CN115276864A - DMB terminal state information receiving system based on LoRa technology - Google Patents
DMB terminal state information receiving system based on LoRa technology Download PDFInfo
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- H—ELECTRICITY
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- H04H—BROADCAST COMMUNICATION
- H04H60/00—Arrangements for broadcast applications with a direct linking to broadcast information or broadcast space-time; Broadcast-related systems
- H04H60/29—Arrangements for monitoring broadcast services or broadcast-related services
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- H—ELECTRICITY
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- H04H—BROADCAST COMMUNICATION
- H04H20/00—Arrangements for broadcast or for distribution combined with broadcast
- H04H20/65—Arrangements characterised by transmission systems for broadcast
- H04H20/71—Wireless systems
- H04H20/72—Wireless systems of terrestrial networks
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- H—ELECTRICITY
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- H04H40/18—Arrangements characterised by circuits or components specially adapted for receiving
- H04H40/27—Arrangements characterised by circuits or components specially adapted for receiving specially adapted for broadcast systems covered by groups H04H20/53 - H04H20/95
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Abstract
The invention relates to a DMB terminal state information receiving system based on an LoRa technology, and belongs to the technical field of wireless signals. Aiming at the problem that a DMB (Digital Multimedia Broadcasting) system can only finish the transmission of data information in a one-way mode and cannot feed back operation errors or broadcast information errors, a Digital Multimedia Broadcasting (Digital Multimedia Broadcasting) state detection system based on LoRa and a LoRa ad hoc network mode based on polling are provided. The node terminal and the gateway equipment are additionally provided with the LoRa radio frequency module, so that running information of the DMB terminal can be transmitted to the central control terminal, the terminal can feed back to a background in time when the terminal cannot work normally, and technical support is provided for DMB application.
Description
Technical Field
The invention belongs to the technical field of wireless signals, and relates to a DMB terminal state information receiving system based on an LoRa technology.
Background
Digital Multimedia Broadcasting (DMB) is a wireless information transmission technology developed and expanded on the basis of Digital Audio Broadcasting (DAB). According to the current pilot DMB technology, its six sets of high quality audio are shared 1kW power transmission close to the coverage of a set of FM broadcasts transmitted only 10 kW. It can be seen that DAB is hundreds of times more power efficient than FM. The significant improvement of power efficiency means not only energy saving but also significant reduction of DMB construction costs, which would be very advantageous for large-scale popularization and use of DMB in scenic spots.
The inside DMB broadcasting system who uses of scenic spot can only one-way transmission of completion data information at present, only can only come to DMB terminal transmission data information by staff's control center, but DMB terminal is the unable reverse accuse end transmission information towards, so in case broadcasting terminal operation error appears or report the information wrong, the staff also can in time know and take effectual measure maintenance or remedy, this just causes when taking place the crisis condition, the unable good information of receiving of DMB terminal in some region in the scenic spot, thereby just can not realize reporting the function, consequently research scenic spot DMB digital broadcasting terminal has and its important meaning.
Disclosure of Invention
In view of the above, an object of the present invention is to provide a DMB terminal status information receiving system based on the LoRa technique. A DMB terminal state information receiving system is built on the basis of Long Range Radio (LoRa), and information of terminal operation is transmitted to a central control terminal through the LoRa. The broadcast can be timely fed back to the background when the broadcast cannot work normally, and powerful technical support is provided for scenic spot information release and emergency management.
