A LoRaWAN Intelligent Radio Frequency Channel Selection Method

Abstract

The present invention discloses a LoRaWAN intelligent radio frequency channel selection method, which includes: the gateway performs multiple frequency sweeps on a preset frequency band periodically at a first period, reads the multiple received signal strengths of each channel within the preset frequency band, performs mean processing, and then sends them to the network server for recording and storage; the network server sets every 8 channels as a group according to the frequency order to group the channels; the network server gives the average received signal strength of each channel group based on the average received signal strength of each channel collected within a second period in combination with the channel grouping; takes the channel group with the optimal average value as the target channel group, and issues the target channel group information and the channel switching time point to the terminal during the channel configuration time period; when the channel switching time point is reached, the network server issues the target channel group information to the gateway, and the gateway and the terminal reset their working channels according to the target channel group information at the channel switching time.

Description

Technical Field

[0001] The present invention relates to the technical field of LoRa, and in particular to a LoRaWAN intelligent radio frequency channel selection method. Background Art

[0002] LoRa is a new type of wireless network spread spectrum modulation communication technology. LoRa has the advantages of long transmission distance, low power consumption, low cost, and large-scale networking. With the development of the Internet of Things industry, LoRaWAN has attracted more and more attention in the industry.

[0003] LoRaWAN is a set of communication protocols and system architectures based on LoRa radio frequency communication for realizing the design of a long-distance communication network. The LoRaWAN communication system usually includes three parts: a terminal (or called a node), a gateway, and a network server (NS).

[0004] The terminals in the LoRaWAN communication system are divided into three categories: Class-A, Class-B, and Class-C.

[0005] Class-A terminals report data on demand using the ALOHA protocol. Two short downlink reception windows will follow each uplink to achieve two-way transmission. This operation is the most power-saving. Class-A terminals must wait for the terminal to report data before sending data to it. Its application scenarios are usually trash can monitoring, smoke alarms, gas monitoring, etc.

[0006] Class-B terminals, in addition to having the random reception windows of Class-A terminals, will also open a reception window at a specified time, which is called the terminal fixed reception window. In order for Class-B terminals to open the reception window at the specified time, Class-B terminals need to receive time synchronization beacons from the gateway. The network server can send data to Class-B terminals in the terminal fixed reception window. Its application scenarios are usually valve-controlled water and gas meters, etc.

[0007] Class-C terminals basically keep the reception window open all the time and only briefly close it when sending. Since Class-C terminals are in a continuous reception state, data can be sent to the terminal at any time. Its application scenarios are usually street lamp control, etc. Class-C terminals consume more power than Class-A terminals and Class-B terminals.

[0008] The network access methods of LoRaWAN include OTAA and ABP. The full name of OTAA is Over-The-Air Activation, which is the over-the-air activation method. The network access steps of OTAA are as follows: The JoinRequest message sent by the terminal is forwarded to the network server NS through the gateway; after the network server NS makes some judgment and processing on this request, it sends the JoinAccept message to the terminal through the gateway.

[0009] Existing LoRaWAN gateways need to manually set the frequency bands of the receiving channels, so it is impossible to select the channel frequency bands with better network performance. And over time, the deployed Lora environment may also change. If the frequency bands of the receiving channels of the LoRaWAN gateway are not adjusted, it will affect the LoRaWAN network performance, resulting in data packet conflicts and packet losses. Summary of the Invention

[0010] In view of the above deficiencies of the prior art, the purpose of the present invention is to provide a LoRaWAN intelligent radio frequency channel selection method, which can intelligently select the channel frequency bands with better LoRaWAN network performance and reduce data packet conflicts and packet losses.

[0011] To achieve the above purpose, the present invention provides a LoRaWAN intelligent radio frequency channel selection method, including:

[0012] The gateway periodically sweeps the preset frequency band at the first period, reads the received signal strengths of each channel within the preset frequency band; records the multiple sweep results of each channel, performs mean processing on the received signal strengths of each channel, and then sends the average value of the received signal strengths of each channel to the network server for recording and storage;

[0013] The network server sets every 8 channels as a group in the order of frequency to group the channels;

[0014] The network server calculates the mean value of the multiple received signal strength average values of each channel collected within the second period at the second period, gives the average value of the received signal strength of each channel within the second period, and then performs mean value calculation according to the channel grouping to give the average value of the received signal strength of each channel group; takes the channel group with the optimal average value of the received signal strength as the target channel group, and sends the target channel group information and the channel switching time point to the terminal during the channel configuration time period;

[0015] When the network server reaches the channel switching time point, it sends the target channel group information to the gateway, and the gateway resets the working channel of the gateway according to the target channel group information;

[0016] After the terminal reaches the channel switching time point, it resets the working channel of the terminal according to the target channel group information.

[0017] Further, for Class-A terminals, the method of sending the target channel grouping information to the terminals is as follows:

[0018] During the channel configuration period, Class-A terminals randomly report a request message for obtaining the latest channels within this period.

