95% compared to the traditional CSMA / CA protocol.

[0033] Example 2

[0034] To verify the transmission stability and energy efficiency of this invention under actual interference conditions, an experimental testbed consisting of one aggregation gateway and 1000 monitoring nodes was built. Wideband Gaussian white noise ranging from -100dBm to -85dBm was introduced as background interference. The experiment compared the standard ALOHA random access mode and the discrete mapping mode of this invention over a continuous 72-hour period. The experimental parameters were set as follows: superframe period... The duration is 1 hour, the data packet payload length is 32 bytes, and the number of logical channels is [number missing]. There are 8 monitoring nodes. In the discrete mapping mode of this invention, the monitoring nodes simultaneously perform time slot mapping and channel hopping. The key performance indicators recorded in the experiment are shown in the table below.

[0035] Table 1: Comparison of Performance Indicators between ALOHA Random Access and the Discrete Mapping Mode of the Invention

[0036]

[0037] Data shows that this invention improves the reliability and real-time performance of data transmission under the same interference conditions through implicit phase discretization and frequency hopping mechanisms, and significantly reduces the energy consumption of nodes.

[0038] Example 3

[0039] This embodiment, in conjunction with Figures 1 to 3, describes the plant growth data monitoring interaction method based on a custom communication protocol. As shown in Figure 1, the interaction process begins with the aggregation gateway sending a synchronization beacon frame containing a superframe sequence number and a receive status bitmap payload via wireless broadcast. The monitoring node determines whether it has received the synchronization beacon frame. If the reception is successful, the node performs discrete mapping and channel hopping steps, XORing the hardware identifier with the superframe sequence number. As input, the target logical time slot and target logical channel are generated. Combined with the clock drift compensation step of the local timer using the drift rate parameter feedforward correction to correct the timing, the node enters the chain differential silencing step, listens to the data of the preceding neighbor node and calculates whether the difference is greater than the silencing threshold. If the difference does not exceed the threshold, it is determined to be redundant, and the node remains silent or sleeps, stores the data and waits for the next cycle. If the difference is large, it is woken up and tuned to the target frequency to send monitoring data frames. If it is determined that no beacon is received, the node enters the emergency parasitic synchronization step to capture the monitoring data frames of the neighbor node, and then performs full network time base reconstruction. The time base is restored by reverse deducing the theoretical logical time slots of the neighbors and calibrating the local clock phase.

[0040] As shown in Figure 2, the horizontal axis represents logical channel numbers 1 to 8, the left vertical axis represents interference intensity in dBm, and the right vertical axis represents data packet delivery rate in %. The solid line in the figure depicts the distribution of environmental interference intensity, showing the noise peak present at channel 5. The dashed line indicates a sharp drop in delivery rate without avoidance mechanisms in this high-interference region, while the dotted line indicates a delivery rate with avoidance mechanisms that maintains a high level of stability across the entire spectrum. As shown in Figure 3, this highly reliable plant growth monitoring data interaction system adopts a fishbone-shaped technical architecture, supported by four core functional modules. The time-domain discrete mapping mechanism module includes the UID XOR algorithm. The communication superframe definition, frequency domain hopping and anti-interference module covers logical channel division, orthogonal hopping algorithm and environmental interference distribution map, synchronization maintenance and self-healing module integrates neighbor time slot inverse deduction, emergency parasitic synchronization and clock drift compensation, and flow control and energy saving module consists of receive status bitmap compression, batch confirmation feedback and chain differential silence. All modules work together to establish the overall system performance.