In order to achieve the purpose, the invention provides the following technical scheme:
a DMB terminal state information receiving system based on LoRa technology comprises a node terminal and a gateway;
the node terminal and the gateway are provided with a Digital Multimedia Broadcasting (DMB) terminal and a long-distance radio LoRa module which are connected in sequence;
the LoRa module is also in data connection with the MCU;
the MCU is also connected with the LED module, the upper computer and the key module respectively;
the DMB terminal transmits data into the LoRa module through the associated port, the LoRa module integrates data information into a digital signal, and partial data information is transmitted to the MCU in a wireless transmission mode;
the MCU collects the data information transmitted by the LoRa module, analyzes and processes the collected data information, and finally presents the analyzed information in a screen;
the LED module is used for representing different working states and data information transmission and receiving states;
the key module regulates and controls the transmission state of polling data;
the upper computer displays the analyzed data on a PC (personal computer) end of a worker;
the communication of the LoRa module comprises transparent transmission and directional transmission;
the directional transmission is as follows: the method comprises the steps that a gateway sends polling request data to nodes in sequence according to a certain sequence, and when the nodes receive the polling request data every time, the data are returned to the gateway through directional transmission; the polling of one node is expected to be completed within 1 s-2 s, and the data receiving of 30-60 nodes is completed within one minute;
in the information receiving system, the node is in a receiving state when idle, and when receiving data, the data is compared with appointed polling request data; if the signals are the same, adding the address and the channel of the gateway before a frame of complete data, and returning the address and the channel to the gateway through directional transmission; if the data is different from the polling request signal, the terminal is in a receiving state;
the gateway continuously sends polling request data, after the polling request data is sent for one time, whether the data returned by the slave is received or not is judged, if yes, the data is sent to a computer through a serial port, and the address of a polling node is +1, and polling of the next node is carried out; if the slave machine return data is not received after overtime, skipping the request and polling the next node;
the gateway comprises a gateway polling module, an LoRa module, an upper computer, an LoRa configuration module, a key module and an LED lamp module, wherein the LoRa configuration module configures LoRa parameters when being electrified, after the parameters are set, the gateway polling module controls the LoRa module to send polling request signals to each node terminal, and if data returned by the nodes are received, the data are uploaded to the upper computer through a serial port; the node terminal comprises a DMB terminal, an LoRa radio frequency module and an LoRa configuration module, wherein when the LoRa module receives a polling request signal sent by the gateway terminal, the DMB terminal is controlled to send data to the gateway.
Optionally, the built-in chip model of the LoRa module is SX1278;
the LoRa radio frequency module is a wireless signal transmission module of 01-LoRa-ATK, and the model of the built-in core chip is SX1278;
connecting the LoRa radio frequency module with the DMB terminal through a serial port; a power supply voltage VCC, a grounding point GND, a pin RXD for receiving data and a pin TXD for sending data of the DMB terminal are respectively connected with VCC, GND, TXD and RXD of the LoRa module; wherein TXD is cross-connected with RXD.
Optionally, the RXD is associated with a PB10 pin on the single chip microcomputer, and the TXB pin is directly associated with a PB11 on the single chip microcomputer; the PB10/11 is used for completing the bidirectional transmission of data information; the KEY pin is related to a PA4 pin on the single chip microcomputer, and the LED end is directly related to a PA15 pin on the single chip microcomputer.
Optionally, in the information receiving system, an array is defined, data in the array simulates data sent by a serial port of a DMB terminal, a channel identifier is added behind original data, and data sent by the node is distinguished in a gateway side.
The invention has the beneficial effects that:
the DMB broadcasting system applied in the current scenic spot can only finish the transmission of data information in one way, and only can control the central control terminal by a worker to transmit the data information to the DMB terminal, but the DMB terminal can not transmit the information to the central control terminal in the reverse direction, so once the broadcasting terminal is in error or the broadcast information is in error, the system applicability is greatly reduced, and therefore the research will build a DMB terminal state information receiving system on the basis of the LoRa technology, and the information of the terminal operation is transmitted to the central control terminal through the LoRa technology. The broadcast can be ensured to be fed back to the background in time when the broadcast cannot work normally, and powerful technical support is provided for scenic spot information release and emergency management.
Firstly, drawing a system block diagram, and realizing the construction of corresponding hardware equipment of a gateway end and a node end. And then, the application software is used for compiling the program, so that the realization of the function is completed by matching with hardware facilities, and simultaneously, the program compiling mode and the path of a gateway end and a terminal are also described, a directional signal transmission mode taking an LoRa module as a core is introduced, data information transmitted by LoRa modules of different terminals is collected in a channel changing mode, namely, loRa networking is carried out in a polling mode.
Meanwhile, the original PCB layout is optimized, and the LoRa module is added on the basis of the original receiver PCB layout, so that the remote monitoring function of the system is realized, and a worker can find problems in time. Meanwhile, the wiring is optimized, and extra parasitic capacitance and parasitic inductance are avoided. After the system construction work is completed, the system is strictly tested from two dimensions of signal connectivity and transmission distance between the modules, and finally the quality of the system is evaluated through the obtained structure.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the means of the instrumentalities and combinations particularly pointed out hereinafter.
Drawings
For a better understanding of the objects, aspects and advantages of the present invention, reference will now be made to the following detailed description taken in conjunction with the accompanying drawings in which:
FIG. 1 is a block diagram of a node termination system;
FIG. 2 is a block diagram of a gateway system;
FIG. 3 is a schematic diagram of a networking mode;
FIG. 4 is a node framework diagram;
FIG. 5 is a gateway framework diagram;
FIG. 6 is a unitary design;
FIG. 7 is a system device association;
FIG. 8 is a flowchart of the judgment reply procedure;
FIG. 9 is a program execution flow;
FIG. 10 is a program execution flow;
fig. 11 shows the relative positions of the gateway and the nodes.