[0019] When the network server receives the request message for obtaining the latest channels uploaded by Class-A terminals, it sends the target channel grouping information and the channel switching time point.

[0020] After reaching the channel switching time point, Class-A terminals reset the working channels of the terminals according to the target channel grouping information.

[0021] Further, for Class-B terminals, the method of sending the target channel grouping information to the terminals is as follows:

[0022] Set the channel configuration time within the fixed receiving window of Class-B terminals.

[0023] During the channel configuration period, the network server sends a request message for configuring channel information to the terminals through the gateway, and sends the target channel grouping information to the terminals.

[0024] After receiving the target channel grouping information, Class-B terminals send a response channel configuration message to the network server.

[0025] After reaching the channel switching time point, Class-B terminals reset the working channels of the terminals according to the target channel grouping information.

[0026] Further, for Class-C terminals, the method of sending the target channel grouping information to the terminals is as follows:

[0027] During the channel configuration period, the network server sends a request message for configuring channel information to the terminals through the gateway, and sends the target channel grouping information to the terminals.

[0028] After receiving the target channel grouping information, Class-C terminals send a response channel configuration message to the network server.

[0029] After reaching the channel switching time point, Class-C terminals reset the working channels of the terminals according to the target channel grouping information.

[0030] Further, if the terminals do not obtain the target channel grouping information within the channel configuration period, a re-networking procedure is initiated.

[0031] Further, the method of sending the target channel grouping information to the gateway is as follows:

[0032] After the network server reaches the channel switching time point, it sends a configuration channel information request message to the gateway, and issues the target channel group information to the gateway. After receiving the target channel group information, the gateway updates the channel configuration, then restarts the program, and after the restart program is successful, it sends a successful update reply to the network server.

[0033] Furthermore, the length of the second period is one day or N days, where N is a positive integer.

[0034] The present invention achieves the following technical effects:

[0035] By adopting the LoRaWAN intelligent radio frequency channel selection method of the present invention, the LoRaWAN network can intelligently select a channel frequency band with better LoRaWAN network performance, reducing data packet conflicts and packet losses. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 is the information flow chart among the terminal, gateway and network server of LoRa of the present invention;

[0037] Figure 2 is the flow chart of obtaining the optimal channel group of the received signal strength of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0038] To further illustrate the embodiments, the present invention provides drawings. These drawings are part of the disclosure of the present invention, mainly used to illustrate the embodiments, and can be used to explain the operation principle of the embodiments in conjunction with the relevant descriptions in the specification. With reference to these contents, those of ordinary skill in the art should be able to understand other possible implementation manners and the advantages of the present invention.

[0039] The present invention will be further described below in conjunction with the drawings and specific embodiments.

[0040] Embodiment 1

[0041] As Figure 1 and Figure 2 shown, the present invention provides a LoRaWAN intelligent radio frequency channel selection method.

[0042] In LoRaWAN, it can be considered to include three layers of devices: a terminal, a gateway, and a network server NS.

[0043] Among them, the terminal: accesses the network through OTAA (such as Figure 1 the OTAA join request, OTAA join accept and other instructions in ), and after successful network access, obtains the device time through the LoRaWAN V1.0.3 standard protocol (such as the DeviceTimReq, DeviceTimAns and other messages in the figure).

[0044] Gateway side: Through the internal LoRa RF chip sx126x, it performs periodic frequency scanning on the preset frequency band (for example, in China, the available uplink frequency band is 470.3 - 489.3 MHZ, with a total of 96 channels, a channel bandwidth of 125 KHz, and a step size of 200 KHz) at the first period (such as one hour), obtains multiple groups of received signal strength RSSI of each channel, and performs average processing respectively to obtain the average received signal strength of each channel. After scanning each period, it uploads the average received signal strength of each channel to the network server.

[0045] Network server NS: The network server NS records the average received signal strength of each channel. The network server NS calculates the average value of the RSSI data collected multiple times (such as the data volume of one day) at the second period (such as one day or N days, where N is a positive integer) to obtain the average received signal strength of each channel within the second period. Divide the 96 channels into 16 channel groups with every 8 channels as a group, and perform average processing on the average received signal strength of each channel in each channel group again to calculate the average received signal strength of each channel group. Compare the average received signal strength of the 16 channel groups, and select the channel group with the best received signal strength as the target channel group; the network server NS will reset the working channel according to the target channel group information.

[0046] In the application, the uplink channel and downlink channel of LoRa are bundled and configured. When the uplink channel is set through the target channel group information, the downlink channel is also set at the same time.

[0047] In this embodiment: From 00:00 to 00:30 every day is the set channel setting time period, and 02:00 every day is the set channel switching time point.

[0048] 1) For Class-B terminals and Class-C terminals, the network server NS sends the target channel group information at 00:00 every day. Specifically, it includes the following steps: The network server sends a configuration channel information request message to Class-B terminals and Class-C terminals through the gateway during the channel configuration time period, and sends the target channel group information to Class-B terminals and Class-C terminals; after receiving the target channel group information, Class-B terminals and Class-C terminals send a response channel configuration message to the network server. Among them, for Class-B terminals, the channel configuration time needs to be set in the terminal fixed receiving window of the Class-B terminal first.