[0041] Example 4

[0042] This embodiment details the engineering implementation procedure of the clock drift compensation mechanism. During the system initialization phase, the clock drift rate parameter is set. The initial value is 0. During operation, the aggregation gateway measures the arrival time of each received data packet, based on a certain monitoring node. For example, if the time deviation measured by the gateway within 5 consecutive superframe cycles... The time intervals are +2ms, +2.1ms, +2.2ms, +2.3ms, and +2.4ms respectively, and the overframe period is 1 hour. Therefore, the drift calculation module inside the gateway calculates the node's drift rate as +0.1ms / h using a linear regression algorithm. This value is quantized and encoded before being sent with the next synchronization beacon frame. Upon receiving the parameter, it is written to the RTC compensation register of the local microcontroller. During the sleep timer, the microcontroller automatically deducts 1 microsecond from the timer count every 36 seconds, or 0.01 hours, to compensate for the physical drift of the hardware crystal oscillator at the software level. According to actual tests, after adopting this compensation mechanism, the wake-up time deviation of the monitoring node using a common 32.768kHz crystal oscillator after 24 hours of continuous sleep is controlled within ±2 milliseconds, which meets the protection requirements of the 50-millisecond logic time slot.

[0043] Example 5

[0044] This embodiment describes the specific execution flow of the interference sensing and avoidance mechanism. The aggregation gateway uses the unmapped idle time slots within the superframe as a spectrum detection window, assuming that the current time slot within the superframe... to In the theoretically idle state, the gateway turns on the receiver and measures the Received Signal Strength Indicator (RSSI) during this period. If the average noise floor during this period exceeds a preset threshold of -85 dBm, the gateway determines that there is continuous external interference in this time slot interval and adds it to the bitmap field of the synchronization beacon frame in the next cycle. to If the target time slot is marked as unavailable after the monitoring node parses the beacon frame, it will be considered unavailable. If the data falls within this unavailable range, the transmission time will be postponed to the next available time according to preset rules. ,in, For a fixed offset, such as 20 time slots, and for the chained differential silencing mechanism, a silencing threshold for temperature changes is set. It is 0.2 When the monitoring node detects that the temperature data of its predecessor neighbor node is 25.0... The locally collected data is 25.1. At that time, due to the difference of 0.1 If the value is less than the threshold, the node automatically cancels transmission; when the local data value is 25.3... At that time, due to the difference of 0.3 If the value exceeds the threshold, the node will send data normally. This mechanism reduces the total network data communication volume by about 65% under steady-state conditions with uniform ambient temperature distribution.

[0045] Example 6

[0046] The monitoring data frame consists of a physical layer preamble, a synchronization header (PHR), and a physical layer service data unit (PSDU). The synchronization header has a pre-set 16-bit superframe sequence number echo field. When a monitoring node assembles and sends a data frame, it stores the current superframe sequence number in its local register. When directly writing to fields and performing the emergency parasitic synchronization step, the monitoring node in listening mode demodulates the captured neighbor node's data frames and extracts them. The value is valid for the current period. Input discrete mapping algorithm to solve the parameter missing problem under the condition of lost aggregation gateway synchronization beacon frame; discrete mapping algorithm Operations are performed following bit-width alignment rules, and input variables... It is a 32-bit unsigned integer; It is a 32-bit unsigned integer that increments over time; Set to a constant of 8000, if Significant digits exceeded Bit width, perform bit-by-bit truncation operation, and get The lower 32 bits are involved in the operation. and If the bit widths are inconsistent, pad the higher bits of the shorter value with zeros to make it 32 bits, then perform a bitwise XOR operation. The result... The range of values ​​is constrained by The interval corresponds to the valid logical time slot index within the communication superframe; the chained differential silencing step introduces the Received Signal Strength Index (RSSI) gating mechanism to verify the consistency between logical and physical neighbors and monitor the preset spatial correlation threshold of the node's internal memory. like After successfully receiving the reference data frame from the preceding logical neighbor node within the listening window, the processor reads the actual received signal strength value from the wireless radio frequency front end. ,when When a logical neighbor node is determined to be a relevant node, the subsequent data difference calculation and silent judgment process is triggered. If the physical distance between the two is too far and the environmental data does not have a strong correlation, the processor skips the difference calculation step and forces the node to perform the data transmission action in the target logical time slot. The procedure establishes that the silent mechanism only takes effect between nodes whose physical and logical locations are highly overlapping.