Detailed Description
The following embodiments of the present invention are provided by way of specific examples, and other advantages and effects of the present invention will be readily apparent to those skilled in the art from the disclosure herein. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention. It should be noted that the drawings provided in the following embodiments are only for illustrating the basic idea of the present invention in a schematic way, and the features in the following embodiments and examples may be combined with each other without conflict.
Wherein the showings are for the purpose of illustrating the invention only and not for the purpose of limiting the same, and in which there is shown by way of illustration only and not in the drawings in which there is no intention to limit the invention thereto; to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product; it will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted.
The same or similar reference numerals in the drawings of the embodiments of the present invention correspond to the same or similar components; in the description of the present invention, it should be understood that if there is an orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "front", "rear", etc., based on the orientation or positional relationship shown in the drawings, it is only for convenience of description and simplification of description, but it is not an indication or suggestion that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes, and are not to be construed as limiting the present invention, and the specific meaning of the terms may be understood by those skilled in the art according to specific situations.
1. Design principle and thought of system
1.1. Design of system block diagram
1.1.1.DMB terminal system block diagram
The corresponding system block diagram of DMB system terminal is relatively simple and easy, and direct LoRa module and the terminal that will encapsulate in advance adopt serial port to associate alright realize corresponding function, and the terminal can be through associating the port with data transmission to in the LoRa module, and then the LoRa module will be integrated data information into digital signal, transmits this part of data information to the gateway end through the mode of wireless transmission, as shown in figure 1.
1.1.2. Gateway end system block diagram
The gateway end needs to implement more types of functions, and first needs to collect data information transmitted from the terminal LoRa module, analyze and process the collected data information, and finally present the analyzed information in a screen, as shown in fig. 2.
And observing a system block diagram, wherein the gateway end is adapted with an LED function plate, and different LED lamp flickers represent different working states and data information transmission and receiving states. The key board has the core function of regulating and controlling the transmission state of polling data. The core function of the LoRa module is to receive signals transmitted by the terminal, the signals are collected and then directly transmitted to the MCU to be analyzed, and the main function of the upper computer board is to present the analyzed data on a working panel of a PC (personal computer) end of a worker, so that a user can clearly see the data condition sent by the DMB terminal.
1.2. Debugging software
And (4) utilizing a parameter debugging tool matched with the LoRa module to allocate the parameter values of the module. The LoRa module on the terminal needs to do the work of directly transmitting the collected terminal state information to the gateway terminal without allocating the parameters, in other words, the LoRa module on the terminal is self-adaptive to specific parameter values, and a developer only needs to apply the software to allocate the parameters and then directly associate the parameters with the terminal.
1.3.LoRa Module
The wireless signal transmission module independently researched and developed by the atomic company at the right point is selected in the research work, the specific model is 01-LoRa-ATK, and the module has a plurality of excellent characteristics such as: low energy consumption, long-distance wireless signal transmission, low power, smaller specification and the like. The module is self-adapting to 6 pins through which it needs to be associated with an external scene. And the LoRa module of this model can also be directly through serial port come with STM32 singlechip relevant.
The LoRa module is a protocol and a product for communication in the whole system, data is sent to broadcast through serial port data simulation, then the broadcast can be fed back to an LED screen through the protocol, if the data is sent all the time, the feedback can be received all the time, when the information cannot be received normally, the broadcast can be judged to have problems, and then workers can be arranged to go forward to investigate.
2. Functional implementation of a system
2.1 LoRa System design
2.1.1.LoRa networking mode
The LoRa module communication function comprises transparent transmission and directional transmission. As shown in fig. 3, the system uses the directional transmission function of the LoRa module to enable the gateway to sequentially send polling request data to the node according to a certain sequence, and when the node receives the polling request data once, the data is returned to the gateway through the directional transmission function. It is expected that 1s to 2s completes polling one node and 30 to 60 nodes can complete data reception in one minute. The specific time needs to be determined after subsequent debugging.
2.1.2. Node frame
The node is in a receiving state when idle, once receiving data, the data is compared with appointed polling request data, if the signals are the same, the address and the channel of the gateway are added in front of a frame of complete data, and the data is returned to the gateway through directional transmission. If the data is not the same as the polling request signal, the receiving state is still maintained. Fig. 4 introduces a framework flow of the node part.