[0049] 2) For Class-A terminals, after 00:00 every day, a request message for obtaining the latest channel is randomly reported within 30 minutes. The network server NS issues a configured channel information message containing target channel group information and channel switching time point information. If the terminal does not receive the configured channel information message issued by the network server NS, the terminal continuously sends the request message for obtaining the latest channel until it receives the configured channel information message issued by the network server NS.

[0050] 3) After reaching the channel switching time point, the network server NS issues the target channel group information to the gateway, and the gateway resets its working channel according to the target channel group information. Specifically, after reaching the channel switching time point, the network server sends a configured channel information request message to the gateway to issue the target channel group information to the gateway. After receiving the target channel group information, the gateway updates its channel configuration and then restarts the program. After the restart of the program is successful, the gateway sends a success reply for the update to the network server.

[0051] 4) After reaching the channel switching time point, the terminal resets its working channel according to the target channel group information. For a terminal that has not received the target channel group information, a re-networking mechanism is started.

[0052] By adopting the LoRaWAN intelligent radio frequency channel selection method of the present invention, the LoRaWAN network can intelligently select a channel frequency band with better LoRaWAN network performance, reducing data packet conflicts and packet losses.

[0053] Although the present invention has been specifically shown and described in combination with the preferred embodiments, those skilled in the art should understand that various changes can be made to the present invention in terms of form and details without departing from the spirit and scope of the present invention defined by the appended claims, and all of them fall within the protection scope of the present invention.

Claims

1. A LoRaWAN intelligent radio frequency channel selection method, characterized in that Including: The gateway performs frequency scanning on a preset frequency band periodically at a first period, and reads the received signal strength of each channel within the preset frequency band; Record the frequency scanning results of each channel, perform mean processing on the received signal strength of each channel, and then send the average value of the received signal strength of each channel to the network server for recording and storage; The network server sets every 8 channels as a group in the order of frequency, and groups the channels; The network server calculates the mean value of the average received signal strength of each channel collected during the second period and periodically scanned and sent by the gateway during the first period at a second period, gives the average received signal strength of each channel during the second period, and then calculates the mean value according to the channel grouping, and gives the average received signal strength of each channel group; The channel group with the optimal average received signal strength is used as the target channel group, and the target channel group information and the channel switching time point are sent to the terminal during the channel configuration time period; When the network server reaches the channel switching time point, it sends the target channel group information to the gateway, and the gateway resets the working channel of the gateway according to the target channel group information; After the terminal reaches the channel switching time point, it resets the working channel of the terminal according to the target channel group information.

2. The LoRaWAN intelligent radio frequency channel selection method according to claim 1, wherein For Class-A terminals, the method of sending the target channel group information to the terminal is: During the channel configuration time period, Class-A terminals randomly report a request message for obtaining the latest channel during this time period; When the network server receives the request message for obtaining the latest channel uploaded by the Class-A terminal, it sends the target channel group information and the channel switching time point; After the Class-A terminal reaches the channel switching time point, it resets the working channel of the terminal according to the target channel group information.

3. The LoRaWAN intelligent radio frequency channel selection method according to claim 1, wherein For Class-B terminals, the method of sending the target channel group information to the terminal is: Set the channel configuration time in the fixed receiving window of the Class-B terminal; The network server sends a request message for configuring channel information to the terminal through the gateway during the channel configuration time period, and sends the target channel group information to the terminal; After the Class-B terminal receives the target channel group information, it sends a response channel configuration message to the network server; After the Class-B terminal reaches the channel switching time point, it resets the working channel of the terminal according to the target channel group information.

4. The LoRaWAN intelligent radio frequency channel selection method according to claim 1, characterized in that For Class-C terminals, the method of sending the target channel group information to the terminal is: The network server sends a request message for configuring channel information to the terminal through the gateway during the channel configuration time period, and sends the target channel group information to the terminal; After the Class-C terminal receives the target channel group information, it sends a response channel configuration message to the network server; After the Class-C terminal reaches the channel switching time point, it resets the working channel of the terminal according to the target channel group information.

5. The LoRaWAN intelligent radio frequency channel selection method according to claim 1, characterized in that When the terminal does not obtain the target channel group information within the channel configuration time period, start the re-networking procedure.

6. The LoRaWAN intelligent radio frequency channel selection method according to claim 1, wherein The method of sending the target channel group information to the gateway is: After the network server reaches the channel switching time point, it sends a configuration channel information request message to the gateway, and issues the target channel group information to the gateway. After receiving the target channel group information, the gateway updates the channel configuration, then restarts the program, and after the restart program is successful, it sends a success reply for the update to the network server.

7. The LoRaWAN intelligent radio frequency channel selection method according to claim 1, wherein The length of the second period is one day or N days, where N is a positive integer.

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