[0047] The interference detection and avoidance steps are executed based on a hardware identifier two-level hash offset algorithm to determine the migration target time slot. When the monitoring node parses the synchronization beacon frame, it obtains the original target logical time slot. Falling into the marked unavailable region At that time, calculate the new target time slot after migration. : ,in, This is the gap index at the end of the unavailable interval. To preset a fixed protection interval constant For example, time slot 50, The calculation follows the pseudo-random jitter amount based on node characteristics. , For a maximum jitter window width of 128 time slots, the algorithm re-distributes the multiple monitoring nodes originally mapped to the disturbed interval after migration. Time-domain windows are used to avoid secondary channel congestion caused by collective linear migration. Clock drift compensation parameter quantization and underlying register operation procedures are implemented, and the aggregation gateway issues clock drift rate parameters. Defined as a signed integer, with the unit being nanoseconds (ns / s), such as This means the local clock gains 2 microseconds per second relative to the reference clock, and the monitoring node's sleep timer is determined by frequency. For example, a 32768Hz low-power crystal oscillator drive, single sleep target count value Before entering sleep mode, the microcontroller receives... Calculate the compensation count value : The microcontroller will correct the sleep count value. Write to the real-time clock (RTC) compare register, and the RTC counter reaches... The wake-up interrupt is triggered in time, and the procedure dynamically fine-tunes the wake-up time in each sleep cycle to avoid the accumulation of timing errors due to crystal oscillator frequency deviation.

[0048] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A plant growth data monitoring and interaction method based on a custom communication protocol, applied to a star network containing a convergence gateway and multiple monitoring nodes, characterized in that... The method includes: defining a communication superframe with a time length corresponding to the environmental change cycle of the monitored object, and dividing the communication superframe into multiple logical time slots in the time domain; the aggregation gateway periodically broadcasting a synchronization beacon frame containing the current superframe sequence number; the monitoring node receiving the synchronization beacon frame, extracting the superframe sequence number, and using the monitoring node's unique hardware identifier and the superframe sequence number as common input variables, executing a preset discrete mapping algorithm to calculate the target logical time slot of the monitoring node within the current communication superframe; the monitoring node entering a sleep state and waking up at the start of the target logical time slot when the local timer reaches the start of the target logical time slot, sending a monitoring data frame to the aggregation gateway; when the monitoring node is in the pre- If no synchronization beacon frame is received within a specified time period, the following emergency parasitic synchronization steps are executed: Activate the listening mode to capture any monitoring data frame sent by neighboring nodes; parse the hardware identifier of the neighboring node; use a discrete mapping algorithm and substitute the hardware identifier of the neighboring node to reverse-determine the theoretical logical time slot in which the neighboring node is located within the current communication superframe; calculate the time difference between the actual arrival time of the monitoring data frame and the theoretical logical time slot; and reconstruct the start timestamp of the current communication superframe based on the time difference, and calibrate the local clock of the monitoring node according to the reconstructed start timestamp, thereby maintaining phase synchronization with the star network even when synchronization beacon frames are lost.

2. The plant growth data monitoring and interaction method based on a custom communication protocol according to claim 1, characterized in that, The method also includes a frequency mapping step: dividing the available wireless communication spectrum into multiple logical channels; the monitoring node executes a preset channel hopping algorithm to calculate the target logical channel index based on a specific bit segment of a unique hardware identifier and a superframe sequence number; at the start of the arrival of the target logical time slot, the monitoring node tunes its radio frequency unit to the center frequency corresponding to the target logical channel index to send monitoring data frames; wherein, the channel hopping algorithm and the discrete mapping algorithm share the superframe sequence number as a dynamic perturbation factor, and the channel hopping algorithm and the discrete mapping algorithm are orthogonal in mapping logic, driving the monitoring node to traverse different logical channels in different communication superframes.

3. The plant growth data monitoring and interaction method based on a custom communication protocol according to claim 2, characterized in that, The discrete mapping algorithm performs the following logical operations: ,in, The index of the target logical time slot, A numerical value that is a unique hardware identifier. For superframe sequence number, This represents the total number of logical time slots within a communication superframe. This indicates a bitwise XOR operation; the operation ensures that the bits are distinct. The nodes are in different The time slot collision relationships within the period exhibit a discrete distribution.