2.1.3. Gateway framework
The gateway needs to continuously send polling request data, after the polling request data is sent for one time, whether the data returned by the slave is received or not is judged, if yes, the data is sent to the computer through the serial port, and the address of the node is polled to be +1. If the slave machine return data is not received after time out, skipping the request and polling the next node. Figure 5 introduces a framework flow for the gateway end portion.
2.1.4. Integral design
The whole part contains the node terminals and the gateways as shown in figure 6. The gateway contains gateway polling module, loRa module, host computer, loRa configuration module, button module, LED lamp module, and wherein the loRa configuration module can dispose the loRa parameter when last electricity, and after the parameter setting, gateway polling module can control the loRa module and send the polling request signal to each node terminal, if receive the data that the node returned, alright with the host computer of uploading data through the serial ports. The node terminal comprises a DMB terminal, an LoRa radio frequency module and a LoRa configuration module, wherein when the LoRa module receives a polling request signal sent by the gateway terminal, the DMB terminal can be controlled to send data to the gateway.
2.2. Hardware design of each part of monitoring system
The hardware design of the whole system can be divided into the following two parts:
1. node terminal
2. Gateway
The terminal and the gateway end all adopt LoRa modules with the same specification, the built-in chip model of the module is SX1278, and the LoRa modules are all the type 01-LoRa-ATK modules developed by the same company. The specific association between the DMB system terminal and the gateway can be observed through fig. 7.
2.2.1 LoRa radio frequency module
The LoRa module model and specification that this time gateway end and terminal were used are identical, are the wireless signal transmission module of model 01-LoRa-ATK, and this module embeds the core chip model and is SX1278, and the inside other external circuit that still adapts on this chip's basis of module after the encapsulation. The module has many advantageous properties such as: the wireless signal transmission and collection module has the advantages of high signal transmission precision, long transmission distance, low energy consumption, small specification and the like, and is extremely high in applicability.
2.2.2. Terminal node hardware design
The hardware design of the terminal node is not many and is mainly based on the DMB terminal design that has been developed. And the LoRa radio frequency module is connected with the DMB terminal through a serial port. VCC, GND, RXD and TXD of the DMB terminal are respectively connected with VCC, GND, TXD and RXD of the LoRa module. It is important to note that TXD and RXD should be cross-connected.
2.2.3. Gateway side hardware design
The modules involved in the gateway end hardware design are as follows:
1. upper computer
LED Lamp Module
3. Key module
LoRa Module
The functional components on the gateway side have been fully explained above in the form of a system block diagram. The following explains how to associate the function modules on the gateway side.
1) Hardware design of LED lamp
The gateway end has set up two LED lamps, and the in-process LED lamp that will be according to actual conditions will be sent out at external transmission and collection information and allotment parameter as gateway end loRa module.
The LED0/1 needs to be matched with a resistor with the specification of 550 omega and then is associated with a power supply, the other end of the LED needs to be directly associated with a PE5 pin, and the fact that the two lamps can emit light when the level state is low and do not emit light when the level state is high can be found by observing the internal circuit structure. Therefore, the purpose of light emission can be achieved only by adjusting the level states of the two LED ports to be low.
2) Hardware design of key module
The gateway end is also adapted with key modules with different functions, specifically: KEY0/1 and WK _ UP. The development board purchased this time is pre-adapted with four keys, and one key can execute reset operation. And the system building work only needs to apply other three keys except for resetting.
Observing the KEY principle diagram, it can be found that one end of the KEY WK _ UP needs to be directly associated with the PA0 pin, the other end needs to be directly associated with the power supply, the KEY0 port needs to be directly associated with the pin PE4, the KEY1 KEY port needs to be directly associated with the pin PE3, and the other ends of the two KEYs need to be directly associated with the ground wire. When the user operates the WK _ UP button, the level state at the pin PA0 is high, and when the user operates the other two buttons, the level state at the PE4/3 port is low. Therefore, the user can directly achieve the purpose of himself by operating the keys.
3) Hardware design of LoRa module
The gateway end must configure a LoRa MODULE identical to the terminal to collect the running state information of the terminal, and the development board purchased this time is self-adapted with a USART3 serial port, and the port and the pin PA4/15 together extend a MODULE-ATK MODULE, so we only need to associate the LoRa MODULE purchased in advance with the MODULE.
It can be seen from observing the schematic diagram that the RXD pin of the module needs to be directly associated with the PB10 pin on the singlechip, and the TXB pin needs to be directly associated with the PB11 pin on the singlechip. The actual role of the PB10/11 is to accomplish the bi-directional transmission of data information. The KEY pin is associated with a PA4 pin on the singlechip, and the LED end needs to be directly associated with a PA15 pin on the singlechip. After the connection work between the module and the single chip microcomputer is completed, the LoRa module needs to be associated with the module, one end of a TXD pin and an RXD pin on the LoRa module needs to be staggered and associated with the TXD pin and the RXD pin on the module, the other end of the TXD pin and the RXD pin needs to be associated with a power supply, the AUX pin on the LoRa module needs to be directly associated with a KEY, and the MD0 pin needs to be directly associated with an LED. When the module is in the configuration working state, the user needs to implement the function of allocating the module parameters by means of transmitting AT instructions.
The LoRa module is arranged on the right side of the development board, the KEY modules are arranged on the three yellow KEYs on the lower right side of the development board, polling data transmission is started when the KEY _ UP KEY is pressed down, and polling data transmission is stopped when the red KEY is pressed down. And an LED indicator lamp is arranged beside the red key, when the red key flashes once, the LED indicator lamp sends polling data once, and when the red key flashes once, the LED indicator lamp receives data sent to the gateway by the node.
2.3. Software design
2.3.1. Terminal node software design
Because the reserved serial port of the DMB terminal has large data sending quantity and too fast speed, the LoRa transmission data can be seriously lost. Considering that the source code of the DMB terminal is already shaped, it cannot be directly modified. A code simulating the original data transmission is rewritten in the DMB terminal to perform the test.
Firstly, an array is defined, data in the array simulates data sent by a DMB terminal serial port, and a channel identifier is added behind original data, so that data sent by the node can be distinguished at a gateway terminal.
The code will turn on the yellow light, then send a string of data in the array, then let the red light flash once, after a delay of 1.9s, again perform the above function. The function that is finally realized is that the DMB terminal packetizes and transmits data once every 2 s. Although this is not data that the DMB terminal really transmits, it can be verified that the gateway terminal can correctly receive the data. And in the later stage, an external MCU is connected to the serial port of the DMB terminal, the MCU identifies a frame head and a frame tail of data transmitted by the serial port of the DMB terminal, a complete string of data is intercepted according to a frame head and frame tail identification, the string of data is temporarily stored, and the data is transmitted according to the requirement.
2.3.2. Gateway-side LoRa parameter configuration code
Since the LoRa module at the gateway needs to continuously transmit polling signals to each node terminal, and also needs to receive data transmitted from the DMB terminal and upload the data to the MCU, the parameter configuration of the LoRa module needs to be adjusted to implement different function selections.
In this project, this loRa's configuration code can effectively realize the parameter configuration to the loRa module, because in this project with loRa module lug connection on terminal node, also appeared can't dismantle the module alone when saving space, is difficult to carry out the problem of independent configuration. When considering scenic spot practical application, the same problem that can't dismantle loRa module one by one and carry out parameter adjustment exists, uses this code can realize loRa module's autonomic parameter configuration, solves above problem to the portability has been improved greatly.
2.3.3. Gateway side software design
For the whole system building work, the most core work is program compiling at the gateway end, because the LoRa module purchased at this time is adapted to the official function program example. Therefore, the compiling work of the gateway-side driving source code can be completed only by slightly modifying the example program according to the function realization requirements of the gateway-side driving source code. Several kernels will be selected for explanation.
1) Power-on detection design
After the power is switched on, in order to realize the functions on the gateway normally, the relevance of all modules must be detected, so that a module detection feedback function is specifically compiled for the operation.
LoRa _ check _ cmd () is a detection feedback function, and the entry position of the function shows a specific parameter which can refer to a specific feedback result, and the feedback value is specifically 0 or any value. If the value of the final feedback parameter is 0, the result indicates that the expected feedback result is not detected; but ultimately other values, then indicating the expected feedback result detected, the program specified by the result may be invoked and run. The mechanism of application of the function is: when the if statement collects data information, it will automatically call the strstrstr () function, which functions as: and the value obtained by the feedback of the second inlet represents the specific position of the parameter at the first inlet, so that whether the second inlet is a substring of the first inlet is evaluated, and the obtained feedback value is directly given to the str variable, so that the feedback value finally obtained by detecting the feedback function is equal to the specific value of the str variable.