4. The plant growth data monitoring and interaction method based on a custom communication protocol according to claim 1, characterized in that, The method also includes a chain-like differential silencing step based on temporal adjacency: within a preset listening window before reaching the target logical time slot, the monitoring node attempts to receive reference data frames sent by logical neighbor nodes assigned to the preceding logical time slot by the discrete mapping algorithm. If the reference data frame is successfully received, the difference between the local data to be sent and the payload data in the reference data frame is calculated. The monitoring node will only perform the sending action of the monitoring data frame in the target logical time slot if the difference is greater than the preset silence threshold or if the reference data frame is not received in the listening window.

5. The plant growth data monitoring and interaction method based on a custom communication protocol according to claim 1, characterized in that, The method also includes a batch confirmation feedback step: the aggregation gateway maintains a receive status bitmap of the mapping logic time slot occupancy status during the reception process; When the aggregation gateway broadcasts the synchronization beacon frame for the next cycle, it encapsulates the compressed coded data of the received status bitmap in the payload of the synchronization beacon frame. After receiving the synchronization beacon frame, the monitoring node decompresses the compressed coded data and performs an index lookup based on the target logical time slot index it occupies in the communication superframe to determine whether the transmission of the previous cycle was successful.

6. The plant growth data monitoring and interaction method based on a custom communication protocol according to claim 1, characterized in that, The method also includes a clock drift compensation step: when the aggregation gateway receives the monitoring data frame, it measures the time deviation between the actual arrival time and the theoretical arrival time, and calculates the clock drift rate parameter of the corresponding monitoring node based on the time deviation of multiple consecutive cycles. The aggregation gateway encapsulates the clock drift rate parameter in a synchronization beacon frame and sends it to the monitoring node. When the monitoring node enters sleep mode, it uses the received clock drift rate parameter to feedforward correct the counting frequency of the local timer and automatically cancels the accumulated drift error of the local clock when it wakes up.

7. The plant growth data monitoring and interaction method based on a custom communication protocol according to claim 1, characterized in that, The method also includes interference detection and avoidance steps: the aggregation gateway identifies theoretically idle time slots within the current communication superframe that are not mapped by any monitoring node, and performs channel noise power measurement during the theoretically idle time slots to construct an environmental interference distribution map; if the noise power of a specific time slot interval exceeds a preset threshold, the aggregation gateway marks the time slot interval as an unavailable interval in the synchronization beacon frame of the next cycle; after parsing the synchronization beacon frame, if the calculated target logical time slot falls into the unavailable interval, the monitoring node migrates the target logical time slot to the subsequent available time slot interval according to the preset offset rule.

8. The plant growth data monitoring and interaction method based on a custom communication protocol according to claim 1, characterized in that, The communication superframe duration is set to 24 hours or an artificial light control cycle; the aggregation gateway updates the superframe sequence number and broadcasts a synchronization beacon frame according to the preset light control schedule or the trigger signal from the ambient light intensity sensor, driving all network monitoring nodes to synchronously execute the parameter update of the discrete mapping algorithm at the start of a new environmental cycle.

9. The plant growth data monitoring and interaction method based on a custom communication protocol according to claim 1, characterized in that, The emergency parasitic synchronization steps include: when a monitoring node captures a monitoring data frame from a neighboring node, it measures the received signal strength indication value of that signal; only when the received signal strength indication value is greater than a preset reliable synchronization threshold is the reverse deduction and local clock calibration operation performed.

10. The plant growth data monitoring and interaction method based on a custom communication protocol according to claim 6, characterized in that, The clock drift rate parameter is a signed value used to indicate the number of microseconds per hour that the local crystal oscillator of the monitoring node deviates from the reference clock of the aggregation gateway. When the monitoring node performs feedforward correction, it divides the clock drift rate parameter by the total duration of the local sleep cycle to obtain the single compensation step value during the current sleep period, and applies the single compensation step value in the sleep timer interrupt service routine.

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