The LoRa _ check _ cmd () function can externally transmit instructions, and the function has three entries in total, wherein each entry corresponds to one parameter: first, waitime parameter; second, ack parameter; and thirdly, cmd parameter. The specific meaning referred by the Waitime parameter is feedback time, and the minimum unit is 10 milliseconds; the ack parameter refers to the expected feedback value; the specific meaning of cmd is an instruction string. The feedback value res detected by the function is only 0 or 1, when the feedback value is 1, the instruction transmission is wrong, the feedback value is 0, the instruction transmission is finished, and the res value is 0 in the initial state. Before transmitting the instruction, the system pre-evaluates whether the cmd address does not exceed 0xff, and if the cmd address does not exceed 0xff, the system transmits data information outwards; the command string information is transmitted to the outside on the assumption that the exceedance is exceeded. After information transmission is completed, whether feedback needs to be waited or not needs to be evaluated, if the feedback needs to be waited, while the function of while is called to enter a function loop, the function of LoRa _ check _ cmd () is automatically called in the loop process to evaluate whether the feedback result is an expected response result, if the evaluation result is yes, the loop function is automatically closed, res is assigned with 0, but if the expected feedback result is not detected in the loop, the loop is also closed, and res is assigned with 1. This partial program evaluation feedback process can be observed by fig. 8.
2) Module initialization function
LoRa _ Init () is a function for executing a reset operation, which does not have an entry parameter, and the interval of the feedback value temp is 0 or 1, and when the feedback value is 0, it means that the detection is completed, and when the feedback value is 1, it means that an error occurs in the detection.
When the function is applied, the GPIO and the interrupt source need to be deployed, and after the deployment is completed, the operating condition of the current module needs to be evaluated, that is, whether the level state on the AUX terminal is low is scanned, and if the module is currently in a busy state, the function enters infinite loop. However, if the feedback-derived module is currently in an idle state, a reset operation is performed on the serial port 3, and the MD0 level state on the LoRa module is synchronously adjusted to be high, at this time, the module enters a deployment mode, and then the function needs to perform three detections on the module. In the detection process, a cmd function needs to be called to transmit an AT command to a module, the module in the mode receives the AT command and then feeds back a receiving result to a function inlet, a value 0 is fed back when the module succeeds all the three detection operations, but a value 1 is finally fed back if the module does not succeed all the time, which means that the detection is wrong. This partial program evaluation feedback process can be observed by fig. 9.
3) Design of polling function
In the project, a networking mode is designed by utilizing the directional transmission function of LoRa. The gateway sends polling request data to the nodes in sequence according to a certain sequence, and the nodes return the primary data to the gateway through the directional transmission function after receiving the primary polling request data.
2.3.4. Program execution flow
The execution flow of the whole program is shown in fig. 10, firstly parameter configuration is performed on the LoRa module through codes, and then polling can be formally started after configuration and preparation work is completed, the polling request data is sent by the gateway, the node terminal returns the data to the gateway after receiving the polling request data, the gateway transmits the data to an upper computer (namely, a PC end) through a serial port after receiving the data sent by the node end, and the data can be clearly checked through a serial port debugging assistant.
2.3.5.PCB edition optimization design
The PCB of the system is optimized during design, and the original PCB layout has the following problems:
first, lacking a remote monitoring system, the staff cannot know the first time when the device cannot work.
Secondly, the antenna wiring adopts the right angle, produces parasitic capacitance and parasitic inductance easily, and the LED lamp is diode drive, comparatively nonstandard.
The current PCB layout is mainly optimized as follows:
firstly, add the loRa module on the basis of original receiver PCB territory, realized the remote monitoring function of system for the staff can in time discover the problem.
Secondly, the wiring is optimized, and because the capability of the pin of the single chip microcomputer for outputting current is limited, the triode is used as a switch to drive the LED lamp. Therefore, the LED lamp is changed into triode driving in optimization. Meanwhile, the routing of the antenna is changed from the original right-angle routing into arc routing, so that the generation of additional parasitic capacitance and parasitic inductance is avoided.
Example 3
3.1 connectivity test
The equipment to which the test work needs to be applied is specifically: one charger is used for supplying power; one gateway end is arranged; thirdly, DMB system terminal equipment is arranged; fourth, notebook computer one, gateway end and a terminal loRa module need directly be associated with the computer, drive through the 5V power, and two other loRa modules then need to be associated with the treasured that charges, drive through 5V voltage.
3.2 data reception testing
After the connectivity test is finished, a formal testing link can be started. After pressing the KEY _ UP KEY, the gateway end sends polling data, at the moment, the red light of the gateway end flickers, and each time the red light flickers, the data is sent; and when the green light of the gateway end flickers, the gateway end receives the data sent from the node terminal.
The gateway end can transmit the data information to the computer again through the serial port after collecting the transmitted data information, and then a developer can watch the transmitted data information only through a serial port debugging tool.
3.3 distance test
In the distance test, since the field test cannot be performed in the scenic spot, the test is selected to be performed inside the school. In order to simulate the situation in the scenic spot as much as possible, two node terminals are respectively placed at different positions, and the old playground of Chongqing post and telecommunications university is selected as a test position. The scene diagram is shown in fig. 11.
The weather condition of the test work on the same day is good, the regional cataract is few, and the antenna height is not high. The specific results of data information transmission at different distances are shown in table 1. The LoRa-related parameter settings in the system are shown in table 2.
TABLE 1 4dBi gain antenna test results
| Distance (m) | Effect |
| <＝500m | Data can be stably received |
| 500m-600m | The antenna position is adjusted and fixed, and then the data can be stably received |
| >600m | No data can be received |
Table 2 LoRa parameter in test
| Parameter(s) | Numerical value |
| Rate in air | 19.2K |
| Transmitting power | 20dBm |
| Antenna gain | 4dBi |
Before carrying out test work, firstly, the signal transmission rate of the LoRa module needs to be allocated, specifically: the signal transmission rate is: 19.2K, the signal generation power value is 20dBm, the signal transmission frequency value interval is 413-453MHz, the parameter specification of the antenna is 4dBi, and the antenna is directly related to the LoRa module through an SMA pin.
The LoRa module and the receiving device of the terminal need to be powered through the charger, all devices at the gateway end need to be powered through the notebook computer, and the notebook computer is carried to move far after the terminal is correctly placed. During the test it can be found:
1. the transmission of the signal will be slightly distorted during the movement, but normal transmission accuracy will be restored once the movement is stopped;
2. the smoothness of the signal transmission is higher if the antennas on the terminal and gateway sides can be placed higher.
3. Within 500m, signals can be stably received; when the distance is between 500m and 600m, the signal receiving is unstable, and the signal can be received only by adjusting the direction of the antenna and lifting equipment; when the distance is larger than 600m, the gateway end cannot receive signals. 600m is the limit distance for antennas equipped with the current model.
The test environment of this time choosing still has the student to make a round trip to move, and because the reason antenna of circuit can not place in the eminence moreover, so can deduce, if the system antenna place in more eminence and the scene is spacious then system signal transmission's distance can also be bigger. It is also found in the test work that the quality and smoothness of signal transmission are greatly related to the height and number of obstacles, so the antenna should be placed higher in practical application, for example: the roof, etc., so that the signal transmission quality can be effectively improved.
Finally, the above embodiments are only intended to illustrate the technical solutions of the present invention and not to limit the present invention, and although the present invention has been described in detail with reference to the preferred embodiments, it will be understood by those skilled in the art that modifications or equivalent substitutions may be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions, and all of them should be covered by the claims of the present invention.
Claims (4)
1.DMB terminal state information receiving system based on loRa technique, its characterized in that: the system comprises a node terminal and a gateway;
the node terminal and the gateway are provided with a digital multimedia broadcasting technology DMB terminal and a long-distance radio LoRa module which are connected in sequence;
the LoRa module is also in data connection with the MCU;
the MCU is also connected with the LED module, the upper computer and the key module respectively;
the DMB terminal transmits data into the LoRa module through the associated port, the LoRa module integrates data information into a digital signal, and partial data information is transmitted to the MCU in a wireless transmission mode;
the MCU collects the data information transmitted by the LoRa module, analyzes and processes the collected data information, and finally displays the analyzed information in a screen;
the LED module is used for representing different working states and data information transmission and receiving states;
the key module regulates and controls the transmission state of polling data;
the upper computer displays the analyzed data on a PC (personal computer) end of a worker;
the communication of the LoRa module comprises transparent transmission and directional transmission;
the directional transmission is as follows: the method comprises the steps that a gateway sends polling request data to nodes in sequence according to a certain sequence, and when the nodes receive the polling request data every time, the data are returned to the gateway through directional transmission; the polling of one node is expected to be completed within 1 s-2 s, and the data receiving of 30-60 nodes is completed within one minute;
in the information receiving system, the node is in a receiving state when idle, and when receiving data, the data is compared with agreed polling request data; if the signals are the same, adding the address and the channel of the gateway before a frame of complete data, and returning the address and the channel to the gateway through directional transmission; if the data is different from the polling request signal, the terminal is in a receiving state;
the gateway continuously sends polling request data, after the polling request data is sent for one time, whether the data returned by the slave is received or not is judged, if yes, the data is sent to a computer through a serial port, and the address of a polling node is +1, and polling of the next node is carried out; if the slave machine return data is not received after overtime, skipping the request and polling the next node;
the gateway comprises a gateway polling module, an LoRa module, an upper computer, a LoRa configuration module, a key module and an LED lamp module, wherein the LoRa configuration module configures LoRa parameters when being electrified, after the parameters are set, the gateway polling module controls the LoRa module to send polling request signals to each node terminal, and if data returned by the nodes are received, the data are uploaded to the upper computer through a serial port; the node terminal comprises a DMB terminal, an LoRa radio frequency module and an LoRa configuration module, wherein when the LoRa module receives a polling request signal sent by the gateway terminal, the DMB terminal is controlled to send data to the gateway.
2. The DMB terminal status information receiving system based on the LoRa technique as recited in claim 1, wherein: the built-in chip model of the LoRa module is SX1278;
the LoRa radio frequency module is a wireless signal transmission module of 01-LoRa-ATK, and the model of the built-in core chip is SX1278;
connecting the LoRa radio frequency module with the DMB terminal through a serial port; a power supply voltage VCC of the DMB terminal, a grounding point GND, a pin RXD for receiving data and a pin TXD for sending data are respectively connected with VCC, GND, TXD and RXD of the LoRa module; wherein TXD is cross-connected with RXD.
3. The DMB terminal status information receiving system based on the LoRa technique as recited in claim 1, wherein: the RXD is associated with a PB10 pin on the singlechip, and the TXB pin is directly associated with a PB11 on the singlechip; the PB10/11 is used for completing the bidirectional transmission of data information; the KEY pin is related to a PA4 pin on the single chip microcomputer, and the LED end is directly related to a PA15 pin on the single chip microcomputer.
4. The DMB terminal status information receiving system based on the LoRa technique as recited in claim 1, wherein: in the information receiving system, an array is defined, data in the array simulates data sent by a DMB terminal serial port, a channel identifier is added behind original data, and data sent by a node is distinguished in a gateway terminal.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108494815A (en) * | 2018-02-06 | 2018-09-04 | 北京极智感科技有限公司 | A kind of method and system of transmission message |
| WO2020134554A1 (en) * | 2018-12-26 | 2020-07-02 | 中兴通讯股份有限公司 | Data transmission method and device, and computer readable storage medium |
| EP3692683A1 (en) * | 2017-10-02 | 2020-08-12 | Woodenshark LLC | Systems including a gateway receiving sensor data, and related methods |
| US10958463B1 (en) * | 2018-03-26 | 2021-03-23 | Lynq Technologies, Inc. | Pairing multiple devices into a designated group for a communication session |
| CN112953934A (en) * | 2021-02-08 | 2021-06-11 | 重庆邮电大学 | DAB low-delay real-time voice broadcasting method and system |
| CN114222269A (en) * | 2021-11-30 | 2022-03-22 | 深圳市领创星通科技有限公司 | Method for enhancing reliability of multi-node transmission |
| CN114221894A (en) * | 2021-12-27 | 2022-03-22 | 中科海微(北京)科技有限公司 | Internet of things networking loss prevention system and method |
-
2022
- 2022-06-01 CN CN202210621336.4A patent/CN115276864B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP3692683A1 (en) * | 2017-10-02 | 2020-08-12 | Woodenshark LLC | Systems including a gateway receiving sensor data, and related methods |
| CN108494815A (en) * | 2018-02-06 | 2018-09-04 | 北京极智感科技有限公司 | A kind of method and system of transmission message |
| US10958463B1 (en) * | 2018-03-26 | 2021-03-23 | Lynq Technologies, Inc. | Pairing multiple devices into a designated group for a communication session |
| WO2020134554A1 (en) * | 2018-12-26 | 2020-07-02 | 中兴通讯股份有限公司 | Data transmission method and device, and computer readable storage medium |
| CN112953934A (en) * | 2021-02-08 | 2021-06-11 | 重庆邮电大学 | DAB low-delay real-time voice broadcasting method and system |
| CN114222269A (en) * | 2021-11-30 | 2022-03-22 | 深圳市领创星通科技有限公司 | Method for enhancing reliability of multi-node transmission |
| CN114221894A (en) * | 2021-12-27 | 2022-03-22 | 中科海微(北京)科技有限公司 | Internet of things networking loss prevention system and method |
Non-Patent Citations (2)
| Title |
|---|
| CHANGQING SUN ET AL.: "Design and Implementation of Cloud-based Single-channel LoRa IIoT Gateway Using Raspberry Pi", 《CHINESE CONTROL CONFERENCE (CCC)》, 9 September 2020 (2020-09-09), pages 5259 - 5263 * |
| 张红升 等: "DMB单频网及适配器电路的设计与实现", 《重庆理工大学学报(自然科学)》, vol. 35, no. 6, 30 June 2021 (2021-06-30), pages 185 - 194 * |
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